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    Gm of transistor in hspice when it is called XM

    Hello,

    How do I use hspice to gm using XL7 when transistor is called as an instance in netlist ? For example, transistor is called as XM8 instead of M8 .

    Thanks
    Anil K.

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    Re: Gm of transistor in hspice when it is called XM

    There will me something like XM8^M1 as a device at the bottom
    of it all, which can be probed in the usual way as long as you
    "spell its name right". If you're using a GUI schematic driven
    system then probe the drain current and take a close look at
    how that's displayed (legend) or the "keep list".



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  3. #3
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    Re: Gm of transistor in hspice when it is called XM

    Thanks . I tried
    .probe xl7(xm8.m0) to plot gm of transistor but it did not work. Is there any other way to plot gm/id for a FET



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  4. #4
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    Re: Gm of transistor in hspice when it is called XM

    I have no idea what "xl7" is or is meant to do, but I would
    be looking for something like

    deriv(I(xm8.mo.d)/deriv(v(whatever_the_gate_node_is)

    in simulator-appropriate syntax for gm, and plot it vs
    the drain current (or dump them both to a spreadsheet,
    stepwise, maybe by a .print imported).

    Start simple, until you can get at the drain current
    and Vgs you're nowhere. Once you have that syntax right
    the rest should be straightforward (other than the bit about
    no idea regarding xl7).



  5. #5
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    Re: Gm of transistor in hspice when it is called XM

    oops ..my mistake . I wanted to write LX7.



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