HMC981
v00.0611 ACTIVE BIAS CONTROLLER
BIAS CONTROLLERS -CHIP Typical Applications Features • Military & Space Automatic Gate voltage adjustment (No Calibration
required)
Supply Voltage: 4V to 12V • Test Instrumentation Digital Voltage: 3.3V to 5V • Fiber Optic Modulator Driver Biasing
• CATV Laser Driver Biasing Controls both Enhancement and Depletion type
devices • Cellular Base Station Adjustable Drain Current up to 200mA • Wireless Infrastructure Equipment Sink/Source Gate Current Capability • Microwave Radio & VSAT 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 Functional Diagram General Description
HMC981 is an active bias controller that automatically
adjusts the gate voltage of an external amplifier
to achieve constant bias current. It can be used to
bias any enhancement and depletion type amplifiers
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. …