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Simulators >> Circuit Simulators >> question about result browser
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Message started by danda821 on Jun 17^th, 2005, 11:35am

Title: question about result browser
Post by danda821 on Jun 17^th, 2005, 11:35am

I am trying to find the parasitic capacitance of the transistor. But when I check the results in result browser, there are many parameters: eg. element-info: I15.T0.cpccadg, I15.T0.cpccasg, I15.T0.cwiredb, ...cwiredg, dgdb_nfet, djdb_zvt, rbdba. I don't what is the meaning of the parameters. Is cpccadg the drain-gate cap? Where can I find the explanation of the parameters? I have check the bsim4
model of the cadence manual, but I can not find any useful information. Thanks.

Title: Re: question about result browser
Post by Andrew Beckett on Jun 17^th, 2005, 11:19pm

I suspect you have subckt models for your devices, and these are additional devices around the transistor. Those don't look like any parameters I'd expect to see for a bsim3v3.

Without knowing what your models look like, it's hard to give a precise answer. I had a quick look in a couple of popular foundry PDKs I have at hand, and neither of these seemed such models.

Regards,

Andrew.

Title: Re: question about result browser
Post by danda821 on Jun 21^st, 2005, 8:01am

I15 is a diode-conncected transistor. I am using IBM 0.13um PDK. Thanks.

Title: Re: question about result browser
Post by Andrew Beckett on Jun 21^st, 2005, 11:55am

Sorry, but that doesn't help very much. How the device is connected is neither here nor there, and I don't really have access to IBM PDKs (except some very old ones) without getting special agreements from IBM. Even then I'd need to know the precise process variant, and the device name.

This isn't a suggestion that you post the process name and device name here, since even then I won't realistically be able to get the answer for you. Try looking in the netlist to see what the name of the component is for I15, and then look in the model files to look for that component name and see what components are in that subckt. That might help more. If you then get stuck, perhaps you should ask IBM?

Regards,

Andrew.