Arduino UNO R3 Original
The Arduino Uno R3 is a microcontroller board based on the ATmega328P chip.
This board has 14 digital I/O pins (6 support PWM), 6 analog inputs, a 16 MHz crystal resonator, a USB connector, a power jack, an ICSP header, and a reset button. You may quickly charge it with a USB cable, adapter, or battery.
The Uno R3 is designed for both students and enthusiasts and makes electronics and coding accessible without requiring extensive technical knowledge.
This Arduino UNO microcontroller board can be programmed using the Arduino IDE, which allows users to build sketches (code) that control the board. Even if something goes wrong, simply change the chip and restart.
"Uno" means "one" in Italian, and it marks the release of the Arduino IDE 1.0. It became the standard and reference model for subsequent Arduino boards.
Common uses of the Arduino Uno board include home automation, industrial control, and DIY electronics projects.
It can also interface with other Arduino boards or Raspberry Pi, making it a flexible choice for creators and students.
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Key Features
- ATmega328P microcontroller ensures reliable and efficient performance
- Includes 14 digital input/output pins, with 6 supporting PWM output
- Features 6 analog input pins for reading sensor or variable data
- Equipped with a 16 MHz ceramic resonator for stable timing
- Offers 32 KB flash memory (0.5 KB used by bootloader), 2 KB SRAM, and 1 KB EEPROM
- Can be powered via USB, DC adapter (7–12V recommended), or battery
- Integrated USB-to-serial communication using ATmega16U2 for easy programming
- Built-in resettable polyfuse provides protection against USB overcurrent
- Supports automatic reset for quick and easy code uploads
- Includes an onboard LED on digital pin 13 for basic testing
- Supports serial (UART), SPI, and I2C communication protocols
- Compatible with a wide range of Arduino shields for project expansion
- Easy to use, making it perfect for beginners and DIY electronics enthusiasts
Arduino UNO Pin Diagram
The power pins are as follows:
Pin |
Description |
Vin |
The input voltage to the Arduino board when using an external power source (7–12V). You can supply voltage through this pin, or access it if supplying voltage via the DC power jack. |
5V |
Outputs a regulated 5V from the onboard regulator. Power can come from the USB, DC jack, or Vin pin. Do not supply power to this pin directly, as it bypasses the regulator. |
3.3V |
Outputs 3.3 volts generated by the onboard regulator. Maximum current draw is 50 mA. |
GND |
Ground pins used to complete the circuit. Multiple GND pins are available. |
IOREF |
Provides the voltage reference at which the microcontroller operates. Shields can use this pin to adapt to the board’s voltage (5V or 3.3V). |
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Arduino Nano vs Uno Comparison Table
Feature
|
Arduino UNO R3 (Original)
|
Arduino Nano (Original)
|
Price (Robocraze) |
?1,860 |
?1,798 VIEW
|
Microcontroller |
ATmega328P |
ATmega328P |
Operating Voltage |
5V |
5V |
Input Voltage |
7-12V |
7-12V |
Digital I/O Pins |
14 (6 PWM) |
14 (6 PWM) |
Analog Input Pins |
6 |
8 |
Clock Speed |
16 MHz |
16 MHz |
Flash Memory |
32 KB (0.5 KB used by bootloader) |
32 KB (0.5 KB used by bootloader) |
SRAM |
2 KB |
2 KB |
EEPROM |
1 KB |
1 KB |
USB Interface |
Standard USB Type-B |
Mini USB |
Size |
Larger (approx. 68.6mm x 53.4mm) |
Compact (approx. 45mm x 18mm) |
Best for |
Beginners, shields, projects needing standard size |
Compact projects, breadboard-friendly applications |
Wireless Capability |
Needs external module (e.g., ESP8266, HC-05) |
Needs external module (e.g., ESP8266, HC-05) |
Expandable with Shields |
Yes, compatible with multiple shields |
Limited due to size constraints |