It's like a shrunken version of the Arduino Leonardo as it features the same ATmega32U4 microcontroller, micro-USB port, and pinouts. It also operates at 5V and requires an external supply of 7 to ...

One Leonard-Micro difference is with the ‘built-in’ led. In the Leonardo, an op-amp between the ATmega pin and the led means that loading is minimal and the pin can easily be used as an Arduino input.