1. Product Description

The Arduino Pro Mini 3.3V / 8MHz Development Board is a compact and low-power microcontroller board based on the ATmega328P-AU microcontroller, designed for embedded electronics, robotics, automation, and portable electronic applications. Its small form factor makes it suitable for projects where space efficiency and low power consumption are important.

Operating at 3.3V with an 8MHz clock frequency, the Arduino Pro Mini is designed for applications requiring lower operating voltage and reduced power consumption compared to standard 5V Arduino boards. It provides 14 digital input/output pins, 8 analog input channels, and 6 PWM-capable outputs for interfacing with various electronic components and sensors.

The board features a TTL-level UART serial interface through RX and TX pins, allowing communication with computers and other microcontrollers using a compatible USB-to-TTL serial adapter. It supports serial programming and can be programmed using the Arduino IDE.

The Arduino Pro Mini supports an external DC power supply through its RAW and GND pins, with an input voltage range of approximately 3.5V to 12V as specified for this board. It can also be powered using a compatible 9V battery, making it suitable for battery-operated and portable projects.

Based on the ATmega328P-AU microcontroller, the board offers reliable processing capabilities and compatibility with a wide range of Arduino libraries and electronic modules. Its compact dimensions of approximately 33.3 × 18.0 mm allow easy integration into custom PCBs, enclosures, and embedded systems.

With its small size, 3.3V operation, low-power design, and flexible interfacing capabilities, the Arduino Pro Mini is an excellent choice for wireless sensor nodes, IoT devices, wearable electronics, robotics, and educational electronics projects.

2. Key Features

• ATmega328P-AU Microcontroller: Provides reliable processing for embedded applications.

• 3.3V Operating Voltage: Suitable for low-voltage electronic circuits and compatible sensors.

• 8MHz Clock Frequency: Provides stable processing for low-power applications.

• Compact Design: Small dimensions of approximately 33.3 × 18.0 mm for space-constrained projects.

• 14 Digital I/O Pins: Supports digital input and output operations.

• 8 Analog Input Channels: Allows interfacing with analog sensors and measurement circuits.

• 6 PWM Outputs: Supports PWM-based control of LEDs, motors, and other devices.

• TTL Serial Communication: Provides RX and TX pins for UART communication.

• Serial Programming Support: Can be programmed using an external USB-to-TTL serial adapter.

• External Power Supply: Supports approximately 3.5V to 12V DC input through RAW and GND.

• Battery Operation: Can be powered using a compatible 9V battery.

• Arduino IDE Compatibility: Supports programming through the Arduino development environment.

• Low-Power Operation: Suitable for portable and battery-powered electronic systems.

• Easy Integration: Can be incorporated into custom electronic circuits and embedded projects.

3. Technical Specifications

4. Design and Construction

The Arduino Pro Mini features a compact and lightweight PCB design built around the ATmega328P-AU microcontroller. Its small dimensions make it suitable for installation in compact electronic devices, portable systems, and custom circuit boards.

The board provides clearly arranged digital and analog pins for connecting sensors, switches, LEDs, displays, and other electronic components. It also includes dedicated RX and TX pins for serial communication and programming.

Unlike development boards with built-in USB connectors, the Arduino Pro Mini requires an external USB-to-TTL serial adapter for programming. This design reduces board size and makes it suitable for permanent embedded installations.

The RAW and GND pins provide external power input, while the regulated 3.3V output can supply compatible low-voltage components within the board’s power limitations.

5. Working Principle

The Arduino Pro Mini operates using the ATmega328P-AU microcontroller, which executes the program uploaded through a compatible USB-to-TTL serial adapter.

Once powered, the microcontroller reads input signals from connected digital and analog devices. It processes the received information according to the programmed instructions and generates appropriate output signals.

The digital I/O pins can control LEDs, relays, switches, and other digital devices. The analog input channels read varying voltage signals from compatible sensors, while the PWM pins provide variable-duty-cycle output for controlling LED brightness and motor speed through suitable driver circuits.

The UART serial interface enables communication with other microcontrollers, computers, and serial modules. The board operates at 3.3V and an 8MHz clock frequency, making it suitable for low-power embedded applications.

6. Applications

• IoT Projects: Used in compact Internet of Things devices and sensor nodes.

• Wireless Sensor Networks: Suitable for collecting and transmitting sensor information.

• Robotics: Controls sensors, actuators, and motor driver circuits.

• Home Automation: Supports automated lighting and electronic control systems.

• Wearable Electronics: Its compact size makes it suitable for wearable devices.

• Battery-Powered Projects: Ideal for portable electronics requiring low-power operation.

• Environmental Monitoring: Interfaces with temperature, humidity, and environmental sensors.

• Data Logging: Collects sensor readings for storage and monitoring.

• Remote Monitoring: Can be integrated with wireless communication modules.

• Educational Projects: Helps students learn microcontroller programming and electronics.

• Embedded Systems: Suitable for custom electronic circuits and compact control applications.

• LED and Motor Control: Uses PWM outputs for controlling compatible external driver circuits.

7. Package Includes

– 1 × Arduino Pro Mini 3.3V / 8MHz Development Board

8. Disclaimer

The images shown are for representation purposes only. The actual product may differ slightly in colour, appearance, component placement, or PCB layout.

This board does not have a built-in USB programming connector. An external USB-to-TTL serial adapter is required for programming. Ensure that the adapter uses compatible 3.3V logic levels.

The RAW input voltage range and power supply requirements should be checked before connecting external components. Avoid applying 5V signals directly to the 3.3V logic pins.