I had ported a verilogA model for MESFET device into Cadence. I successfully used this model in ADS. I see discrepancies in Sparamters sims vs. AC sims. In ADS I do not have this issue. It seems that in specrtre the gm (re(Y21)) of the device is significantly lower then extracted using AC simulation. In ADS I get identical gms independently of the type of the simulation used.

I am quite confident that I do not have a mistake in my test bench since I am using the same approach on the BSIM model, and AC and Sparam gm matches.

Any ideas? suggestions?

Thanks,
Aleksey