Ralph Hersey wrote:
>
> A formula for generating the chart was recently presented at IPCWorks
> '97 "Emperical equation for sizing copper PWB traces" by John McHardy
> and Mehendra Gandhi, Hughes Aircraft, technical paper SO6-2-1, and is in
> the form of I = k (T^0.44) (A^0.725)
>
>         Where:
>                 I is current in amps.
>                 k is a constant = 0.048 for "external", and 0.024 for
>                 "internal" conductive patterns.
>
>

Ralph:

What is T?  What is A?

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