The Pro Micro is similar to the Pro Mini except with an ATmega32U4 on board. The USB transceiver inside the 32U4 allows us to add native USB connectivity and do away with the bulky external USB interface.

This tiny board does all of the neat Arduino tricks that you're familiar with: 4 channels of 10-bit ADC, 5 PWM pins, 12 DIOs as well as hardware serial connections Rx and Tx. Running at 16MHz and 5V, this board will remind you of many of your favorite Arduino-compatible boards, but this little guy can go just about anywhere. There is a voltage regulator on board, so it can accept voltage up to 12VDC. If you're supplying unregulated power to the board, be sure to connect to the "RAW" pin and not VCC.

This latest revision corrects the silk error from the last version of the board so that pin 14 is properly labeled. We also added a PTC fuse and diode protection to the power circuit and corrected the RX and TX LED circuit.