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    How to convert CMRR in DB to Numerical Value

    My CMRR value is 90dB. Can anyone explain to convert this in numerical value.

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    Re: How to convert CMRR in DB to Numerical Value

    90 dB = 20 * log(voltage_ratio)
    =>
    voltage_ratio = 10^(90/20) = 31623

    The output will change max 1/31623 of the input common mode change. In this case about 32uV/V


    You can also get this directly by going from out/in = -90 dB = 10^(-90/20) = 32u



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    Re: How to convert CMRR in DB to Numerical Value

    Quote Originally Posted by satiz View Post
    My CMRR value is 90dB. Can anyone explain to convert this in numerical value.
    20*log(x)=90dB
    so , x is 31633.



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    Re: How to convert CMRR in DB to Numerical Value

    Hi,

    What about doing an internet search on your own: "online dB calculator"...

    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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    Re: How to convert CMRR in DB to Numerical Value

    Online calculator gives me the results. But Mr.std_match explanation is very much useful to understanding better way :)



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