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Simulators >> Circuit Simulators >> MOS parameters in Spectre tools Result Browser
https://designers-guide.org/forum/YaBB.pl?num=1169433434

Message started by zhangjerome on Jan 21^st, 2007, 6:37pm

Title: MOS parameters in Spectre tools Result Browser
Post by zhangjerome on Jan 21^st, 2007, 6:37pm

In dcOpInfo-info, A MOS device has parameters such as Cbb cbd cbg cbs cdb...There are parasitic capacitances from each node to all of the nodes. Generally we need Cgs to calculate the gate parasitic capacitance. But now we have Cgs/Csg. So I am confused. To calculate the node capacitance, we should use Cgs or Csg, or the sum of them??

Title: Re: MOS parameters in Spectre tools Result Browser
Post by Andrew Beckett on Jan 22^nd, 2007, 3:58am

There are quite a few posts asking similar questions (also asking about the fact that some of these parameters (which are partial derivitives with the bsim3v3 model) are negative). I suggest using the search capability of this forum to find your answer...

Regards,

Andrew.

Title: Re: MOS parameters in Spectre tools Result Browser
Post by zhangjerome on Jan 22^nd, 2007, 5:48pm

Hi, Beckett:

Thanks for your reply. I checked some related posts. So is it ture to say that the capacitances calculated by Spectre are in fact not physically exsit and I can't use Cgs /Cgd to evaluate the gate and drain capacitance??

Thank you again.

Regards

Jerome Zhang