Pro Micro ATmega32U4 Micro USB 8MHz/16MHz 5V/3.3V Module For Arduino Leonardo ATMega32U4 Controller Pro Micro Replace ATMega328
[ATmega32U4 Pro Micro 3.3V]
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 USB connectivity on-board and do away with bulky external USB interface.
This tiny little board does all of the neat-o for 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 8MHz and 3.3V, this board will remind you a lot of your other favorite for 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 on not VCC.
This latest revision corrects the silk error from the last version of the board so that pin 14 is correctly labeled. We've also added a PTC fuse and diode protection to the power circuit and corrected the RX and TX LED circuit.
Feature:
ATMega 32U4 running at 3.3V/8MHz
Supported under For Arduino IDE v1.0.1
On-Board micro-USB connector for programming
4 x 10-bit ADC pins
12 x Digital I/Os (5 are PWM capable)
Rx and Tx Hardware Serial Connections
Our Smallest for Arduino-Compatible Board Yet!
[ATmega32U4 Pro Micro 5V]
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 USB connectivity on-board and do away with bulky external USB interface.
This tiny little board does all of the neat-o for 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 a lot of your other favorite for 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 on not VCC.
This latest revision corrects the silk error from the last version of the board so that pin 14 is correctly labeled. We've also added a PTC fuse and diode protection to the power circuit and corrected the RX and TX LED circuit.
Dimensions: 1.3x0.7"
Feature:
ATMega 32U4 running at 5V/16MHz
Supported under for arduino IDE v1.0.1
On-Board micro-USB connector for programming
4 x 10-bit ADC pins
12 x Digital I/Os (5 are PWM capable)
Rx and Tx Hardware Serial Connections
Our Smallest for arduino -Compatible Board Yet! 
