Arduino Pro Mini 3.3V ATmega328P Development Board

The Arduino Pro Mini 3.3V Development Board is a compact microcontroller board based on the ATmega328P, designed for low-power embedded applications. Running at 3.3V and 8MHz, it is ideal for battery-powered devices, wireless sensor nodes, IoT projects, and electronics that require native 3.3V logic levels. Without an onboard USB interface, the Pro Mini is perfect for permanent installations where a small footprint, low power consumption, and reliable performance are essential.

Key Specifications

• Microcontroller: ATmega328P-AU
• Operating Voltage: 3.3V
• Clock Speed: 8MHz
• Input Voltage: 3.3V to 12V via RAW pin
• USB Interface: External USB-to-Serial adapter required
• Digital I/O Pins: 14
• PWM Outputs: 6
• Analog Inputs: 8 (A0-A7)
• Flash Memory: 32KB
• SRAM: 2KB
• EEPROM: 1KB
• Maximum Regulated Output: 150mA
• Board Dimensions: 18mm × 33mm
• PCB Thickness: 0.8mm
• Weight: Less than 2g

Features

• Optimised for low-power 3.3V applications and battery-powered projects.
• Fully compatible with the Arduino IDE and existing Arduino libraries.
• ATmega328P running at 8MHz for efficient operation at 3.3V.
• Eight analogue inputs, including ADC6 and ADC7 for expanded sensor connectivity.
• Six PWM outputs for LED dimming, motor control, and servo applications.
• Onboard 3.3V voltage regulator accepts external supplies up to 12V via the RAW pin.
• Supports automatic reset when used with compatible USB-to-Serial programmers.
• Power and status LEDs simplify development and troubleshooting.
• Over-current protected design for improved reliability.

Applications

• Battery-powered electronics
• Wireless sensor networks
• IoT and smart home devices
• Bluetooth, LoRa, and 3.3V RF modules
• Environmental monitoring
• Embedded control systems
• STEM education and prototyping

Programming Notes

• The Pro Mini does not include onboard USB and requires an external USB-to-Serial programmer for uploading sketches.
• We recommend pairing it with our FTDI FT232RL USB to TTL Serial Adapter, which supports automatic reset for convenient programming.
• When using an unregulated power source, connect power to the RAW pin. For a regulated 3.3V supply, connect directly to VCC.

Resources

• ATmega328P Datasheet

Looking for a faster 5V version? Check out the Arduino Pro Mini 5V Development Board. If you need built-in USB connectivity, the Arduino Pro Micro 5V Development Board offers the same compact form factor with native USB support. You can also browse our complete Arduino collection to find the right board for your next project.

New to Arduino? Follow our Arduino Getting Started Guide to learn the basics, then build your first project using our LED Blink Tutorial.

This product can be found here:

• Arduino Compatible Boards
• Arduino Development Boards
• Boards
• Boards
• Development Boards