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Modeling >> Semiconductor Devices >> vccs
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Message started by jhon on Sep 8^th, 2006, 8:11am

Title: vccs
Post by jhon on Sep 8^th, 2006, 8:11am

Hi guys,

I would like to implement a small signa equivalent circuit of a transistor with Spectre....
At the moment the main problem is the voltage controlled current source, :'(
I am defining it as follows:
source (gi gs di si) vccs gm=GM
but I would like to define also the delay time (i.e. tau, gm*exp(-jwtau)).
Do you know how I can define this delay time????? :-?

Thank u!!!!!!!!!

Title: Re: vccs
Post by Ken Kundert on Sep 8^th, 2006, 8:32am

Combine the vccs with a delay line (spectre -h delay).

-Ken

Title: Re: vccs
Post by jhon on Sep 8^th, 2006, 9:30am

Hey Spectre,

Thanks a lot for your feedback....

But I am completely new with Spectre,
how may I combine these functions?
I mean...which is the syntaxis??? :-?

Title: Re: vccs
Post by John O Donovan on Sep 8^th, 2006, 5:04pm

The syntax for all Spectre devices is the same. The get help on the delay device, use "spectre -h delay". Incidently the vccs device also has a "td" parameter which will do what you want, i.e.

source (gi gs di si) vccs gm=GM td=TAU

Again "spectre -h vccs" explains this.

Regards,
John

Title: Re: vccs
Post by jhon on Sep 9^th, 2006, 3:01am

perfect... ;)

thank u!!!!!