SPECIFICATIONS

Pro Micro ATmega32U4 Official Version 5V/16M Microcontroller Development Board
The Pro Micro is similar to the Pro Mini, but comes with a built-in ATmega32U4. The internal USB transceiver of the 32U4 allows USB connectivity to be integrated directly on the board, eliminating the need for bulky external USB interfaces.
This compact board features all the familiar Arduino capabilities: 4 channels of 10-bit ADC, 5 PWM pins, 12 digital I/O pins, and hardware serial connections for Rx and Tx. Operating at 16MHz and 5V, it will remind you of many other popular Arduino-compatible boards—but this little board can go anywhere. It includes an onboard voltage regulator, allowing it to accept input voltages up to 12VDC. If powering the board with an unregulated supply, be sure to connect to the "RAW" pin instead of VCC.
This latest version corrects a silkscreen error from previous revisions to properly label Pin 14. We have also added PTC fuse and diode protection to the circuit and improved the RX and TX LED circuitry.
Features:

• ATmega32U4 running at 5V/16MHz

• Supported under Arduino IDE v1.0.1 and later

• Onboard micro USB port for programming

• 4 × 10-bit ADC pins

• 12 digital I/O pins (5 supporting PWM)

• Rx and Tx hardware serial connections

• Our smallest Arduino-compatible board