My Arduino Uno R4 Minima started smoking after connecting to a computer. I disconnected it and visually checked it and I saw this bubble as shown on this photo.

Photo of my Uno R4

Can I recover my Uno from this to still use it or do I have to throw it away?

  • 1
    Was anything else connected?
    – KIIV
    Commented Mar 31 at 10:09
  • Can the computer still talk to the board? If not, then it's probably dead. You could repair it by replacing the IC, if you are handy with a hot air gun. If not, I still wouldn't throw it away, it might be useful for parts. Commented Mar 31 at 10:38
  • did you place the board on top of something metallic?
    – jsotola
    Commented Mar 31 at 17:31
  • 1
    did you power the board with an external power supply connected to the barrel jack?
    – jsotola
    Commented Mar 31 at 17:54
  • That buck converter ISL854102 appears well protected against abuse and tolerates back feeding so it is difficult to imagine what happened here and what else may have been damaged by this incident. Datasheet: renesas.com/us/en/products/power-power-management/… .
    – 6v6gt
    Commented Apr 6 at 3:13

2 Answers 2


The marked IC is burnt. You should complain to the seller and claim warranty. if it is still within the warranty period. If you are very skilled at soldering. You can try to replace the IC.

  • 4
    If the OP damaged it through misuse then why would the seller be liable? Commented Mar 31 at 18:09

That's the buck-converter that connects to the external power supply.

The board should still work when powered by the USB cable.

Remove R11 to isolate the blown circuit if you like.


enter image description here

  • This should be the accepted answer, IMHO. Commented Apr 1 at 6:52
  • It smokes powered by USB.
    – szachy-a
    Commented Apr 1 at 10:17

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