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
BIAS CONTROLLERS - CHIP
1
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
General DescriptionFunctional Diagram
Typical Applications
HMC981 is an active bias controller that automatically
adjusts the gate voltage of an external amplier
to achieve constant bias current. It can be used to
bias any enhancement and depletion type ampliers
operating in Class-A regime with Drain voltages from
4V to 12V and drain currents up to 200mA, offering a
complete biasing solution.
HMC981 achieves excellent bias stability over supply,
temperature and process variations, and eliminates
the required calibration procedures usually employed
to prevent RF performance degradation due to such
variations.
All data shown herein is taken with appropriate probes.
• Microwave Radio & VSAT
• Military & Space
• Test Instrumentation
• Fiber Optic Modulator Driver Biasing
• CATV Laser Driver Biasing
• Cellular Base Station
• Wireless Infrastructure Equipment
Features
Automatic Gate voltage adjustment (No Calibration
required)
Supply Voltage: 4V to 12V
Digital Voltage: 3.3V to 5V
Controls both Enhancement and Depletion type
devices
Adjustable Drain Current up to 200mA
Sink/Source Gate Current Capability
Optional Internal negative voltage generation that
can be disabled to use external negative rail
Fast Enable/Disable
Trigger-out Output for Daisy Chain Power-Up and
Power-Down Sequencing
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
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BIAS CONTROLLERS - CHIP
2
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Electrical Specications, TA = +25°C, VDD=8V, VDIG= 3.3V, Depletion Master
Unless Otherwise Noted
Parameter Symbol Conditions Min. Ty p . Max. Units
Supply Voltage Vdd 412 V
VDD Quiescent Current IDD
VDD = 4V EN = VDIG 7 mA
EN = GND 3 mA
VDD = 8V EN = VDIG 7.5 mA
EN = GND 4 mA
VDIG Quiescent Current IDIG VDIG= 3.3 V 3 mA
VDIG= 5 V 5 mA
Negative Voltage Output VNEG -2.5 V
Oscillator Frequency FOSC 300 kHz
Voltage Reference VREF 1.42 V
Enable Input Threshold ENTHRS Vinlow 1 V
Vinhigh 1. 4 V
Switch Input Threshold SWTHRS Vinlow 1 V
Vinhigh 1. 4 V
Short Circuit Disable Input Threshold DSCTHRS Vinlow 1 V
Vinhigh 1. 4 V
VDRAIN Characteristics
DRAIN Current Adjustment Range IDRAIN SW=GND 20 80 mA
SW=VDIG 80 200 mA
DRAIN Current Change Over Digital Voltage ΔIDRAINV VDRAIN set to 8V,
IDRAIN set to 160 mA
0.4 %/V
DRAIN Current Change Over Temperature 0.02 %/C
DRAIN Range VDRAIN 412 V
VDRAIN Change Over Temperature ΔVDRAIN VDRAIN set to 8V,
IDRAIN set to 160 mA 1.5 %/C
VNEG Characteristics
Negative Voltage Output VNEG -2.5 V
VNEG Current Sink INEG VDD= 4V 0 8 mA
VDD= 8V 015 mA
VGATE Characteristics
GATE Current Supply IG -0.8 0.8 mA
VGATE Low Level VG_MIN VNEG V
VGATE High Level VG_MAX VNEG+4.5 V
VG2 Characteristics
VG2 Current Supply IG2 VG2<1.5V -0.1 0.1 mA
VG2>1. 5V -1 1 mA
VG2 Adjustment Range VG2 1VDD-1.3 V
VDIG Characteristics
Adjustment Range VDIG 3.3 5 V
VDIG Quiescent Current IDIG
VDD= 8 V,
VDIG=EN =3.3 V
3mA
SW Characteristics
Internal Switch Resistance RDS_ON SW= GND 10 Ohm
SW=VDIG 5Ohm
