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Simulators >> RF Simulators >> Linearity Sims
https://designers-guide.org/forum/YaBB.pl?num=1277180324

Message started by Mayank on Jun 21^st, 2010, 9:18pm

Title: Linearity Sims
Post by Mayank on Jun 21^st, 2010, 9:18pm

Hello,

If i want to check the linearity of my opamp, how do i determine what sims of the following or otherwise should i conduct ??

THD / Rapid IP3 / IM3 / IM2 / IM5 ??

Title: Re: Linearity Sims
Post by pancho_hideboo on Jun 24^th, 2010, 5:52am

Mayank wrote on Jun 21^st, 2010, 9:18pm:

If i want to check the linearity of my opamp, how do i determine what sims of the following or otherwise should i conduct ??

It depends on application of OPAmp.

But THD and IP3 are enough for metrics of linearity generally, although I don't know what you mean by "Rapid IP3".

IP2(IM2) have various type. On the other hand IP3(IM3) definition is unique.
What type of IP2(IM2) do you intend to evaluate ?
See http://www.designers-guide.org/Forum/YaBB.pl?num=1262010975/1#1

Also see http://www.designers-guide.org/Forum/YaBB.pl?num=1264434513/1#1

Title: Re: Linearity Sims
Post by sheldon on Jun 24^th, 2010, 7:48am

Mayank,

If you mean Spectre RF Rapid IP3 analysis then it is really a
analysis rather than a measurement. It is probably better used
as a tool to
1) Debug where there is distortion in the design, along with the
distortion summary
2) Identify the "worst-case" corners to investigate when you have a
lot of corner conditions. Or the Monte Carlo seeds[runs] to
investigate

I would probably add Spurious Free Dynamic Range to the list of
measurements, if the target application is for data converters. One
other thing to consider for your list is test frequencies, loads, etc.
to be used for characterization.

Best Regards,

Sheldon