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： ESP32 CAN FD XIAO RA4M1 Tiny SuperMini Board For Arduino Uno IDE For SeeedStudio R7FA4M1 Jetson Orin Nano/NX Super Developer IO Base Development Board Dual network RJ45 For Jetson Orin Nano/NX Module Finger Vein Scanner Module (A) Cortex M4F UART 3.3V TTL UL94-5VB IP56 Better Than Fingerprint Recognition Raspberry Pi IR Thermal Imagi ESP32 S3 AI 1.85 inch Development Board with 1.85inch LCD Touchscreen Round Screen Electronic Badge Deepseek ESP32-S3 Relay 6-Channel IOT WiFi Bluetooth RS485 Pico Protection Circuits USB Camera 5MP OS05A20 USB 2.0 onboard single mike 175° wide angle Mini TOF Time-of-Flight Laser Ranging Radar Sensor Compatible RS485 with Arduino Raspberry Pi ESP32 and Pico ESP32 C3 Voice Robot Mini Development Board AI DeepSeek Toy Doll Core 1.28 inch 1.54inch LCD ESP32 LVGL 0.85inch Display Raspberry Pi 1.54inch OLED Raspberry Pi LCD Raspberry Pi PCF8591 expansion board LED GPIO IO test ADC/DCA Sensor Beginner board ESP32 IR Thermal Imaging Camera ESP32-C6 LCD Development Board 1.3 inch Display 1.3inch Screen ST7789 240x240 Mini TV SD-Port QST LVGL For Arduino Sipeed NanoCluster Mini Cluster Board mini data center For Raspberry Pi CM45 / Computer /LM3H /M4N Lichee-Tang-Primer-20K-FPGA-Unboxing

Arduino Uno R3 Hardware Reference

UNO R3 Development board Case ABS UNO R3 case for Arduino