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Capture - Model vs Page "Parameters". You cant have both?

Maviday

I've been creating some CMOS inverter projects in Capture and pushing/simulating them in Pspice and I noticed I wasn't getting correct waveform. I in this case I had a capacitor from the Breakout library whose page symbol value/name I changed to "0.1u" (Farads), and whose Pspice Model I edited by adding "C=0.1u" . This capacitor is connected to the to output in order to analyse the transition delay of the inverter.

Well long story short I was getting to fast of a response from the output waveform so I  eventually tried deleting the parameter I had specified in the Pspice Model Editor and was able to see a more realistic curve for the transition delay.

So what takes president the model or the name  value in the page graphics?

  • Both - if you have a model defined then calculated value is - value * capacitance multiplier

    if following model statement C is capacitance multiplier
    .model Cbreak CAP C=1

    So if you take a capacitor from breakout library and modify it schematic value to be 1u and leave .model statement as is - it would simulate 1uF capacitance.
    if I edit the model and change C (capacitance multiplier) in model statement to 1n then I would result into net capacitance value of 1u*1n

    You can refer PSpice reference guide - Capacitor for more details around capacitor model parameters.
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