Hello,
I'm attempting to run a small-signal transient analysis with an op amp macromodel that's referenced to +1kV instead of ground (0V). The input is a 10mVpp square wave and the op amp is in a G=+1 buffer configuration. See the image below for reference.
Unfortunately, I'm experiencing major convergence issues trying to run the transient analysis in Cadence compared to running the same circuit in LTSpice or TINA-TI. If I perform a DC operating point, I can see that large currents are flowing into and out of the op amp. This is not the case in the other simulators.
Does anyone have any suggestions on ways to resolve this? Are there recommended analysis parameters for a case like this where I need small-signal accuracy around a large DC bias voltage?
Thanks,
E.android
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I am not sure what you have done but I have the PSpice Model and the Tina LIB Model from the TI site and they both give the expected answers, bar a slight excess of about 1uA in the supply currents, certainly nothing like the results that you are getting. (17.2-2016.s034)
Hi,
I have also simulated your circuit and it works properly at my end. I can see small current flowing input and output (uA's). I am not getting convergence issues either.
My opinion is that you did not associate properly the symbol pins with the PSpice Model. Please check this and simulate again.
I am also using version 17.2 Hotfix 34
Regards
Thanks for the feedback guys. I'll check my model, the pin-to-symbol associations, and see if I can get better results.