How would you use an external voltage regulator for an Arduino? I've got a 5v switching regulator, but can't figure out how to wire it into the Arduino circuit. I have tested it on a separate ATMega328 board that takes 5v in, but I can't removed the 7805 regulator from the Arduino board. Is there anything bad that could happen if I just wired the switching regulator in parallel? As in, switching regulator 5v out -> Arduino 5v out pin, GND -> GND, Vin -> battery?