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  3. GMRES solver convergence issue during PNOISE analysis

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GMRES solver convergence issue during PNOISE analysis

Junyi
Junyi over 8 years ago

Hi,

I am simulating phase noise for my VCO by running HB PSS followed by Pnoise analysis.

During Pnoise analysis, I keep seeing following warning messages which make my simulation super slow:

Warning:  GMRES solver could not converge to the desired tolerance. Please try to increase krylov_size.

Could anyone tell me what is the cause of this warning and how to resolve it? 

Thanks in advance,

Junyi

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  • Quek
    Quek over 8 years ago

    Hi Junyi

    You can find the details about krylov_size in $MMSIMHOME/doc/spectreref/spectreref.pdf. Would you please try using the latest version of MMSIM (e.g. MMSIM15) and let us know if the warning is still present?


    Best regards
    Quek

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  • Quek
    Quek over 8 years ago

    Hi Junyi

    You can find the details about krylov_size in $MMSIMHOME/doc/spectreref/spectreref.pdf. Would you please try using the latest version of MMSIM (e.g. MMSIM15) and let us know if the warning is still present?


    Best regards
    Quek

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