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ERROR (SFE-23) The instance 'pm0' is referencing an undefined model or subcircuit, 'jitterevent'.

HsiuMin

I'm currently designing a dynamic comparator and would like to get the input refered noise by jitter in the pnoise simulation.

And this is my pnoise simulation setup.

 

It turns out the error SFE-23, seems like pm0 is not in the model library, so I check my input.scs file to figure out what is pm0.

But I still have no idea about pm0, do I miss something in my model library?

If so, is anyway to solve it?

Parents

  • Your Spectre version is way too old. That Spectre version is from 2015 - and the way that jitter is handled in the simulator has been revamped in the meantime (I'm slightly surprised because normally the UI adapts to only show the newer capabilities based on the version in use). I can't remember quite when it changed, but you should use more recent SPECTRE version (the release stream changed names many years ago too). Since we've had 6 major versions since the version you're using, I'd suggest you move to using SPECTRE21.1 (or SPECTRE20.1, but you might as well use the latest).

    Andrew 

Reply

  • Your Spectre version is way too old. That Spectre version is from 2015 - and the way that jitter is handled in the simulator has been revamped in the meantime (I'm slightly surprised because normally the UI adapts to only show the newer capabilities based on the version in use). I can't remember quite when it changed, but you should use more recent SPECTRE version (the release stream changed names many years ago too). Since we've had 6 major versions since the version you're using, I'd suggest you move to using SPECTRE21.1 (or SPECTRE20.1, but you might as well use the latest).

    Andrew 

Children
  • in reply to Andrew Beckett

    Thank you Andrew! I successfully finish the simulation after modifying the spectre version.
    By the way, I would like to ask the pnoise setup difference between IC5 & IC6 .


    Previously, the way we used to estimate the input referred noise of the dynamic comparator is by applying a small input difference(~100uV), and using jitter to observe the output difference cross the threshold value(10mV). Within the range of 10mV, the gain of the latch stage in the two-stage dynamic comparator is linear. Thus we can divide the output noise by this gain(10m/100u) to get the input referred noise.


    However, the IC6 setup window is quite different from IC5, the input-referred noise I get this time by jitter is around milli vol level, since the same circuit was verified with a hundred micro vol input referred noise by such a method in IC5.
    I also estimate this circuit on IC6 by choosing the noise type as timeaverage, which comes out hundred micro vol input-referred noise, which is just the same as our prior our.


    My setup of IC5 is shown below, do I mix something up which led to such a big difference in my simulation results?

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