The Arduino Mega 2560 is a microcontroller board based on the ATmega2560. It has 54 digital input/output pins (of which 15 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal, USB connection, power jack, ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. The Mega is compatible with most shields designed for the Arduino Duemilanove or Diecimila.
This MEGA 2560 module is 100% Arduino compatible, using the exact same board layout and schematic. It saves more than 20 Dollar compared to the original board with the Arduino brand logo on it, but it is a legal product, and provides exactly the same reliability and performance.
Dimensions: 102 x 54 x 16mm
Operating Voltage: 5V
Logic Level: 5V
Input Voltage: 6.5-15V (limits)**
Digital I/O Pins: 54
thereof PWM: 14
Analog Input Pins: 16 (10 bit)
DC Current per I/O Pin: 40 mA (max.)
DC Current for 3.3V Pin: 50 mA (max.)
Flash Memory: 256 KB (8 KB used by bootloader)
SRAM: 8 KB
EEPROM: 4 KB
Clock Speed: 16 MHz
**The 5V LDO on the original Arduino board can stand peaks of 20V