Arduino Mega

The Arduino Mega 2560 is a microcontroller board based on the ATmega2560. It has 54 digital input/output pins (of which 14 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB connection, a power jack, an 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.

Feature 
Microcontroller                            ATmega2560
Operating Voltage                        5V
Input Voltage (recommended)       7-12V
Input Voltage (limits)                   6-20V
Digital I/O Pins                            54 (of which 14 provide PWM output)
Analog Input Pins                        16
DC Current per I/O Pin                 40 mA
DC Current for 3.3V Pin                50 mA
Flash Memory                             256 KB of which 8 KB used by bootloader
SRAM                                        8 KB
EEPROM                                     4 KB
Clock Speed                                16 MHz

Download Schematic here:

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