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Simulators >> Circuit Simulators >> Mixed-signal transient simulation
https://designers-guide.org/forum/YaBB.pl?num=1275350952

Message started by Ruritania on May 31^st, 2010, 5:09pm

Title: Mixed-signal transient simulation
Post by Ruritania on May 31^st, 2010, 5:09pm

Hi,

I'm having the problem of running the mixed-signal transient analysis, which is taking too long time for simulation and very inefficient for debugging and analysis. The previous run took me five more hours.

The circuit I've been building is half analog and half custom designed digital. The main circuits of the analog are amplifiers and comparators, and the digital are some combinational and sequential logics which is trying to auto-calibrate the analog circuits' gain and offsets.

I know that there's one way to speed up the simulation is to partition the circuits into analog and digital, if the digital part is at the functional level (for example, verilogA or VHDL).

Since right now both the analog and digital are transistor level, I can only set the same simulation accuracy for them in transient analysis (considering comparators are involved, the simulation accuracy must be set high enough for reasonable results). I'm wondering whether it is possible to tell the simulator (spectre) which part is the digital and which part is the analog, so that I can set their simulation accuracy separately?

OR, is there any other way to speed up the simulation in the given cases?

Thanks,
Ruri

Title: Re: Mixed-signal transient simulation
Post by bernd on Jun 1^st, 2010, 1:15am

IF you have MMSIM token licenses "Virtuoso_Multi_mode_Simulation" you
probably have access to Ultrasim, which is a FastSpice simulator.
With Ultrasim you can define the simulation accuracy, form true Spice Model equation to table based models and other speed up techniques, per instance though the configuration view with the Hierarchy Editor. For details please check the docs.

*

Title: Re: Mixed-signal transient simulation
Post by Ruritania on Jun 1^st, 2010, 8:05am

bernd wrote on Jun 1^st, 2010, 1:15am:

* bernd

Thank you, bernd.

I just checked the licenses, we do not have the Ultrasim feature ... :(

Ruri