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    how to do dc mismatch analysis in virtuoso spectre(IC615)

    I designed folded cascode opamp for gain of 57db and UGB 16Mhz.i want to to do dcmatch analysis for folded cascode op-amp.when i am doing dcmismatch analysis in spectre it is asking threshold value.I don't know how much value to give .i am using UMC 180nm technology in that i don't know how to include variations in model file for dc mismatch analysis.....
    here i am attached a schematic of folded casode op amp..
    please help me in this regard...
    Last edited by subbareddy434; 7th June 2013 at 09:07.

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    Re: how to do dc mismatch analysis in virtuoso spectre(IC615)

    Quote Originally Posted by subbareddy434 View Post
    ... i want to to do dc mismatch analysis for folded cascode op-amp.when i am doing dcmismatch analysis in spectre it is asking threshold value.I don't know how much value to give .i am using UMC 180nm technology in that i don't know how to include variations in model file for dc mismatch analysis.....
    If fabs/foundries provide a Monte Carlo mismatch setup for their process, they usually define either threshold limits or parameter variations with variation type and standard deviation values, s. e.g. slides 11-13 of the MC tutorial below. If you don't have such a setup, just give an estimated threshold value for the offset.



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    Re: how to do dc mismatch analysis in virtuoso spectre(IC615)

    thanks for reply should i include mc model file for to do dcmatch analysis...
    Here i am attaching the snapshot of mc files which are in my foundry library. could you suggest in which i have to include variations..
    Last edited by subbareddy434; 7th June 2013 at 09:08.



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    Re: how to do dc mismatch analysis in virtuoso spectre(IC615)

    Just include the MC model files and define a variable sigma=3 in spectre.



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    Re: how to do dc mismatch analysis in virtuoso spectre(IC615)

    thanks for reply..
    I am using cadence IC615 and did n't find any option in my spectre window...



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    Re: how to do dc mismatch analysis in virtuoso spectre(IC615)

    In ADE (or ADEXL) there should be a menu "Variables" => Edit. Give the variable name as sigma and value as 3.



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    Re: how to do dc mismatch analysis in virtuoso spectre(IC615)

    thanks for reply...
    To do mismatch analysis which one i have to use it means whether ADE L or ADEXL
    could u give detailedsteps to do mismatch analysis in ADE



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