Large Signal Y-Parameter or S-parameter

Hamid,

Not sure if you've tried this recently. In MMSIM13.1, LSSP was integrated into the hb analysis form and was improved a great deal. So you might want to take a look at the workshop example:

<MMSIM141instDir>/tools/spectre/examples/SpectreRF_workshop/rfworkshop.tar.Z

unpack this and then in the doc directory, look at the PA document, and there's a lab in there on the new LSSP approach.

May not solve your problem, but it's worth checking.

Regards,

Andrew.

Thank you very much Andrew.

I will certainly check it out.

Best,

Hamid

Andrew,

Why it does not provide Y-parameters? Why only S-parameters? Does that mean that it is not accurate enough to calculate Y-parameters? Can I simple calculate them from S-parameters or the error would be too much?

Thank you very much,

Hamid

Hamid,

It probably means that nobody asked for it, not that they're not accurate.

You can enter zpm('lssp 1 1) etc in the calculator. The "Spectre RF Functions" panel in the calculator doesn't list lssp in the dropdown for spm, zpm or ypm, but if you type it in, it works...

I filed CCR 1412054 to get the calculator cyclic choice for Analysis Type enhanced to add "lssp", and CCR 1412059 to get the Direct Plot form enhanced to list Z and Y parameters. Of course, it may add more weight if you contact customer support and request custmer-specific duplicates of these (customer requests have more weight than internal requests).

Regards,

Andrew.

By the way, I don't know for certain whether the formulation that we use to convert s-parameters to z-parameters makes sense for LSSP. I didn't check to see if the results were meaningful... but we'd do that check as part of deciding whether to expose these in the calculator and direct plot form.

Regards,

Andrew.

Thanks a lot Andrew.

I have no access to support center since I am PhD student. I have to ask our technical staff to do that, which is difficult since I have to fill them in with all the information. Maybe that is another thing that Cadence need to change for the universities in order to get better feedback.

Regards,

Hamid

BTW, there is another issue. This hb-LSSP never comes out of running. I mean after having the result when I want to run another simulation it says that another simulation is still running! And each time I have to stop it to be able to run another simulation. The results are there and nothing is left for it to be still running, but it never finishes.

Best,

Hamid

Hamid,

I don't see that. What version of the simulator are you using (the subversion should appear at the top of the log file)? Of course, this might be circuit dependent so we may just need you to contact customer support with a testcase showing the problem.

Kind Regards,

Andrew.

Andrew,

Thank you very much for your responses. This is the version:

Version 14.1.0.255.isr2 64bit -- 21 Nov 2014

BTW, as I mentioned it is so difficult to contact customer service that all of us, prefer not to bother ourselves! I believe this is the Cadence decision not to let PhD students contact it.

Thank you very much,

Hamid