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ADM811 resistive divide usage

Hi

ADM811 is very low consumption current device.

Can ADM811 use resistive divided input?

I would like to spend 1mA for resistor.

(input voltage is 24V, 100uA enough?)

ADI has more suitable device, I know.

Sorry I could not select other device.

Regards

moto

  • Hi Moto,

    In theory yes.

    as you'd expected, the input current of the device will contribute to the voltage monitoring error.

    you may use a typical input current for R1 and R2 calculation instead of zero current to reduce the error a bit. then use the max input current for worst case calculation.

    it is also recommended to have some decoupling capacitor on the input (depending on your input impedance), which may have some delay affect on the voltage monitoring so need to be taken into account.

    there is a better (lower power) part ADM6346/ADM6348, which has maximum around 1uA current and may be more suitable here.

    Ren

  • Dear Mr.Ren

    Thank you very much for prompt and helpful support.

    I worried about transient current increase or something.

    but  I'll try.

    Regards

    moto