Arduino Uno Rev3 SMD is based on the ATmega328. It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz clock (CSTCE16M0V53-R0), USB connection, power jack, ICSP header and reset button. It includes everything needed to support the microcontroller; simply connect it to your computer with a USB cable or power it with an AC-DC adapter or battery to get started.

The Uno differs from all previous boards in that it does not use the FTDI USB-to-serial converter.

Additional features of the R3 version are:

• ATmega16U2 instead of the 8U2 as the USB-to-serial converter.
• 1.0 pinout: added SDA and SCL pins for TWI communication placed near the AREF pin and two other new pins placed near the RESET pin, IOREF, which allows shields to adapt to the voltage supplied by the board.
• stronger RESET circuit.

Specifications

Pinout

Download the full pinout diagram as PDF here.

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