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
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BIAS CONTROLLERS - CHIP
3
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Load Regulation @ VDD=8V,
SW=VDIG=3.3V
IDRAIN vs. VDIG[1][2]
Load Regulation @ VDD=6V, VDIG=3.3V,
SW=GND
4.5
5
5.5
6
6.5
20 30 40 50 60 70 80
+25C
+85C
-55C
IDRAIN (mA)
VDRAIN (V)
6.5
7
7.5
8
8.5
80 100 120 140 160 180 200
+25C
+85C
-55C
IDRAIN (mA)
VDRAIN (V)
VNEG Load Regulation @ VDD=4V
VNEG Line Regulation vs. Supply Voltage
-2.55
-2.53
-2.51
-2.49
-2.47
-2.45
4 6 8 10 12
+25C
+85C
-55C
SUPPLY VOLTAGE (V)
VNEG (V)
No load condition
-2.7
-2.6
-2.5
-2.4
-2.3
0246810
+25C
+85C
-55C
INEG (mA)
VNEG (V)
VNEG Load Regulation @ VDD=12V
-2.7
-2.6
-2.5
-2.4
-2.3
0 4 8 12 16
+25C
+85C
-55C
INEG (mA)
VNEG (V)
50
51
52
53
54
55
3.3 3.7 4.1 4.5 4.9
+25C
+85C
-55C
VDIG (V)
IDRAIN (mA)
[1] IDRAIN is set to 53 mA
[2] HMC465LP5 is used as external amplier
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
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BIAS CONTROLLERS - CHIP
4
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Enable Waveform
-8
-6
-4
-2
0
2
4
6
8
024681012
EN
VDRAIN
VG2
VNEG
VGATE
VOLTAGE (V)
TIME (ms)
Disable Waveform
-8
-6
-4
-2
0
2
4
6
8
12 14 16 18 20
EN
VDRAIN
VG2
VNEG
VGATE
VOLTAGE (V)
TIME (ms)
Power Up Waveform
-4
-2
0
2
4
6
8
0 10 20 30 40 50
VDD
VDRAIN
VDIG
VG2
VNEG
VGATE
VOLTAGE (V)
TIME (ms)
Shutdown Waveform
-4
-2
0
2
4
6
8
0 20 40 60 80 100
VDD
VDRAIN
VDIG
VG2
VNEG
VGATE
VOLTAGE (V)
TIME (ms)
-2.8
-2.3
-1.8
-1.3
-0.8
-20
-10
0
10
20
0 0.5 1 1.5 2
VNEG (V)
INEG (mA)
TIME (ms)
-2.55
-2.525
-2.5
-2.475
-2.45
-2.425
-2.4
-15
-10
-5
0
5
10
15
0 0.5 1 1.5 2
VNEG (V)
INEG (mA)
TIME (ms)
VNEG Load Transient VDD=4V VNEG Load Transient VDD=6V
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BIAS CONTROLLERS - CHIP
5
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
-3
-2.5
-2
-1.5
-1
-0.5
0
0.5
1
-1.25 -1 -0.75 -0.5 -0.25 0 0.25 0.5 0.75 1 1.25
+25C
+85C
-55C
IG (mA)
VGATE (V)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
-2 -1.5 -1 -0.5 0 0.5 1 1.5 2
VG2=0.9V
VG2=1.78V
VG2=2.74V
VG2=3.71V
IG2 (mA)
VG2 (V)
VGATE Load Regulation @ VDD=6V VG2 Load Regulation @ VDD=6V
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
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BIAS CONTROLLERS - CHIP
6
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Outline Drawing
Absolute Maximum Ratings [1]
VDD 12V
VG2_CONT, VDRAIN -0.5V to VDD + 0.5V
SW, EN, CP_OUT, VGATEFB,
VNEGFB, TRIG_OUT, DISBL_SC,
ISENSE
-0.5V to VDIG + 0.5V
VDIG 5.5V
VNEG -4V to GND
VG2 -0.5V to VDD + 0.5V
Junction Temperature 125 °C
Continuous Pdiss (T = 85 °C)
(Derate 19.19 mW/°C above 85 °C) 0.77 Watts
ELECTROSTATIC SENSITIVE DEVICE
OBSERVE HANDLING PRECAUTIONS
Thermal Resistance (RTH)
(Junction to package bottom) 52 .1 °C/W
Storage Temperature -65 to +150 °C
Operating Temperature -55 to +85 °C
ESD Sensitivity (HBM) Class 1B
Note that there are two different voltage domains on HMC981; a
high voltage domain Vdd, and a low voltage domain VDIG. Take
necessary precautions not to violate ABS MAX ratings of each
subdomains.
