For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
1
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Functional Diagram
Features
• RF Bandwidth:
45 - 1050, 1400 - 2100, 2800 - 4200, 5600
- 8400 MHz
• Maximum Phase Detector Rate
100 MHz
• Ultra Low Phase Noise
-110 dBc/Hz in Band Typ.
• Figure of Merit (FOM) -227 dBc/Hz
• <180 fs RMS Jitter
• 24-bit Step Size, Resolution 3 Hz typ
• Exact Frequency Mode
• Built in Digital Self Test
• 40 Lead 6x6 mm SMT Package: 36 mm2
Typical Applications
• Cellular/4G, WiMax Infrastructure
• Repeaters and Femtocells
• Communications Test Equipment
• CATV Equipment
• Phased Array Applications
• DDS Replacement
• Very High Data Rate Radios
• Tunable Reference Source for Spurious-
Free Performance
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
2
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
General Description
The HMC834LP6GE is a low noise, wide band, Fractional-N Phase-Locked-Loop (PLL) that features an integrated Voltage
Controlled Oscillator (VCO) with a fundamental frequency of 2800 MHz - 4200 MHz, and an integrated VCO Output
Divider (divide by 1/2/4/6.../60/62) and doubler, that together allow the HMC834LP6GE to generate frequencies from
45 MHz to 1050 MHz, from 1400 MHz to 2100 MHz, from 2800 MHz to 4200 MHz, and from 5600 MHz to 8400 MHz.
The integrated Phase Detector (PD) and delta-sigma modulator, capable of operating at up to 100 MHz, permit wider
loop-bandwidths with excellent spectral performance.
The HMC834LP6GE features industry leading phase noise and spurious performance, across all frequencies, that
enable it to minimize blocker effects, and improve receiver sensitivity and transmitter spectral purity. The superior
noise oor (< -170 dBc/Hz) makes the HMC834LP6GE an ideal source for a variety of applications - such as; LO for
RF mixers, a clock source for high-frequency data-converters, or a tunable reference source for ultra-low spurious
applications.
Additional features of the HMC834LP6GE include RF output power control from 0 to 6 dB (~2 dB steps), output Mute
function, and a delta-sigma modulator Exact Frequency Mode which enables users to generate output frequencies
with 0 Hz frequency error.
Parameter Condition Min. Typ. Max. Units
RF Output Characteristics
Output Frequency
Band 1 45 1050 MHz
Band 2 1400 2100 MHz
Band 3 2800 4200 MHz
Band 4 5600 8400 MHz
VCO Frequency at PLL Input 2800 4200 MHz
RF Output Frequency at fVCO 2800 4200 MHz
Output Power
RF Output Power at fVCO = 4000 MHz
Across All Frequencies see Figure 9
Single-ended Power
Broadband Matched Internally
[1]
-2 0.5 2dBm
Output Power Control ~2 dB Steps 67.5 dB
RF Output Power at fVCO = 6000 MHz
Across All Frequencies see Figure 9
Single-ended Power
Broadband Matched Internally
[1]
-11 -9 -7 dBm
RF Output Power at fVCO = 8000 MHz
Across All Frequencies see Figure 9
Single-ended Power
Broadband Matched Internally
[1]
-13.5 -11 -8.5 dBm
Harmonics for Fundamental Mode
fo Mode at 4000 MHz 2nd / 3rd / 4th -25/-29/-38 dBc
fo/2 Mode at 4000 MHz/2 = 2 GHz 2nd / 3rd / 4th -25/-24/-35 dBc
fo/30 Mode at 2800 MHz/28 = 100 MHz 2nd / 3rd / 4th -20/-10/-26 dBc
fo/62 Mode at 2800 MHz/62 = 45 MHz 2nd / 3rd / 4th -14/-8/-21 dBc
Electrical Specications
VPPCP, VDDLS, VCC1, VCC2 = 5 V; RVDD, AVDD, DVDD3V, VCCPD, VCCHF, VCCPS = 3.3 V
Min and Max Specied across Temp -40 °C to +85 °C
[1] Measured single-ended. Additional 3 dB possible with differential outputs.
[2] Measured with 100  external termination. See Hittite PLL w/ Integraged VCOs Operating Guide Reference Input Stage section for more details.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
3
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Parameter Condition Min. Typ. Max. Units
Harmonics in Doubler Mode
2fo Mode at 5600 MHz 1/2 / 3rd / 4th/5th -10/-22/-25/-35 dBc
VCO Output Divider
VCO RF Divider Range 1,2,4,6,8,...,62 162
PLL RF Divider Characteristics
19-Bit N-Divider Range (Integer) Max = 219 - 1 16 524,287
19-Bit N-Divider Range (Fractional) Fractional nominal divide ratio
varies (-3 / +4) dynamically max 20 524,283
REF Input Characteristics
Max Ref Input Frequency 350 MHz
Ref Input Voltage AC Coupled
[2] 1 2 3.3 Vp-p
Ref Input Capacitance 5pF
14-Bit R-Divider Range 116,383
Phase Detector (PD) [3]
PD Frequency Fractional Mode B [4] DC 100 MHz
PD Frequency Fractional Mode A (and Register
6 [17:16] = 11) DC 80 MHz
PD Frequency Integer Mode DC 125 MHz
Charge Pump
Output Current 0.02 2.54 mA
Charge Pump Gain Step Size 20 µA
PD/Charge Pump SSB Phase Noise 50 MHz Ref, Input Referred
1 kHz -143 dBc/Hz
10 kHz Add 1 dB for Fractional -150 dBc/Hz
100 kHz Add 3 dB for Fractional -153 dBc/Hz
Logic Inputs
Vsw 40 50 60 % DVDD
Logic Outputs
VOH Output High Voltage DVDD V
VOL Output Low Voltage 0 V
Output Impedance 100 200
Maximum Load Current 1.5 mA
Power Supply Voltages
3.3 V Supplies AVDD, VCCHF, VCCPS,
VCCPD, RVDD,DVDD 3.0 3.3 3.5 V
5 V Supplies VPPCP, VDDLS, VCC1, VCC2 4.8 55.2 V
Power Supply Currents
+5 V Analog Charge Pump VPPCP, VDDLS 8mA
Electrical Specications (Continued)
[3] Slew rate of greater or equal to 0.5 ns/V is recommended, see PLL with Integrated RF VCOs Operating Guide for more details. Frequency is
guaranteed across process voltage and temperature from -40 °C to +85 °C.
[4] This maximum phase detector frequency can only be achieved if the minimum N value is respected. eg. In the case of fractional feedback
mode, the maximum PFD rate = fvco/20 or 100 MHz, whichever is less.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
4
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Electrical Specications (Continued)
Parameter Condition Min. Typ. Max. Units
+5 V VCO Core and VCO Buffer fo/1 Mode VCC2 105 mA
fo/N Mode VCC2 80 mA
+5 V VCO Divider and RF/PLL Buffer
Single-Ended Output Mode
fo/1 Mode VCC1 25 mA
Differential Output Mode
fo/1 Mode VCC1 40 mA
Single-Ended Output Mode
fo/N Mode VCC1 80 100 mA
Differential Output Mode
fo/N Mode VCC1 95 115 mA
+3.3 V AVDD, VCCHF, VCCPS,
VCCPD, RVDD, DVDD3V 52 mA
Power Down - Crystal Off Reg 01h=0,
Crystal Not Clocked 10 µA
Power Down - Crystal On, 100 MHz Reg01h =0,
Crystal Clocked 100 MHz 5mA
Power on Reset
Typical Reset Voltage on DVDD 700 mV
Min DVDD Voltage for No Reset 1.5 V
Power on Reset Delay 250 µs
VCO Open Loop Phase Noise at fo @ 4 GHz
10 kHz Offset -78 dBc/Hz
100 kHz Offset -108 dBc/Hz
1 MHz Offset -134.5 dBc/Hz
10 MHz Offset -156 dBc/Hz
100 MHz Offset -171 dBc/Hz
VCO Open Loop Phase Noise at fo @ 4 GHz/2 = 2 GHz
10 kHz Offset -83 dBc/Hz
100 kHz Offset -113 dBc/Hz
1 MHz Offset -139.5 dBc/Hz
10 MHz Offset -165.5 dBc/Hz
100 MHz Offset -167 dBc/Hz
VCO Open Loop Phase Noise at fo @ 2.8 GHz/28 = 100 MHz
10 kHz Offset -111 dBc/Hz
100 kHz Offset -141 dBc/Hz
1 MHz Offset -163.5 dBc/Hz
10 MHz Offset -170 dBc/Hz
100 MHz Offset -173 dBc/Hz
VCO Open Loop Phase Noise at 2fo @ 5.6 GHz
10 kHz Offset -77 dBc/Hz
100 kHz Offset -107 dBc/Hz
1 MHz Offset -132 dBc/Hz
10 MHz Offset -154 dBc/Hz
100 MHz Offset -162 dBc/Hz
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
5
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Parameter Condition Min. Typ. Max. Units
VCO Open Loop Phase Noise at 2fo @ 8 GHz
10 kHz Offset -70 dBc/Hz
100 kHz Offset -100 dBc/Hz
1 MHz Offset -127 dBc/Hz
10 MHz Offset -149 dBc/Hz
100 MHz Offset -162 dBc/Hz
Figure of Merit
Floor Integer Mode Normalized to 1 Hz -230 dBc/Hz
Floor Fractional Mode Normalized to 1 Hz -227 dBc/Hz
Flicker (Both Modes) Normalized to 1 Hz -268 dBc/Hz
VCO Characteristics
VCO Tuning Sensitivity at 4053 MHz Measured at 2.5 V 15 MHz/V
VCO Tuning Sensitivity at 3777 MHz Measured at 2.5 V 13 MHz/V
VCO Tuning Sensitivity at 3411 MHz Measured at 2.5 V 12 MHz/V
VCO Tuning Sensitivity at 2943 MHz Measured at 2.5 V 11.5 MHz/V
VCO Supply Pushing Measured at 2.5 V 2 MHz/V
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
6
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Figure 1. Typical Closed Loop Integer
Phase Noise[“Loop Filter Conguration Table”]
Figure 5. Typical VCO Sensitivity
-180
-160
-140
-120
-100
-80
-60
10
3
10
4
10
5
10
6
10
7
10
8
fout 3600 MHz, Loop BW 130 kHz, rms jitter 136 fs
fout 5600 MHz, Loop BW 130 kHz, rms jitter 116 fs
fout 8300 MHz, Loop BW 130 kHz, rms jitter 212 fs
fout 3600 MHz, Loop BW 250 kHz, rms jitter 86 fs
fout 5600 MHz, Loop BW 250 kHz, rms jitter 76 fs
fout 8300 MHz, Loop BW 250 kHz, rms jitter 98 fs
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
-180
-160
-140
-120
-100
-80
-60
-40
10
3
10
4
10
5
10
6
10
7
10
8
4053 MHz
3777 MHz
3411 MHz
2943 MHz
OFFSET (Hz)
PHASE NOISE (dBc/Hz)
Figure 2. Typical Closed Loop Fractional
Phase Noise [“Loop Filter Conguration Table”]
Figure 3. Free Running Phase Noise at f0 Figure 4. Free Running VCO
Phase Noise vs. Temperature
0
1
2
3
4
5
2700 2900 3100 3300 3500 3700 3900 4100 4300
TUNE VOLTAGE AFTER CALIBRATION (V)
VCO FREQUENCY(MHz)
fmin fmax
-180
-160
-140
-120
-100
-80
-60
10
3
10
4
10
5
10
6
10
7
10
8
fout 3605 MHz, Loop BW 130 kHz, rms jitter 145 fs
fout 5605 MHz, Loop BW 130 kHz, rms jitter 123 fs
fout 8305 MHz, Loop BW 130 kHz, rms jitter 227 fs
fout 3605 MHz, Loop BW 250 kHz, rms jitter 110 fs
fout 5605 MHz, Loop BW 250 kHz, rms jitter 95 fs
fout 8305 MHz, Loop BW 250 kHz, rms jitter 112 fs
OFFSET (Hz)
PHASE NOISE (dBc/Hz)
0
10
20
30
40
50
60
70
012345
4053 MHz at 2.5V, Tuning Cap 7
3777 MHz at 2.5V, Tuning Cap 7
3411 MHz at 2.5V, Tuning Cap 15
2943 MHz at 2.5V, Tuning Cap 15
TUNING VOLTAGE (V)
kVCO (MHz/V)
Figure 6. Typical Tuning Voltage
After Calibration at f0
-180
-160
-140
-120
-100
-80
10 100 1000 10000
27C
-40C
85C
PHASE NOISE (dBc/Hz)
FREQUENCY (MHz)
100 MHz Offset
1 MHz Offset
100 kHz Offset
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
7
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Figure 7. Integrated RMS Jitter[1]
[1] RMS Jitter data is measured in fractional mode with 250 kHz Loop bandwidth using 100 MHz reference, PD 50 MHz. Integration bandwidth from
1 kHz to 100 MHz.
[2] Measured fro m a 50  sour ce with a 100  external resistor ter minat ion. Se e PLL with Integr ated RF VCOs Operat ing Gui de Reference Input Stag e section
for more details. Full FOM performance up to maximum 3.3 Vpp input voltage.
[3] Measured from a 50  source with a 100  external resistor termination. See PLL with Integrated RF VCOs Operating Guide Reference Input
Stage section for more details. Full FOM performance up to maximum 3.3 Vpp input voltage.
40
60
80
100
120
140
160
180
200
10 100 1000 10000
-40C
27C
85C
RMS JITTER (fs)
FREQUENCY (MHz)
-240
-230
-220
-210
-200
10
2
10
3
10
4
10
5
10
6
NORMALIZED PHASE NOISE (dBc/Hz)
FREQUENCY OFFSET (Hz)
FOM Floor
FOM 1/f Noise
Typ FOM vs Offset
Figure 8. Figure of Merit
Figure 9. Typical Output Power vs.
Temperature, Maximum Gain Figure 10. RF Output Return Loss
-235
-230
-225
-220
-215
-15 -10 -5 0 5 10
14 MHz sq
25 MHz sq
50 MHz sq
100 MHz sq
FLOOR FOM (dBc/Hz)
REFERENCE POWER (dBm)
100 MHz
14 MHz
50 MHz
25 MHz
Figure 12. Reference Input Sensitivity,
Square Wave, 50 [2]
-15
-10
-5
0
5
10
0 1000 2000 3000 4000 5000 6000 7000 8000
27 C
-40 C
85 C
OUTPUT POWER (dBm)
OFFSET (MHz)
Figure 11. Reference Input Sensitivity
Sinusoid Wave, 50 [3]
-235
-230
-225
-220
-215
-210
-205
-200
-20 -15 -10 -5 0 5
REFERENCE POWER (dBm)
FLOOR FOM (dBc/Hz)
14 MHz
25 MHz
50 MHz
100 MHz
-30
-25
-20
-15
-10
-5
0
100 1000 10000
FREQUENCY (MHz)
RETURN LOSS(dB)
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
8
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Figure 13. Integer Boundary Spur at
3600.2 MHz[4]
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
10
3
10
4
10
5
10
6
10
7
10
8
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
10
3
10
4
10
5
10
6
10
7
10
8
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
[4] Fractional Mode Mode B, Integer Boundary Spur, Loop Filter bandwidth 130 kHz, REF in 100 MHz, 50 MHz PD
[5] REF in 100 MHz, 50 MHz PD, Output Divider 4 Selected, Loop Filter bandwidth 130 kHz, Channel Spacing 100 kHz
[6] Exact Frequency Mode, REF in 100 MHz, 50 MHz PD, Output Divider 2 Selected, Loop Filter bandwidth = 130 kHz, Channel Spacing = 100 kHz
[7] Exact Frequency Mode, Channel Spacing 100 kHz, RF out = 3951 MHz, REF in 100 MHz, 50 MHz PD, Output Divider 1 selected, Loop Filter
bandwidth 130 kHz,
[8] Fractional Mode B, RF out 3591 MHz, REF in 100 MHz, 50 MHz PD, Output Divider 1 selected, Loop Filter bandwidth 130 kHz.
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
10
3
10
4
10
5
10
6
10
7
10
8
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
10
3
10
4
10
5
10
6
10
7
10
8
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
Figure 14. Integer Boundary Spur at
8300.8 MHz[4]
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
10
3
10
4
10
5
10
6
10
7
10
8
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
Figure 15. Integer-N, Exact Frequency
Mode ON, Performance at 900 MHz[5]
Figure 16. Fractional-N, Exact Frequency
Mode ON, Performance at 1813.5 MHz[6]
Figure 17. Fractional-N, Exact Frequency
Mode ON, Performance at 3591 MHz[7]
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
10
3
10
4
10
5
10
6
10
7
10
8
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
Figure 18. Fractional-N, Exact Frequency
Mode OFF, Performance at 3591 MHz[8]
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
9
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Loop Filter
BW (kHz)
C1
(pF)
C2
(nF)
C3
(pF)
C4
(pF)
R2
(k)
R3
(k)
R4
(k) Loop Filter Design
130 100 8.2 120 120 11.2 1.2
250 150 3.3 18 18 2.2 1 1
Loop Filter Conguration Table
Figure 19. Worst Spur, Fixed 50 MHz
Reference, Output Freq. = 3900.1 MHz[9]
-180
-160
-140
-120
-100
-80
-60
-40
10
2
10
3
10
4
10
5
10
6
10
7
10
8
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
Figure 20. Worst Spur, Tunable Reference
47.5 MHz, Output Frequency = 3900.1 MHz [9]
-180
-144
-108
-72
-36
0
102103104105106107108
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
Figure 21. Worst Spur, Fixed vs. Tunable
Reference [10]
-110
-100
-90
-80
-70
-60
-50
3.9GHz +10
3
Hz 3.9GHz +10
4
Hz 3.9GHz +10
5
Hz 3.9GHz +10
6
Hz 3.9GHz +10
7
Hz
Fixed 50 MHz Reference
Tunable Reference
WORST SPUR (dBc)
OUTPUT FREQUENCY
[9] Capability of HMC834LP6GE to generate low frequencies (as low as 45 MHz), enables the HMC834LP6GE to be used as a tunable reference
source into another Hittite PLL. This maximizes spur performance of Hittite PLLs. Please see “HMC834LP6GE Application Information” for more
information.
[10] The graph is generated by observing, and plotting, the magnitude of only the worst spur (largest magnitude), at any offset, at each output
frequency, while using a xed 50 MHz reference and a tunable reference tuned to 47.5 MHz. See “HMC834LP6GE Application Information” for
more details.
[11] Phase noise performance of the HMC834LP6GE when used as a tunable reference source. HMC834LP6GE is operating at 4.2 GHz/42,
4.2 GHz/56, and 2.8 GHz/62 for the 100 MHz, 75 MHz, and 45.16129 MHz curves respectively, using a second order loop lter with 230 kHz
bandwidth.
Figure 22. Low Frequency Performance [11]
-170
-160
-150
-140
-130
-120
10
2
10
3
10
4
10
5
10
6
10
7
10
8
Carrier Frequency 45.16129 MHz
Carrier Frequency = 75 MHz
Carrier Frequency = 100 MHz
PHASE NOISE (dBc/Hz)
OFFSET (Hz)
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
10
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Pin Descriptions
Pin Number Function Description
1AVDD DC Power Supply for analog circuitry.
2, 5, 6, 8, 9,
11 - 14, 18 - 22, 24,
26, 29, 34, 37, 38
N/C The pins are not connected internally; however, all data shown herein
was measured with these pins connected to RF/DC ground externally.
3VPPCP Power Supply for charge pump analog section
4CP Charge Pump Output
7VDDLS Power Supply for the charge pump digital section
10 RVDD Reference Supply
15 XREFP Reference Oscillator Input
16 DVDD3V DC Power Supply for Digital (CMOS) Circuitry
17 CEN Chip Enable. Connect to logic high for normal operation.
23 VTUNE VCO Varactor. Tuning Port Input.
25 VCC2 VCO Analog Supply 2
27 VCC1 VCO Analog Supply 1
28 RF_ N RF Negative Output (On in differential and single-ended conguration)
30 SEN PLL Serial Port Enable (CMOS) Logic Input
31 SDI PLL Serial Port Data (CMOS) Logic Input
32 SCK PLL Serial Port Clock (CMOS) Logic Input
33 LD_SDO Lock Detect, or Serial Data, or General Purpose (CMOS) Logic Output (GPO)
35 VCCHF DC Power Supply for Analog Circuitry
36 VCCPS DC Power Supply for Analog Prescaler
39 VCCPD DC Power Supply for Phase Detector
40 BIAS
External bypass decoupling for precision bias circuits.
Note: 1.920V ±20mV reference voltage (BIAS) is generated internally and cannot
drive an external load. Must be measured with 10G meter such as Agilent 34410A,
normal 10M DVM will read erroneously.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
11
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Outline Drawing
Part Number Package Body Material Lead Finish MSL Rating Package Marking [1]
HMC834LP6GE RoHS-compliant Low Stress Injection Molded Plastic 100% matte Sn MSL1 H834
XXXX
[1] 4-Digit lot number XXXX
Package Information
NOTES:
1. PACKAGE BODY MATERIAL: LOW STRESS INJECTION MOLDED PLASTIC SILICA
AND SILICON IMPREGNATED.
2. LEAD AND GROUND PADDLE MATERIAL: COPPER ALLOY.
3. LEAD AND GROUND PADDLE PLATING: 100% MATTE TIN.
4. DIMENSIONS ARE IN INCHES [MILLIMETERS].
5. LEAD SPACING TOLERANCE IS NON-CUMULATIVE.
6. PAD BURR LENGTH SHALL BE 0.15mm MAX. PAD BURR HEIGHT SHALL BE 0.25mm
MAX.
7. PACKAGE WARP SHALL NOT EXCEED 0.05mm.
8. ALL GROUND LEADS AND GROUND PADDLE MUST BE SOLDERED TO PCB RF
GROUND.
9. REFER TO HITTITE APPLICATION NOTE FOR SUGGESTED PCB LAND PATTERN.
Absolute Maximum Ratings
AVDD, RVDD, DVDD3V, VCCPD,
VCCHF, VCCPS -0.3V to +3.6V
VPPCP, VDDLS, VCC1, VCC2 -0.3V to +5.5V
Operating Temperature -40°C to +85°C
Storage Temperature -65°C to 150°C
Maximum Junction Temperature 125 °C
Thermal Resistance (RTH)
(junction to ground paddle) 20 °C/W
Reow Soldering
Peak Temperature 260°C
Time at Peak Temperature 40 sec
ESD Sensitivity (HBM) Class 1B
Stresses above those listed under Absolute Maximum
Ratings may cause permanent damage to the device.
This is a stress rating only; functional operation of the
device at these or any other conditions above those
indicated in the operational section of this specication
is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device
reliability.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
12
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Evaluation PCB Schematic
The circuit board used in the application should use RF circuit design techniques. Signal lines should have
50 Ohm impedance while the package ground leads and exposed paddle should be connected directly to the
ground plane similar to that shown. A sufficient number of via holes should be used to connect the top and
bottom ground planes. The evaluation circuit board shown is available from Hittite upon request.
To view this Evaluation PCB Schematic please visit www.hittite.com and choose HMC834LP6GE from the
“Search by Part Number” pull down menu to view the product splash page.
Evaluation PCB
Item Contents Part Number
Evaluation PCB Only HMC834LP6GE Evaluation PCB EVAL01-HMC834LP6GE
Evaluation Kit
HMC834LP6GE Evaluation PCB
USB Interface Board
6’ USB A Male to USB B Female Cable
CD ROM (Contains User Manual, Evaluation PCB Schematic, Evaluation Software,
Hittite PLL Design Software)
EKIT01-HMC834LP6GE
Evaluation Order Information
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
13
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
HMC834LP6GE Application Information
Large bandwidth, industry leading phase noise and spurious performance, excellent noise oor (<-170 dBc/Hz),
coupled with a high level of integration make the HMC834LP6GE ideal for a variety of applications; as an RF or IF
stage LO, a clock source for high-frequency data-converters, or a tunable reference source for extremely low spurious
applications (~ -100 dBc/Hz spurs).
Figure 23. HMC834LP6GE in a typical transmit chain
Figure 24. HMC834LP6GE in a typical receive chain
Figure 25. HMC834LP6GE used as a tunable reference for second HMC834LP6GE
Using the HMC834LP6GE with a tunable reference as shown in Figure 25, it is possible to drastically improve spurious
emissions performance across all frequencies. Example shown in Figure 21 graph shows that it is possible to have
spurious emissions ~ -100 dBc/Hz across all frequencies. For more information about spurious emissions, how they
are related to the reference frequency, and how to tune the reference frequency for optimal spurious performance
please see the “Spurious Performance” section of Hittite PLL w/ Integraged VCOs Operating Guide. Note that at very
low output frequencies < 100 MHz, harmonics increase due to small internal AC coupling. Applications which are
sensitive to harmonics may require external low pass ltering.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
14
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
The output of the HMC834LP6GE is matched to 50  across all output frequencies from 45 MHz to 8400 MHz with
gap. As a result of the wideband 50  match, the output power of the HMC834LP6GE decreases with increas-
ing output frequency, as shown in Figure 9. If required, it is possible to adjust the output stage gain setting of the
HMC834LP6GE (“VCO_Reg 02h Biases”) at various operating frequencies in order to achieve a more constant
output power level across the frequency operating range of the HMC834LP6GE. An example is shown in Figure 26.
Figure 26.Reducing the output power variation of HMC834LP6GE across frequency by adjusting output stage gain
control.
If a higher output power than that shown in Figure 26 is required, it is possible to follow the HMC834LP6GE output
stage with a simple amplier such as H M C311SC70E in order to achieve a constant and high output power level
