Dear colleagues,

very often, the PCB layout designers would draw the circuitry and write a note on the fab drawing asking that the copper be balanced by the PCB house, by adding non-functional copper.

The question I have is: how does the PCB house know how much copper to add and where to add it? Are there any scientific bases, some calculations, or is it based on experience? Otherwise said, if the PCB house will balance the copper, this means the warpage worries are gone, or just that there are chances it will warp less?

And to make it tougher: if we leave the latitude of choosing the right substrate and doing the balancing to the board shop, can they guarantee stable boards?

Thanks,

Ioan

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