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    [Moved]: How to remove glitches at the output of brown out detector?

    i have designed brown out detector circuit. it consists of current mirror +power on dealy+ brown out detector + comparator with hysteresis. but at the output i am getting glitches while power supply is rising and falling (appox. 3.75 us). i want to remove those glitches. can anyone tell me how to remove it?

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    Re: How to remove glitches at the output of brown out detector?

    Possibly with an RC filter and if necessary another comparator. You could also use monostables. There are several analog alternatives or you could do it with digital circuits to poll the signal and only change output after your detector is showing a stable output.

    Brian.
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    Re: [Moved]: How to remove glitches at the output of brown out detector?

    Hi,

    Why remove? Why not avoid them by a redesign?

    Klaus
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    Re: [Moved]: How to remove glitches at the output of brown out detector?

    How? what changes should i make?



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    Re: [Moved]: How to remove glitches at the output of brown out detector?

    Can you post a schematic of what you've designed so far?



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    Re: [Moved]: How to remove glitches at the output of brown out detector?

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    here is my schematic. i



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    Re: [Moved]: How to remove glitches at the output of brown out detector?

    Yikes! It's going t take some effort to reverse analyze that. Can you give a quick run-through of how it's supposed to work?



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    Re: [Moved]: How to remove glitches at the output of brown out detector?

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    Right side Vpor:
    When Vdd > vgs1+vgs2+vgs3: current will start flowing through M5 which will charge the capacitor(M6). And vourt will start tracking power supply. reset will be 1. as soon as capacitor charges till Vlow= Vd1+Vd2+Vgs4= 2V reset will be 0.
    when power supply goes down than Vlow M4 will turn off. M7 will pull Vctrl to the gnd. M8 will turn on,capacitor(M6) will discharge through M8 faster.
    left side of Vpo:
    r is comparator with hystersis. so it will compare two input and give output high or low.
    I put inverter after Vout because i required opposite output.



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