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    How to calculate Slew Rate for Differential folded cascode opamp.....??

    How to calculate Slew Rate for Differential folded cascode opamp.in cadence can anybody tell me ....??
    thanks in advance...

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    Re: How to calculate Slew Rate for Differential folded cascode opamp.....??

    ASHUTOSH RANE,

    After tarnsient simulation you have to do direct plot differential output signal from Results->directPlot-Transient->transient difference
    Than you can deriviate this expression to calculate slew rate of differential output.

    Or use this expression in cadence command line:
    deriv((v("/OUT1" ?result "tran") - v("/OUT2" ?result "tran")))

    Best Reguards


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    Re: How to calculate Slew Rate for Differential folded cascode opamp.....??

    thanks alex


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    Re: How to calculate Slew Rate for Differential folded cascode opamp.....??

    hi alex
    i found the derivative accoring to formula u given ....
    i got pulsed waveform Click image for larger version. 

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    now with this wave form and defination of slew rate we can find slew rate as maximum rate of change of output .....i got such a value equal to...
    SR+ =229e6.
    SR- =-227e6
    CL=1pF
    but these are very high values right ....??
    have i done any mistake in calculation of maximum slope??



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    Re: How to calculate Slew Rate for Differential folded cascode opamp.....??

    Quote Originally Posted by ASHUTOSH RANE View Post
    SR+ =229e6.
    SR- =-227e6
    CL=1pF
    but these are very high values right ....??
    have i done any mistake in calculation of maximum slope??
    SR+ =229e6 = 229 V/µs which means 7.64ns for your 1.75V step. Zoom into one of your step edges and verify!


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    Re: How to calculate Slew Rate for Differential folded cascode opamp.....??

    hi ASHUTOSH RANE

    There is no any mistake in calculation,
    all right!


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