NOTES:
1. ALL DIMENSIONS IN INCHES [MILLIMETERS]
2. DIE THICKNESS IS 0.010 (0.254)
3. TYPICAL BOND PAD IS 0.0039 SQUARE
4. BOND PAD METALLIZATION: ALUMINUM
5. NO BACKSIDE METAL
6. NO CONNECTION REQUIRED FOR UNLABELED BOND PADS
7. OVERALL DIE SIZE IS ±.002
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
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BIAS CONTROLLERS - CHIP
7
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Pad Descriptions
Pad Number Function Description Interface Schematic
1, 5, 8, 10,
13, 15, 20,
23, 25, 26,
Die Bottom
GND These pads and the die bottom must be connected to a
high quality RF/DC ground.
2EN Enable pad. System is enabled when Ven is HIGH (VDIG).
If left oating, Ven defaults to HIGH (enabled).
3SW Internal switch resistance control pad. If left oating, VSW
defaults to HIGH.
12 DISBLSC Disables short circuit lock down when pulled to ground.
Leave it oating to enable short circuit lock down.
4VG2CONT
Control voltage of the VG2. Use a resistor divider between
VDD and GND to set the voltage. VG2 is typically 1.3V
lower than the VG2CONT
19 VG2 Second gate control.
6-7, 29-30 VDD, VDIG Bias supply pan. Connect supply voltage
to this pad with appropriate ltering.
9VREF 1.5V reference voltage. 0.1uF or greater capacitor to GND
is needed for noise ltering.
11 ISENSE
To adjust the bias current of the external amplier connect
a resistor (Rsense) from ISENSE pad to GND. Use Eqn.2
to
determine the required Rsense value.
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
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BIAS CONTROLLERS - CHIP
8
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Pad Number Function Description Interface Schematic
14 TRGOUT
Trigger out signal. Generates a HIGH (3.5V) signal when
the active bias system stabilizes. This signal can be
used to trigger next device (ENABLE) if more than one
HMC981 is used in a daisy chain.
16, 17 VDRAIN
Drain voltage. Should be connected to the supply
terminal of the external amplier. A minimum 100 nF
capacitor has to be placed close to the external amplier to
improve load regulation.
18 VGATE
Gate Control pad for external amplier. Connect to the gate
(base) of the external amplier. In order to guarantee
stability,a 10μF capacitor should be connected between
the gate (base) terminal of the external amplier and GND
as close to the amplier as possible.
21 VNEG
Negative input to the chip. Should be supplied with CPOUT
when negative voltage generator is enabled, or connect to
external VSS when negative voltage generator is enabled.
For detailed usage please refer to the “Negative Voltage
Generator” section.
22 VNEGFB
Feedback (Control) pad for Negative Voltage Generator
Charge Pump. Float to activate the negative voltage
generator / Sort to GND to disable the negative voltage
generator.
24 VGATEFB
Control pad for VGATEFB. Float VGATEFB when a
depletion mode transistor is biased. Selects the mode of
operation along with VNEGFB pad. For detailed usage
please refer to the Table 2.
