Adafruit Feather 32u4 Adalogger combines USB, battery charging, and a built-in microSD cardholder, making it an easy, portable solution for Arduino-based data logging projects. Feather is Adafruit’s lightweight, portable development board family—thin, compact, and designed to power projects you can take anywhere. Built to be a new standard for mobile microcontroller platforms, Feather combines USB connectivity, battery support, and a consistent form factor across the range. The Adafruit Feather 32u4 Adalogger is Adafruit’s take on an all-in-one datalogger (or data reader). It’s based on the Feather 32u4 and adds a built-in microSD cardholder, making it ready for logging sensor data or reading files straight out of the box. At its core is the ATmega32u4, running at 8 MHz with 3.3 V logic—the same proven setup used on the Adafruit Flora. The chip provides 32 KB of flash and 2 KB of RAM, along with native USB support. This means no external USB-to-serial chip is needed, and the board can also act as a USB HID device, such as a mouse, keyboard, or USB MIDI controller. Designed with portability in mind, the Feather 32u4 Adalogger includes a JST connector for 3.7 V lithium polymer batteries and onboard battery charging. It can run directly from the micro USB connector, from a battery, or automatically switch between the two when USB power is available. The battery voltage is routed through a resistor divider to an analogue pin, allowing you to monitor battery levels and know when it’s time to recharge. The extra board space is used to add data-logging essentials: * MicroSD cardholder for reading or writing large amounts of data * Green LED on pin #8 for status indication or simple debugging The board ships fully assembled and tested, with a USB bootloader pre-installed for quick use with the Arduino IDE. Header pins are included but not soldered. LiPo battery, microSD card, breadboard, JST cable 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 * 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 - 5.1 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 Adalogger * 2x 16-pin headers https://elecena.pl/product/22712620/adafruit-feather-32u4-adalogger 2023-03-06 https://elecena.pl/product/22712620/adafruit-feather-32u4-adalogger 2023-12-27 https://elecena.pl/product/22712620/adafruit-feather-32u4-adalogger 2024-09-19 https://elecena.pl/product/22712620/adafruit-feather-32u4-adalogger 2024-11-29 https://elecena.pl/product/22712620/adafruit-feather-32u4-adalogger 2024-11-30 https://elecena.pl/product/22712620/adafruit-feather-32u4-adalogger 2025-04-09 https://elecena.pl/product/22712620/adafruit-feather-32u4-adalogger 2025-11-28 https://elecena.pl/product/22712620/adafruit-feather-32u4-adalogger 2025-11-29 https://elecena.pl/product/22712620/adafruit-feather-32u4-adalogger 2026-01-08