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Simulators >> Circuit Simulators >> dc sweep on two sources
https://designers-guide.org/forum/YaBB.pl?num=1052837784

Message started by mike mcfarland on May 13^th, 2003, 7:56am

Title: dc sweep on two sources
Post by mike mcfarland on May 13^th, 2003, 7:56am

hey is it possible to get spectre to dc sweep two sources and then plot the curves with awd? like i'm trying to get output characteristics for this transistor and i just want to sweep vds for different values of vgs. is it even possible to do this from the analog artist window in cadence's icfb software? (doesn' t look like it so i just went and tried to do it from spectre directly with equally little luck)

thanks

Title: Re: dc sweep on two sources
Post by Eugene on May 13^th, 2003, 10:28am

I would try the Parametric Plotter. It's fairly straightforward to use. I would set up one sweep in the DC analysis then use the parametric tool to do the other. I think you can even perform both sweeps from the parametric tool if you wish.

Title: Re: dc sweep on two sources
Post by Andrew Beckett on May 14^th, 2003, 6:22am

In spectre itself, something like this would do the trick:

Code:

* Author A.D.Beckett
*
* Noddy analysis to generate id vs vds and vgs curves for a simple
* level 1 transistor.
*

model nch mos1 type=n vto=1 kp=16u gamma=1.3 lambda=0.01 \
phi=0.7 pb=0.80 mj=0.5 mjsw=0.3 cgbo=200p cgso=350p cgdo=350p \
cj=300u cjsw=500p ld=0.1u tox=80n \
af=1 kf=3.1e-24

m1 (drain gate 0 0) nch w=20u l=0.8u
vgs (gate 0) vsource dc=1
vds (drain 0) vsource dc=1

save m1:ids

sweepvgs sweep dev=vgs param=dc start=0 stop=2 step=200m {
dcAnalysis dc dev=vds start=0 stop=5 step=20m
}

However, as has been noted, you can do this with a combination
of a dc sweep in artist (of the vds, say), and then use the Tools->Parametric analysis to sweep the vgs (you'll need to put a design
variable on the vgs voltage source to do that though).

Regards,

Andrew.