across the entire operating range of the HMC834LP6GE.
Output gain setting for Optimal Power Flatness
-20
-10
0
10
0 1000 2000 3000 4000 5000 6000 7000 8000
OUTPUT POWER (dBm)
OUTPUT FREQUENCY (MHz)
Gain = 0 dB
Gain = 9 dB
Gain = 3 dB
Divider output
stage gain = 3 dB
(VCO_Reg02h[8] = 1)
Gain = 0 dB
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
15
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.0 Theory of Operation
HMC834LP6GE is targeted for ultra low phase noise applications and has been designed with very low
noise reference path, phase detector and charge pump.
The HMC834LP6GE consists of the following functional blocks:
1. Reference Path Input Buffers and ’R’ Divider
2. VCO Path Input Buffer and Multi-Modulus ’N’ Divider
3. ∆∑ Fractional Modulator
4. Phase Detector
5. Charge Pump
6. Serial Port with Read Write Capability
7. General Purpose Output (GPO) Port
8. Power On Reset Circuit
9. VCO Subsystem
10. Built-In Self Test Features
1.1 VCO Subsystem
The HMC834LP6GE contains a VCO subsystem that can be congured to operate in:
• Fundamental frequency (fo) mode (2800 MHz to 4200 MHz).
• Divide by N (fo/N), where N = 1,2,4,6,8...58,60,62 mode (45 MHz to 1400 MHz and 1400 MHz to
2100 MHz with gap).
• Doubler (2fo) mode (5600 MHz to 8400 MHz).
All modes are VCO register programmable as shown in Figure 27. One loop lter design can be used for
the entire frequency of operation of the HMC834LP6GE.
Figure 27. PLL and VCO Subsystems
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
16
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.2 VCO Calibration
1.2.1 VCO Auto-Calibration (AutoCal)
HMC834LP6GE uses a step tuned type VCO. A simplied step tuned VCO is shown in Figure 28. A step
tuned VCO is a VCO with a digitally selectable capacitor bank allowing the nominal center frequency of the
VCO to be adjusted or ‘stepped’ by switching in/out VCO tank capacitors. A more detailed view of a typical
VCO subsystem conguration is shown in Figure 29. A step tuned VCO allows the user to center the VCO
on the required output frequency while keeping the varactor tuning voltage optimized near the mid-voltage
tuning point of the HMC834LP6GE’s charge pump. This enables the PLL charge pump to tune the VCO
over the full range of operation with both a low tuning voltage and a low tuning sensitivity (kvco).
The VCO switches are normally controlled automatically by the HMC834LP6GE using the
Auto-Calibration feature. The Auto-Calibration feature is implemented in the internal state machine. It
manages the selection of the VCO sub-band (capacitor selection) when a new frequency is programmed.
The VCO switches may also be controlled directly via register Reg 05h for testing or for other special
purpose operation. Other control bits specic to the VCO are also sent via Reg 05h.
Figure 28. Simplied Step Tuned VCO
Figure 29. HMC834LP6GE PLL and VCO Subsystems
To use a step tuned VCO in a closed loop, the VCO must be calibrated such that the HMC834LP6GE
knows which switch position on the VCO is optimum for the desired output frequency. The HMC834LP6GE
supports Auto-Calibration (AutoCal) of the step tuned VCO. The AutoCal xes the VCO tuning voltage
at the optimum mid-point of the charge pump output, then measures the free running VCO frequency
while searching for the setting which results in the free running output frequency that is closest to the
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
17
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
desired phase locked frequency. This procedure results in a phase locked oscillator that locks over
a very narrow voltage range on the varactor. A typical tuning curve for a step tuned VCO is shown in
Figure 30. Note how the tuning voltage stays in a narrow range over a wide range of output frequencies.
0
1
2
3
4
5
920 960 1000 1040 1080 1120 1160
CALIBRATION FREQUENCY (MHz)
TUNE VOLTAGE AFTER CALIBRATION (V)
50MHz PFD, 500kHz Tuning Steps, +25C
256 Count Calibration ,195kHz Resolution
31usec Total Cal Time
015
31
Figure 30. A Typical 5-Bit 32 Switch VCO Tuning Voltage After Calibration
The calibration is normally run automatically once for every change of frequency. This ensures optimum
selection of VCO switch settings vs. time and temperature. The user does not normally have to be concerned
about which switch setting is used for a given frequency as this is handled by the AutoCal routine. The
accuracy required in the calibration affects the amount of time required to tune the VCO. The calibration
routine searches for the best step setting that locks the VCO at the current programmed frequency, and
ensures that the VCO will stay locked and perform well over it’s full temperature range without additional
calibration, regardless of the temperature that the VCO was calibrated at.
Auto-Calibration can also be disabled allowing manual VCO tuning. Refer to section 1.2.2 for a description
of manual tuning
1.2.1.1 AutoCal Use of Reg05h
AutoCal transfers switch control data to the VCO subsystem via Reg 05h. The address of the VCO
subsystem in Reg 05h is not altered by the AutoCal routine. The address and ID of the VCO subsystem
in Reg 05h must be set to the correct value before AutoCal is executed. For more information see section
1.19.
1.2.1.2 Auto-reLock on Lock Detect Failure
It is possible by setting Reg 07h[13] to have the VCO subsystem automatically re-run the calibration
routine and re-lock itself if Lock Detect indicates an unlocked condition for any reason. With this option the
system will attempt to re-Lock only once. Auto-reLock is recommended.
1.2.2 Manual VCO Calibration for Fast Frequency Hopping
If it is desirable to switch frequencies very quickly it is possible to eliminate the AutoCal time by calibrating
the VCO in advance and storing the switch number vs frequency information in the host. This can be done
by initially locking the PLL with Integrated VCO on each desired frequency using AutoCal, then reading,
and storing the VCO switch settings selected. The VCO switch settings are available in Reg 10h[7:0] after
every AutoCal operation. The host must then program the VCO switch settings directly when changing
frequencies. Manual writes to the VCO switches are executed immediately as are writes to the integer and
fractional registers when AutoCal is disabled. Hence frequency changes with manual control and AutoCal
disabled, requires a minimum of two serial port transfers to the PLL, once to set the VCO switches, and
once to set the PLL frequency.
If AutoCal is disabled Reg 0Ah[11]=1, the VCO will update its registers with the value written via Reg 05h
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
18
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
immediately. The VCO internal transfer requires 16 VSCK clock cycles after the completion of a write to
Reg 05h. VSCK and the AutoCal controller clock are equal to the input reference divided by 0, 4,16 or 32
as controlled by Reg 0Ah[14:13].
1.2.2.1 Registers required for Frequency Changes in Fractional Mode
A large change of frequency, in fractional mode (Reg 06h[11]=1), may require Main Serial Port writes to:
1. the integer register intg, Reg 03h (only required if the integer part changes)
2. the VCO SPI register, Reg 05h
• required for manual control of VCO if Reg 0Ah[11]=1 (AutoCal disabled)
• required to change the RF Divider value if needed (VCO_Reg 02h)
• required to turn on/off the doubler mode if needed (VCO_Reg 03h[0])
3. the fractional register, Reg 04h. The fractional register write triggers AutoCal if Reg 0Ah[11]= 0, and
is loaded into the modulator automatically after AutoCal runs. If AutoCal is disabled, Reg 0Ah[11]=1,
the fractional frequency change is loaded into the modulator immediately when the register is written
with no adjustment to the VCO.
Small steps in frequency in fractional mode, with AutoCal enabled (Reg 0Ah[11]= 0), usually only require a
single write to the fractional register. Worst case, 5 Main Serial Port transfers to the HMC834LP6GE could
be required to change frequencies in fractional mode. If the frequency step is small and the integer part of
the frequency does not change, then the integer register is not changed. In all cases, in fractional mode, it
is necessary to write to the fractional register Reg 04h for frequency changes.
1.2.2.2 Registers Required for Frequency Changes in Integer Mode
A change of frequency, in integer mode (Reg 06h[11]= 0), requires Main Serial Port writes to:
1. VCO SPI register, Reg 05h
• required for manual control of VCO if Reg 0Ah[11]=1 (AutoCal disabled)
• required to change the RF Divider value if needed (VCO_Reg 02h)
• required to turn on/off the doubler mode if needed (VCO_Reg 03h[0])
2. the integer register Reg 03h.
• In integer mode, an integer register write triggers AutoCal if Reg 0Ah[11]= 0, and is loaded into
the prescaler automatically after AutoCal runs. If AutoCal is disabled, Reg 0Ah[11]=1, the integer
frequency change is loaded into the prescaler immediately when written with no adjustment
to the VCO. Normally changes to the integer register cause large steps in the VCO frequency,
hence the VCO switch settings must be adjusted. AutoCal enabled is the recommended method
for integer mode frequency changes. If AutoCal is disabled (Reg 0Ah[11]=1), a priori knowledge
of the correct VCO switch setting and the corresponding adjustment to the VCO is required
before executing the integer frequency change.
1.2.3 VCO AutoCal on Frequency Change
Assuming Reg 0Ah[11]= 0, the VCO calibration starts automatically whenever a frequency change is
requested. If it is desired to rerun the AutoCal routine for any reason, at the same frequency, simply rewrite
the frequency change with the same value and the AutoCal routine will execute again without changing
nal frequency.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
19
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.2.4 VCO AutoCal Time & Accuracy
The VCO frequency is counted for Tmmt, the period of a single AutoCal measurement cycle.
Tmmt = Txtal · R · 2n(EQ 1)
n is set by Reg 0Ah[2:0] and results in measurement periods which are multiples of the PD
period, TxtalR.
R is the reference path division ratio currently in use, Reg 02h
Txtal is the period of the external reference (crystal) oscillator.
The VCO AutoCal counter will, on average, expect to register N counts, rounded down (oor) to the nearest
integer, every PD cycle.
N is the ratio of the target VCO frequency, fvco, to the frequency of the PD, fpd, where N can
be any rational number supported by the N divider.
N is set by the integer (Nint = Reg 03h) and fractional (Nfrac = Reg 04h) register contents
N = Nint + Nfrac / 224 (EQ 2)
The AutoCal state machine and the data transfers to the internal VCO subsystem SPI (VSPI) run at the rate
of the FSM clock, TFSM, where the FSM clock frequency cannot be greater than 50 MHz.
TFSM = Txtal · 2m(EQ 3)
m is 0, 2, 4 or 5 as determined by Reg 0Ah[14:13]
The expected number of VCO counts, V, is given by
V = oor (N · 2n)(EQ 4)
The nominal VCO frequency measured, fvcom, is given by
fvcom = V · fxtal / (2n · R) (EQ 5)
where the worst case measurement error, ferr , is:
ferr ≈ ±fpd / 2n + 1 (EQ 6)
Figure 31. VCO Calibration
A 5-bit step tuned VCO, for example, nominally requires 5 measurements for calibration, worst case
6 measurements, and hence 7 VSPI data transfers of 20 clock cycles each. The measurement has a
programmable number of wait states, k, of 100 FSM cycles dened by Reg 0Ah[7:6] = k. Hence total
calibration time, worst case, is given by:
Tcal = k100TFSM + 6TPD 2n + 7 · 20TFSM (EQ 7)
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
20
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
or equivalently
Tcal = Txtal (6R · 2n + (140+100k) · 2m)
where k = Reg 0Ah[7:6] decimal (EQ 8)
For guaranteed hold of lock, across temperature extremes, the resolution should be better than
1/8th the frequency step caused by a VCO sub-band switch change. Better resolution settings will show no
improvement.
1.2.4.1 VCO AutoCal Example
The VCO subsystem must satisfy the maximum fpd limited by the two following conditions:
a. N ≥ 16 (fint), N ≥ 20.0 (ffrac), where N = fVCO/ fpd
b. fpd ≤ 100 MHz
Suppose the VCO subsystem output frequency is to operate at 2.01 GHz. Our example crystal frequency
is fxtal = 50 MHz, R=1, and m=0 (Figure 31), hence TFSM = 20 ns (50 MHz). Note, when using AutoCal, the
maximum AutoCal Finite State Machine (FSM) clock cannot exceed 60 MHz (see Reg 0Ah[14:13]). The
FSM clock does not affect the accuracy of the measurement, it only affects the time to produce the result.
This same clock is used to clock the 16 bit VCO serial port.
If time to change frequencies is not a concern, then one may set the calibration time for maximum accuracy,
and therefore not be concerned with measurement resolution.
Using an input crystal of 50 MHz (R=1 and fpd=50 MHz) the times and accuracies for calibration using
(EQ 6) and (EQ 8) are shown in Table 1. Where minimal tuning time is 1/8th of the VCO band spacing.
Across all VCOs, a measurement resolution better than 800 kHz will produce correct results. Setting
m = 0, n = 5, provides 781 kHz of resolution and adds 8.6 µs of AutoCal time to a normal frequency hop.
Once the AutoCal sets the nal switch value, 8.64 µs after the frequency change command, the fractional
register will be loaded, and the loop will lock with a normal transient predicted by the loop dynamics. Hence
we can see in this example that AutoCal typically adds about 8.6 µs to the normal time to achieve frequ-
ency lock. Hence, AutoCal should be used for all but the most extreme frequency hopping requirements.
Table 1. AutoCal Example with Fxtal = 50 MHz, R = 1, m = 0
Control Value
Reg0Ah[2:0] n 2nTmmt
(µs)
Tcal
(µs) Ferr Max
0010.02 4.92 ± 25 MHz
1120.04 5.04 ± 12.5 MHz
2240.08 5.28 ± 6.25 MHz
3380.16 5.76 ± 3.125 MHz
4 5 32 0.64 8.64 ± 781 kHz
5 6 64 1.28 12.48 ± 390 kHz
6 7 128 2.56 20.16 ± 195 kHz
7 8 256 5.12 35.52 ± 98 kHz
1.2.5 VCO Output Mute Function
The output mute function enables the HMC834LP6GE to disable the VCO output while maintaining the PLL
and VCO subsystems fully functional. The mute function provides over 40 dB of isolation throughout the
operating range of the HMC834LP6GE. To mute the output of the HMC834LP6GE, the following register
writes are necessary:
1. VCO_Reg 03h [2] = 1, to place the VCO subsystem in manual mode
2. VCO_Reg 01h[2] = 1, to disable the VCO subsystem output buffer
3. VCO_Reg 01h [3] = 0, to disable the VCO subsystem limiter.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
21
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Please note that the VCO subsystem registers are not directly accessible. They are written to via PLL Reg
05h. More information about VCO subsystem SPI in section 1.19.
1.3 VCO Built in Test with AutoCal
The frequency limits of the VCO can be measured using the BIST features of the AutoCal machine.
This is done by setting Reg 0Ah[10]=1 which freezes the VCO switches in one position. VCO switches may
then be written manually, with the varactor biased at the nominal mid-rail voltage used for AutoCal. For
example to measure the VCO maximum frequency use switch 0, written to the VCO subsystem via Reg
05h=[000000000 0000 VCOID]. Where VCOID = ‘000’b.
If AutoCal is enabled, (Reg 0Ah[11] = 0), and a new frequency is written, AutoCal will run, but with switches
frozen. The VCO frequency error relative to the command frequency will be measured and results written
to Reg 11h[19:0] where Reg 11h[19] is the sign bit. The result will be written in terms of VCO count error
(EQ 4). For example if the expected VCO is 2 GHz, reference is 50 MHz, and n is 6, we expect to measure
2560 counts. If we measure a difference of -5 counts in R e g 11h, then it means we actually measured 2555
counts. Hence the actual frequency of the VCO is 5/2560 low, or 1.99609375 GHz, ±1 Count ~ ±781 kHz.
1.4 Spurious Performance
1.4.1 Integer Operation and Reference Spurious
The VCO always operates at an integer multiple of the PD frequency in an integer synthesizer. In general,
spurious signals originating from an integer synthesizer can only occur at multiples of the PD frequency.
These unwanted outputs closest to the carrier are often simply referred to as reference sidebands.
Unwanted reference harmonics can also exist far from the carrier due to circuit isolation.
Spurs unrelated to the reference frequency must originate from outside sources. External spurious sources
can modulate the VCO indirectly through power supplies, ground, or output ports, or bypass the loop lter
due to poor isolation of the lter. It can also simply add to the output of the PLL.
Reference spuri ous levels are typically below -100 dBc with a well designed board layout. A regulator with
low noise and high power supply rejection, such as the HMC1060LP3E, is recommended to minimize
external spurious sources.
Reference spurious levels of below -100 dBc require superb board isolation of power supplies, isolation of
the VCO from the digital switching of the synthesizer and isolation of the VCO load from the synthesizer.
Typical board layout, regulator design, eval boards and application information are available for very low
spurious operation. Operation with lower levels of isolation in the application circuit board, from those rec-
ommended by Hittite, can result in higher spurious levels.
If the application environment contains other interfering frequencies unrelated to the PD fre quency, and
if the application isolation from the board layout and regulation are insufficient, the unwanted interfering
frequencies will mix with the desired synthesizer output and cause additional spurious emissions. The
level of these emissions is dependant upon isolation and supply regulation or rejection (PSRR).
1.4.2 Fractional Operation and Spurious
Unlike an integer PLL, spurious signals in a fractional PLL can occur due to the fact that the VCO operates
at frequencies unrelated to the PD frequency. Hence intermodulation of the VCO and the PD harmonics
can cause spurious sidebands. Spurious emissions are largest when the VCO operates very close to an
integer multiple of the PD. When the VCO operates exactly at a harmonic of the PD then, no in-close mixing
products are present.
As shown in Figure 32, interference is always present at multiples of the PD frequency, fpd, and the VCO
frequency, fvco. The difference, ∆, between the VCO frequency and the nearest har monic of the reference,
will create what are referred to as integer boundary spurs. Depending upon the mode of operation of
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
22
HMC834LP6GE
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FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
the synthesizer, higher order, lower power spurs may also occur at multiples of integer fractions (sub-
harmonics) of the PD frequency. That is, fractional VCO frequencies which are near nfpd + fpdd/m, where n,
d and m are all integers and d<m (mathematicians refer to d/m as a rational num ber). We will refer to fpdd/m
as an integer fraction. The denominator, m, is the order of the spurious product. Higher values of m produce
smaller amplitude spurious at offsets of m∆ and usually when m>4 spurs are small or unmeasurable.
The worst case, in fractional mode, is when d=0, and the VCO frequency is offset from nfpd by less than
the loop bandwidth. This is the “in-band integer boundary” case.
Figure 32. Fractional Spurious Example
Characterization of the levels and orders of these products is not unlike a mixer spur chart. Exact levels
of the products are dependent upon isolation of the various synthesizer parts. Hittite can offer guidance
about expected levels of spurious with HMC834LP6GE evaluation boards. Regulators with high power
supply rejection ratios (PSRR) are recommended, especially in noisy applications.
1.4.2.1 Charge Pump and Phase Detector Spurious Considerations
Charge pump and phase detector linearity are of paramount importance when operating in fractional
mode. Any non-linearity degrades phase noise and spurious performance.
We dene zero phase error when the reference signal and the divider VCO signal arrive at the Phase
Detector at the same time. Phase detector linearity degrades when the phase error is very small and
when the random phase errors cause the phase detector to switch back an forth between reference lead
and VCO lead.
These switching non-linearities in fractional mode are eliminated by operating the phase detector with an
average phase offset such that either the reference or VCO always leads.
A programmable charge pump offset current source is used to add DC current to the loop lter and create
the desired phase offset. Positive current causes the VCO to lead, negative current causes the reference
to lead.
The offset charge pump is controlled via Reg 09h. The phase offset is scaled from 0 degrees, that is the
reference and the VCO path arrive in phase, to 360 degrees, where they arrive a full cycle late. The offset
can also be thought of in absolute time difference between the arrivals.
The recommended operating point for the charge pump in fractional mode is one where the time offset at
the phase detector is ~2.5ns + 4TVCO, where TVCO is the RF period at the fractional prescaler input. The
required CP offset current should never exceed 25% of the programmed CP current.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
23
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
The specic level of charge pump offset current Reg 09h[20:14] is determined by this time offset, the
comparison frequency and the charge pump current:
( )
( )
( )
9
2.5 10 4 sec ,0.25Required CP Offset min VCO comparison CP CP
T FI I
−

