Vin pin somehow fried my arduino uno board

Please help I fried somehow my arduino uno board by applying 5v to the Vin pin. It happened two times with two different boards.

Please tell me what am I doing wrong so it won’t happen again.


You made a wrong connection.

Need more info.
Official Uno or clone (post link).
What was the 5volt power source.
Was it connected to USB at the same time.
Why 5volt on V-in. The datasheet states a minimum of 7volt on V-in.
Why didn’t you use the DC socket. It has additional polarity protection.
What else was connected to the Uno.

What did you have the negative or gnd of the 5V supply connected to?
What was your 5V supply?
If it is a wall/plug pack are you sure it is DC?

Thanks.. Tom... :slight_smile: