There is no original formula, per se.
But, UltraCAD has derived some formulas based on two data sources, of which
the IPC data is one.
See the articles (I think there are at least three of them) on our web page
(http://www.ultracad.com) and the calculator
PCBTEMP.exe
Doug Brooks
At 02:08 PM 7/2/2001 -0500, Chris Robertson wrote:
>Oh, knowledgeable ones.
>
>What exactly is the formula behind the current - trace width
>table? (Per Deg C)
>
>CR
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