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： CM4 OpenWrt Tutorial Industrial Isolated USB TO 4CH RS485 (B) Converter UART CH344L For Wall/Rail-Mount Milk V 0.85inch Screen ESP32 S3 Development Board 2.41 inch AMOLED Display 600x450 TouchScreen For Arduino LVGL With SD-Port/ QMI8658C 6-Axis Sensor 2.66inch e-Paper e-link Module 360x184 4-Color Red Yellow Black White For Arduino Raspberry Pi STM32 Jetson Tutorial Information Wiki Program Code User Guide SpotPear Raspberry Pi Pico ST7789 ESP-NOW Control IO BASE MINI Board ESP32-P4-Core Board with 32MB PSRAM USB With Camera Port / Display Port Jetson Nano IO Board Raspberry Pi DSI Scr Sipeed Lichee Tang Nano 4K FPGA MINI Development Board W1NSR-LV4C GOAI Gowin ESP32 Development Board WiFi+Bluetooth Ultra Low Power Dual Core ESP 32S ESP 32 Similar ESP8266 DeepSeek AI Voice Chat ESP32-S3 Box N16R8 AUDIO Board Support External LCD/Camera AI deepseek Raspberry Pi 1.5inch LCD Spotpear ESP32-P4-WIFI6 5inch LCD Display AI Development Board 720×1280 5 inch TouchScreen Deepseek waveshare Sipeed NanoCluster Mini Cluster Board mini data center For Raspberry Pi CM45 / Computer /LM3H /M4N

Arduino Uno R3 Hardware Reference

UNO R3 Development board Case ABS UNO R3 case for Arduino