Hi all!

We have a board which will occasionally see current spikes when it is used
to power-up another device.  The design of the traces for the steady state
current is reasonably straight forward, so I'm comfortable with that aspect
However, I'm not sure how to be certain the traces can handle the short
duration (few milliseconds) current surges the system will see.

My "gut feeling" is that such a short duration spike shouldn't be an issue.
I'd like to find some information to collaborate that feeling though.  I'm
also wondering if there are any long term concerns about degradation of the
trace.  Over the course of the PCB's lifetime, it will be used to power up
the system many times and thus be repeatedly exposed to these brief surges.
(Not sure how many of these cycles it will see)

Does anyone know of any resources I can use to calculate if the traces need
additional width because of the spikes?  We're already pretty much at the
limit for what will fit on the board just with the steady state high current
requirements.  Any information about how many surges it could see before
reliability would begin to be a concern?

I think that covers the situation, but let me know if you need more info and
thanks in advance for any help.  Oh, this is a high-rel product and there
are no fuses to consider in this scenario.

Thanks,
Bill

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