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  1. #1
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    mos varactor specification

    hi friends
    can anyone help me to understand how to calculate Ceff and Reff of MOS varactor in this circuit ?

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    •   Alt18th May 2017, 04:15

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  2. #2
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    Re: mos varactor specification

    I would not try to calculate it, but rather find a "blessed"
    SPICE model for the component. The R and C are both
    operating point dependent, include significant "make"
    tolerances and are pretty nonlinear. In fact with more
    than trivial signal amplitude the R and C will vary across
    the signal cycle and the LCR meter will display only some
    sort of average.



    •   Alt18th May 2017, 04:46

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  3. #3
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    Re: mos varactor specification

    thanks but i need analytical detail for calculate capacitance .



    •   Alt19th May 2017, 11:43

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  4. #4
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    Re: mos varactor specification

    The circuit is symbolizing a LCR measurement setup, the LCR meter will calculate Reff and Ceff for you (capacitor measurement mode Cs - Rs).

    In so far I don't understand what the problem is.



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