Adafruit Feather 32u4 Basic Proto

The Feather 32u4 Basic Proto combines an ATmega32u4, built-in USB, LiPo charging, and onboard prototyping space in a lightweight, Arduino-compatible development board ready for portable projects.

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Feather is Adafruit’s lightweight, portable development board platform, designed as a flexible standard for battery-powered microcontroller projects.

The Feather 32u4 Basic Proto combines the proven ATmega32u4 microcontroller with built-in prototyping space, giving you both processing power and room to customise your project directly on the board.

At its core is an ATmega32u4 running at 8 MHz with 3.3V logic — the same setup used on the Flora. It features 32KB of Flash and 2KB of RAM, along with native USB support. This means no separate USB-to-serial converter chip is required, and the board can also emulate USB devices such as a mouse, keyboard, or MIDI device. The Feather 32u4 is fully supported in the Arduino IDE and works with a wide range of existing sensors and libraries.

For portable use, the board includes a JST connector for 3.7V Lithium polymer batteries and built-in battery charging. It can run directly from the micro USB connector without a battery, or automatically switch to USB power when connected for charging. A built-in voltage divider connects the battery to an analogue pin, allowing you to monitor battery voltage in software.

The Basic Proto version includes a small onboard prototyping area, making it easy to add simple components such as buttons or sensors without needing a separate breadboard.

Each board comes fully assembled and tested, with a USB bootloader pre-installed for quick setup in the Arduino IDE. Header pins are included (unsoldered) for use with breadboards.

Please note: Lipoly battery, breadboard and USB cable are not included.

Features

• ATmega32u4 @ 8MHz with 3.3V logic/power
• 3.3V regulator with 500mA peak current output
• USB native support, comes with USB bootloader and serial port debugging
• You also get tons of pins - 20 GPIO pins
• Hardware Serial, hardware I2C, hardware SPI support
• 7 x PWM pins
• 10 x analogue inputs (one is used to measure the battery voltage)
• Built in 100mA lipoly charger with charging status indicator LED
• Pin #13 red LED for general purpose blinking
• Power/enable pin
• 4 mounting holes
• Reset button

Specifications

• Measures: 51mm x 23mm x 8mm without headers
• Weight: 4.8 grams

Revision History

• As of July 26, 2023 – we've updated this PCB with Adafruit Pinguin to make a lovely and legible silkscreen - you may get the new PCB or the older version with vector fonts - both are identical other than the fancy silkscreen.

Resources

• Datasheet
• Tutorial

Package Contents

• 1x Adafruit Feather 32u4 Basic Proto
• 2x 16-pin header