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PCB traces? Answered

so if i have a high current device (inductor) on a pcb? it will run somewhere around 2 amps of power. Is there a minimum trace width to keep my pcb trace from being blown up?


I actually found the answer for this type of question twice, once on the Nuts n Volts forum and once in Nuts and Volts Magazine. This is the thread. My post is the 2nd.

Remember, the 'net is an ever changing place. Links don't last forever, so go forth with trepidation. That said, most of my links there are dead. Here's my new Yahoo! Search and a link to a page with an Excel program to do what you want.


2 amps is modest. I've designed PCBs to handle ten times that.

Using 2 oz copper, you can do so very safely using 100 mil traces. (technically, using 2oz copper at an ambient temperature of 25C, you require a 40 mil trace, but ...)

I've always believed in over-engineering PCB designs, primarily because although I've designed well over a hundred PCBs professionally over years, they have not been designed for traditional commercial use (like buying a video board for your computer) where the limit is cut to the line, so to speak, and I think that for anything less than professional soldering, a wider trace is far easier to solder and less likely to require repair downstream.

If using 1oz copper, use roughly double the trace width, so a minimum of 100 mil for the 1oz copper and imo, a desired ~200mil trace.

Two amps is pretty high but I don't know of anywhere to figure the rating a trace will support.

I made a power supply once in elect. class and I made the high current traces as wide as possible and then flowed solder over them to increase their rating.  I sometimes abused the supply but never had a problem with the traces melting.