in spectre is there an equivalent of the sp*tswitch to be used in a pac simulation? For example, in an AC simulation, the sp1tswitch break a circuit in AC mode only, while for the DC point of view the switch is a short. Can I do the same thing in a PAC simulation? I.e. keeping the switch a short for the PSS simulation while being an open for PAC only and viceversa? Thank you,
No, this is not possible (nor would it be a good idea as it would break the analysis). What are you trying to do? Are you using harmonic balance or shooting mode of pss?
It's a shooting pss. I'd like to check the voltage gain in pac sampled simulation between nodes N1-N2 as in the sch drawn here https://community.cadence.com/cadence_technology_forums/f/custom-ic-design/43477/noise-jitter-transfer-function-along-clock-driven-inverter-chainI'm not sure that with a PXF sampled (with Stimuli option "nodes_and_terminals" selected) in Voltage Gain mode in the Direct Plot Form, when I select the output terminal of the first inverter, this is giving me the voltage gain between node N1 and node N2 (provided that in PXF sampled form I put the node N2 as output)...
Hi, any update on this topic? How should I perform a simulation like this?
If this is urgent, you should contact customer support. My availability is rather limited this week (I'm on vacation most of it, and at a customer yesterday and today).
Did you try using the voltage gain on the direct plot form for sampled pac? Similarly I think that using the voltage gain with nodes and terminals (you'd have to make sure you're saving the output terminal of the inverter connected to node N1) would do the right thing.
Actually thinking about it, I'm not sure measuring the voltage gain with PAC would be correct here, because that works by measuring the voltage at the numerator and denominator nodes, which would be at the sampling instant. The gain is not really instantaneous, and so the signal level at the N1 output when the output of N2 is switching is probably not terribly meaningful.