27, 28 CPOUT
Negative voltage generator charge pump output. Negative
voltage generator needs a ying capacitor, a reservoir
capacitor and two diodes to operate. Please refer to the
application schematic for more info.
Pad Descriptions (Continued)
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
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BIAS CONTROLLERS - CHIP
9
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Application Circuit
Notes:
[1] Adjust R10 with respect to equation (2).
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
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BIAS CONTROLLERS - CHIP
10
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Mounting & Bonding Techniques for MMICs
The die should be attached directly to the ground plane with epoxy (see HMC general Handling, Mounting , Bonding Note).
Handling Precautions
Follow these precautions to avoid permanent damage.
Storage: All bare die are placed in either Waffle or Gel based ESD protective containers, and then sealed in an ESD protective
bag for shipment. Once the sealed ESD protective bag has been opened, all die should be stored in a dry nitrogen environment.
Cleanliness: Handle the chips in a clean environment. DO NOT attempt to clean the chip using liquid cleaning systems.
Static Sensitivity: Follow ESD precautions to protect against ESD strikes.
Transients: Suppress instrument and bias supply transients while bias is applied. Use shielded signal and bias cables to minimize
inductive pick-up.
General Handling: The chip may be handled by a vacuum collet or with a sharp pair of tweezers.
Mounting
Epoxy Die Attach: Apply a minimum amount of epoxy to the mounting surface so that a thin epoxy llet is observed around the
perimeter of the chip once it is placed into position. Cure epoxy per the manufacturer’s schedule.
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BIAS CONTROLLERS - CHIP
11
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Application Notes
Detailed Description
The HMC981 is a fully-integrated Active Bias Controller (ABC) that automatically adjusts the gate voltage of ampliers
operating in the Class-A regime. With an internal feedback the automatic gate voltage control achieves constant
quiescent bias through the amplier under bias, independent of temperature and amplier threshold variations. The
quiescent current is adjusted with a resistor connected externally. The HMC981 employs an integrated control circuitry
to achieve safe power-up and power-down sequencing of the targeted amplier. The HMC981 can provide auto-bias
solution virtually any amplier in the market (both enhancement and depletion type) with a quiescent current of up to
200 mA and a supply voltage of up to 12V.
The HMC981 has an integrated negative voltage generator to synthesize negative voltages required to drive depletion
mode ampliers. If an external negative supply is already available or an enhancement mode device is targeted, the
negative voltage generator can be disabled.
The HMC981 achieves excellent bias stability over supply and temperature variations with low supply voltage down
to 4V. The gate control can both sink and source current (±0.8 mA) to achieve constant bias current over input power
variations applied to the amplier. The HMC981 also generates a second gate voltage (VG2). VG2 can be adjusted
through a resistor divider connected to VDD for ampliers which require second gate voltage.
The HMC981 ensures the protection of the external amplier during turn on/off by adjusting the sequence of VDRAIN,
VGATE and VG2 outputs. HMC981 controls the bias current of the amplier under bias with the gate control driver. The
current passing through the amplier is continuously sampled and is used to control the VGATE voltage connected to
the gate of the amplier.
The HMC981 employs a SW pad to control RDS_ON resistance of the internal switch between VDD and VDRAIN.
Refer to the section under the “Supply and Drain Voltage” section for details.
The HMC981 has a built-in short circuit protection feature to protect both itself and the amplier under bias against
short circuit conditions at the VDRAIN output. Refer to the section under the “Short Circuit Protection” section for
details.
Digital Power Supply (VDIG)
The HMC981 requires an external low voltage bias rail (3.3V to 5.0V). VDIG powers the internal logic circuitry. VDIG
draws an average of 3 mA from a 3.3V. VDIG can accept voltages up to 5.0V.
Supply and Drain Voltage (VDD and VDRAIN)
The VDD supply to the HMC981 is directly connected to the VDRAIN output through an internal MOSFET switch.
