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  3. Zero Diagonal Matrix in Jacobian on Net-x

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Zero Diagonal Matrix in Jacobian on Net-x

RFStuff
RFStuff over 11 years ago

 Dear All,

I am finding  Zero Diagonal Matrix in Jacobian on I0/I117/I11/I5/12/I1/net05,I0/I117/I11/I5/12/I1/net05 . It I am running with APS enabled. I know it is created because of open or shorted loop node.

But when I checked this node it is neither floating nor a short loop node.

Is there any other reasons why Zero Diagonal Matrix in Jacobian error comes ?

Kind Regards

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  • Andrew Beckett
    Andrew Beckett over 11 years ago

    This generally is an indication that you have an ill-conditioned matrix, which is often caused by having non-isolated solutions. This can be because you have floating parts of you circuit - which means there is potentially an infinite continuum of solutions, and this is a problem for convergence.

    It can also be an issue with certain loops (e.g. loops of ideal inductors, voltage sources in parallel and so on). The topology checker will find many (but not all) of these.

    I'd suggest that you contact customer support so that we can take a look at your example and give some directed advice?

    Regards,

    Andrew.

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