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NGSPICE gives wrong results!

  1. Apr 18, 2012 #1
    I was trying to simulate basic inverter with mosis IBM 65nm model file (lvl 54 BSIM 4.3.0). And I am getting a delay of 4ns whereas I should get 8-15 ps. I dont understand why it is giving me wrong results. I suspect ngspice (ver 24) is doing it wrong.


  2. jcsd
  3. Apr 20, 2012 #2
    Bump. I even see high capacitive Miller coupling effect.
  4. Apr 22, 2012 #3

    your current circuit has transistors with L=5um and W=5um (default values). You may consider changing these to real values.

  5. Apr 22, 2012 #4
    Yeah, found the bug at last.
  6. Jun 22, 2012 #5
    For simple netlists like this, http://www.ngspice.com can be very helpful. This site allows you to run SPICE simulations from a web browser. There is also an example circuit similar to yours that may have helped to identify the problem that you were having.
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