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Simulators >> Circuit Simulators >> Simulating with long-time constants in high data-rate designs
https://designers-guide.org/forum/YaBB.pl?num=1534845465

Message started by sandman on Aug 21^st, 2018, 2:57am

Title: Simulating with long-time constants in high data-rate designs
Post by sandman on Aug 21^st, 2018, 2:57am

Hi,

I could not find a previous post that matched this, so please excuse if this has already been answered!

I have a generic circuit that transmits/receives pseudo-random data at very high data rates. It is trivial to run a transient simulation at this data-rate in Spectre, without issues.

Suppose I include, say, an integrator in some feedback loop involving said generic circuit, and the integrator has a very large time-constant (several orders or magnitude slower than the input data-stream), what might be the best method to simulate the (time-domain) behaviour of the generic circuit with the feedback loop, while simultaneously having high-speed data in signal path?

I would be equally thankful for workarounds!

cheers,
sandman.

Title: Re: Simulating with long-time constants in high data-rate designs
Post by rf-design on Aug 21^st, 2018, 4:20pm

You could benefit from a true multi-rate simulator in terms of runtime only if a small part of your circuit have fast nodes. Muti-rate is still in research and peak a decade ago. There are some but not many verification taks demanding what is more than a week runtime. So not enough return to spend on hard problems.

In your case the high-data.rate circuit consume most of CPU because it have to generate to input to the integrator.