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.