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Simulators >> RF Simulators >> initial condition setting in oscillator simulation
https://designers-guide.org/forum/YaBB.pl?num=1112624813

Message started by Alez on Apr 4^th, 2005, 7:26am

Title: initial condition setting in oscillator simulation
Post by Alez on Apr 4^th, 2005, 7:26am

Hi all,

I am trying to simulate a VCO and I would like to set

initial condition to start it up.

What should I do in Spectre ?

Thank you for your reply,

Alez

Title: Re: initial condition setting in oscillator simula
Post by Andrew Beckett on Apr 4^th, 2005, 11:29pm

Try spectre -h ic

Title: Re: initial condition setting in oscillator simula
Post by Alez on Apr 5^th, 2005, 6:09am

thanks Andrew,

But I mean, how to set it from the "Analog Design Environment" menu.

I found one way:

Simulation --> Convergence aid --> initial condition

and also Initial condition setting in "Transient" analysis

Confusing about this ???

Title: Re: initial condition setting in oscillator simula
Post by Andrew Beckett on Apr 5^th, 2005, 10:45pm

Ah, you didn't mention that you want to know how to do it from ADE. The importance of asking the right question!

The Simulation->Convergence Aid->Initial Condition is a way of creating ic statements in the netlist, having set them up by pointing at nodes on the schematic.

The initial condition options on the transient analysis (readic, skipdc etc) are for if you have a file containing initial conditions. Doing it this way only affects the transient, whereas doing via the sim->conv->ic menu will affect all analyses (because it affects all the DC solutions), unless of course you've set the option in that analysis (ic=none - I
think that's the option off the top of my head).

Regards,

Andrew.