• +• • • •


=
where:
TVCO: is the RF period at the fractional prescaler input
ICP: is the full scale current setting of the switching charge pump Reg 09h[6:0] Reg 09h[13:7]
(EQ 9)
Operation with charge pump offset inuences the required conguration of the Lock Detect function. Refer
to the description of Lock Detect function in section 1.11. Note that this calculation can be performed for
the center frequency of the VCO, and does not need renement for small differences < 25 % in center
frequencies.
Another factor in the spectral performance in Fractional Mode is the choice of the Delta-Sigma Modulator
mode. Mode A can offer better in-band spectral performance (inside the loop bandwidth) while Mode B
offers better out of band performance. See Reg 06h[3:2] for DSM mode selection. Finally, all fractional
synthesizers cre ate fractional spurs at some level. Hittite offers the lowest level fractional spurious in the
indus try in an integrated solution.
1.4.2.2 Spurious Related to Channel Step Size (Channel Spurs)
Many fractional PLLs also create spurious emissions at offsets which are multiples of the channel step
size. We refer to these as Channel Spurs. It is common in the industry to set the channel step size by use
of the so-called modulus. For example, channel step size of 100 kHz requires a small modulus related to
the step size, and often results in 100 kHz Channel Spurs.
The HMC834LP6GE uses a large xed modulus unrelated to the channel step size. As a result, the
HMC834LP6GE has extremely low or unmeasurable Channel Spurs. In addition Exact Frequency Mode
(1.12.2.2) allows exact channel step size with no Channel Spurs.
The lack of Channel Spurs means that the HMC834LP6GE has large regions of operation between Integer
Boundaries with little or no spurs of any kind. Large spurious free zones enable the HMC834LP6GE to
be used with a tunable reference, to effectively move the spur free zones and hence achieve spur-free
operation at all frequencies. The resulting PLL is virtually spur-free at all frequencies.
For more information see 1.4.2.3.
1.4.2.3 Spurious Reduction with Tunable Reference
Section 1.4.2 discussed fractional mode Integer Boundary spurious caused by VCO operation near
reference harmonics. It is possible, with Hittite fractional synthesizers, to virtually eliminate the integer
boundary spurious at a given VCO frequency by changing the frequency of the reference. The reference
frequency is normally generated by a crystal oscillator and is not tunable. However, Hittite wideband PLLs
with Integrated VCOs, including HMC834LP6GE, can be used as a high-quality tunable reference source,
as shown in Figure 33.
Figure 33. Tunable reference source
With the setup shown in Figure 33, the HMC834LP6GE is capable of operating across all of its frequency
range without sacricing phase noise, while virtually eliminating spurious emissions. Optimum operation
requires appropriate conguration of the two synthesizers to achieve this performance. Hittite apps-support
can assist with the required algorithms for ultra-low spurious tunable reference applications.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
24
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
An HMC830LP6GE tunable reference PLL typically uses a high frequency crystal reference for best
performance. Phase noise from the MC830LP6GE tunable reference output at 100 kHz offset varies typically
from -145 dBc at 100 MHz output to -157 dBc at 25 MHz output. This performance of HMC830LP6GE as
a tunable reference is equivalent to the phase noise of high performance crystal oscillators.
Figure 34. Phase noise performance of the HMC833LP6GE
-170
-160
-150
-140
-130
-120
0.1 1 10 100 1000 10000 100000
Carrier Frequency = 25 MHz
Carrier Frequency = 55.55 MHz
Carrier Frequency = 100 MHz
PHASE NOISE (dBc/Hz)
OFFSET (kHz)
when used with a tunable reference source.
(HMC833LP6GE operating at 3 GHz/30, 3 GHz/54, and 1.55 GHz/62 for the 100 MHz, 55.55 MHz, and 25 MHz
curves respectively.)
Worst case spurious levels (largest spurs at any offset) of conventional xed reference vs. a tunable
reference can be compared by multiple individual phase noise measurements and summarized on a single
plot vs. carrier frequency.
For example, Figure 35 shows the spectrum of a carrier operating at 2000.1 MHz with a 50 MHz xed
reference. This case is 100 kHz away from an Integer Boundary (50 MHz x 40). Worst case spurious can
be observed at 100 kHz offset and about -52 dBc in magnitude.
Figure 36 shows the same HMC834LP6GE PLL VCO operating at the same 2000.1 MHz carrier frequency,
using a tunable reference at 47.5 MHz generated by HMC830LP6GE. Worst case spurious in this case can
be observed at 5 MHz offset and about -100 dBc in magnitude.
The results of Figure 35 and Figure 36 show that the tunable reference source achieves 50 dB better
spurious performance, while maintaining essentially the same phase noise performance.
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
0.1 1 10 100 1000 10000 100000
PHASE NOISE (dBc/Hz)
OFFSET (kHz)
(A)
2000.1 MHz Carrier frequency
Worst spur at 100 kHz offset
at ~-52 dBc with 50 MHz
crystal
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
0.1 1 10 100 1000 10000 100000
PHASE NOISE (dBc/Hz)
OFFSET (kHz)
(B)
2000.1 MHz Carrier frequency
Worst spur at 5 kHz offset
at -100 dBc with tunable
crystal
Figure 35. HMC834LP6GE Worst spur at any offset,
xed 50 MHz reference, output frequency = 2000.1
MHz
Figure 36. HMC834LP6GE worst spur at any
offset, tunable reference (HMC830LP6GE), output
frequency = 2000.1 MHz
Many spurious measurements, such as the ones in Figure 35 and Figure 36 can be summarized into a
single plot of worst case spurious at any offset vs. carrier frequency as shown in Figure 37. A log frequency
display relative to the 2000 MHz xed reference Integer Boundary was used to emphasize the importance
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
25
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
of the loop bandwidth on spurious performance of the xed reference case. This technique clearly shows
the logarithmic roll-off of the worst case spurious when operating near the Integer Boundary. In this case
the loop lter bandwidth of the HMC834LP6GE was 100 kHz.
Figure 37.
-120
-110
-100
-90
-80
-70
-60
-50
2GHz +1kHz 2GHz +10kHz 2GHz +100kHz 2GHz +1000kHz
2GHz +10000kHz
Fixed 50 MHz Reference
Tunable Reference
WORST SPUR (dBc)
OUTPUT FREQUENCY
(A)
(B)
Largest observed spurious, at any offset, using a xed 50 MHz reference source and a tunable
reference source.
For example worst case spurious operating at 2000.1 MHz (point (A)) in Figure 35 with a xed 50 MHz
reference) is represented by a single point in Figure 37 (point (A)) on the blue curve. Similarly, worst case
spurious from Figure 36 with variable reference, operating at 2000.1 MHz is represented by a single point
in Figure 37 (point (B)) on the green curve.
The plot in Figure 37 is generated by tuning the carrier frequency away from Integer Boundary and
recording the worst case spurious, at any offset, at each operating frequency. Figure 37 shows that the
worst case spurious for the 50 MHz xed reference case, is nearly constant between -51 dBc and -55
dBc when operating with a carrier frequency less than 100 kHz from the Integer Boundary (blue curve).
It also shows that the worst case spurious rolls off at about 25 dB/decade relative to 1 loop bandwidth.
For example, at an operating frequency of 2001 MHz (equivalent to 10 loop bandwidths offset) worst case
spurious is -80 dBc. Similarly, at an operating frequency of 2010 MHz (equivalent to 100 loop bandwidths)
worst case spurious is -100 dBc.
In contrast, the green curve of Figure 37 shows that the worst case spurious over the same operating
frequency range, when using an HMC830LP6GE tunable reference, is below -100 dBc at all operating
frequencies!
In general all fractional PLLs have spurious when operating near Integer Boundaries. High performance
tunable reference makes it possible to operate HMC834LP6GE, virtually spur-free at all frequencies, with
little or no degradation in phase noise.
1.5 Integrated Phase Noise & Jitter
The standard deviation of VCO signal jitter may be estimated with a simple approximation if it is assumed
that the locked VCO has a constant phase noise, o
| 2(fo), at offsets less than the loop 3 dB bandwidth and a
20 dB per decade roll-off at greater offsets. The simple locked VCO phase noise approximation is shown
on the left of Figure 38.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
26
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Figure 38. PLL with Integrated VCO Phase Noise & Jitter
With this simplication the total integrated VCO phase noise, o
| 2, in rads2 in the linear form is given by
o
| 2 = o
| 2 (fo) Bπ (EQ 10)
where o
| 2 (fo) is the single sideband phase noise in rads2/Hz inside the loop bandwidth, and B is the 3 dB
corner frequency of the closed loop PLL
The integrated phase noise at the phase frequency detector, o
| 2
pd is just scaled by N2
/N2
=
o
| 2
pd o
| 2 (EQ 11)
The rms phase jitter of the VCO in rads, o
| , is just the square root of the phase noise integral.
Since the simple integral of (EQ 10) is just a product of constants, we can easily do the integral in the log
domain. For example if the VCO phase noise inside the loop is -100 dBc/Hz at 10 kHz offset and the loop
bandwidth is 100 kHz, and the division ratio is 100, then the integrated phase noise at the phase frequency
detector, in dB, is given by:
o
| 2 = 10log ( o
| 2 (fo)Bπ/N2) = -100 + 50 + 5 - 40 = -85 dBc
pddB
or equivalently, o
| = 1 0 -85/20 = 53.6e-6 rads = 3.2e-3 degrees.
While the phase noise reduces by a factor of 20logN after division to the reference, due to the increased
period of the PD reference signal, the jitter is constant.
The rms jitter from the phase noise is then given by
Tjpn = Tpdo
| pd/2π (EQ 12)
In this example if the PD reference was 50 MHz, Tpd = 20ns, and hence Tjpn = 179 femto-sec.
It should be noted that this last expression is based upon a closed form integral of the entire spectrum of
the oscillator phase noise. This integral starts at DC. It is common for real system to evaluate jitter over
shorter intervals of time, hence the integral often starts at some nite frequency offset and will produce a
jitter that is less than that given by the full expression. Finally real oscillators have noise oors that also
contribute to jitter. The phase noise of a white noise oor is a simple integral of noise oor density times
bandwidth of interest to the system. This additional noise power should be added to the expression of
(EQ 16) to give a more accurate jitter number. Depending upon the bandwidth of the system in question
this noise oor contribution may be an important factor.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
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FRACTIONAL-N PLL WITH INTEGRATED VCO
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1.6 Reference Input Stage
Figure 39. Reference Path Input Stage
The reference buffer provides the path from an external reference source (generally crystal based) to
the R divider, and eventually to the phase detector. The buffer has two modes of operation controlled by
Reg 08h[21]. High Gain (Reg 08h[21] = 0), recommended below 200 MHz, and High frequency (Reg 08h[21]
= 1), for 200 to 350 MHz operation. The buffer is internally DC biased, with 100  internal termination. For
50  match, an external 100  resistor to ground should be added, followed by an AC coupling capacitor
(impedance < 1 ), then to the XREFP pin of the part.
At low frequencies, a relatively square reference is recommended to keep the input slew rate high. At higher
frequencies, a square or sinusoid can be used. The following table shows the recommended operating
regions for different reference frequencies. If operating outside these regions the part will normally still
operate, but with degraded reference path phase noise performance.
Minimum pulse width at the reference buffer input is 2.5 ns. For best spur performance when R = 1, the
pulse width should be (2.5ns + 8TPS), where TPS is the period of the VCO at the prescaler input. When R >
1 minimum pulse width is 2.5 ns.
Table 2. Reference Sensitivity Table
Square Input Sinusoidal Input
Reference Input
Frequency
(MHz)
Slew > 0.5V/ns Recommended Swing (Vpp) Recommended Power Range (dBm)
Recommended Min Max Recommended Min Max
< 10 YES 0.6 2.5 x x x
10 YES 0.6 2.5 x x x
25 YES 0.6 2.5 ok 8 15
50 YES 0.6 2.5 YES 6 15
100 YES 0.6 2.5 YES 5 15
150 ok 0.9 2.5 YES 4 12
200 ok 1. 2 2.5 YES 3 8
Input referred phase noise of the PLL when operating at 50 MHz is between -150 and -156 dBc/Hz at
10 kHz offset depending upon the mode of operation. The input reference signal should be 10 dB better
than this oor to avoid deg radation of the PLL noise contribution. It should be noted that such low levels
are only necessary if the PLL is the dominant noise contributor and these levels are required for the system
goals.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
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FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.7 Reference Path ’R’ Divider
The reference path “R” divider is based on a 14-bit counter and can divide input signals by values from 1
to 16,383 and is controlled by rdiv (Reg 02h).
Minimum pulse width at the reference buffer input is 2.5 ns. For best spur performance when R = 1, the
pulse width should be (2.5 ns + 8Tps), where Tps is the period of the VCO at the prescaler input. When R
> 1 minimum pulse width is 2.5 ns.
1.8 RF Path ’N’ Divider
The main RF path divider is capable of average divide ratios between 219-5 (524,283) and 20 in fractional
mode, and 219-1 (524,287) to 16 in integer mode. The VCO frequency range divided by the minimum N
divider value will place practical restrictions on the maximum usable PD frequency. For example a VCO
operating at 1.5 GHz in fractional mode with a minimum N divider value of 20 will have a maximum PD
frequency of 75 MHz.
1.9 Charge Pump & Phase Detector
The Phase detector (PD) has two inputs, one from the reference path divider and one from the RF path
divider. When in lock these two inputs are at the same average frequency and are xed at a constant
average phase offset with respect to each other. We refer to the frequency of operation of the PD as fpd.
Most formulae related to step size, delta-sigma modulation, timers etc., are functions of the operating
frequency of the PD, fpd. fpd is also referred to as the comparison frequency of the PD.
The PD compares the phase of the RF path signal with that of the reference path signal and controls the
charge pump output current as a linear function of the phase difference between the two signals. The
output current varies linearly over a full ±2π radians (±360°) of input phase difference.
1.10 Phase Detector Functions
Phase detector register Reg 0Bh allows manual access to control special phase detector features.
PD_up_en (Reg 0Bh[5]), if 0, masks the PD up output, which prevents the charge pump from pumping up.`
PD_dn_en (Reg 0Bh[6]), if 0, masks the PD down output, which prevents the charge pump from pumping
down.
Clearing both PD_up_en and PD_dn_en effectively tri-states the charge pump while leaving all other
functions operating internally.
PD Force UP Reg 0Bh[9] = 1 and PD Force DN Reg 0Bh[10] = 1 allows the charge pump to be forced up
or down respectively. This will force the VCO to the ends to the tuning range which can be useful in test
of the VCO.
1.11 Phase Detector Window Based Lock Detect
Lock Detect Enable Reg 07h[3]=1 is a global enable for all lock detect functions.
The window based Lock Detect circuit effectively measures the difference between the arrival of the
reference and the divided VCO signals at the PD. The arrival time difference must consistently be less
than the Lock Detect window length, to declare lock. Either signal may arrive rst, only the difference in
arrival times is counted.
1.11.1 Analog Window Lock Detect
The lock detect window may be generated by either an analog one shot circuit or a digital one shot based
upon an internal timer. Setting Reg 07h[6]=0 will result in a xed, analog, nominal 10 ns window, as shown
