VIN. The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source).If using more than 12V, the voltage regulator may overheat and damage the board. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may be unstable. The board can operate on an external supply of 6 to 20 volts. Leads from a battery can be inserted in the Gnd and Vin pin headers of the POWER connector.

The adapter can be connected by plugging a 2.1mm center-positive plug into the board's power jack. The power source is selected automatically.Įxternal (non-USB) power can come either from an AC-to-DC adapter (wall-wart) or battery. The Arduino Uno can be powered via the USB connection or with an external power supply. The pin configuration is identical on all three processors. 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. Schematic: arduino-uno-Rev3-schematic.pdf The Uno is the latest in a series of USB Arduino boards, and the reference model for the Arduino platform for a comparison with previous versions, see the index of Arduino boards.ģ2 KB ( ATmega328) of which 0.5 KB used by bootloaderĮAGLE files: arduino-uno-Rev3-reference-design.zip (NOTE: works with Eagle 6.0 and newer)

The Uno and version 1.0 will be the reference versions of Arduino, moving forward. 'Uno' means one in Italian and is named to mark the upcoming release of Arduino 1.0. The second one is a not connected pin, that is reserved for future purposes. In future, shields will be compatible with both the board that uses the AVR, which operates with 5V and with the Arduino Due that operates with 3.3V. 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.Revision 3 of the board has the following new features: Revision 2 of the Uno board has a resistor pulling the 8U2 HWB line to ground, making it easier to put into DFU mode.

Instead, it features the Atmega16U2 ( Atmega8U2 up to version R2) programmed as a USB-to-serial converter. The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. 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. It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz ceramic resonator, a USB connection, a power jack, an ICSP header, and a reset button. The Arduino Uno is a microcontroller board based on the ATmega328 ( datasheet).

Arduino uno r2 datasheet