Arduino Uno R2, SMD Edition (Revision 2)
| Jameco Part no. 2151232 | |
|---|---|
| Manufacturer | ARDUINO |
| Manufacturer no. | A000049 |
| RoHS compliant | |
| Catalog 132 , page 161 | |
- Data Sheet (current) [319 KB ]
Arduino Uno R2, SMD Edition

The Arduino Uno is a microcontroller board based on the ATmega328 (datasheet). It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, 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.
The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega16U2 (Atmega8U2 up to version R2) programmed as a USB-to-serial converter.
Revision 2 of the Uno board has a resistor pulling the 8U2 HWB line to ground, making it easier to put into DFU mode.
Revision 3 of the board 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 to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board. In future, shields will be compatible both with the board that use the AVR, which operate with 5V and with the Arduino Due that operate with 3.3V. The second one is a not connected pin, that is reserved for future purposes.
- Stronger RESET circuit.
- Atmega 16U2 replace the 8U2.
The Arduino Uno R3 (DIP edition) is also available!
Summary
- Microcontroller: ATmega328
- Operating Voltage: 5 Volts
- Input Voltage (recommended): 7-12Volts
- Input Voltage (limits): 6-20Volts
- Digital I/O Pins: 14 (of which 6 provide PWM output)
- Analog Input Pins: 6
- DC Current per I/O Pon: 40 mA
- DC Current for 3.3V Pin: 50 mA
- Flash Memory: 32 KB (Atmega328) of which 0.5 KB is used by the bootloader)
- SRAM: 2 KB (ATmega328)
- EEPROM: 1 KB (ATmega328)
- Clock Speed: 16 MHz
Schematic & Reference Design
EAGLE files: arduino-uno-Rev3-reference-design.zipSchematic: arduino-uno-Rev3-schematic.pdf
Note: The Arduino reference design can use an Atmega8, 168, or 328, Current models use an ATmega328, but an Atmega8 is shown in the schematic for reference. The pin configuration is identical on all three processors.
Resources & Downloads
Arduino Documentary: Open Source Hardware is HereReport a problem
Suggest a product
No specifications are available at this time. Call for more information.
Report a problem
Suggest a product
Report a problem
Suggest a product





