The Arduino Uno R3 is a microcontroller board with ATmega328, 14 digital I/O, 6 analog inputs, 16MHz ceramic resonator, 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 an USB cable or power it using an AC-to-DC adapter or battery to get started.

The Arduino Uno R3 differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega16U2 programmed as a USB-to-serial converter.

Revision 3 has the following new features:

• 1.0 pinout: added SDA and SCL pins that are near to the AREF pin and two other new pins placed near the RESET pin. One is the IOREF that allow the shields to adapt to the voltage provided from the board. The other is a not connected and is reserved for future purposes. The Uno R3 works with all existing shields but can adapt to new shields which use the addition pins. 
• Stronger RESET circuit
• Atmega 16U2 replaces the 8U2.

Arduino Uno Features:

• ATmega328 microcontroller
• Operating voltage 5V
• Input voltage 7-12V (6-20V limits)
• 14 x digital I/O pins (6 provide PWM output)
• 6 x analog input pins
• DC current per I/O pin 40mA
• DC current for 3,3V pin 50mA
• Flash memory 32kb
• Clock speed 16MHz
• Added SDA and SCL pins
• USB overcurrent protection
• Automatic (Software) reset
• Dimension: 68,58 x 53,34mm

Note: The price includes the board only. To run this product properly you also need a power supply and a USB cable. Please check accessories for suitable parts.