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analogy
analogy over 9 years ago

If you look at above circuit, for a time varying signal (0v -> 1v in let's say in 100 ps), dc operating points would change in this 100ps interval.We know that time varying intrinsic capacitance (particularly Cdb of PMOS and NMOS - with no body effect) will constitute the total output capacitance as,

Cout = Cload + Cdb + Cdb

Sure, if one wants to find this time varying capacitance in transient simulation we can use captab,

When selected nodetonode, one would expect to see DEVICE.D:DEVICE.B capacitance in capacitance table.But it wouldn’t show any.Is there a limitation for node capacitance feature as far as inclusion of device capacitance is concerned?

P.S. I know that one can find Cdb as operating point parameter but this would mean that one would need to make a theoretical estimate of capacitances present on output net.

 

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  • Andrew Beckett
    Andrew Beckett over 9 years ago
    Please contact customer support about this.
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  • Andrew Beckett
    Andrew Beckett over 9 years ago
    Please contact customer support about this.
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