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-S3 Development Board 1.47 inch LCD Screen Display 172x320 SD-Port LVGL USB Raspberry Pi CM5 IO BASE A Mini Board a Base Development Platform Compute Module 5 IO Board Milk-V Duo S Extend Partition on SD Card or eMMC PoE Power Supply Raspberry Pi 5 Audio Card Raspberry Pi Pico 2 RP2350A PoE ETH Ethernet Module W6300 RS232 to RJ45 Raspberry Pi Game ESP32-P4 Core Board 32MB PSRAM 16MB Flash Raspberry Pi Raspberry Pi PCM5122 I2S DAC HIFI Sound Card DAC Audio expansion Board Free-Driver For PI5/PI4/Zero Raspberry Pi 5 Sound Card X1009 Raspberry Pi 5 PCIe To 5-Port SATA SATA3.0 (NOT BOOT From SATA) DeepSeek AI Voice Chat ESP32 C6 Development Board 2.06-inch AMOLED Display 410×502 2.06inch TouchScreen Programmable Watch Raspberry Pi Pico 2 RP2350A 1.54inch TouchScreen 1.54 inch LCD Display Development Board 240×240 Serial UART Bus Servo CF35-12 TTL 35KG.CM Magnetic-Encoder High precision and Large torque Rasberry Pi 5 PCIe TO MiniPCIe 4G Gigabit Ethernet RJ45 USB HUB HAT+ SIM7600G-H/EG25-G spotpear Raspberry Pi Pico 2 RP2350 ETH CH9120 TCP/UDP Ethernet Network For Arduino Pi5 Active Cooler

Arduino Uno R3 Hardware Reference

UNO R3 Development board Case ABS UNO R3 case for Arduino