This internal MOSFET is controlled through power-up sequencing which ensures that no voltage is applied to drain
of the external amplier until the gate voltage is pulled down to VNEG(ensuring external amplier is pinched-off). The
VDRAIN output of the HMC981 should be connected to the drain (collector) of the amplier under bias for the active
bias control feedback and power-up/down sequencing to work.
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BIAS CONTROLLERS - CHIP
12
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
There will be a voltage drop from VDD to VDRAIN due to nite RDS_ON resistance of the internal switch. To
compensate for this voltage drop choose the VDD value as shown in equation (1).
VDD = VDRAIN + IDRAIN x RDS_ON (1)
where VDRAIN is the supply voltage of the external amplier and IDRAIN is the desired constant bias current through
the external amplier.
Note that RDS_ON resistance of the internal FET switch can be adjusted through SW pad. RDS_ON is typically equal
to 5 Ohms when SW is pulled up to VDIG, and is typically equal to 10 Ohms when SW is pulled down to GND. If SW
is left oating, it is pulled up to VDIG through an internal weak pull-up. Recommended settings for the SW position
are given in Table-1. Not using the HMC981 in the recommended settings will increase the power dissipation of the
part and may increase the part-to-part variation.
Negative Voltage Generator (VNEGOUT)
The HMC981 has an internally regulated charge pump block to generate negative voltage (VNEGOUT) required for
depletion mode devices. The HMC981 generates -2.5V at the VNEGOUT output in default conguration. It requires
two diodes and two capacitors connected externally as shown in the sample application schematics. The HMC981 is
designed to reject the ripple on the VNEGOUT by isolating VNEGOUT from the VGATE. The negative voltage is only
required for depletion mode devices, and it can be disabled through the VGATEFB and VNEGFB pads. Where an
enhancement device is targeted or a negative supply is already available in the system, simply connect the available
negative supply to the VNEG pad. See Table-2 for detail on how to set this operation mode.
Table 1. Recommended Current Range Conguration
Current Range (mA) Condition RDS_ON (Ohm)
20 to 80 SW=GND 10
80 to 200 SW=VDIG 5
Enable/Disable (EN)
The active bias control loop is enabled when EN is pulled up to VDIG, and it is disabled when it is pulled down to GND.
If EN is left oating HMC981 is enabled through an internal weak pull-up. Note that VNEG operation is independent
of EN condition. EN signal controls the operation of only VGATE, VG2 and VDRAIN outputs. When EN pulled down
to GND, the HMC981 discharges VDRAIN and VG2 down to GND and it pulls the VGATE down to VNEG. Please see
the “Active Bias Control Loop” section for detailed explanation.
Active Bias Control Loop
The HMC981 regulates the bias current (IDRAIN) of the amplier under bias through VGATE output connected to
the gate of the external amplier. In this closed loop operation the current passing through the amplier under bias is
sampled and is used to adjust VGATE to achieve constant quiescent bias through the external amplier.
The HMC981 continuously compensates for any supply, temperature, process variations and threshold drifts due to
aging. The part-to-part, temperature, and supply variation of the HMC981 is excellent. Thus, by using an accurate
sense resistor connected to the ISENSE pad, expensive calibration procedures in high volume production could be
avoided.
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
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BIAS CONTROLLERS - CHIP
13
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
The gate control of the HMC981 is designed to both sink and source current in to the gate of the targeted amplier (at
least ±0.8 mA). This unique feature is important to achieve nearly constant quiescent bias through the amplier under
varying gate current at different input power values.
The bias current passing through the external amplier can be adjusted with RSENSE, where RSENSE is the R10
connected from ISENSE to GND. Use the relation given in equation (2) to set the desired bias current through the
external amplier.
IDRAIN=32/Rsense (A) (2)
Self Protection Feature
Due to the small resistance of the internal switch FET a large amount of current may ow through the HMC981.
