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Platform forum

ha123 , 02-07-2025, 01:23 AM

I have a power pin wired to a 2.54 header pin. When I was designing the PCB, I connected it to the power plane layer in the picture attached. Three (3), 10 mil wide traces connect to the pin, all at 14 mil length each. I already have the PCB so I cannot change it now. I am using 1oz copper.

My question is can I pass 2-2.5 amps through this pin safely considering it's connected to a large copper pour?

I used a PCB current calculator and for 2.5 amps, it says I need 100 mil width of copper trace for a 20F temperature rise, but I thought maybe it will be different considering its connected to basically a heat sink.

QDrives , 02-07-2025, 04:44 PM

1oz, 10mil, 20°C rise, 22°C ambient, outer layer --> ~1.2A. You show 3, so you can do over 3A.

ha123 , 02-07-2025, 09:48 PM

I really appreciate this thank you.

Robert Feranec , 02-08-2025, 08:22 AM

for high power through hole "+" pins I often use direct connection and use thermal relief on GND through hole pins only (often there are multiple GND pins to carry high currents so the GND pins can share the high currents). usually only the GND pins connected to multiple parallel solid GND planes are problems for soldering.

BTW, don't forget to double check if a pin of that connector can carry the required current.

Also, I think because the connection in thermal relief is very short and connected to a plane it can carry higher current than calculated by a calculator as the heat will be taken away and spread on the plane. But that is only my theory.