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  3. Spectre PNOISE analysis (PMJITTER): converting voltage-mode...

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Spectre PNOISE analysis (PMJITTER): converting voltage-mode noise to phase noise

vivkr
vivkr over 12 years ago

I was trying to run multiple PNOISE analysis to observe different output points. So, I ran these as separate batch jobs using one of our local scripts, which simply takes in different cases as inputs and launches them as parallel runs.

When doing this for PNOISE (pmjitter), I ran into a hitch. I get the data all right but the PNOISE data is in form of V/sqrt(Hz) instead of sec/sqrt(Hz). At the moment, I am simply integrating the noise, taking dv/dt at the threshold crossing point and mapping the voltage noise error to jitter, but you can see that:
(a) It is hard to be sure if one hasn't made a mistake

(b) I canot see the noise summary anymore.

I also noticed that running the sims straight out of the GUI gives you the phase noise but that voltage noise cannot be found anywhere, else I might have done a reality check by comparing results.

Does Spectre run some sort of a postprocessing script after PNOISE analysis is completed? If yes, then how can I force this postprocessor to run on my data. I would like to have that noise summary.

I tried copying over all the data in the psf directory to the default psf directory produced when running the sims out of the GUI and loading results, but to no avail.

Could anyone suggest a way out of this problem? I really don't want to have to run a whole bunch of sims all out of the GUI and wait for weeks in order to see the results.

Regards,

Vivek

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  • ShawnLogan
    ShawnLogan over 12 years ago

    Hi Vivek,

     My only suggestion with respect to ADE's inability to load your batch simulation data is to make sure that the netlist directory is alongside your psf directory when your batch simulation is run. If the mapping file is not present, ADE may not be able to locate the proper nodes.

     

    Shawn

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  • ShawnLogan
    ShawnLogan over 12 years ago

    Hi Vivek,

     My only suggestion with respect to ADE's inability to load your batch simulation data is to make sure that the netlist directory is alongside your psf directory when your batch simulation is run. If the mapping file is not present, ADE may not be able to locate the proper nodes.

     

    Shawn

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