This is a miniaturized version of the Pro, so it's small enough to conceal in other projects. The Pro Mini is as small as it gets. Built on the 'open-source electronics prototyping platform', and compatible with existing Arduino software libraries.

HIGHLIGHTS

• 8-bit AVR RISC-based microcontroller running at 16 MHz
• Extremely small profile – less than 1/5 the size of the OSEPP Pro board

This board is based on the Arduino Pro Mini designed by SparkFun Electronics, and is released under the Creative Commons Attribution Share-Alike License.

The original design can be found at: http://arduino.cc/en/Main/ArduinoBoardProMini

Features:

• Microcontroller: ATmega328P
• Clock Speed: 16 MHz
• Flash memory: 32 KB
• SRAM: 2 KB
• EEPROM: 1 KB
• Operating voltage: 5V
• Input voltage: 5-12V
• Digital I/O pins: 14 (including 6 for PWM)
• Analog input pins: 6
• Other connections: serial communication (requires header), power (requires header)
• Dimensions: 34 x 18 x 2mm
• Power source: external DC supply