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  3. stb analysis after tran -any options required?

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stb analysis after tran -any options required?

kenc184
kenc184 over 3 years ago

To use the final operating points in a tran sim as the basis for an stb analysis, is it as simple as making sure the tran analysis is placed above the stb analysis in Explorer?   Do I need to fiddle with any options in the stb options page like "prevoppoint"?

Incidentally, I'm simulating an adaptive bias crystal oscillator, hence the need for looking at the control loop once the final op point is reached rather than the startup op point.

And as a side note APS delivers a result I expect, that is, oscillating slightly below the parallel resonant frequency of the crystal, whereas SpectreX in AX or CX mode fails to oscillate. I have opened a ticket on this.

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  • Marc Heise
    Marc Heise over 3 years ago

    Hi,

    the "tran" analysis offers a feature called "actimes"  which let you specify timepoints within the tran runtime to do an ac/stb run. Please look it up in the docu.

    This also could be triggered by an assert measurement, so you not have to manually measure or guess the timepoint you need the ac/stb at:

    Article (20487740) Title: How to run a small signal analysis within a transient analysis at a non-specified time that is conditional to the behavior of the circuit
    URL: support.cadence.com/.../ArticleAttachmentPortal

    Kind regards,

    Marc

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  • kenc184
    kenc184 over 3 years ago in reply to Marc Heise

    Thanks! These tools continue to get more sophisticated.

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