in Figure 40. The analog window cannot be used if the PD rate is above 50 MHz, or if the offset is too large.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
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FRACTIONAL-N PLL WITH INTEGRATED VCO
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Figure 40. Normal Lock Detect Window - Integer Mode, Zero Offset
For example a 25 MHz PD rate with a 1 mA charge pump setting (Reg 09h[6:0]=Reg 09h[13:7]= 32h) and
400 µA offset down current (Reg 09h[20:14]=50h Reg 09h[22]= 1), would have an offset of about 400/1000
= 40% of the PD period or about 16 ns. In such an extreme case the divided VCO would arrive 16 ns after
the PD reference, and would always arrive outside of the 10 ns lock detect window. In such a case the lock
detect circuit would always read unlocked, even though the VCO might be locked. When using the 10 ns
analog lock detect window, with a 40 ns PD period, the offset must always be less than 25% of the charge
pump setting, 20% to allow for tolerances. Hence a 1 mA charge pump setting can not use more than 200
µA offset with a 25 MHz PD and an analog Lock detect window. Charge pump current, charge pump offset,
phase detector rate and lock detect window are related.
1.11.2 Digital Window Lock Detect
Setting Reg 07h[6]=1 will result in a variable length lock detect window based upon an internal digital timer.
The timer period is set by the number of cycles of the internal LD clock as programmed by Reg 07h[9:7].
The LD clock frequency is adjustable by Reg 07h[11:10]. The LD clock signal can be viewed via the GPO
test pins. Refer 1.16 for details.
1.11.3 Declaration of Lock
wincnt_max in Reg 07h[2:0] denes the number of consecutive counts of the divided VCO that must land
inside the lock detect window to declare lock. If for example we set wincnt_max = 2048, then the VCO
arrival would have to occur inside the window 2048 times in a row to be declared locked, which would
result in a Lock Detect Flag high. A single occurrence outside of the window will result in an out of lock, i.e.
Lock Detect Flag low. Once low, the Lock Detect Flag will stay low until the wincnt_max = 2048 condition
is met again.
The Lock Detect Flag status is always readable in Reg 12h[1], if locked = 1. Lock Detect status is also
output to the LD_SDO pin if Reg 0Fh[4:0]=1. Again, if locked, LD_SDO will be high. Setting Reg 0Fh[6]=0
will display the Lock Detect Flag on LD_SDO except when a serial port read is requested, in which case
the pin reverts temporarily to the Serial Data Out pin, and returns to the Lock Detect Flag after the read is
completed. Refer to 1.11.5 for Timing of the Lock Detect information.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
30
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FRACTIONAL-N PLL WITH INTEGRATED VCO
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1.11.4 Phase Offset & Fractional Linearity
When operating in fractional mode the linearity of the charge pump and phase detector are much more
critical than in integer mode. The phase detector linearity is degraded when operating with zero phase
offset. Hence in fractional mode it is necessary to offset the phase of the PD reference and the VCO at the
phase detector. In such a case, for example with an offset delay, as shown in Figure 41, the VCO arrival will
always occur after the reference. The lock detect circuit window may need to be adjusted to allow for the
delay being used. for details see section “Digital Lock Detect with Digital Window Example”.
Figure 41. Lock Detect Window - Fractional Mode with Offset
1.11.5 Digital Lock Detect with Digital Window Example
Typical Digital Lock detect window widths are shown in Table 3. Lock Detect windows typically vary ±10%
vs voltage and ±25% over temperature (-40°C to +85°C).
Table 3. Typical Digital Lock Detect Window
LD Timer Speed
Reg07[11:10]
Digital Lock Detect Window
Nominal Value ±25% (ns)
Fastest 00 6.5 811 17 29 53 100 195
01 78.9 12.8 21 36 68 130 255
10 1.7 9.2 13.3 22 38 72 138 272
Slowest 11 7.6 10.2 15.4 26 47 88 172 338
LD Timer Divide Setting
Reg07[9:7] 01234567
LD Timer
Divide Value 0.5 124816 32 64
As an example, in fractional mode, with a 50 MHz PD, with a Charge pump gain of 2 mA and a Down
Leakage of -400 µA (Reg 09h[13:7] = 64h, Reg 09h[6:0] = 64h, Reg 09h[20:14] = 50h, Reg 09h[22] = 1),
the average offset at the PD will be -0.400/2 = 0.2 of the PD period, or about 4 ns ±25%. Hence, when in
lock, the divided VCO will arrive at the PD about 4 ns after the divided Reference. The Lock Detect Window
always starts on the arrival of the rst signal at the PD, in this case the Reference. The Lock Detect window
must be longer than 4 ns + 25% and shorter than the period of the PD, in this example, 20 ns. A perfect
Lock Detect window would be the geometric mean or 9.8 ns.
A comfortable solution of 12.8 ns with timer speed set at Reg 07h[11:10]=1 and Timer divider Reg
07h[9:7]=2 works well for the example PD frequency and charge pump offset setting.
Tolerance on the window is +25% at +85 °C, -25% at -40 °C. Here 12.8 ns nominal window may extend
by +25% at +85°C to 16 ns, which is ne for a PD period of 20 ns. Also the minimum window may shrink by
25% to 9.6 ns at -40°C, which again works well for the worst case offset of 4.6 ns.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
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Figure 42. Lock Detect Window Example with 50 MHz PD and 3.9 ns VCO Offset
There is always a good solution for the lock detect window for a given operating point. The user should
understand however that one solution does not t all operating points. If charge pump offset or PD frequency
are changed signicantly then the lock detect window may need to be adjusted.
1.11.6 Cycle Slip Prevention (CSP)
When changing VCO frequency and the VCO is not yet locked to the reference, the instantaneous
frequencies of the two PD inputs are different, and the phase difference of the two inputs at the PD varies
rapidly over a range much greater than ±2π radians. Since the gain of the PD varies linearly with phase
up to ±2π, the gain of a conventional PD will cycle from high gain, when the phase difference approaches
a multiple of 2π, to low gain, when the phase difference is slightly larger than a multiple of 0 radians. The
output current from the charge pump will cycle from maximum to minimum even though the VCO has not
yet reached its nal frequency.
The charge on the loop lter small cap may actually discharge slightly during the low gain portion of the
cycle. This can make the VCO frequency actually reverse temporarily during locking. This phenomena is
known as cycle slipping. Cycle slipping causes the pull-in rate during the locking phase to vary cyclically.
Cycle Slipping increases the time to lock to a value greater than that predicted by normal small signal
Laplace analysis.
The synthesizer PD features an ability to reduce cycle slipping during acquisition. The Cycle Slip Preven-
tion (CSP) feature increases the PD gain during large phase errors. The specic phase error that triggers
the momentary increase in PD gain is set via Reg 0Bh[8:7]
1.11.7 Charge Pump Gain
A simplied diagram of the charge pump is shown in Figure 43. Charge pump Up and Down gains are set
by CP DN Gain and CP UP Gain respectively (Reg 09h[6:0] and Reg 09h [13:7]). The current gain of the
pump in Amps/radian is equal to the gain setting of this register divided by 2π.
For example if both CP DN Gain and CP UP Gain are set to ‘50d’ the output current of each pump will be 1
mA and the phase frequency detector gain kp = 1 mA/2π radians, or 159 µA/rad. See section 1.4 for more
information.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
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1.11.8 Charge Pump Phase Offset - Fractional Mode
In integer mode, the phase detector operates with zero offset. The divided reference signal and the divided
VCO signal arrive at the phase detector inputs at the same time. In fractional mode of operation, charge
pump linearity and ultimately, phase noise, is much better if the VCO and reference inputs are operated
with a phase offset. A phase offset is implemented by adding a constant DC offset current at the output of
the charge pump.
DC offset may be added to the UP or DN switching pumps using Reg 09h[21] or Reg 09h[22]. The
magnitude of the offset is controlled by Reg 09h[20:14], and can range from 0 to 635 µA in steps of 5 µA.
Down offset is highly recommended in fractional mode of operation. Integer mode of operation works best
with zero offset.
As an example, a PD comparison of fPD = 50 MHz (20 ns period) with the main pump gain set at 2 mA, and
a down (DN) offset of -385 µA would represent a phase offset of about (-385/2000)*360 = -69 degrees.
This is equivalent to the divided VCO arriving 3.8 ns after the reference at the PD input. It is critical that
phase offset be used in fractional mode. Normally, down offsets larger than 3 ns are typical.
If the charge pump gain is changed, for example to compensate for changes in VCO sensitivity, it is
recommended to change the charge pump offset proportionally to maintain a constant phase offset.
Figure 43. Charge Pump Gain & Offset Control
1.12 Frequency Tuning
HMC834LP6GE VCO subsystem always operates in fundamental frequency of operation (2800 MHz
to 4200 MHz). The HMC834LP6GE generates frequencies below its fundamental frequency (45 MHz
to 2800 MHz) by tuning to the appropriate fundamental frequency and selecting the appropriate Output
Divider setting (divide by 2/4/6.../60/62) in VCO_Reg 02h[5:0]. Conversely the HMC834LP6GE generates
frequencies greater than its fundamental frequency (5600 MHz to 8400 MHz) by tuning to the appropriate
fundamental frequency and enabling the doubler mode (VCO_Reg 03h[0] = 1).
The HMC834LP6GE automatically controls frequency tuning in the fundamental band of operation, for
more information see “1.2.1 VCO Auto-Calibration (AutoCal)”.
To tune to frequencies below the fundamental frequency range (<2800 MHz) it is required to tune the
HMC834LP6GE to the appropriate fundamental frequency, then select the appropriate output divider setting
(divide by 2/4/6.../60/62) in VCO_Reg 02h[5:0]. Similarly, to tune to frequencies above the fundamental
frequency range (>4200 MHz) it is required to tune the HMC834LP6GE to the appropriate fundamental
frequency, and then enable the doubler mode of operation (VCO_Reg 03h[0] = 1).
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
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1.12.1 Integer Mode
The HMC834LP6GE is capable of operating in integer mode. For Integer mode set the following registers
a. Disable the Fractional Modulator, Reg 06h[11]= 0
b. Bypass the Modulator circuit, Reg 06h[7]=1
In integer mode the VCO step size is xed to that of the PD frequency, fpd. Integer mode typically has 3
dB lower phase noise than fractional mode for a given PD operating frequency. Integer mode, however,
often requires a lower PD frequency to meet step size requirements. The fractional mode advantage is that
higher PD frequencies can be used, hence lower phase noise can often be realized in fractional mode.
Charge Pump offset should be disabled in integer mode.
1.12.1.1 Integer Frequency Tuning
In integer mode the digital ∆∑ modulator is shut off and the N (Reg 03h) divider may be programmed to any
integer value in the range 16 to 219-1. To run in integer mode congure Reg 06h as described, then program
the integer portion of the frequency as explained by (EQ 13), ignoring the fractional part.
a. Disable the Fractional Modulator, Reg 06h[11] = 0
b. Bypass the delta-sigma modulator Reg 06h[7] = 1
c. To tune to frequencies (<2800 MHz), select the appropriate output divider value VCO_Reg 02h[5:0].
d. To tune to frequencies (>4200 MHz), enable the doubler mode of operation (VCO_Reg 03h [0] = 1).
Writing to VCO subsystem registers (VCO_Reg 02h[5:0] and VCO_Reg 03h [0] in this case) is accomplished
indirectly through PLL register 5 (Reg 05h). More information on communicating with the VCO subsystem
through PLL Reg 05h is available in “1.19 VCO Serial Port Interface (SPI)” section.
1.12.2 Fractional Mode
The HMC834LP6GE is placed in fractional mode by setting the following registers:
a. Enable the Fractional Modulator, Reg 06h[11]=1
b. Connect the delta sigma modulator in circuit, Reg 06h[7]=0
1.12.2.1 Fractional Frequency Tuning
This is a generic example, with the goal of explaining how to program the output frequency. Actual variables
are dependant upon the reference in use.
The HMC834LP6GE in fractional mode can achieve frequencies at fractional multiples of the reference.
The frequency of the HMC834LP6GE, fvco, is given by
fvco = (Nint + Nfrac) = fint + ffrac
fxtal
R (EQ 13)
fout = fvco/ k (EQ 14)
Where:
fout is the output frequency after any potential dividers or doublers.
k is 0.5 for doubler, 1 for fundamental, or k = 1,2,4,6,…58,60,62 according to the
VCO Subsystem type
Nint is the integer division ratio, Reg 03h, an integer number between 20 and
524,284
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
34
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Nfrac is the fractional part, from 0.0 to 0.99999...,Nfrac=Reg 04h/224
R is the reference path division ratio, Reg 02h
fxtal is the frequency of the reference oscillator input
fpd is the PD operating frequency, fxtal/R
As an example:
fout 1402.5 MHz
k 2
fvco 2,805 MHz
fxtal = 50 MHz
R = 1
fpd = 50 MHz
Nint = 56
Nfrac = 0.1
Reg 04h = round(0.1 x 224) = round(1677721.6) = 1677722
fVCO = (56 + - ) = 2805 MHz + 1.92 Hz error
1677722
224
50e6
1(EQ 15)
fout = = 1402.5 MHz + 0.596 Hz error
fVCO
2(EQ 16)
In this example the output frequency of 1402.5 MHz is achieved by programming the 19-bit binary value
of 56d = 38h into intg_reg in Reg 03h, and the 24-bit binary value of 1677722d = 19999Ah into frac_reg in
Reg 04h. The 0.596 Hz quantization error can be eliminated using the exact frequency mode if required. In
this example the output fundamental is divided by 2. Specic control of the output divider is required. See
section 3.0 and description for more details.
1.12.2.2 Exact Frequency Tuning
Due to quantization effects, the absolute frequency precision of a fractional PLL is normally limited by
the number of bits in the fractional modulator. For example, a 24 bit fractional modulator has frequency
resolution set by the phase detector (PD ) comparison rate divided by 224. The value 224 in the denominator
is sometimes referred to as the modulus. Hittite PLLs use a xed modulus which is a binary number. In
some types of fractional PLLs the modulus is variable, which allows exact frequency steps to be achieved
with decimal step sizes. Unfortunately small steps using small modulus values results in large spurious
outputs at multiples of the modulus period (channel step size). For this reason Hittite PLLs use a large
xed modulus. Normally, the step size is set by the size of the xed modulus. In the case of a 50 MHz PD
rate, a modulus of 224 would result in a 2.98 Hz step resolution, or 0.0596 ppm. In some applications it is
necessary to have exact frequency steps, and even an error of 3 Hz cannot be tol erated.
Fractional PLLs are able to generate exact frequencies (with zero frequency error) if N can be
exactly represented in binary (eg. N = 50.0,50.5,50.25,50.75 etc.). Unfortunately, some common
frequencies cannot be exactly represented. For example, Nfrac = 0.1 = 1/10 must be approximated as
round((0.1 x 224)/ 224 ) ≈ 0.100000024. At fPD = 50 MHz this translates to 1.2 Hz error. Hittite’s exact frequency
mode addresses this issue, and can eliminate quantization error by programming the channel step size to
FPD/10 in Reg 0Ch to 10 (in this example). More generally, this feature can be used whenever the desired
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
35
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
frequency, fVCO, can be exactly represented on a step plan where there are an integer number of steps
(<214) across integer-N boundaries. Mathematically, this situation is satised if:
gcd gcd gcd
114
mod 0 where gcd( , ) 2
fPD
PD
VCOk VCO
f
f f f f and f 
 
