In my project I have stabilized 5V power supply to power Arduino Mega 2560. May I connect it to +5V pin ? Will it not damage Arduino builtin stabilizer, or will not the stabilizer take some (significant) current ?

Powering Mega 2560 with 5V

cmiyc March 9, 2012, 2:26am 2

The term you want is "regulator".

You can put regulated 5V on the pin.