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Design >> Analog Design >> Displaying GM/ID vs ID/(W/L)
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Message started by mahno on Aug 22^nd, 2007, 8:11am

Title: Displaying GM/ID vs ID/(W/L)
Post by mahno on Aug 22^nd, 2007, 8:11am

Hello

I would like to know how I can display GM/ID vs ID/(W/L) using Spectre.

I did this in ADS but I do no know how to do it in Spectre-Cadence.

In ADS I did a DC sweep (sweep VGS)

for each value of the VGS (for VGS>Vt) I ran an AC sweep (Just a few frequency points) (parametric AC analysis)

After that I just did some math with these results. (The first point of the AC sweep is a very low frequency, 0 or 1Hz for example, and the value of id amplitude is GM assuming a 1V amplitude for the vac applied on VGS)

Title: Re: Displaying GM/ID vs ID/(W/L)
Post by nxing on Aug 24^th, 2007, 9:29am

IN Cadence, you can do the DC analysis and use the calculator to plot the DC "parameter" and do the calculation.

Good Luck!