I have blown up 2 Arduino Nanos and I'm trying to figure out what I'm doing wrong.

In both cases, I was powering the boards with a 16V supply (I know this is high, but the regulator datasheet says it is good to 25V, and the regulator was not damaged). I unplug the supply and USB cable and then start soldering to one of the pins (A6). When I plug the board back in, the L LED does not flash, indicating the bootloader has been erased. The POW light is on and I still measure 5V, indicating the regulator is working. When I connect the board to my PC, the serial port pops up just fine. But when I try to upload a sketch, the IDE times out and says it cannot communicate with the board.

I attempted to reprogram the bootloader using a raspberry pi but avrdude also says it cannot find the device either. It looks like the microcontroller is blown.

My iron tip is grounded, so my best guess is some residual power in the supply travels through the microcontroller to my iron and shorts something out. But this seems unlikely seeing as A6 is an input and grounding it should be just fine even when the supply is fully on.

Any ideas what I could be doing wrong? FYI, I am cross-posting this on the Arduino forums.

  • What circuit are you soldering the Nanos to and are you using the Vin pin correctly? Have you tested this configuration on a breadboard? Cross-posting to what other StackExchange sites?
    – StarCat
    Apr 26, 2020 at 6:20
  • forum.arduino.cc/index.php?topic=680237
    – Juraj
    Apr 26, 2020 at 8:50
  • 1
    If your nano is a cheap chinese clone then it could die just by you looking at it wrong.
    – Majenko
    Apr 26, 2020 at 9:33
  • Check your soldering temperature and that you are not overheating the microcontroller, or any other component on the board. Also check your flux. Some types are more conductive than others and you will need to take care cleaning with isopropanol.
    – MichaelT
    Apr 26, 2020 at 12:14
  • Thanks. The configuration works fine until the soldering event. Yes, it's a clone; maybe that is the issue. I am not overheating the microcontroller; the point where I'm soldering is pretty far from it. I am cleaning the flux.
    – justinis
    Apr 26, 2020 at 15:03

1 Answer 1


My advice would be not to solder directly to the Nano pins. Instead, use the appropriately sized DIL socket, and solder to the pins of that instead. Then plug in the Nano once the soldering is complete.

  • the OP would probably have to solder the headers to the board first
    – jsotola
    Apr 26, 2020 at 18:13

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.