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    Extracting model for MOSFET

    Hi, as I mentioned in one of my other posts, I was told that to reduce the time taken by the harmonic simulation it is good to use the model for the MOSFET.
    I am not sure whether I can find this model in PDK. Where do we usually find and extract this model from PDK.

    I think something like this is what I am looking for https://www.oreilly.com/library/view...2/bapp01.xhtml

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    Re: Extracting model for MOSFET

    Quote Originally Posted by circuitslave View Post
    Hi, as I mentioned in one of my other posts,
    I was told that to reduce the time taken by the harmonic simulation
    it is good to use the model for the MOSFET.
    No.
    Simply your simulation settings are not appropriate.

    Why do you set oversampling factor as 9 ?
    Can you understand Harmonic Balance Analysis ?

    Can you understand MOSFET model which you use ?
    Last edited by pancho_hideboo; 15th July 2019 at 11:47.



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    Re: Extracting model for MOSFET

    Quote Originally Posted by pancho_hideboo View Post
    Can you understand Harmonic Balance Analysis ?
    https://www.youtube.com/watch?v=BM5ZQgfb_sY

    I know whatever he said in that video. Not more than that.

    Quote Originally Posted by pancho_hideboo View Post
    Can you understand MOSFET model which you use ?
    I know about small signal model of MOSFET such as given here. https://www.google.com/search?q=smal...1XW7yooLb4bLM:

    and about its parasitics Cgs,Cds and Cgd. I know how to get its operating point details from spectre. Can you be specific what exactly I need to know about the MOSFET model I use?



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    Re: Extracting model for MOSFET

    Quote Originally Posted by circuitslave View Post
    https://www.youtube.com/watch?v=BM5ZQgfb_sY
    I know whatever he said in that video. Not more than that.
    Don't rely on such trivial video.

    Quote Originally Posted by circuitslave View Post
    I know about small signal model of MOSFET such as given here.
    You can not understand basic things at all.

    Small signal models are not useful at all.

    Quote Originally Posted by circuitslave View Post
    Can you be specific what exactly I need to know about the MOSFET model I use?
    Surely learn basic things.

    I think you use bsim3 or bsim4 at least.
    Confirm model you use.

    RF MOSFET is modeled as macro model using bsim3 or bsim4.



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    Re: Extracting model for MOSFET

    That is a dangerous thing to do.. When you are simplifying models, you are throwing away higher order effects. If you ignore higher order effects, or try to make an approximation out of it, then you will be losing crucial higher harmonic information. For example, your 2nd harmonic and fundamental often mix together to result in a component at your fundamental frequency which interferes with the operation of your circuit.



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