Arduino Uno - R3 (original chip)

The Arduino Uno R3 (Original Chip) is one of the most popular and beginner-friendly microcontroller boards in the Arduino family. Built around the ATmega328 microcontroller, it provides 14 digital input/output pins (6 with PWM capability) and 6 analog input pins, making it suitable for a wide variety of electronic projects.

Running at a 16 MHz clock speed with 32KB of flash memory (0.5KB used by the bootloader), the Uno R3 delivers reliable performance for programming, prototyping, and embedded system development.

The board includes a USB connection for programming, a power jack for external supply, an ICSP header, and a reset button. Simply connect it to a computer via USB or power it with an AC-to-DC adapter or battery to get started. The Uno R3 is compatible with a wide range of Arduino shields, expanding its functionality for countless applications.

Technical Specifications

Microcontroller: ATmega328

Operating Voltage: 5V

Recommended Input Voltage: 7–12V

Input Voltage (Limits): 6–20V

Digital I/O Pins: 14 (6 PWM outputs)

Analog Input Pins: 6

DC Current per I/O Pin: 40 mA

DC Current for 3.3V Pin: 50 mA

Flash Memory: 32 KB (0.5 KB used by bootloader)

SRAM: 2 KB

EEPROM: 1 KB

Clock Speed: 16 MHz

Pin out

• Digital I/O Pins: D0–D13
• PWM Pins: D3, D5, D6, D9, D10, D11
• Analog Input Pins: A0–A5
• I2C Pins: SDA (A4), SCL (A5)
• SPI Pins: SS (D10), MOSI (D11), MISO (D12), SCK (D13)
• Serial Communication: RX (D0), TX (D1)
• Power Pins: 5V, 3.3V, GND, VIN, RESET

Applications

Electronics learning and education

Robotics projects

Sensor interfacing

Home automation

LED and motor control projects

Embedded system prototyping