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Simulators >> Circuit Simulators >> Spectre don't recognize "0" as gnd?
https://designers-guide.org/forum/YaBB.pl?num=1323182450

Message started by mjun0mjun on Dec 6^th, 2011, 6:40am

Title: Spectre don't recognize "0" as gnd?
Post by mjun0mjun on Dec 6^th, 2011, 6:40am

Hi guys,

I met a problem in my post_simulation which cost me much time. I used Calibre to extract parasitic parameters. And in the generated Calibre view I find something strange, that is, all the parasitic capacitors to ground are connected to node '0', not my ground in the design--'agnd', and the node '0' is connected to the 'agnd' through a capacitor. Part of the printscreen of the Calibre view is shown in the figure 0_gnd.JPG below. What's more, I simulate the voltage of the node '0', which is not constant zero, but changes with time. So all the simulation results are wrong. Could someone help me figure this out?

Thank you~~
Ma Jun

Title: Re: Spectre don't recognize "0" as gnd?
Post by ahutianyi on Dec 23^rd, 2011, 7:00am

I got the same problem which confused me so much.Waiting for someone to give the solution. :)

Title: Re: Spectre don't recognize "0" as gnd?
Post by rfidea on Dec 25^th, 2011, 2:39am

Try the Calibre support at Mentor Graphics!

Title: Re: Spectre don't recognize "0" as gnd?
Post by Geoffrey_Coram on Jan 11^th, 2012, 7:26am

I agree with rfidea -- it's probably a configuration setup error on your part with Calibre. Ie, maybe you're supposed to specify the name of your ground note in the setup, and it defaults to 0 because you failed to specify it.