Arduino Mega 2560 heatup with 9V DC power supply

Hello I'm totally new to this forum and this is my first topic. hoping I'm posting in a right way.

I recently bought a Arduino Mega 2560 and according to it's documents, a 9V power supply would be great for it. I just finished the programing and now I want to test it on external power but whenever I connect it to the 9V 2A power supply, the atmega 2560 become very hot that I can't touch it. The code also take a bit time to start. I don't have this issue with usb power and everything is fine. I just wanted to know is it a normal behavior or I did something wrong? By the way, I want to run it on external power for more than 20 days. so heatting is important and I don't want to fry up my arduino.

is the arduino a genuine or a off-brand?

creatingaccountjusttoaskaquestio: is the arduino a genuine or a off-brand?

I'm not sure but it should be genuine

To which pins did you connect the power supply?

sterretje: To which pins did you connect the power supply?

I connect power supply to DC input jack

Connecting to the barrel is fine. It should not heat up the microcontroller.

So you’ll have to look for other causes.

First thing that I would do is test without anything connected to the board except for the power supply.

Second check that I would do is to check the output of the 5V regulator (on the 5V pin); that feeds the whole board with 5V and if faulty can provide 9V to the board.

sterretje: Connecting to the barrel is fine. It should not heat up the microcontroller.

So you'll have to look for other causes.

First thing that I would do is test without anything connected to the board except for the power supply.

Second check that I would do is to check the output of the 5V regulator (on the 5V pin); that feeds the whole board with 5V and if faulty can provide 9V to the board.

I've tested it without anything connected to the board. the same issue again. Unfortunately i don't have multimeter to measure the output of the 5V regulator. Isn't there anything else that i can do?

I’m out of options. Sorry.

does the board say arduino on it?