Features and Benefits

  • 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

Product Details

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.

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

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Tools & Simulations

Software and Simulation

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.

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The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

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