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

TAG： LuckFox Pico max Luckfox Pico Camera MIS5001 5MP wide-angle lenses‌ For RV1106/Pro/MAX/Ultra (Not For RV1103 Pico) Raspberry Pi Pico 2 RP2350 1.47 inch LCD Display Development board RP2350A 1.47inch Screen RGB color $8.5 4.26inch-e-Paper UNO Minima RA4M1 ZERO Tiny SuperMini R7FA4M1 Board Compatible With R4 For Arduino Programmable Keyboard SpotPear spotpear UGV Rover ROS2 PT AI OpenCV Robot Car MediaPipe For Jetson Orin Nano Raspberry Pi 4B/5 Industrial UART 2CH RS485 RS232 CAN FD HAT With Case For Installation of guide rails and hanging USB to SPI EyeLink-RC-S1 Industrial Edition 5.5 inch Touchscreen Camera R1M Card Recording Flight Controller FPV Drone ground station image transmission remote 0.85inch LCD Button Mechanical Keyboard Display Screen 128x128 For Arduino /Raspberry Pi /ESP32 /RP2040 /STM32 Jetson Nano 3G module Jetson Nano Case ESP32-S3 Smart 86 Box Development Board with 4 inch 480x480 Display Touch Screen For AI and DeepSeek LuckFox Pico User Guide Raspberry Pi Pico Basics User Guide Raspberry Pi 5 Speaker Template: Pico-get-start

Arduino Uno R3 Hardware Reference

UNO R3 Development board Case ABS UNO R3 case for Arduino