1
dc2091afa
DEMO MANUAL DC2091A
Description
LTC5599
30MHz to 1300MHz Low Power
Direct Quadrature Modulator
Demonstration circuit 2091A is optimized for evaluation
of the LT C
®
5599 low power direct quadrature modulator.
The balanced I and Q baseband input ports can be either
AC- or DC-coupled to a source with a common mode volt-
age level of about 1.4V. Fixed LC networks on the LO and
RF ports cover a continuous 90MHz to 1300MHz range.
The SPI interface controls the supply current, modulator
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
QuikEval is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners.
gain, and allows optimization of the LO carrier feedthrough
and side-band suppression.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2091A
MeasureMent setup
Figure 1. Test Setup for RF Performance Measurements
I+
I–
Q+
Q–
DC2091 F01
BB SIGNAL SOURCE
(VCMBB = 1.4VDC)
SPECTRUM
ANALYZER
LO SIGNAL
SOURCE
DC POWER SUPPLY
(3.3V)
– +
–3dB –6dB
2
dc2091afa
DEMO MANUAL DC2091A
notes on test equipMent anD setup
• Use high performance signal generators with fully
configurable differential I and Q outputs, such as the
Rohde & Schwarz SMJ100A vector signal generator or
equivalent.
• Use narrow resolution bandwidth (RBW) and engage
video averaging on the spectrum analyzer to lower the
displayed average noise level (DANL) in order to improve
sensitivity and to increase dynamic range. The trade-off
is increased sweep time.
• Spectrum analyzers can produce significant internal dis-
tortion products if they are overdriven. Generally, spectrum
analyzers are designed to operate at their best with about
–30dBm to –40dBm at their input filter or preselector.
Sufficient spectrum analyzer input attenuation should be
used to avoid saturating the instrument, but too much
attenuation reduces sensitivity and dynamic range.
• Before taking measurements, the system performance
should be evaluated to ensure that:
1) clean input signals can be produced
2) the spectrum analyzer’s internal distortion is mini-
mized
3) the spectrum analyzer has enough dynamic range
and sensitivity
4) the system is accurately calibrated for power and
frequency.
• Digital modulation often requires DC coupling and flat
frequency response. For best EVM performance with
complex modulation, the RC networks at the baseband
I/Q inputs are not required.
quick start proceDure
1. Remove the demonstration circuit from its protective
packaging in an ESD-safe working area.
2. Turn off the DC power supply as well as the baseband
and LO signal sources’ outputs.
3. Connect all test equipment as show in Figure 1.
4. Make sure jumper JP1 is installed and the jumper JP2
is installed at the 1-2 position.
5. Slowly increase the supply voltage to 3.3V. Do not
exceed 3.8V.
6. Turn on the baseband signal source. Set the baseband
common mode bias to 1.4V.
7. Verify the total VCC supply current is approximately
28mA. The demonstration circuit is now turned on
and is ready for measurements.
8. Turn on the output of the LO source and apply a
492.8MHz, 0dBm CW Signal.
9. Set the baseband signal source to provide a 100kHz,
200mVP-P(DIFF) baseband input signal. The I and Q
channels should be 90° shifted and set for lower
sideband selection.
10. Measure the modulator’s RF output on the Spectrum
Analyzer at 492.7MHz.
absolute MaxiMuM input ratings
Supply Voltage ......................................................... 3.8V
Common Mode Level of BBPI, BBMI,
and BBPQ, BBMQ ...................................................2V
LOL, LOC DC Voltage ............................................. ±0.1V
LOL, LOC Input Power .........................................20dBm
Voltage on Any Pin ...........................–0.3V to VCC + 0.3V
TJMAX .................................................................... 150°C
Case Operating Temperature Range ....... –40°C to 105°C
Storage Temperature Range .................. –65°C to 150°C
CAUTION: THIS PART IS SENSITIVE TO ELECTRO-
STATIC DISCHARGE (ESD). OBSERVE PROPER ESD
PRECAUTIONS WHEN HANDLING THE LTC5599.
