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  1. #1
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    Resistor at input to high side current monitor IC

    Hi,
    Should resistor RP on page 1 of the HV7802 datasheet ideally be equal to the value of RA?

    HV7802 datasheet
    http://ww1.microchip.com/downloads/e...%20A062813.pdf

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    Re: Resistor at input to high side current monitor IC

    "Transient Protection
    Add a protection resistor (RP) in series with the LOAD
    pin if VSENSE can exceed 5.0V in positive sense or 600mV
    in negative sense, whether in steady state or in transient
    conditions."

    from the data sheet Rp, p = protection ...


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    Re: Resistor at input to high side current monitor IC

    Thanks yes,
    We have Rsense = 0R75, RA=1k and RB=3k3.

    I made RP=43k and readings (voltage on RB) were badly inaccurate.
    Now that we have RP=RA, the readings are good....

    ..the problem is, as you imply, we now dont have as good transient protection.

    We could make RA=RP=43k, but that makes the current really low and noise susceptibility may creep in.



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    Re: Resistor at input to high side current monitor IC

    Hi,

    What V_sense do you expect, worst case?

    Klaus
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



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