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Simulators >> Circuit Simulators >> first transient ---> save final condition ----> second transient
https://designers-guide.org/forum/YaBB.pl?num=1408519116

Message started by devilmaysmile on Aug 20^th, 2014, 12:18am

Title: first transient ---> save final condition ----> second transient
Post by devilmaysmile on Aug 20^th, 2014, 12:18am

Hi all,

I have a requirement as follows:

1) I need to run transient analysis and save the final condition of the node.

2) Use the final condition of the first transient as the initial condition for the next analysis which is another transient analysis.

I am using Cadence Spectre.

I tried this method:

-start a transient analysis (OUTPUT PARAMETERS save all)
-start a second transient analysis (INITIAL CONDITION PARAMETERS readic -> spectre.fc)

in a very simple circuit (single RC circuit), but the final voltage of the capacitor in first transient analysis doesn't correspond to the initial condition of the second transient analysis.

Any ideas?

Thanks!!

-Devilmaysmile

Title: Re: first transient ---> save final condition ----> second transient
Post by Ken Kundert on Aug 21^st, 2014, 3:24pm

try using 'writefinal' on the first transient analysis.

-Ken

Title: Re: first transient ---> save final condition ----> second transient
Post by devilmaysmile on Aug 26^th, 2014, 1:49am

Thanks for reply, so in the first transient i have to use the value in ´writefinal´(spectre.fc) ? I write in ´readic´ the value (spectre.fc) or in other part of the option simulation?

Title: Re: first transient ---> save final condition ----> second transient
Post by Ken Kundert on Aug 26^th, 2014, 2:09pm

I cannot understand your question.