I fried an UNO Rev 3 component!

I applied 14v to the Vin slot. Obviously, that was not a good thing :frowning:
Immediately, smoke came from the board as indicated in the attached photo.
My question is…
What is that component?
I’m hoping all will be well once I replace it :smiley:
Many thanks,

Arduino Uno booboo.jpg

AFAIK 5V regulator


That’s the 5V regulator. Did you have a lot of things connected that would draw lots of 5V current at the same time?

Yes you can replace it. You can see its part number on the schematic, something like LM1117-N-5.0 in SOT-223 package

Next time keep voltage <= 12V.

I believe MC33269 was used on older versions of the board, and would also work (same pinout).

Thanks for your responses. The only thing connected at the time was an LED with a 330 ohm resister.
I was under the impression that 12v is preferred by all Arduinos but could handle 18-20 volts. I’ll be sure to keep things <12v in the future.
Again, many thanks :slight_smile:

Read the data sheets for the regulators to see the max they can handle - usually it is for a very low current amount otherwise they drastically heat up. If you're only running some simple LEDs, then 7.5V is even better. http://www.dipmicro.com/store/DCA-07510

not a short on an output ?

because, even <= 12V is recommended (and 7 → 9 V even better), 14V shouldn’t have killed the reg.

Would have had to shorted 5V to Gnd to kill the regulator.

markobaldo, You aren't working on a metal/conductive surface are you?

@Crossroads LOL. Even I know better than to work on a metal conductive surface—though I totally understand the reason for your question. The 7.5v power supply looks good however, as full-time RVers, our main power source is the sun. The mention of RV usually brings visions of bus-type vehicles lined up in a row 6 feet apart. We, however, live in a 5th wheel trailer and are known as "boondockers"—folks who park in seclusion on public land for weeks at a time. The voltage in our rig varies from 11.9v to 14.8v—depends on where we our on our solar-charging cycle.

BTW... I noticed you are located in or around Beantown. I grew up in Milton & attended high school in Boston.

Thanks for your feedback, Markobaldo

Beantown - I am an out of state transplant ;) Hard to relate to folks reminiscing at work, not having grown up around here.