 
 
= = ≥ (EQ 17)
Where:
gcd stands for Greatest Common Divisor
fN = maximum integer boundary frequency < fVCO1
fPD = frequency of the Phase Detector
and fVCOk are the channel step frequencies where 0 < k < 224-1, As shown in Figure 44.
Figure 44. Exact Frequency Tuning
Some fractional PLLs are able to achieve this by adjusting (shortening) the length of the Phase Accumulator
(the denominator or the modulus of the Delta-Sigma modulator) so that the Delta-Sigma modulator phase
accumulator repeats at an exact period related to the interval frequency (fVCOk - fVCO(k-1)) in Figure 44.
Consequently, the shortened accumulator results in more frequent repeating patterns and as a result often
leads to spurious emissions at multiples of the repeating pattern period, or at harmonic frequencies of
fVCOk - fVCO(k-1). For example, in some applications, these intervals might represent the spacing between
radio channels, and the spurious would occur at multiples of the channel spacing.
The Hittite method on the other hand is able to generate exact frequencies between adjacent integer-N
boundaries while still using the full 24 bit phase accumulator modulus, thus achieving exact frequency
steps with a high phase detector comparison rate, which allows Hittite PLLs to maintain excellent phase
noise and spurious performance in the Exact Frequency Mode.
1.12.2.3.3 Using Hittite Exact Frequency Mode
If the constraint in (EQ 17) is satised, HMC834LP6GE is able to generate signals with zero frequency error
at the desired VCO frequency. Exact Frequency Mode may be re-congured for each target frequency, or
be set-up for a xed fgcd which applies to all channels.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
36
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.12.2.4.4 Conguring Exact Frequency Mode For a Particular Frequency
1. Calculate and program the integer register setting Reg 03h = NINT = oor(fVCO/fPD), where the
oor function is the rounding down to the nearest integer. Then the integer boundary frequency
fN = NINT fPD
2. Calculate and program the exact frequency register value Reg 0Ch = fPD/fgcd, where
fgcd = gcd(fVCO,fPD)
3. Calculate and program the fractional register setting Reg 04h
( )
24
2
ceil N
VCO
FRAC PD
ff
Nf





−
= = , where ceil
is the ceiling function meaning “round up to the nearest integer.”
Example: To congure the HMC834LP6GE for exact frequency mode at fVCO = 2800.2 MHz where Phase
Detector (PD) rate fPD = 61.44 MHz Proceed as follows:
Check (EQ 17) to conrm that the exact frequency mode for this fVCO is possible.
()
gcd gcd 14
6
66 3
gcd 14
gcd( , ) 2
61.44 10
gcd 2800.2 10 ,61.44 10 120 10 3750
2
PD
PD
VCO
f
f f f and f
f




= ≥
×
= × × =×> =
Since (EQ 17) is satised, the HMC834LP6GE can be congured for exact frequency mode at
fVCO = 2800.2 MHz as follows:
1. NINT = Reg 03h = 6
6
2800.2 10 45 2
61.44 10
VCO
PD
f
floor floor d Dh
f

 

 
 
×
= = =
×
2. Reg 0Ch =
( )
()
66
66
61.44 10 61.44 10 512 200
120000
gcd , gcd 2800.2 10 ,61.44 10
PD
PD
VCO
fdh
ff
××
= = = =
××
3. To program Reg 04h, the closest integer-N boundary frequency fN that is less than the
desired VCO frequency fVCO must be calculated. fN = fPD  NINT. Using the current example:
( )
()
6
24 6 6
24
6
45 61.44 10 2764.8 .
2 2800.2 10 2764.8 10
2
Then Reg04h 9666560 938000
61.44 10
INT
N PD
N
VCO
PD
Nf f MHz
ff
ceil ceil d h
f





