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Adafruit GEMMA v2 - Miniature wearable electronic platform

We have ✅ 12 available of the AF-1222 in our Sydney warehouse. An extra 32 units available with a short lead time.

Express post delivery (2-5 business days)

The Adafruit GEMMA V2 is a tiny, coin-sized wearable microcontroller board powered by an ATtiny85 processor. At just 28 mm in diameter, it's small enough to fit into any sewable or wearable project, and affordable enough to dedicate to every build. Program it over USB with the Arduino IDE and bring your wearable ideas to life.

Version 2 upgrades the original GEMMA with a Micro-B USB connector (replacing Mini-B) and adds a convenient on/off switch. Three GPIO pins with sew-friendly pads make it easy to connect sensors, LEDs, and other components using conductive thread or alligator clips.

Key Features

  • ATtiny85 Processor – 8 MHz internal oscillator, 8 KB Flash, 512 bytes SRAM, 512 bytes EEPROM (~5.25 KB available after bootloader)
  • Ultra Compact – Only 28 mm diameter and 7 mm thick
  • Micro-USB Connector – For power and programming via Arduino IDE
  • On/Off Switch – New in V2 for convenient power control
  • 3 GPIO Pins – With 1 analog input, 2 PWM outputs, and hardware I²C support
  • Easy-to-Sew Pads – Large holes for conductive thread or alligator clips
  • Ultra Low Power – Draws only 9 mA while running
  • 3.3V Regulator – 150 mA output, up to 16V input with reverse-polarity, thermal, and current-limit protection
  • Flexible Power – Automatically switches between USB and external battery power
  • Built-in LEDs – Green power LED and red LED on pin 1
  • Reset Button – Enter bootloader or restart your program

Ideal For

  • Sewable wearable electronics and e-textile projects
  • Small, low-cost embedded builds
  • LED jewellery, costumes, and accessories
  • Beginner Arduino projects in a compact form factor

Package Contents

  • 1× Adafruit GEMMA V2 board – Fully assembled and tested
Note: GEMMA is not fully 100% Arduino-compatible. It does not have a serial port for debugging, and some USB 3.0 ports may not recognise the bootloader — use a USB 2.0 port or hub if needed. USB cable not included.
Tip: Want more power and CircuitPython support? Upgrade to the Adafruit GEMMA M0 — same form factor with a 32-bit processor, 256 KB Flash, and native USB. Or grab a complete starter kit: the Gemma Sensor Starter Pack or the Gemma Sequin Starter Pack.

Resources

The Adafruit GEMMA v2 - Miniature wearable electronic platform appears in the following collections:

SKU AF-1222