ADUM4120 VDD2 has been tested in 250mA and 1A.

we are evaluating this P/N, for 2A+ current ability, and Switching Frequency 200Khz. Solar PV application.

Could you tell me the power supply for VDD2 of ADUM4120 recommended value? 250mA?

we use 16pcs in one board, so the total power consumption is a problem to us. and also the cost is sensitive.

So could we use {50mA or 100mA with big capacitance discharge} to instead of 250mA power supply?

pls advice. thank you very much.

if we use big capacitance, UVLO function may lost in test.

  • 0
    •  Analog Employees 
    on Jun 26, 2017 9:00 PM


    The local decoupling to the gate driver output supply is what provides the high current capability. The actual average current necessary for the gate driver as seen by the isolated power supply is averaged across the entire switching cycle, and is usually very low. For a 200 kHz switching frequency, I would estimate the average current to be around 20 to 40 mA per ADuM4120, but this is dependent on the size of the FET/IGBT being driven. The UVLO protection is designed to protect against a low power supply voltage, and is intended to protect across many cycles, and is meant to protect against a failing power supply, or one that is over loaded.

    Depending on the switch you are driving, I would guess a 100 mA secondary supply per ADuM4120 with 10µF + 0.1µF of decoupling capacitance would suffice.


  • 0
    •  Analog Employees 
    on Aug 2, 2018 3:52 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.

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