Arduino Uno R3 Hardware Reference

In the Arduino development board family, the Uno development board is the most beginner-friendly Arduino development board. Because it is easy to learn, stable and reliable, the Uno development board is also the most widely used development board with the most reference materials.

Arduino Uno is a development board based on microcontroller ATmega328P. It has 14 digital input/output pins (6 of these pins can be used as PWM output pins), 6 analog input pins, 16 MHz quartz crystal oscillator, USB interface, power interface, supports in-circuit serial Programming and reset buttons. Users only need to connect the development board to the computer through the USB interface to use it.

If you choose the Arduino clone board, you can learn how to install the driver for the Arduino clone board through our tutorial.

The main technical parameters

Microcontroller: ATmega328P

Working voltage: 5 volts

Input voltage (recommended) : 7-12 volts

Input voltage (limit) : 6-20 volts

Digital input and output pins: 14 (6 of which can be used as PWM pins)

PWM pins: 6

Analog input pins: 6

Input/Output Pin DC Current : 20mA

3.3V pin current: 50 mA

Flash Memory (flash memory): 32 KB (ATmega328P) of which 0.5 KB is used for system boot (bootloader)

SRAM (static memory): 2 KB (ATmega328P)

EEPROM: 1KB (ATmega328P)

Built-in LED pins: 13

Length: 68.6mm

Width: 53.4mm

Weight : 25g

Clock frequency: 16MHz

Pin Description Diagram

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Arduino Uno R3 Hardware Reference

UNO R3 Development board Case ABS UNO R3 case for Arduino