Arduino UNO R3 is the world’s most trusted beginner and prototyping board. Powered by the ATmega328P @ 16 MHz, it combines 14 digital I/O (6 PWM), 6 analog inputs, rock-solid 5V logic, and the broadest ecosystem of Arduino shields, sensors, and displays. If you’re teaching a class, starting a lab, or bootstrapping a product idea in the Philippines, this is the reliable, repeatable choice.

Why Makers & Classrooms Choose UNO R3

• Beginner-friendly & battle-tested: Huge community, examples, and libraries work out of the box with the Arduino IDE.
• 5V shield compatibility: R3 footprint and pinout mean instant add-ons for motor control, Ethernet, LCDs, and more.
• Stable USB & power: Program via USB-B; power from USB or DC jack (recommended 7–12 V) for standalone projects.
• Perfect for teaching: Simple toolchain, reliable hardware, and endless tutorials for fast classroom wins.

What You Can Build

• STEM projects: traffic lights, temperature loggers, distance meters, datalogging with RTC + microSD
• Home & hobby: smart plant watering (relay + soil sensor), door alarms (PIR), IR remotes
• Robotics: line followers and 2WD cars with motor shields and IMU/ToF sensors

Starter Bundles (Quick Picks)

• UNO Learning Kit: UNO R3 + USB-B cable + breadboard & jumpers + basic sensors + 0.96″ OLED
• Sensor Lab: UNO R3 + BME280 + HC-SR04 + relay + data logging shield
• Robot Starter: UNO R3 + 2WD chassis + L293D/TB6612 shield + battery/PSU

Recommended Add-Ons

• USB-B cable for programming and power
• Sensor packs (DHT22, PIR, HC-SR04, IMU, light)
• Displays (1602 LCD, OLED, TFT)
• Arduino shields (motor, relay, Ethernet, proto)
• 5V/9V/12V power supplies & 5.5×2.1 mm barrel adapters
• Tools (soldering, tweezers) & multimeter for troubleshooting
• Cases & mounting (clear acrylic, ABS, DIN-rail)

Technical Specifications

Pinout & Power Tips

• SPI via ICSP: Use the 6-pin ICSP header for reliable SPI (works on UNO/Mega alike).
• Level safety: UNO is 5 V. If a module is 3.3 V-only, add a logic level converter.
• Power sources: For portable builds, power via DC jack or VIN (7–12 V recommended). For bench work, USB is fine.

Learning Path (Beginner → Intermediate)

1. Blink & Inputs: LED blink, button debounce, tone/buzzer
2. Sensing: DHT22 temp/humidity, HC-SR04 distance, LDR light
3. Outputs: relays, servos, LCD/OLED
4. Data logging: microSD + RTC shield, graphs & alerts
5. Motion & robots: motor shield + 2WD/4WD chassis + IMU

What’s in the Box

• Official Arduino UNO R3 board

Compatibility & Notes

• Shields: R3 footprint with full 5 V logic for maximum shield compatibility.
• Drivers: Official boards use ATmega16U2 and usually don’t need extra drivers; some compatibles use CH340/CP2102 (install if required).
• UNO R3 vs R4: R4 is 32-bit with USB-C but keeps R3 shield compatibility. If you need native 5 V + classic ecosystem, UNO R3 remains a solid default.