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  3. VRM and capacitor placement in Allegro PCB PI

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VRM and capacitor placement in Allegro PCB PI

archive
archive over 19 years ago

In Allegro PCB PI, if there are many capacitors on the chosen power plane pair, it wastes time on placing the decoupling capacitors on the board in the post-simulation. Is there any way to auto-assign the capacitor to the actual placement on the board? Besides, only a VRM can be placed for a power plane pair, but if the actual VRM has multiple phases, how does the VRM be properly placed?


Originally posted in cdnusers.org by GinoChen
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  • archive
    archive over 19 years ago

    Auto-assigning PI models to capacitors used in a completed board is not supported. My recommendation is to use the Signal Model Assignment GUI to assign PI models to the capacitor types used in the design. In setup under Libray select only the capacitors from the board to be used. A small test case is attached you can explore and play with.

    Not sure I fully understand your VRM question. If with multiple phases you refer to a time domain behavior, you would have to transform this into an equivalent description in the frequency domain and customize the VRM model accordingly.
    Hope this helps. Juergen


    Originally posted in cdnusers.org by Juergen
    model_jf.zip
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