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Question about HMC590


My customer is testing the performance of HMC590, but the result isn't good.

So they ask some questions about using HMC590.

Please refer their test results and let me know your opnions.

Below is only a unit test result.

1)  Gain is measured to 14dB.  

     - S22 is about -4dB and S11 is about -8dB.

2) In case of adding RF matching inductor (19uH) at VDD Bias, Gain value is increased.

    For the lack of allowable current, they can't use this inductor.

Q1) For increasing Gain value, which components can they add to VDD Bias ?

      Or how do they modify this curcuit for getting better gain?

Q2) Below are their HPA circuit and HPA power circuit.

      Would you confirm below circuit diagram and let  ne know your opinions?

Pleae advise me.



  • Hello,

    Would you  let me know your status about this questions?

    This is very urgent issue , so they are asking your status everyday.

    Please let me know your opinions ASAP.

    If you have any confusion about above questions, please let me know.

    I will check to my customer and let you  know quickly.



  • Can I get the following information

    1. Operating Frequency,

    2. Vgg voltage

    3. Quiescent drain current 

  • Dear enash,

    Thank you your kind concern about this issue.

    Please refer answers about your questions.

    1. Operating Frequency,

     -> 7GHz ~ 8.5GHz

    1. Vgg voltage

     -> -0.13V

    1. Quiescent drain current 

     -> 820mA



  • Hi Se-woong,

    I'm not sure what is going wrong here. There is always the possibility that the part is damaged. I see that you have set the quiescent current to the correct level.  The gate voltage seems a little high, that is, closer to 0V than I would expect,  but it's not out of bounds. How are they measuring gain and return loss? Is this on their own board or on the ADI evaluation board. Is it possible that there is an issue with calibration of the setup? They should not need to be adding inductors to achieve the specified gain of just over 20 dB.