=× =× ×=
×− ×
−
= = = =
×
1.12.2.5.5 Hittite Exact Frequency Channel Mode
If it is desirable to have multiple, equally spaced, exact frequency channels that fall within
the same interval (ie. fN ≤ fVCOk < fN+1) where fVCOk is shown in Figure 44 and 1 ≤ k ≤ 214,
it is possible to maintain the same integer-N (Reg 03h) and exact frequency register (Reg 0Ch) settings
and only update the fractional register (Reg 04h) setting. The Exact Frequency Channel Mode is possible
if (EQ 17) is satised for at least two equally spaced adjacent frequency channels, i.e. the channel step
size.
To congure the HMC834LP6GE for Exact Frequency Channel Mode, initially and only at the beginning,
integer (Reg 03h) and exact frequency (Reg 0Ch) registers need to be programmed for the smallest fVCO
frequency (fVCO1 in Figure 44), as follows:
1. Calculate and program the integer register setting Reg 03h = NINT = oor(fVCO1/fPD), where fVCO1 is
shown in Figure 44 and corresponds to minimum channel VCO frequency. Then the lower integer
boundary frequency is given by fN = NINTfPD.
2. Calculate and program the exact frequency register value Reg 0Ch = fPD/fgcd,
where fgcd = gcd((fVCOk+1 - fVCOk),fPD) = greatest common divisor of the desired equidistant channel
spacing and the PD frequency ((fVCOk+1 - fVCOk) and fPD).
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
37
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Then, to switch between various equally spaced intervals (channels) only the fractional register (Reg 04h)
needs to be programmed to the desired VCO channel frequency fVCOk in the following manner:
Reg 04h =
( )
24
2
ceil N
VCOk
FRAC PD
ff
Nf





−
= where fN = oor(fVCO1/fPD), and fVCO1, as shown in Figure 44, represents
the smallest channel VCO frequency that is greater than fN.
Example: To congure the HMC834LP6GE for Exact Frequency Mode for equally spaced intervals of 100
kHz where rst channel (Channel 1) = fVCO1 = 2800.200 MHz and Phase Detector (PD) rate fPD = 61.44
MHz proceed as follows:
First check that the exact frequency mode for this fVCO1 = 2800.2 MHz (Channel 1)
and fVCO2 = 2800.2 MHz + 100 kHz = 2800.3 MHz (Channel 2) is possible.
()
()
gcd1 gcd1 gcd 2 gcd2
12
14 14
6
66 3
gcd1 14
6
6 63
gcd2 14
gcd( , ) gcd( , )
22
61.44 10
gcd 2800.2 10 ,61.44 10 120 10 3750
2
61.44 10
gcd 2800.3 10 ,61.44 10 20 10 3750
2
PD PD
PD PD
VCO VCO
ff
f f f and f and f f f and f
f
f
 
 
 
 
= ≥= ≥
×
= × × =×> =
×
= × × =×> =
If (EQ 17) is satised for at least two of the equally spaced interval (channel) frequencies fVCO1,fVCO2,fVCO3,...
fVCON, as it is above, Hittite Exact Frequency Channel Mode is possible for all desired channel frequencies,
and can be congured as follows:
1. Reg 03h =
6
1
6
2800.2 10
45 2
61.44 10
VCO
PD
f
floor floor d Dh
f




 
 
×
= = =
×
2. Reg 0Ch =
( )
(
)
()
66
36
1
61.44 10 61.44 10 3072 00
20000
gcd 100 10 ,61.44 10
gcd ,
PD
PD
VCOk VCOk
fdC h
f ff
+
××
= = = =
××
−
where (fVCOk+1 - fVCOk) is the desired channel spacing (100 kHz in this example).
3. To program Reg 04h the closest integer-N boundary frequency fN that is less than the smallest
channel VCO frequency fVCO1 must be calculated. fN = oor(fVCO1/fPD). Using the current example:
66
6
2800.2 10 45 61.44 10 2764.8
61.44 10
N PD
f f floor MHz




×
=× =× ×=
× Then
Reg 04h
( )
()
24 1
1
24 6 6
6
2 for channel 1 where 2800.2
2 2800.2 10 2764.8 10
9666560 938000
61.44 10
N
VCO
VCO
PD
ff
ceil f MHz
f
ceil d h











−
= =
×− ×
= = =
×
4. To change from channel 1 (fVCO1 = 2800.2 MHz) to channel 2 (fVCO2 = 2800.3 MHz), only
Reg 04h needs to be programmed, as long as all of the desired exact frequencies fVCOk (Figure 44)
fall between the same integer-N boundaries (fN < fVCOk < fN+1). In that case
Reg 04h =
()
24 6 6
6
2 2800.3 10 2764.8 10
9693867 93
61.44 10
ceil d EAABh






