Happy Holidays,
I am working on a backplane design that requires the ability to handle up to
50Amps. This brings to mind alot of questions.

To handle that kind of current I need a trace with a width no less than .82"
with 2oz material, or  .55" with 3oz material, with a 20 degree C
temperature rise.

1) What are the ramifications of using 2 or 3oz copper current carrying
external layers and 1 oz for internal signal layers ie warping, cost,
manufacturability, hole plating issues.

2) If I use the 2 external layers as planes with 1 or 1.5oz copper, I can
double the heat disipation area (roughly) and half the current load per
layer, but then I am concerned about current carrying capacity thru the
plated holes. What is a minimum number of holes if there were 10 pins
available at a diameter of .035 to carry the current ( 5 Amps per pin)?

Thanks for your feedback