Hi I made my own PCB board based in arduino leonardo with ATmega32U4 but I connect a digital I/O pin that I should't to VUSB and it causes my uC to heat a lot and USB port malfunction. So I want to know if there is any way to disonnect it with source code like disable the port or something, other way I will have to remove the uC from the PCB and I dont have the tools.
thanks in advance.
One would think that if the pin was set to INPUT it wouldn't bother the line, presenting just a 1uA load (i.e., next to nothing).
Yes I have try setting the pin to input and set the pull up and pull down resistors, but it seems like this pin is feeding the uC and its peripherals.
Yes, Vusb can power a uC thru an IO pin, that is not good.
Anyway you can cut the trace? That would be best.
No I can't cut it, because the connection is under the uC, it seems that the only way it's to desoldering, cut it and re-soldering
Ok. If the part is getting hot already, that's a good sign that it is damaged already. Would be best to put a new one on in it's place.
Yes is getting hot but it still working, except for the USB port that works some times, given these symptoms do yo still recommend to replace the uC?
thanks for your help.
Yes. Just a matter of time until it fails completely. Then you risk damaging the board removing & replacing a 2nd time.
What package is the uC in? If it's TQFP, with great care, good eyesight, and appropriately small cutters, you can cut the pin without removing the chip, then hit the pin with the soldering iron to pull away the remains of the pin. It's tedious, but since you're looking at replacing the uC, it's less tedious than that (unless you have a proper hot-air rework station)
do yo still recommend to replace the uC?
Please read this:
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Heat Stress
DrAzzy:
with great care, good eyesight, and appropriately small cutters, you can cut the pin without removing the chip
Actually, use a "craft" knife or No 15 scalpel.
This is a hardware problem, not software.