DFROBOT Beetle - The Smallest Microcontroller

Ultra-Compact Design: 20mm×22mm thumb-sized design is ideal for wearables and embedded systems, featuring wide-spaced pads for seamless conductive sewing and textile integration.
No-Solder, Sewable Design​​ – ​​V-shaped gold-plated pads​​ let users twist wires or stitch directly onto fabric with conductive thread. Ideal for beginners, classrooms, and rapid prototyping—no soldering iron needed.
Plug-and-Play with Arduino IDE​​ – Program via Micro USB. Leverage Leonardo’s USB-HID to create keyboards, mice, or game controllers. Directly download and debug programs via Micro USB interface, no need for programmer
Low-Power & Expandable: 10 digital pins + 5 analog inputs with 3V coin battery support | Optimized for long-term wearable use, compatible with SPI/I2C expansion via minimal wiring