×− × = =
×, and so on.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
38
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.12.2.6 Seed Register & AutoSeed Mode
The start phase of the fractional modulator digital phase accumulator (DPA) may be set to one of four possible
default values via the seed register Reg 06h[1:0]. If AutoSeed Reg 06h[8] is set, then the HMC834LP6GE
will automatically reload the start phase into the DPA every time a new fractional frequency is selected.
If AutoSeed is not set, then the HMC834LP6GE will start new fractional frequencies with the last value
left in the DPA from the last frequency. Hence the start phase will effectively be random. Certain zero or
binary seed values may cause spurious energy correlation at specic frequencies. Correlated spurs are
advantageous only in very special cases where the spurious are known to be far out of band and are
removed in the loop lter. For most cases a random, or non zero, non-binary start seed is recommended.
Further, since the AutoSeed always starts the accumulators at the same place, performance is repeatable
if AutoSeed is used. Reg 06h[1:0]=2 is recommended.
1.13 Soft Reset & Power-On Reset
The HMC834LP6GE features a hardware Power on Reset (POR). All chip registers will be reset to default
states approximately 250 µs after power up.
The PLL subsystem SPI registers may also be soft reset by an SPI write to register rst_swrst (Reg 00h).
Note that the soft reset does not clear the SPI mode of operation referred to in section 1.17. 2 . It should be
noted that the VCO subsystem is not affected by the PLL soft reset, the VCO subsystem registers can only
be reset by removing the power supply.
NOTE: if external power supplies or regulators have rise times slower than 250 µs, then it is advised to
write to the SPI reset register (Reg 00h[5]=1) immediately after power up, before any other SPI activity.
This will ensure starting from a known state.
1.14 Power Down Mode
Note that the VCO subsystem is not affected by the CEN or soft reset. Hence device power down is a two
step process. First power down the VCO by writing 0 to VCO register 1 via Reg 05h and then power down
the PLL by pulling CEN pin 17 low (assuming no SPI overrides (Reg 01h[0]=1)). This will result in all analog
functions and internal clocks disabled. Current consumption will typically drop below 10 µA in Power Down
state. The serial port will still respond to normal communication in Power Down mode.
It is possible to ignore the CEN pin, by clearing rst_chipen_pin_select (Reg 01h[0]=0). Control of Power
Down Mode then comes from the serial port register rst_chipen_from_spi, Reg 01h[1] .
It is also possible to leave various blocks on when in Power Down (see Reg 01h), including:
a. Internal Bias Reference Sources Reg 01h[2]
b. PD Block Reg 01h[3]
c. CP Block Reg 01h[4]
d. Reference Path Buffer Reg 01h[5]
e. VCO Path buffer Reg 01h[6]
f. Digital I/O Test pads Reg 01h[7]
To turn off the VCO RF buffer but leave the VCO running and the PLL locked write Reg 05h = 2A98(manual
select) then write Reg 05h = 0D88(disable VCO RF buffer) To re-enable the RF buffer write Reg
05h=0F88(Enable VCO RF buffer)
1.15 Chip Identication
PLL subsystem version information may be read by reading the content of read only register, chip_ID in
Reg 00h. It is not possible to read the VCO subsystem version.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
39
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.16 General Purpose Output (GPO) Pin
The PLL shares the LD_SDO (Lock-Detect/Serial Data Out) pin to perform various functions. While the pin
is most commonly used to read back registers from chip via the SPI, it is also capable of exporting a variety
of interesting signals and real time test waveforms (including Lock Detect). It is driven by a tri-state CMOS
driver with ~200  Rout. It has logic associated with it to dynamically select whether the driver is enabled,
and to decide which data to export from the chip.
In its default conguration, after power-on-reset, the output driver is disabled, and only drives during
appropriately addressed SPI reads. This allows it to share the output with other devices on the same bus.
Depending on the SPI mode, the read section of SPI cycle is recognized differently
HMC SPI Mode: The driver is enabled during the last 24 bits of SPI READ cycle (not during write
cycles).
Open SPI Mode: The driver is enabled if the chip is addressed - ie. The last 3 bits of SPI cycle =
‘000’b before the rising edge of SEN (Note A).
To monitor any of the GPO signals, including Lock Detect, set Reg 0Fh[7] = 1 to keep the SDO driver
always on. This stops the LDO driver from tri-stating and means that the SDO line cannot be shared with
other devices.
The chip will naturally switch away from the GPO data and export the SDO during an SPI read (Note B). To
prevent this automatic data selection, and always select the GPO signal, set “Prevent AutoMux of SDO”
(Reg 0Fh[6] = 1). The phase noise performance at this output is poor and uncharacterized. Also, the GPO
output should not be toggling during normal operation. Otherwise the spectral performance may degrade.
Note that there are additional controls available, which may be helpful if sharing the bus with other devices:
• To allow the driver to be active (subject to the conditions above) even when the chip is disabled - set
Reg 01h[7] = 0.
• To disable the driver completely, set Reg 08h[5] = 0 (it takes precedence over all else).
• To disable either the pull-up or pull-down sections of the driver, Reg 0Fh[8] = 1 or Reg 0Fh[9] = 1
respectively.
Note A: If SEN rises before SCK has clocked in an ‘invalid’ (non-zero) chip -address, the HMC834LP6GE
will start to drive the bus.
Note B: In Open Mode, the active portion of the read is dened between the 1st SCK rising edge after
SEN, to the next rising edge of SEN.
Example Scenarios:
• Drive SDO during reads, tri-state otherwise (to allow bus-sharing)
• No action required.
• Drive SDO during reads, Lock Detect otherwise
• Set GPO Select Reg 0Fh[4:0] = ‘00001’ (which is default)
• Set “Prevent GPO driver disable” (Reg 0Fh[7] = 1)
• Always drive Lock Detect
• Set “ Prevent AutoMux of SDO” Reg 0Fh[6] = 1
• Set GPO Select Reg 0Fh[4:0]= 00001 (which is default)
• Set “Prevent GPO driver disable” (Reg 0Fh[7] = 1))
The signals available on the GPO are selected by changing “GPO Select”, Reg 0Fh[4:0].
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
40
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.17 SERIAL PORT
1.17.1 Serial Port Modes of Operation
The HMC834LP6GE serial port interface can operate in two different modes of operation.
a. HMCSPI HMC Mode (HMC Legacy Mode) - Single slave per HMCSPI Bus
b. HMCSPI Open Mode - Up to 8 slaves per HMCSPI Bus.
Both Modes support 5-bits of register address space. HMC Mode can support up to 6 bits of register
address.
Register 0 has a dedicated function in each mode. Open Mode allows wider compatibility with other
manufacturers SPI protocols.
Table 4. Register 0 Comparison - Single vs Multi-User Modes
Single User
HMC Mode
Multi-User
Open Mode
READ Chip ID
24-bits Chip ID 24-bits
WRITE Soft Reset,
General Strobes
Read Address [4:0]
Soft reset [5]
General Strobes [23:6]
1.17.2 HMCSPI Protocol Decision after Power-On Reset
On power up both types of modes are active and listening.
A decision to select the desired SPI protocol is made on the rst occurrence of SEN or SCLK following a
hard reset, after which the protocol is xed and only changeable by cycling the power OFF and ON.
a. If a rising edge on SEN is detected rst HMC Mode is selected.
b. If a rising edge on SCLK is detected rst Open mode is selected.
1.17.3 Serial Port HMC Mode - Single PLL
HMC Mode (Legacy Mode) serial port operation can only address and talk to a single PLL, and is compatible
with most Hittite PLLs and PLLs with Integrated VCOs.
The HMC Mode protocol, shown in gures Figure 45 and Figure 46, is designed for a 4 wire interface with
a xed protocol featuring
a. 1 Read/Write bit
b. 6 Address bits
c. 24 data bits
d. 3 wire for Write only, 4 wire for Read/Write capability
1.17.3.1 HMC Mode - Serial Port WRITE Operation
AVDD = DVDD = 3V ±10%, AGND = DGND = 0V
Table 5. SPI HMC Mode - Write Timing Characteristics
Parameter Conditions Min. Typ. Max Units
t1SEN to SCLK setup time 8 ns
t2SDI to SCLK setup time 3 ns
t3SCLK to SDI hold time 3 ns
t4SEN low duration 20 ns
t5SCK to SEN fall 10 ns
Max Serial port Clock Speed 50 MHz
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
41
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
A typical HMC Mode WRITE cycle is shown in Figure 45.
a. The Master (host) both asserts SEN (Serial Port Enable) and clears SDI to indicate a WRITE cycle,
followed by a rising edge of SCK.
b. The slave (synthesizer) reads SDI on the 1st rising edge of SCK after SEN. SDI low indi cates a Write
cycle (/WR).
c. Host places the six address bits on the next six falling edges of SCK, MSB rst.
d. Slave shifts the address bits in the next six rising edges of SCK (2-7).
e. Host places the 24 data bits on the next 24 falling edges of SCK, MSB rst.
f. Slave shifts the data bits on the next 24 rising edges of SCK (8-31).
g. The data is registered into the chip on the 32nd rising edge of SCK.
h. SEN is cleared after a minimum delay of t5. This completes the write cycle.
Figure 45. HMC Mode - Serial Port Timing Diagram - WRITE
1.17.3.2 HMC Mode - Serial Port READ Operation
A typical HMC Mode READ cycle is shown in Figure 46.
a. The Master (host) asserts both SEN (Serial Port Enable) and SDI to indicate a READ cycle, followed
by a rising edge SCLK. Note: The Lock Detect (LD) function is usually multiplexed onto the LD_SDO
pin. It is suggested that LD only be considered valid when SEN is low. In fact LD will not toggle until
the rst active data bit toggles on LD_SDO, and will be restored immediately after the trailing edge of
the LSB of serial data out as shown in Figure 46.
b. The slave (HMC834LP6GE) reads SDI on the 1st rising edge of SCLK after SEN. SDI high initiates
the READ cycle (RD)
c. Host places the six address bits on the next six falling edges of SCLK, MSB rst.
d. Slave registers the address bits on the next six rising edges of SCLK (2-7).
e. Slave switches from Lock Detect and places the requested 24 data bits on SD_LDO on the next 24
rising edges of SCK (8-31), MSB rst .
f. Host registers the data bits on the next 24 falling edges of SCK (8-31).
g. Slave restores Lock Detect on the 32nd rising edge of SCK.
h. De-assertion of SEN completes the cycle
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
42
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
Table 6. SPI HMC Mode - Read Timing Characteristics
Parameter Conditions Min. Typ. Max Units
t1SEN to SCLK setup time 8 ns
t2SDI to SCLK setup time 3 ns
t3SCLK to SDI hold time 3 ns
t4SEN low duration 20 ns
t5SCLK to SDO delay 8.2ns+0.2
ns/pF ns
t6Recovery Time 10 ns
Figure 46. HMC Mode - Serial Port Timing Diagram - READ
1.17.4 Serial Port Open Mode
The Serial Port Open Mode, shown in Figure 47 and Figure 48, features:
a. Compatibility with general serial port protocols that use shift and strobe approach to communication
b. Compatible with Hittite PLL with Integrated VCO solutions, useful to address multiple chips of various
types from a single serial port bus.
The Open Mode protocol has the following general features:
a. 3-bit chip address , can address up to 8 devices connected to the serial bus
b. Wide compatibility with multiple protocols from multiple vendors
c. Simultaneous Write/Read during the SPI cycle
d. 5-bit address space
e. 3 wire for Write Only capability, 4 wire for Read/Write capability
Hittite PLLs with integrated VCOs support Open Mode. Some legacy PLL and microwave PLLs with
integrated VCOs only support HMC Mode. Consult the relevant data sheets for details.
Typical serial port operation can be run with SCLK at speeds up to 50 MHz.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
43
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.17.4.1 Open Mode - Serial Port WRITE Operation
AVDD = DVDD = 3V ±10%, AGND = DGND = 0V
Table 7. SPI Open Mode - WRITE Timing Characteristics
Parameter Conditions Min. Typ. Max Units
t1SDI setup time to SCLK Rising Edge 3 ns
t2SCLK Rising Edge to SDI hold time 3 ns
t3SEN low duration 10 ns
t4SEN high duration 10 ns
t5SCLK 32 Rising Edge to SEN Rising Edge 10 ns
t6Recovery Time 20 ns
Max Serial port Clock Speed 50 MHz
A typical WRITE cycle is shown in Figure 47.
a. The Master (host) places 24-bit data, d23:d0, MSB rst, on SDI on the rst 24 falling edges of SCLK.
b. the slave (HMC834LP6GE) shifts in data on SDI on the rst 24 rising edges of SCLK
c. Master places 5-bit register address to be written to, r4:r0, MSB rst, on the next 5 falling edges of SCLK
(25-29)
d. Slave shifts the register bits on the next 5 rising edges of SCLK (25-29).
e. Master places 3-bit chip address, a2:a0, MSB rst, on the next 3 falling edges of SCLK (30-32). Hittite
reserves chip address a2:a0 = 000 for all RF PLL with Integrated VCOs.
f. Slave shifts the chip address bits on the next 3 rising edges of SCLK (30-32).
g. Master asserts SEN after the 32nd rising edge of SCLK.
h. Slave registers the SDI data on the rising edge of SEN.
Figure 47. Open Mode - Serial Port Timing Diagram - WRITE
1.17.4.2 Open Mode - Serial Port READ Operation
A typical READ cycle is shown in Figure 48.
In general, in Open Mode the LD_SDO line is always active during the WRITE cycle. During any Open
Mode SPI cycle LD_SDO will contain the data from the current address written in Reg0h[7:3]. If Reg0h[7:3]
is not changed then the same data will always be present on LD_SDO when an Open Mode cycle is in
progress. If it is desired to READ from a specic address, it is necessary in the rst SPI cycle to write the
desired address to Reg0h[7:3], then in the next SPI cycle the desired data will be available on LD_SDO.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
44
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
An example of the Open Mode two cycle procedure to read from any random address is as follows:
a. The Master (host), on the rst 24 falling edges of SCLK places 24-bit data, d23:d0, MSB rst, on SDI
as shown in Figure 48. d23:d5 should be set to zero. d4:d0 = address of the register to be READ on
the next cycle.
b. the slave (HMC834LP6GE) shifts in data on SDI on the rst 24 rising edges of SCLK
c. Master places 5-bit register address , r4:r0, (the READ ADDRESS register), MSB rst, on the next 5
falling edges of SCLK (25-29). r4:r0=00000.
d. Slave shifts the register bits on the next 5 rising edges of SCLK (25-29).
e. Master places 3-bit chip address, a2:a0, MSB rst, on the next 3 falling edges of SCLK (30-32)..Chip
address is always 000 for RF PLL with Integrated VCOs.
f. Slave shifts the chip address bits on the next 3 rising edges of SCLK (30-32).
g. Master asserts SEN after the 32nd rising edge of SCLK.
h. Slave registers the SDI data on the rising edge of SEN.
i. Master clears SEN to complete the the address transfer of the two part READ cycle.
j. If one does not wish to write data to the chip at the same time as we do the second cycle , then it is
recommended to simply rewrite the same contents on SDI to Register zero on the READ back part of
the cycle.
k. Master places the same SDI data as the previous cycle on the next 32 falling edges of SCLK.
l. Slave (HMC834LP6GE) shifts the SDI data on the next 32 rising edges of SCLK.
m. Slave places the desired read data (ie. data from the address specied in Reg 00h[7:3] of the rst
cycle) on LD_SDO which automatically switches to SDO mode from LD mode, disabling the LD
output.
m. Master asserts SEN after the 32nd rising edge of SCK to complete the cycle and revert back to Lock
Detect on LD_SDO.
Table 8. SPI Open Mode - Read Timing Characteristics
Parameter Conditions Min. Typ. Max Units
t1SDI setup time to SCLK Rising Edge 3 ns
t2SCLK Rising Edge to SDI hold time 3 ns
t3SEN low duration 10 ns
t4SEN high duration 10 ns
t5SCLK Rising Edge to SDO time 8.2ns+0.2ns/pF ns
t6Recovery TIme 10 ns
t7SCK 32 Rising Edge to SEN Rising Edge 10 ns
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
45
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.17.4.3 HMCSPI Open Mode READ Operation - 2 Cycles
Figure 48. Serial Port Timing Diagram - READ
For more information on using the GPO pin while in SPI Open Mode please see section 1.16.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
46
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.18 Conguration at Start-Up
To congure the PLL after power up, follow the instructions below:
1. Congure the reference divider (write to Reg 02h), if required.
2. Congure the delta-sigma modulator (write to Reg 06h).
• Conguration involves selecting the mode of the delta-sigma modulator (Mode A or Mode B),
selection of the delta-sigma modulator seed value, and conguration of the delta-sigma modulator
clock scheme. It is recommended to use the values found in the Hittite PLL evaluation board
control software register les.
3. Congure the charge pump current and charge pump offset current (write to Reg 09h)
4. Congure the VCO Subsystem (write to Reg 05h, for more information see section 1.19, and “3.0
VCO Subsystem Register Map”. Detailed writes to the VCO subsystem via PLL Reg 05h at start-up
are available in the Register Setting Files found in the HIttite PLL Evaluation Software received with a
product evaluation kit or downloaded from www.hittite.com.
5. Program the frequency of operation
• Program the integer part (write to Reg 03h)
• Program the fractional part (write to Reg 04h)
6. Congure the VCO output divider/doubler, if needed in the VCO subsystem via PLL Reg 05h.
Once the HMC834LP6GE is congured after startup, in most cases the user only needs to change
frequencies by writing to Reg 03h integer register, Reg 04h fractional register, and Reg 05h to change the
VCO output divider or doubler setting if needed, and possibly adjust the charge pump settings by writing
to Reg 09h.
For detailed and most up-to-date start-up conguration please refer to the appropriate Register Setting
Files found in the HIttite PLL Evaluation Software received with a product evaluation kit or downloaded
from www.hittite.com.
1.19 VCO Serial Port Interface (SPI)
The HMC834LP6GE communicates with the internal VCO subsystem via an internal 16 bit VCO Serial
Port, (e.g. see Figure 29). The internal serial port is used to control the step tuned VCO and other VCO
subsystem functions, such as RF output divider / doubler control and RF buffer enable.
Note that the internal VCO subsystem SPI (VSPI) runs at the rate of the AutoCal FSM clock, TFSM, (section
1.2.1) where the FSM clock frequency cannot be greater than 50 MHz. The VSPI clock rate is set by
Reg 0Ah[14:13].
Writes to the VCO’s control registers are handled indirectly, via writes to Reg 05h of the PLL. A write to PLL
Reg 05h causes the PLL subsystem to forward the packet, MSB rst, across its internal serial link to the
VCO subsystem, where it is interpreted.
The VCO serial port has the capability to communicate with multiple subsystems inside the IC. For this
reason each subsystem has a subsystem ID, Reg 05h[2:0].
Each subsystem has multiple registers to control the functions internal to the subsystem, which may be
different from one subsystem to the next. Hence each subsystem has internal register addresses bits
(Reg 05h[6:3])
Finally the data required to congure each register within the VCO subsystem is contained in Reg 05h[15:7].
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
47
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
1.19.1 VSPI Use of Reg05h
The packet data written into, Reg 05h is sub-parsed by logic at the VCO subsystem into the following 3
elds:
1. [2:0] - 3 bits - VCO_ID, target subsystem address = 000b.
2. [6:3] - 4 bits - VCO_REGADDR, the internal register address inside the VCO subsystem.
3. [15:7] - 9- bits- VCO_DATA, data eld to write into the VCO register.
For example, to write 0_1111_1110 into register 2 of the VCO subsystem (VCO_ID = ‘000’b), and set the
VCO output divider to divide by 62, the following needs to be written to Reg 05h =’0 _1111_1110, 0 010, 00 0 ’
b.
During AutoCal, the AutoCal controller only updates the data eld of Reg 05h. The VCO subsystem register
address (Reg 05h[6:3]) must be set to 0000 for the AutoCal data to be sent to the correct address.
VCO subsystem ID and register address are not modied by the AutoCal state machine. Hence, if a
manual access is done to a VCO Subsystem register the user must reset the register address to zero
before a change of frequency which will re-run AutoCal.
Since every write to Reg 05h will result in a transfer of data to the VCO subsystem, if the VCO
