Random fact, people who are annoyed by USians' insistance on not using metric look away
at least in the US, the standard unit of PCB plating thickness is the "ounce". A regular everyday PCB will be plated with 1oz copper, but some that need to handle higher current will have 2oz copper, and some design restrictions might mean you want 0.5oz copper
you might think this is weird because it's the thickness that matters, not the weight, but not to worry! ounce is a measure of thickness in this context. it's the thickness that results from spreading one ounce of copper over an area of one square foot
you may note that this is specific to copper, and in fact the industry standard (1 oz Cu = 34.79 μm) does not correspond to what you would get using commonly accepted values for the density of pure copper (that comes out to 34.06 μm)--that's because this definition uses a very specific alloy of copper that does not correspond to either pure copper or even the copper you would find in wires
-F
Random fact, people who are annoyed by USians' insistance on not using metric look away
@Felthry ...what? *blinks* Standards are /weird./
re: Random fact, people who are annoyed by USians' insistance on not using metric look away
@IceWolf yeah i think most people realize how ridiculous and arbitrary it is, but it has the convenience that 1ozCu is a really convenient thickness, not too thin and not too thick
you could also just call it 35 micron copper though and some people do, but most fabs still will only offer 35 micron or 70 micron, or sometimes thicker, but never intermediate thicknesses, just because it's what the engineers are used to
-F
