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Simulators >> Circuit Simulators >> how to plot gm/I0 and fT/I0 in analog artist
https://designers-guide.org/forum/YaBB.pl?num=1111161744

Message started by nus_lin on Mar 18^th, 2005, 8:02am

Title: how to plot gm/I0 and fT/I0 in analog artist
Post by nus_lin on Mar 18^th, 2005, 8:02am

Dear guys,

I am using cadence, analog artist. the simulator i use is spectre. Now i need to sweep I0 and plot the change of transconductance and other parameters as the position of poles. can anybody told me how to do that?

there is an option like "setup output" from the pop-up window of simulator, is is the correct access to the parameters like gm, cgs,cgd?

Title: Re: how to plot gm/I0 and fT/I0 in analog artist
Post by Andrew Beckett on Mar 20^th, 2005, 2:35am

This has come up a few times. A quick search (using the search button at the top of the Forum), for "gm sweep", setting the maximum post age to 600 days,
gave this (amongst others):

http://www.designers-guide.org/Forum/?board=circuit;action=display;num=1079491622;start=1#1

Regards,

Andrew.

Title: Re: how to plot gm/I0 and fT/I0 in analog artist
Post by nus_lin on Mar 20^th, 2005, 10:57pm

Many thanks to you, andrew. but can you tell me more detail about where to put the include file? is there any old include file for spectre simulator? i cann't find any include file in my working directary, :-[.

Title: Re: how to plot gm/I0 and fT/I0 in analog artist
Post by Andrew Beckett on Mar 20^th, 2005, 11:09pm

If you're using the analog design environment, choose Setup->Model Libraries, and then add the included file there. You can put it wherever you want, if you give the path to the file. Or you can set an include path (on the Setup->Simulation Files form) and then give a relative path on the model libraries form.

Regards,

Andrew.

Title: Re: how to plot gm/I0 and fT/I0 in analog artist
Post by smchiu on Jul 23^rd, 2006, 1:34am

Hi Andrew,

May I by the way ask a similar question on this?

I want to plot gm/I vs Vgs-Vt instead of just vs Vgs. In Hspice, I use to use a command called .probe with PAR to set Vgs - Vt to a certain single variable to plot it. However, in SPECTRE, I am not sure what to do. Please advice.

Thanks a lot.
David.

Title: Re: how to plot gm/I0 and fT/I0 in analog artist
Post by ADDA on Jul 24^th, 2006, 6:19am

You can use caculator to get what you want.

smchiu wrote on Jul 23^rd, 2006, 1:34am: