The Feather 32u4 Adalogger is an all-in-one datalogger built around the ATmega32u4, with a built-in MicroSD card holder, USB connectivity, and LiPo battery charging. Ready to log data straight out of the box — just add a MicroSD card and start recording.

The ATmega32u4 runs at 8 MHz with 3.3V logic and includes native USB support, so it can act as a serial device, keyboard, mouse, or USB MIDI controller without needing a separate USB-serial chip. Built-in battery charging and automatic USB/battery power switching make it ideal for portable data logging projects.

Key Features

• ATmega32u4 @ 8 MHz – 3.3V logic, 32KB flash, 2KB RAM
• Native USB – Built-in USB bootloader, serial debugging, and HID device support
• MicroSD Card Holder – For extensive data storage and reading
• 20 GPIO Pins – Including 10 analogue inputs and 7 PWM outputs
• Hardware Serial, I2C & SPI – Full peripheral support
• Built-in LiPo Charger – 100 mA charging with status indicator LED
• Battery Monitoring – Battery voltage routed to an analogue pin via divider
• 3.3V Regulator – 500 mA peak current output
• Pin #8 Green LED – Additional LED for logging status indication
• Pin #13 Red LED – General-purpose blinking

Specifications

• Dimensions – 51 × 23 × 8 mm (without headers)
• Weight – 5.1 g
• Mounting – 4 mounting holes

Also Available

• Feather 32u4 Basic Proto – With prototyping area
• Feather 32u4 Bluefruit LE – With Bluetooth Low Energy
• Feather 32u4 RFM95 LoRa Radio (868/915 MHz)
• Feather 32u4 RFM96 LoRa Radio (433 MHz)
• Feather 32u4 FONA – With cellular connectivity
• Feather 328P – ATmega328P variant

Ideal For

• Portable data logging and environmental monitoring
• Sensor data recording to MicroSD card
• Battery-powered field deployments

Package Contents

• 1× Assembled and tested Feather 32u4 Adalogger
• 1× Header set