3
dc2091afa
DEMO MANUAL DC2091A
DeMo boarD scheMatic
VCTRL
GND
LOL
LOC
GND
TTCK
GND
VCC
EN
SDO
SDI
SCLK
CSB
GNDRF
GNDRF
RF
GNDRF
GNDRF
GNDRF
GND
BBMQ
BBPQ
BBMI
BBPI
TEMP
LTC5599IUF
25
24
23
22
21
20
19
18
17
16
J2
J6
J5
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
C4
0.01µF
L1, 39nH
C5, 15pF
C3
0.1µF
R1, 1Ω
LO
VCTRL
TTCK
TEMP
BBMI
BBPI
GND
EN
GND
SDO
SDI
SCLK
CS
RF
VCC
3.3V
VCC
FB1
330Ω AT
100MHz
DC2091 F02
BBPQ
BBMQ
R12, OPT
R2, OPT
R8
49.9Ω
C6
0.1µF
R3, 0Ω
R4, 0Ω
R5, 0Ω
R6, 0Ω
C1
4.7µF
C2, 1000pF
JP1
2 1
E2
E1
E3
E4
J1
E5
E6
J4
J3
E7
R9
49.9Ω
*
*
C7
0.1µF
R10
49.9Ω
C8
0.1µF
R11
49.9Ω
C9
0.1µF
* REMOVE THE RC NETWORK FOR BEST EVM WITH COMPLEX DIGITAL MODULATION.
Figure 2. Low Power I/Q Modulator Schematic
quick start proceDure
11. Calculate the Voltage Conversion Gain:
Gain=20•log (VRF(OUT)(50Ω) / VIN(DIFF)(I OR Q))
12. Measure the Output 1dB Compression Point by increas-
ing the input signal level until the Voltage Conversion
Gain degrades by 1dB.
13. Measure the Image Rejection at 492.9MHz.
14. Measure the LO Leakage at 492.8MHz.
15. Connect the DC590B to the DC2091A with the ribbon
cable provided. Make sure jumper JP6 on the DC590B
is set to 3.3V.
16. Run QuikEval
®
to start the GUI associated with the
LTC5599.
17. The turn off procedure is the reverse of the turn on
procedure. Make sure VCC is removed after VEN.
4
dc2091afa
DEMO MANUAL DC2091A
Figure 3. Demo Board SPI Interface
R14
4.99k
R13
4.99k
R15
4.99k
R18
4.99k
ISO_7V_UNREG
ISO_5V_3p3v_REG
ISO_CSb
ISO_SCK_SCL
ISO_SDA_MOSI
ISO_MISO
EE_VCC
EE_SDA
EE_SCL
EE_GND
GPI01
ISO_GND
ISO_GND
ISO_GND
13
8
3
P1
HD-2X7.0.79
1
2
6
4
7
5
10
9
11
12
14
A0
A1
A2
VSS
VCC
WP
SCL
SDA
U2
24LC025
1
2
3
4
8
7
6
5
VCC_B
DIR
VCC_A
GND
U4
74LVC1T45GW
6
5
4
1
2
3
C18
2.2pF
R20
100Ω
R19
1k
C15
0.1µF
C16
0.1µF
C17
0.1µF
C14
0.1µF
VCC
VCC_L
VCC_L
VCC_L
GND
U3
NC7WZ17P6X
6
4
5
1
3
2
C13
2.2pF
R26
1k
C11
0.1µF
VCC
VCC_L
GND
U5
NC7WZ17P6X
6
4
5
1
3
2
C12
2.2pF
C10
2.2pF R25
1k
R23
1k
R22
200k
SDO
SDI
SCLK
CS
VCC_L
VCC
VCC_L
JP1
1
2
3
DC2091 F03
E8
DeMo boarD scheMatic
5
dc2091afa
DEMO MANUAL DC2091A
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
parts list
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C1 CAP., X5R, 4.7µF, 10%, 16V, 0603 MURATA, GRM188R61C475KAAJD
2 1 C2 CAP., C0G, 1000pF, 5%, 50V, 0402 MURATA, GRM1555C1H102JA01D