subsystem needs to be reset manually, it is important to make sure that the VCO switch settings are
not changed. Hence the switch settings in Reg 10h[7:0] need to be read rst, and then rewritten to
Reg 05h[15:8].
In summary, rst read Reg 10h, then write to Reg 05h as follows:
Reg 10h[7:0] = vv x yyyyy
Reg 05h = vv x yyyyy 0 0000 iii
Reg 05h[2:0] = iii, subsystem ID, 3 bits (000)
Reg 05h[6:3] = 0000, subsystem register address
Reg 05h[7] = 0 , calibration tune voltage off
Reg 05h[12:8] = yyyyy, VCO caps
Reg 05h[13] = x, don’t care
Reg 05h[15:14] = vv, VCO Select
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
48
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.0 PLL Register Map
2.1 Reg 00h ID Register (Read Only)
Bit Type Name Width Default Description
[23:0] RO chip_ID 24 A7975 HMC834LP6GE chip ID
2.2 Reg 00h Open Mode Read Address/RST Strobe Register (Write Only)
Bit Type Name Width Default Description
[4:0] WO Read Address 5 - (WRITE ONLY) Read Address for next cycle - Open Mode
Only
[5] WO Soft Reset 1 - Soft Reset - both SPI modes reset (set to 0 for proper
operation)
[23:6] WO Not Dened 18 - Not Dened (set to 0 for proper operation)
2.3 Reg 01h RST Register
(Default 000002h)
Bit Type Name Width Default Description
[0] R/W rst_chipen_pin_select 1 0
1 = take PLL enable via CEN pin, see Power Down Mode
description
0 = take PLL enable via SPI (rst_chipen_from_spi)
Reg01[1]
[1] R/W rst_chipen_from_spi 1 1 SPI’s PLL enable bit
[2] R/W Keep_bias_on 1 0 when PLL is disabled, keeps internal bias generators on,
ignores chip enable control.
[3] R/W Keep_PD_on 1 0 when PLL is disabled, keeps PD circuit on, ignores Chip
enable control
[4] R/W Kee p_CP_ on 1 0 when PLL is disabled, keeps Charge Pump on, ignores
Chip enable control
[5] R/W Keep_Ref_buf_on 1 0 when PLL is disabled, keeps Reference buffer block on,
ignores Chip enable control
[6] R/W Keep_VCO_on 1 0 when PLL is disabled, keeps VCO divider buffer on,
ignores Chip enable control
[7] R/W Keep_GPO_driver_on 1 0 when PLL is disabled, keeps GPO output Driver On,
ignores Chip enable control
[8] R/W Reserved 1 0 Reserved
[9] R/W Reserved 1 0 Reserved
2.4 Reg 02h REFDIV Register
(Default 000001h)
Bit Type Name Width Default Description
[13:0] R/W rdiv 14 1
Reference Divider ’R’ Value “(EQ 13)”)
Divider use also requires refBufEn Reg08[3]=1and Divider
min 1d
max 16383d
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
49
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.5 Reg 03h Frequency Register - Integer Part
(Default 000019h)
Bit Type Name Width Default Description
[18:0] R/W intg 19 25d
VCO Divider Integer part, used in all modes, see (EQ 13)
Fractional Mode
min 20d
max 219 -4 = 7FFFCh = 524,284d
Integer Mode
min 16d
max 219-1 = 7FFFFh = 524,287d
2.6 Reg 04h Frequency Register - Fractional Part
(Default 000000h)
Bit Type Name Width Default Description
[23:0] R/W frac 24 0
VCO Divider Fractional part (24-bit unsigned) see
Fractional Frequency Tuning
Used in Fractional Mode only (Nfrac= Reg 04h/224
min 0d
max 224-1
2.7 Reg 05h VCO SPI Register
(Default 000000h)
Bit Type Name Width Default Description
[2:0] R/W VCO Subsystem_ID, 3 0 Internal VCO Subsystem ID
[6:3] R/W VCO Subsystem register address 4 0 For interfacing with the VCO please see section 1.19.
[15:7] R/W VCO Subsystem data 9 0
Note: Reg05h is a special register used for indirect addressing of the VCO subsystem. Writes to Reg05h are
automatically forwarded to the VCO subsystem by the VCO SPI state machine controller.
Reg05h is a Read-Write register. However, Reg05h only holds the contents of the last transfer to the VCO subsystem.
Hence it is not possible to read the full contents of the VCO subsystem. Only the content of the last transfer to the
VCO subsystem can be read. Please take note special considerations for AutoCal related to Reg05h
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
50
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.8 Reg 06h SD CFG Register
(Default 200B4Ah)
Bit Type Name Width Default Description
[1:0] R/W seed 2 2
Selects the Seed in Fractional Mode
00: 0 seed
01: lsb seed
02: B29D08h seed
03: 50F1CDh seed
Note; Writes to this register are stored in the
HMC834LP6GE and are only loaded into the modulator
when a frequency change is executed and if AutoSeed
Reg06h[8] =1
[3:2] R/W order 2 2
Select the Modulator Type
0: 1st order
1: 2nd order
2: Type 1 Mode B
3: Type 2 Mode A
[6:4] R/W Reserved 3 4 Program to 7d
[7] R/W frac_bypass 1 0
0: Use Modulator, Required for Fractional Mode,
1: Bypass Modulator, Required for Integer Mode
Note: In bypass fractional modulator output is ignored,
but fractional modulator continues to be clocked if frac_
rstb =1, Can be used to test the isolation of the digital
fractional modulator from the VCO output in integer mode
[8] R/W AutoSeed 1 1
1: loads the seed whenever the frac register is written
0: when frac register write changes frequency, modulator
starts with previous contents
[9] R/W clkrq_refdiv_sel 1 1
selects the modulator clock source- for Test Only
1: VCO divider clock (Recommended for normal
operation)
0: Ref divider clock
Ignored if bits [10] or [21] are set
[10] R/W SD Modulator Clk Select 1 0 0 - SD auxclk,
1- SD VCO Clock delay (Recommended)
[11] R/W SD Enable 1 1
0: disable frac core, use for Integer Mode or Integer Mode
with CSP
1: Enable Frac Core, required for Fractional Mode, or
Integer isolation testing
This register controls whether AutoCal starts on an
Integer or a Fractional write
[12] R/W Reserved 1 0
[13] R/W Reserved 1 0
[15:14] R/W Reserved 2 0
[17:16] R/W Reserved 2 0 Program to 3d
[18] R/W BIST Enable 1 0 Enable Built in Self Test
[20:19] R/W RDiv BIST Cycles 2 0
RDiv BIST Cycles
00: 1032
01: 2047
10: 3071
11: 4095
[21] R/W auto_clock_cong 1 1 Set to 0 for fpd > 50 MHz
[22] R/W Reserved 1 0
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
51
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.9 Reg 07h Lock Detect Register
(Default 00014Dh)
Bit Type Name Width Default Description
[2:0] R/W lkd_wincnt_max 35d
lock detect window
sets the number of consecutive counts of divided VCO
that must land inside the Lock Detect Window to declare
LOCK
0: 5
1: 32
2: 96
3: 256
4: 512
5: 2048
6: 8192
7: 65535
[3] R/W Enable Internal Lock Detect 1 1 see section 1.16
[5:4] R/W Reserved 2 0 Reserved
[6] R/W Lock Detect Window type 1 1
Lock Detection Window Timer Selection
1: Digital programmable timer
0: Analog one shot, nominal 10 ns window
[9:7] R/W LD Digital Window duration 3 2
0 Lock Detection - Digital Window Duration
0: 1/2 cycle
1: 1 cycle
2: 2 cycles
3: 4 cycles
4: 8 cycles
5: 16 cycles
6: 32 cycles
7: 64 cycles
[11:10] R/W LD Digital Timer Freq Control 2 0 Lock Detect Digital Timer Frequency Control
“00” fastest “11” slowest
[12] R/W LD Timer Test Mode 1 0 1: force Timer Clock ON Continuously - For Test Only
0: Normal Timer operation - one shot
[13] R/W Auto Relock - One Try 1 0 1: Attempts to relock if Lock Detect fails for any reason
Only tries once.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
52
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.10 Reg 08h Analog EN Register
(Default C1BEFFh)
Bit Type Name Width Default Description
[0] R/W bias_en 1 1 Enables main chip bias reference
[1] R/W cp_en 1 1 charge pump enable
[2] R/W PD_en 1 1 PD enable
[3] R/W refbuf_en 1 Reference path buffer enable
[4] R/W vcobuf_en 1 1 VCO path RF buffer enable
[5] R/W gpo_pad_en 1 1
0 - Pin LD_SDO disabled
1 - and RegFh[7]=1 , Pin LD_SDO is always on required
for use of GPO port
1 - and RegFh[7]=0 SPI LDO_SPI is off if unmatched chip
address is seen on the SPI, allowing a shared SPI with
other compatible parts
[6] R/W reserved 1 1 reserved
[7] R/W VCO_Div_Clk_to_dig_en 1 1 VCO Divider Clock to Digital Enable
[8] R/W reserved 1 0 reserved
[9] R/W Prescaler Clock enable 1 1 Prescaler clock enable
[10] R/W VCO Buffer and Prescaler
Bias Enable 1 1 VCO Buffer and Prescaler Bias Enable
[11] R/W Charge Pump Internal
Opamp enable 1 1 Should be programmed to 1
[14:12] R/W reserved 3 011 reserved
[17:15] R/W reserved 3 011 reserved
[18] R/W spare 1 0 spare
[19] R/W reserved 1 0 reserved
[20] R/W reserved 1 0 reserved program to 0
[21] R/W High Frequency Reference 1 0 Program to 1 for XTAL > 200 MHz
[22] R/W reserved 1 1 reserved program to 1
[23] R/W reserved 1 1 reserved program to 1
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
53
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.11 Reg 09h Charge Pump Register
(Default 403264h)
Bit Type Name Width Default Description
[6:0] R/W CP DN Gain 7 100d
64h
Charge Pump DN Gain Control 20 µA√step
Affects fractional phase noise and lock detect settings
0d = 0 µA
1d = 20 µA
2d = 40 µA
...
127d = 2.54mA
[13:7] R/W CP UP Gain 7 100d
64h
Charge Pump UP Gain Control 20 µA per step
Affects fractional phase noise and lock detect settings
0d = 0 µA
1d = 20 µA
2d = 40 µA
...
127d = 2.54mA
[20:14] R/W Offset Magnitude 7 0
Charge Pump Offset Control 5 µA/step
Affects fractional phase noise and lock detect settings
0d = 0 µA
1d = 5 µA
2d = 10 µA
...
127d = 635 µA
[21] R/W Offset UP enable 1 0 recommended setting = 0
[22] R/W Offset DN enable 1 1 recommended setting = 1 in Fractional Mode, 0 otherwise
[23] R/W HiKcp 1 0 HiKcp High Current Charge Pump
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
54
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.12 Reg 0Ah VCO AutoCal Conguration Register
(Default 002205h)
Bit Type Name Width Default Description
[2:0] R/W Vtune Resolution 3 5
R Divider Cycles
0 - 1
1 - 2
2 - 4
3 - 8
4 - 32
5 - 64
6 - 128
7 - 256
[5:3] R/W VCO Curve Adjustment 3 0
VCO Curve Adjustment vs Temp for AutoCal
0 - Disabled
1 : + 1 Curve
2: +2 Curves
3: +3 Curves
4: -4 Curves
5: -3 Curves
6: -2 Curves
7: -1 Curve
[7:6] R/W Wait State Set Up 2 0
Wait State Setup 100 TFSM see section 1.2.4
Tmmt = 1 measurement cycle of AutoCal
0: Wait Only at Startup
1: Wait on startup and after rst Tmmt cycle
2: Wait on startup and after rst two Tmmt cycles
3: Wait on startup and after rst three Tmmt cycles
[9:8] R/W Num of SAR BIts in VCO 2 0
Number of SAR bits in VCO
0: 8 - recommended
1: 7
2: 6
3: 5
[10] R/W Force Curve 1 0 Force curve sent during Tuning Tune from Reg5
[11] R/W Bypass VCO Tuning 1 0 Bypass VCO Tuning
[12] R/W No VSPI Trigger 1 0 Don’t trigger a transfer on writes to Reg 05h
[14:13] R/W FSM/VSPI Clock Select 2 1
Set the AutoCal FSM and VSPI Clock (50 MHz maximum)
0: Input Crystal Reference
1: Input Crystal Reference/4
2: Input Crystal Reference/16
3: Input Crystal Reference/32
[15] R/W Xtal Falling Edge for FSM 1 0 Use the falling Edge of the Xtal for FSM AutoCal Clock -
Required for BIST
[16] R/W Force RDivider Bypass 1 0 Force the R Divider Bypass
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
55
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.13 Reg 0Bh PD Register
(Default 7C061h)
Bit Type Name Width Default Description
[2:0] R/W PD_del_sel 3 1 Sets PD reset path delay (Recommended setting 001)
[3] R/W Short PD Inputs 1 0 Shorts the inputs ot the Phase frequency detector - Test
Only
[4] R/W pd_phase_sel 1 0
Inverts the PD polarity (program to 0)
0- Use with a positive tuning slope VCO and Passive
Loop Filter (default)
1- Use with a Negative Slope VCO or with an inverting
Active Loop Filter with a Positive Slope VCO
[5] R/W PD_up_en 1 1 Enables the PD UP output
[6] R/W PD_dn_en 1 1 Enables the PD DN output
[8:7] R/W CSP Mode 2 0
Cycle Slip Prevention Mode
Extra current is driven into the loop lter when the phase
error is larger than:
0: Disabled
1: 5.4ns
2: 14.4ns
3: 24.1ns
This delay varies by +- 10% with temperature, and +- 12%
with process.
[9] R/W Force CP UP 1 0 Forces CP UP output on - Use for Test only
[10] R/W Force CP DN 1 0 Forces CP DN output on - Use for Test only
[11] R/W Force CP MId Rail 1 0 Force CP MId Rail - Use for Test only
[14:12] R/W Reserved 3 4 program to 100
[16:15] R/W CP Internal OpAmp Bias 2 3 program to 11
[18:17] R/W MCounter Clock Gating 2 3
MCounter Clock Gating
0: MCounter Off
1: N<128
2: N< 1023
3: All Clocks ON
(Recommended setting 11)
[19] R/W reserved 1 0 program to 0
[21:20] R/W reserved 2 0 program to 00
[23:22] R/W reserved 2 0 program to 00
2.14 Reg 0Ch Exact Frequency Mode Register
(Default 000000h)
Bit Type Name Width Default Description
[13:0] R/W Number of Channels per Fpd 14 0
Comparison Frequency divided by the Correction Rate,
Must be an integer. Frequencies at exactly the correction
rate will have zero frequency error.
0: Disabled
1: Disabled
2:16383d (3FFFh)
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
56
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.15 Reg 0Fh GPO_SPI_RDIV Register
(Default 000001h)
Bit Type Name Width Default Description
[4:0] R/W gpo_select 51d
Signal selected here is output to SDO pin when enabled
0: Data from Reg0F[5]
1: Lock Detect Output
2. Lock Detect Trigger
3: Lock Detect Window Output
4: Ring Osc Test
5. Pullup Hard from CSP
6. PullDN hard from CSP
7. Reserved
8: Reference Buffer Output
9: Ref Divider Output
10: VCO divider Output
11. Modulator Clock from VCO divider
12. Auxiliary Clock
13. Aux SPI Clock
14. Aux SPI Enable
15. Aux SPI Data Out
16. PD DN
17. PD UP
18. SD3 Clock Delay
19. SD3 Core Clock
20. AutoStrobe Integer Write
21. Autostrobe Frac Write
22. Autostrobe Aux SPI
23. SPI Latch Enable
24. VCO Divider Sync Reset
25. Seed Load Strobe
26.-29 Not Used
30. SPI Output Buffer En
31. Soft RSTB
[5] R/W GPO Test Data 1 0 1 - GPO Test Data
[6] R/W Prevent Automux SDO 1 0 1- Outputs GPO data only
0 - Automuxes between SDO and GPO data
[7] R/W LDO Driver Always On 1 0 1- LD_SDO Pin Driver always on
0 - LD_SDO Pin driver only on during SPI read cycle
[8] R/W Disable PFET 1 0 program to 0
[9] R/W Disable NFET 1 0 program to 0
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
57
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
2.16 Reg 10h VCO Tune Register
(Default 000020h)
Bit Type Name Width Default Description
[7:0] RO VCO Switch Setting 832
Read Only Register. Indicates the VCO switch setting
selected by the AutoCal state machine to yield the
nearest free running VCO frequency to the desired
operating frequency. Not valid when Reg10h[8] = 1,
AutoCal Busy. Note if a manual change is done to the
VCO switch settings this register will not indicate the
current VCO switch position.
0 = highest frequency
1 = 2nd highest
...
256 = lowest frequency
Note: VCO subsystems may not use all the MSBs, in
which case the unused bits are don’t care
[8] RO AutoCal Busy 1 0 Busy when AutoCal state machine is searching for the
nearest switch setting to the requested frequency.
2.17 Reg 11h SAR Register
(Default 007FFFh)
Bit Type Name Width Default Description
[18:0] RO SAR Error Mag Counts 19 219-1 SAR Error Magnitude Counts
[19] RO SAR Error Sign 1 0 SAR Error Sign 0=+ve 1=-ve
2.18 Reg 12h GPO2 Register
(Default 000000h)
Bit Type Name Width Default Description
[0] RO GPO 1 0 GPO State
[1] RO Lock Detect 1 0
Lock Detect Status
1 = Locked
0 = Unlocked
2.19 Reg 13h BIST Register
(Default 000000h)
Bit Type Name Width Default Description
[15:0] RO BIST Signature 19 4697d BIST Signature
[16] RO BIST Busy 1 0 BIST Busy
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
58
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
3.0 VCO Subsystem Register Map
Please note that the VCO subsystem uses indirect addressing via Reg 05h. For more detailed information
on how to write to the VCO subsystem please see section “1.19 VCO Serial Port Interface (SPI)”.
3.1 VCO_Reg 00h Tuning
Bit Type Name Width Default Description
[0] WO Cal 1 0 VCO tune voltage is redirected to a temperature
compensated calibration voltage
[8:1] WO CAPS 816
VCO sub-band selection.
0 - max frequency
1111 1111 - m in freq uen cy.
Not all sub-bands are used on the various products.
3.2 VCO_Reg 01h Enables
Bit Type Name Width Default Description
[0] WO Master Enable VCO Subsystem 1 1
0 - All VCO subsystem blocks Off
Manual mode (VCO_Reg 03h[2] = 1)
1- ANDed with local enables only
Auto Mode (VCO_Reg 03h[2] = 0)
1- Master enable ignores local enables
[1] WO Manual Mode PLL buffer enable 1 1 Enables PLL Buffer in manual mode only
[2] WO Manual Mode RF buffer enable 1 1 Enables RF Buffer to Output in manual mode only
[3] WO Manual Mode Divide by 1 enable 1 1 Enables RF divide by 1 in manual mode only
[4] WO Manual Mode RF Divider enable 1 1 Enables RF divider in manual mode only
[8:5] WO don’t care 4 0 don’t care
For example, to turn disable the RF buffer in the VCO subsystem and mute the output of the HMC834LP6GE, bit 2
in VCO_Reg01h needs to be cleared. If the other bits are left unchanged, then ‘0 0001 1011’ needs to be written into
VCO Reg01h. The VCO subsystem register is accessed via a write to PLL subsystem Reg 05h = ‘0 0001 1011 0001
000’ = D88h
Reg 05h[2:0] = 000; VCO subsystem ID 0
Reg 05h[6:3] = 0001; VCO subsystem register address
Reg 05h[7] = 1; Master enable
Reg 05h[8] = 1; PLL buffer enable
Reg 05h[9] = 0; Disable RF buffer
Reg 05h[10] = 1; Divide by 1 enable
Reg 05h[11] = 1; RF Divider enable
Reg 05h[16:12] = 0; don’t care
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
59
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
3.3 VCO_Reg 02h Biases
Bit Type Name Width Default Description
[5:0] WO RF Divide ratio 6 1
0 - Mute, VCO and PLL buffer On, RF output stages Off
1 - Fo
2 - Fo/2
3 - invalid, defaults to 2
4 - Fo/4
5 - invalid, defaults to 4
6 - Fo/6
...
60 - Fo/60
61 - invalid, defaults to 60
62 - Fo/62
> 62 - invalid, defaults to 62
Note: This register automatically controls the enables to
the, RF output buffer, RF divider, RF divide by 1 path,
and requires Master Enable (VCO_Reg 01h[0] = 1) and
AutoRFO mode (VCO_Reg 03h [2] = 0)
Note: bit[0] is a don’t care in ManualRFO mode.
[7:6] WO RF output buffer gain control 2 3
11 - Max Gain
10 - Max Gain - 3 dB
01 - Max Gain - 6 dB
00 - Max Gain - 9 dB
[8] WO Divider output stage gain control 1 0
1 - Max Gain
0 - Max Gain - 3 dB
Used to atten the output power level across frequency
•For divide-by 1 or divide-by 2 it is recommended to set
this bit to 1. 0 will reduce output power and degrade
noise oor performance.
•For divide-by 4 or higher, it is recommended to set this
bit to 0 to maintain at output power across divider
settings. Setting this bit to 1, with divide-by 4 or higher
provides higher output power compared to the divide-
by 1 or two case.
For example, to write 0_1111_1110 into VCO_Reg02h VCO subsystem (VCO_ID = ‘000’b), and set the VCO output
divider to divide by 62, the following needs to be written to Reg 05h =’0 _1111_1110, 0 010, 00 0’ b.
Reg 05h[2:0] = 00; subsystem ID 0
Reg 05h[6:3] = 0010; VCO register address 2d
Reg 05h[16:7] = 0_1111_1110; Divide by 62, max output RF gain, Divider output stage gain = 0
3.4 VCO_Reg 03h Cong
Bit Type Name Width Default Description
[0] WO Fundamental/Doubler Mode
Selection 1 1
0- Enable the frequency doubler mode of operation
1- Enable fundamental mode of operation
- For more information please see “VCO Subsystem”
section.
[1] WO reserved 1 0 reserved
[2] WO Manual RFO Mode 1 0
0 - AutoRFO mode (recommended)
1 - ManualRFO mode
AutoRFO mode controls output buffers and RF divider
enables according to RF divider setting in VCO_Reg
02h[5:0]
ManualRFO mode requires manual enables of individual
blocks via VCO_Reg01h
[4:3] WO RF buffer bias 2 2 Program to ‘10’ when fundamental mode enabled
Program to ‘00’ when doubler mode enabled
[8:5] WO Spare 4 2 don’t care
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
60
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
3.5 VCO_Reg 04h Cal/Bias
Specied performance is only guaranteed with the required settings in this table. Other settings are not
supported.
Bit Type Name Width Default Description
[2:0] WO VCO bias 3 1 Program to 5d
[4:3] WO PLL buffer bias 2 1 Program to 1d
[6:5] WO FndLmtr bias 2 2 Program to 3d
[8:7] WO Preset Cal 0 2 1 Program to 2d
3.6 VCO_Reg05h CF_Cal
Bit Type Name Width Default Description
[1:0] WO CF L 2 2 Program to 0d
[3:2] WO CF ML 2 2 Program to 3d
[5:4] WO CF MH 2 2 Program to 3d
[7:6] WO CF H 2 2 Program to 3d
[8] WO Spare 1 0 Program to 0d
3.7 VCO_Reg06h MSB Cal
Bit Type Name Width Default Description
[1:0] WO MSB L 2 3 Program to 3d
[3:2] WO MSB ML 2 3 Program to 3d
[5:4] WO MSB MH 2 3 Program to 3d
[7:6] WO MSB H 2 3 Program to 3d
[8] WO Spare 1 0 don’t care
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
PLLS WITH INTEGRATED VCO - SMT
61
HMC834LP6GE
v01.0112
FRACTIONAL-N PLL WITH INTEGRATED VCO
45 - 1050, 1400 - 2100, 2800 - 4200, 5600 - 8400 MHz
NOTES:
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
For price, delivery, and to place orders: Analog Devices, Inc.,
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
Phone: 781-329-4700 • Order online at www.analog.com
Application Support: Phone: 1-800-ANALOG-D