The calculation of PCB current carrying capacity has been lack of authoritative technical methods and formulas. Experienced PCB layout
engineers can make a more accurate judgment based on personal experience. But for layout novices, it's not a problem.
The current carrying capacity of PCB depends on the following factors: line width, wire thickness (copper foil thickness), allowable temperature rise. As we all know, the wider the PCB
wiring, the greater the current carrying capacity.
But many people have a misconception, for example: suppose under the same conditions, 10 ml of wiring can withstand 1a, then 50 ml of wiring can withstand how much current? A lot of people think it's 5A. However, the current carrying capacity can not be calculated by line width multiple. Please refer to the following data provided by international authorities for your reference: