ARDUINO UNO REV3 SMD is a microcontroller board based on ATmega328. It has 14 digital input/output pins (6 of which can be used as PWM outputs), 6 analog inputs, a 16 MHz ceramic resonator (CSTCE16M0V53-R0), a USB connection, a power jack, an ICSP header, and a reset button. It contains everything you need to support the microcontroller; simply plug it into a computer with a USB cable or power it with an AC/DC adapter or battery to get started.
Arduino Uno differs from all previous boards in that it does not use the FTDI USB-to-serial driver chip.
The additional features provided with the R3 version are:
ATmega16U2 instead 8U2 as USB to serial converter.
Pin out 1.0: added SDA and SCL pins for TWI communication placed close to AREF pin and two new pins placed close to RESET pin, the IOREF that allow the displays to adapt to the voltage provided by the board and the second one is an unconnected pin, reserved for future use.
More powerful RESET circuitry.
If you are interested in boards with similar functionality, on Arduino you can find:
Arduino Uno Rev3
Arduino Uno WiFi Rev2