HMC981 limits the maximum current to protect itself under such fault conditions, by turnung of VDRAIN and VGATE.
The HMC981 will remain in this protection mode until a full power-cycle or enable/disable cycle is applied.
VNEG Fault Detection Feature
In depletion mode operation VNEG is continuously monitored against short circuit fault to GND. If VNEG rises above
a preset value (typically -1V) the system and the external amplier are disabled by pulling VDRAIN and VG2 to GND
and VGATE to VNEG. The system will stay in this stand-by mode until short fault at VNEG is xed.
Power-up and Enable Sequencing
To ensure the protection of the external amplier, the HMC981 provides a power-up sequence for enabling active bias
control loop. During start-up VDRAIN and VG2 are kept at GND while VGATE is taken to the most negative supply
available (VGATE=VNEG). This ensures that external amplier is completely pinched-off before VDRAIN is applied.
When EN signal is received, VDRAIN is applied and the active bias loop is enabled. After the VDRAIN is applied, VG2
is generated. The nal phase of the power-up sequence is completed by increasing the VGATE linearly until the set
IDRAIN value is achieved.
For power-down and disabling the same sequencing is applied in the reverse order.
Daisy-Chain Operation
HMC981 produces a trigger out signal (TRIGOUT pad#13) when VDRAIN output is enabled. This trigger signal can
be used to enable additional HMC981 chips in a chain of ampliers. The triggering sequence can be routed in any
way, from input to output, or from output to input depending on the use. Figure-1 presents a sample use of three
HMC981s in an amplication chain. Please note that, only one of the HMC981 is used to generate the negative
voltage and the remaining HMC981 is set to receive external negative voltage (which is provided from the master
HMC981). Generating negative voltage from a single HMC981 reduces the number of the components in the system,
and decreases the over all current consumption..
Please note that, to ensure proper start-up, the system enable signal should be applied to the chip that has the
negative voltage generator.
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
BIAS CONTROLLERS - CHIP
14
HMC981
v00.0611
ACTIVE BIAS CONTROLLER
Figure 1. Daisy Chain Operation
Operation Modes
HMC981 can be congured to bias both enhancement and depletion mode external ampliers. The mode of operation
can be selected by setting two pads (VNEGFB, VGATEFB) as tabulated in Table-2. The connection to the VNEGIN
should be adjusted accordingly.
In order not to bias external amplier in a wrong region, please make sure that the correct mode of operation is
selected before powering up the HMC981.
The HMC981 does not allow the internal negative voltage generator to work if an enhancement mode is selected.
Therefore, if VNEGFB is left oating while VGATEFB is grounded, HMC981 will stay in standby mode.
Please note that the external negative voltage should be between -2.5V to -3.5V for HMC981 to operate. If your
application requires negative voltages outside this range please contact Hittite application support.
Table 2 - Mode Selection
VNEGFB VGATEFB VNEGIN Description
MODE1
(Depletion/Master Mode) FLOAT F L O AT Connected to
VNEGOUT
Depletion mode transistor. Internal negative voltage generator is
active and generates -2.5V. Sample application schematic given
shown in Fig.2a.
MODE2
(Depletion/Slave Mode) GND F LO AT Connected to
External VSS
Depletion mode transistor. Internal negative voltage generator is
disabled. An external negative voltage less than -2.3V should be
connected to VNEGIN. Sample application schematic given shown
in Fig.2b.
--- FLOAT GND N/A Not allowed. HMC981 stays in standby.
MODE3
(Enhancement Mode) GND GND Connected to
GND
Enhancement mode transistor. Internal negative voltage generator is
disabled. Sample application schematic given shown in Fig.2c.