3 10 C3, C6–C9, C11, C14–C17 CAP., X7R, 0.1µF, 10%, 16V, 0402 MURATA, GRM155R71C104KA88D
4 1 C4 CAP., X7R, 0.01µF, 10%, 16V, 0402 MURATA, GRM155R71C103KA01D
5 1 C5 CAP., COG, 15pF, 5%, 50V, 0402 MURATA, GRM1555C1H150JA01D
6 4 C10, C12, C13, C18 CAP.,COG, 2.2pF,+/-.1pF, 25V, 0402 MURATA, GRM1555C1E2R2BZ01D
7 5 E1, E2, E3, E7, E8 TESTPOINT, TURRET, .094" MILL-MAX, 2501-2-00-80-00-00-07-0
8 3 E4, E5, E6 TESTPOINT, TURRET, .063" MILL-MAX, 2308-2-00-80-00-00-07-0
9 1 FB1 FERRITE BEAD, 33Ω @100MHz TDK, MPZ1608S331AT
10 1 JP1 HEADER, 2 PIN, 0.079 SINGLE ROW SULLINS, NRPN021PAEN-RC
11 1 JP2 HEADER, 3 PIN, 0.079 SINGLE ROW SULLINS, NRPN031PAEN-RC
12 2 XJP4, XJP5 SHUNT, 2mm Ctrs. SAMTEC, 2SN-BK-G
13 6 J1–J6 CONN., SMA, 50Ω, EDGE-LANCH E.F.JOHNSON, 142-0701-851
14 1 L1 IND., 39nH, 0402HP COILCRAFT, 0402HP-39NXJLU
15 1 P1 HEADER, 2X7PIN, 0.079CC MOLEX, 87831-1420
16 1 R1 RES., CHIP, 1Ω, 1%, 0402 VISHAY, CRCW04021R00FNED
17 0 R2, R12 OPT, 0402
18 4 R3, R4, R5, R6 RES., CHIP, 0Ω, 0402 VISHAY, CRCW04020000Z0ED
19 4 R8, R9, R10, R11 RES., CHIP, 49.9Ω, 1%, 0402 VISHAY, CRCW040249R9FKED
20 3 R13, R14, R15 RES., CHIP, 4.99K, 1%, 0402 VISHAY, CRCW04024K99FKED
21 5 R18, R19, R23, R25, R26 RES., CHIP, 1K, 1%, 0402 VISHAY, CRCW04021K00FKED
22 1 R20 RES., CHIP, 100Ω, 1%, 0402 VISHAY, CRCW0402100RFKED
23 1 R22 RES., CHIP, 200K, 1%, 0402 VISHAY, CRCW0402200KFKEA
24 1 U1 IC., LTC5599, QFN-24-4X4 LINEAR TECHNOLOGY, LTC5599IUF#PBF
25 1 U2 IC, EEPROM 2KBIT 400KHZ 8TSSOP MICROCHIP TECH., 24LC025-I/ST
26 2 U3, U5 I.C., DUAL BUFFER SCHMT TRIG UHS SC706 FAIRCHILD SEMI., NC7WZ17P6X
27 1 U4 I.C., DUAL TRANSCEIVER 3ST 6TSSOP NXP, 74LVC 1T45GW,125
28 1 FAB, PRINTED CIRCUIT BOARD DEMO CIRCUIT DC2091A
6
dc2091afa
DEMO MANUAL DC2091A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com
LINEAR TECHNOLOGY CORPORATION 2014
LT 1115 REV A • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LT C ) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LT C for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LT C from all claims
arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LT C assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LT C currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LT C applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
