A000066 Arduino, A000066 Datasheet - Page 2

• Manufacturer Part Number: A000066
• Description: Development Boards & Kits - AVR ARDUINO UNO REV 3
• Manufacturer: Arduino

Specifications of A000066

• Rohs: yes
• Product: Development Kits
• Tool Is For Evaluation Of: ATmega328P
• Core: AVR8
• Interface Type: I2C, ICSP, SPI, USB
• Data Bus Width: 8 bit
• For Use With: ATmega

Summary
Schematic & Reference Design
EAGLE files:
Schematic:
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.
Power
The Arduino Uno can be powered via the USB connection or with an external power supply. The power source is selected
automatically.
External (non-USB) power can come either from an AC-to-DC adapter (wall-wart) or battery. The adapter can be connected by
plugging a 2.1mm center-positive plug into the board's power jack. Leads from a battery can be inserted in the Gnd and Vin pin
headers of the POWER connector.
The board can operate on an external supply of 6 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less
than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board.
The recommended range is 7 to 12 volts.
The power pins are as follows:
Memory
The ATmega328 has 32 KB (with 0.5 KB used for the bootloader). It also has 2 KB of SRAM and 1 KB of EEPROM (which can be read
and written with the
Input and Output
Each of the 14 digital pins on the Uno can be used as an input or output, using pinMode(), digitalWrite(), and
functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor
(disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions:
Microcontroller
Operating Voltage
Input Voltage (recommended) 7-12V
Input Voltage (limits)
Digital I/O Pins
Analog Input Pins
DC Current per I/O Pin
DC Current for 3.3V Pin
Flash Memory
SRAM
EEPROM
Clock Speed
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). You can supply voltage through this pin, or, if supplying voltage via the power
jack, access it through this pin.
5V. The regulated power supply used to power the microcontroller and other components on the board. This can come either
from VIN via an on-board regulator, or be supplied by USB or another regulated 5V supply.
3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA.
GND. Ground pins.
Serial: 0 (RX) and 1 (TX). Used to receive (RX) and transmit (TX) TTL serial data. These pins are connected to the
corresponding pins of the ATmega8U2 USB-to-TTL Serial chip.
arduino-uno-Rev3-schematic.pdf
arduino-uno-Rev3-reference-design.zip
EEPROM
library).
ATmega328
5V
6-20V
14 (of which 6 provide PWM output)
6
40 mA
50 mA
32 KB (ATmega328) of which 0.5 KB used by bootloader
2 KB (ATmega328)
1 KB (ATmega328)
16 MHz
digitalRead()