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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Figure 2a. Depletion/Master Mode Amplier Typical Application Circuit (Mode 1)
Figure 2b. Depletion/Slave Mode Amplier Typical Application Circuit (Mode 2)
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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Figure 2c. Enhancement Mode Amplier Typical Application Circuit (Mode 3)
Table 3 - List of Bias Settings for Various Hittite Ampliers
Hittite Part Number VDRAIN (V) VDD (V) IDRAIN (mA) RSENSE (kOhm) R2 (kOhm) R1 (kOhm) VG2 (V)
LNAs
HMC-ALH140 4 4.60 60 0.53 open open -
HMC-ALH216 4 4.45 90 0.36 open open -
HMC-ALH244 4 4.45 45 0.71 open open -
HMC-ALH310[1] 2.5 3.02 [1] 52 0.62 open open -
HMC-ALH311[1] 2.5 3.04 [1] 54 0.59 open open -
HMC-ALH313[1] 2.5 3.02 [1] 52 0.62 open open -
HMC-ALH382[1] 2.5 3.14 [1] 64 0.50 open open -
HMC-ALH435 5 5.30 30 1.07 5.60 51. 5
HMC-ALH444 5 5.55 55 0.58 5.09 51. 5
HMC-ALH476 4 4.45 90 0.36 open open -
HMC490 5 6.00 200 0.16 open open -
HMC490LP5 5 6.00 200 0.16 open open -
HMC504LC4B 4 4.45 90 0.36 open open -
HMC594 6 6.50 100 0.32 open open -
HMC594LC3B 6 6.50 100 0.32 open open -
HMC609 6 6.85 170 0.19 open open -
HMC609LC4 6 6.85 170 0.19 open open -
HMC752LC4[1] 3 3.70 [1] 70 0.46 open open -
HMC753LP4E 5 5.55 55 0.58 5.09 5 1. 5
HMC772LC4 4 4.45 45 0.71 open open -
Linear & Power
HMC-ABH209 5 5.80 80 0.40 open open -
HMC-ABH264 5 5.60 120 0.27 open open -
HMC-AUH317 4 4.80 160 0.20 open open -
[1] For applications below 4V supply please contact factory.
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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Hittite Part Number VDRAIN (V) VDD (V) IDRAIN (mA) RSENSE (kOhm) R2 (kOhm) R1 (kOhm) VG2 (V)
HMC-AUH318 4 4.80 160 0.20 open open -
HMC-AUH320 4 4.65 130 0.25 open open -
HMC442 5 5.43 85 0.38 open open -
HMC442LC3B 5 5.42 84 0.38 open open -
HMC442LM1 5 5.43 85 0.38 open open -
HMC499 5 6.00 200 0.16 open open -
HMC499LC4 5 6.00 200 0.16 open open -
Wideband (Distributed)
HMC-ALH482 4 4.45 45 0.71 open open -
HMC-AUH232 5 5.90 180 0.18 4.52 51. 5
HMC-AUH249 5 6.00 200 0.16 4.38 51. 5
HMC-AUH312 8 8.60 60 0.53 2.82 51. 8
HMC460 8 8.60 60 0.53 open open -
HMC460LC5 8 8.75 75 0.43 open open -
HMC463 5 5.60 60 0.53 open open -
HMC463LH250 5 5.60 60 0.53 open open -
HMC463LP5 5 5.60 60 0.53 open open -
HMC465 8 8.80 160 0.20 2.33 51. 5
HMC465LP5 8 8.80 160 0.20 2.33 51. 5
HMC562 8 8.80 80 0.40 open open -
HMC633 5 5.90 180 0.18 open open -
HMC633LC4 5 5.90 180 0.18 open open -
HMC634 5 5.90 180 0.18 open open -
HMC634LC4 5 5.90 180 0.18 open open -
HMC-930 10 10.88 175 0.18 3.95 5 3.5
Microwave & Optical Drivers
HMC870LC5 7 7.83 165 0.19 open open -
HMC871LC5 8 8.38 75 0.43 open open -
Table 3 - List of Bias Settings for Various Hittite Ampliers (Continued)
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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Notes: