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  1. #1
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    finding equivalent resistance looking into drain and source

    hi friends.
    can u please tell me how to find equivalent resistance lookin into drain and also looking into source for an mos amplifier circuit

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    Re: finding equivalent resistance looking into drain and sou

    Analog Cmos design by Razavi has given the method of diong it.Draw the small signal model of MOS ,apply test voltage at drain shorting your input and look for the value of current flowing intio drain.You will find it as ro(resistance due to channel length modulation )and for looking into source it will be 1/gm using the same method.



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    Re: finding equivalent resistance looking into drain and sou

    How to simulate it using hspice ?



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  4. #4
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    finding equivalent resistance looking into drain and source

    i think ".tf" maybe could give you the answer



  5. #5
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    finding equivalent resistance looking into drain and source

    just apply and input current and then measure the ratio: vds/id,for a particular size of your transistor. In eldo this is a simple script in measures. In cadence you may need to use skill


    amarnath



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