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Simulators >> Circuit Simulators >> How to plot a MOS's Vth vs TEMP curve?
https://designers-guide.org/forum/YaBB.pl?num=1147336739

Message started by cirand on May 11^th, 2006, 1:38am

Title: How to plot a MOS's Vth vs TEMP curve?
Post by cirand on May 11^th, 2006, 1:38am

Can I use Spectre to get the Vth-T curve and some other MOS parameters such as mobility-T curve? and How to ?

Title: Re: How to plot a MOS's Vth vs TEMP curve?
Post by ACWWong on May 11^th, 2006, 4:17am

you can do a parametric analysis with temp and plot the operating point of the transistor from the calculator.

for example plotting:

OP("/M0","vth")

after the parametric simulation will give you what you want.

I'm not sure how you can do it using the DC sweep temp function alone.

Title: Re: How to plot a MOS's Vth vs TEMP curve?
Post by cirand on May 11^th, 2006, 8:26pm

thanks,
it works using the parameter analysis.
but using the DC temp sweep , i can get only one point, not a vth-T curve. why?...

Title: Re: How to plot a MOS's Vth vs TEMP curve?
Post by S. Badel on May 12^th, 2006, 5:20am

That's because you are picking data from the operating point analysis (dcOp) which is run once at the beginning of the simulation.

When doing a parametric sweep, you are actually running multiple simulations, so the operating point is saved for each point and you can get a curve.

as for other parameters,
getData("/M0" ?result "dcOp")~>?
will list all dc operating points parameters that are available such as gm, gds, vdsat etc.

all should be documented in the simulator's reference manual.

stéphane

Title: Re: How to plot a MOS's Vth vs TEMP curve?
Post by Marc Murphy on May 12^th, 2006, 7:57am

cirand wrote on May 11^th, 2006, 8:26pm:

thanks,
it works using the parameter analysis.
but using the DC temp sweep , i can get only one point, not a vth-T curve. why?...

Add a command to your netlist like this (via including an extra file):
save m0:all

and it will save all the swept operating points, allowing you to do the plot you want.

This works for me!

Cheers,
Marc

Title: Re: How to plot a MOS's Vth vs TEMP curve?
Post by ellarguero on Oct 26^th, 2012, 2:38pm

Hello Guys,

I face the same problem, i need to draw mobility versus Vgs
from a DC OP i simply can't find this info. there is U0 which is the mobility at zero bias , but i need to draw the dependance on Vgs

Any suggestion appreciated