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Compact Datalogging Power with the Feather M0 Adalogger
The Adafruit Feather M0 Adalogger combines a fast ATSAMD21G18 ARM Cortex M0 microcontroller with a built-in microSD card holder, making it a great all-in-one board for portable data logging, sensor recording, and battery-powered projects.
It is part of Adafruit’s Feather family, so you get a thin, lightweight design with native USB, LiPo battery charging, and plenty of GPIO in a compact board that is easy to use for logging data on the go.
Important: This board uses 3.3V logic and includes a built-in microSD card slot and 100mA LiPo charger. The LiPo battery, microSD card, and USB cable are not included.
Why you'll love it
- Built for logging: Onboard microSD card holder for easy data storage
- Powerful Cortex M0 MCU: ATSAMD21G18 running at 48MHz
- Portable-ready: Built-in LiPo battery charging for field projects
- Native USB support: Easy programming and serial debugging without extra USB-to-serial hardware
- Compact Feather form factor: Lightweight and easy to integrate into mobile builds
- Battery monitoring: Battery voltage is connected through a divider to an analog pin for monitoring in code
What you can build
This board is ideal for environmental data loggers, portable sensor recorders, battery-powered monitoring devices, wearable logging systems, GPS data recorders, science projects, and long-running prototypes that need local storage on a microSD card.
Starter bundles
Pair it with a microSD card, 3.7V LiPo battery, micro USB cable, and a sensor module to build a ready-to-deploy portable data logger.
Recommended add-ons
Add an OLED display, GPS module, IMU sensor, or FeatherWing accessory to expand your project into a complete mobile logging system.
Technical specifications
| Product | Adafruit Feather M0 Adalogger |
|---|---|
| Main MCU | ATSAMD21G18 ARM Cortex M0 |
| Clock Speed | 48 MHz |
| Logic Voltage | 3.3V |
| Flash Memory | 256 KB |
| RAM | 32 KB |
| GPIO | 20 GPIO pins |
| PWM Outputs | 8 |
| Analog Inputs | 10 |
| Analog Output | 1 × 10-bit DAC |
| Interfaces | Hardware Serial, I2C, and SPI |
| USB | Native USB with USB bootloader and serial debugging |
| Storage | Built-in microSD card holder |
| Battery Support | 3.7V LiPo/Li-Ion battery connector with built-in 100mA charger |
| Regulator | 3.3V regulator with 500mA peak current output |
| Extra LEDs | Pin 13 red LED and pin 8 green LED |
| Other Features | Power/enable pin, 4 mounting holes, reset button |
| Dimensions | 22.8mm × 51.6mm × 8mm |
| Weight | 5.3g |
Pinout & power notes
The Feather M0 Adalogger gives you a strong mix of digital, analog, and communication pins in a compact layout. It supports hardware Serial, I2C, and SPI, making it easy to connect displays, sensors, radios, and storage-based projects.
You can power it from micro USB while programming, or from a 3.7V LiPo battery for portable use. When USB is connected, the board automatically switches power and recharges the battery. You can also monitor battery voltage in software through the onboard divider.
What’s in the box
1 × Adafruit Feather M0 Adalogger
Header strip included for soldering
Frequently Asked Questions
Does this include a microSD card?
No. The board has a microSD card holder, but the card itself is sold separately.
Can I use this as a portable datalogger?
Yes. That’s exactly what it is built for, especially when paired with a LiPo battery and microSD card.
Is it Arduino compatible?
Yes. It comes with a USB bootloader and is designed for use with the Arduino IDE.
Does it have built-in battery charging?
Yes. It includes a 100mA LiPo charging circuit for 3.7V LiPo/Li-Ion batteries.
Is this a 5V board?
No. This board uses 3.3V logic, so connected peripherals should also be compatible with 3.3V logic levels.
Manila stock. Order before 16:00 PHT, ships today via J&T or LBC. Provincial: 1–3 working days.
Schools / class POs: we accept Purchase Orders for accredited schools and universities. contact us with your PO details.
Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
Compatibility & downloads
// downloads
- GitHub PCB repo git
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