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Include file in spectre

sdv30

I have a very simple question.
I am trying to include a file in spectre. I have the simplest setup possible.
I am using an empty netlist (only entry is simulator lang=spectre) and using a stimulus file, where I have only one include statement:
include "RefClk.txt"
The RefClk.txt file has a pwl voltage source in spectre syntax (simulator lang=spectre at the top of the file). 
The issue is this: When I have a very low number of time/voltage pairs (e.g. 50) then the file is included and the simulation completes correctly.
When I try to include a more realistic pwl waveform with ~1000 time/voltage pairs, the simulations hangs.
Has anyone seen anything like that?
Thanks.

Parents

  • Good that it's working now.

    I'd recommend removing that options line altogether. I'd suggest starting from default accuracy settings, and setting the errpreset on the tran to be conservative if you really need to. Then if you need more accuracy than that, tighten the reltol to 1e-4 (which means 1e-5 with an errpreset of tran) - only tighten tolerances if you need to. Most people tend to over-tighten and then complain about the simulation performance because they've set them inappropriately. 

    Spectre is pretty accurate out of the box, so start from that assumption and tighten when you need it, rather than tighten just in case...

    Regards,

    Andrew.

Reply

  • Good that it's working now.

    I'd recommend removing that options line altogether. I'd suggest starting from default accuracy settings, and setting the errpreset on the tran to be conservative if you really need to. Then if you need more accuracy than that, tighten the reltol to 1e-4 (which means 1e-5 with an errpreset of tran) - only tighten tolerances if you need to. Most people tend to over-tighten and then complain about the simulation performance because they've set them inappropriately. 

    Spectre is pretty accurate out of the box, so start from that assumption and tighten when you need it, rather than tighten just in case...

    Regards,

    Andrew.

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