Hi,
        I have a little physics problem maybe someone can help me with. I'm
looking
for an equation to solve for the temperature rise in a trace with a given
amperage over
a given period of time. Here's the problem:
        A copper (inner layer) trace will have 6 amps on it (under short
circuit conditions)
for a maximum of 128 microseconds. For a given trace width and length, I can
calculate
the DC resistance. What I can't calculate is the temperature rise on that
trace over that
time. Obviously, I need to know this to ensure I don't approach the fusing
temperature
of the copper.
        I'll turn this into a science project if I have to, but I'm
wondering if anyone has
this equation at their fingertips. Thanks in advance if you do.

 Michael Hiteshew
 Lockheed Martin Launching Systems
 [log in to unmask]
 (410) 682-1259

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