Mega-2560 Key Features
- VIN. The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB
- 5V. The regulated power supply used to power the microcontroller and other ponents on the board. This can e either from
- 3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA
- GND. Ground pins