Recommended Active Bias Controller for HMC1121

Is there a recommended active bias controller similar to the HMC980 available for the HMC1121 that can handle the 2200mA drain current?

  • 0
    •  Analog Employees 
    on Jun 4, 2018 10:42 PM

    Hi,

    We do not have bias controller that go above 1.6A. However you can use 2x HMC980 to increase the supply current. Below is an example using 2xHMC980 to generate 2.4A.

     

    • Connections between the 2x HMC980:

      • Connect 2x Isense together
      • Connect 2x VDrain together
      • Connect 1x CPout to 2x Vneg
      • Use 1x resistor for Isense, and calculate resistor value for DUT Idd/

    Thanks,

    David

  • Thanks for the suggestion. I have a couple additional questions.

    1) Are both the HMC980 gates tied together?

    2) Is a series resistor required on the gate voltage for stability?

    3) Since the Vgate cannot go below -2V how should the gate voltage limiting resistors be installed per AN-1363?

  • 0
    •  Analog Employees 
    on Jun 6, 2018 7:41 PM

    1) Are both the HMC980 gates tied together?

        I believe only the top HMC980 gate is connected to the amplifier. The gate of the bottom HMC980 is left open.

    2) Is a series resistor required on the gate voltage for stability?

        2.2uF bypass capacitor is sufficient for stability.

    3) Since the Vgate cannot go below -2V how should the gate voltage limiting resistors be installed per AN-1363?

       In AN-1363, please refer to "ADJUSTING THE DEFAULT VNEG AND VGATE THRESHOLD VALUES" for    adjusting default gate voltage threshold. VGate and VNEG limiting are done through adding resistors R5, R6, R7    and R8 shown in figure 15.

  • 0
    •  Analog Employees 
    on Aug 2, 2018 4:05 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin