Adafruit QT Py - SAMD21 Dev Board with STEMMA QT
We have ✅ 3 available of the AF-4600 in our Sydney warehouse. An extra 100 units available with a short lead time.
The Adafruit QT Py SAMD21 is the original QT Py — a tiny development board built around the ATSAMD21E18 (ARM Cortex-M0+ at 48 MHz) with native USB, a STEMMA QT connector, and an RGB NeoPixel. It's the same chip found in the popular Trinket M0 and GEMMA M0, now in a Seeed Xiao-compatible form factor with plug-and-play I2C.
With native USB support, it shows up as a disk drive for drag-and-drop CircuitPython coding, and can act as a USB keyboard, mouse, MIDI device, or serial console. The STEMMA QT / Qwiic connector gives you solderless I2C access to hundreds of sensors, and castellated pads make it easy to embed in custom PCB designs.
Key Features
- ATSAMD21E18 Processor – 48 MHz ARM Cortex-M0+ with 256 KB flash and 32 KB RAM
- Native USB – USB serial console, keyboard/mouse HID, MIDI, and disk drive
- USB-C Connector – For programming, power, and USB device functions
- STEMMA QT / Qwiic Connector – Plug-and-play I2C for sensors and accessories
- RGB NeoPixel LED – Built-in with controllable power pin for low-power usage
- 11 GPIO Pins – 9× 12-bit ADC, 1× true analogue output (DAC), 9× PWM, 6× capacitive touch
- Hardware I2C, UART, SPI & I2S – Full peripheral support
- CircuitPython & Arduino – Full support for both platforms
- 3.3 V Regulator – AP2112 with 600 mA peak output
- Optional SPI Flash – SOIC-8 pads on the bottom for adding external flash storage
- Reset Button – Quick restart or bootloader entry
- Seeed Xiao Compatible – Same size and pinout with castellated pads
Also Consider
- QT Py RP2040 – Dual-core with 8 MB flash and PIO state machines
- QT Py ESP32-S2 – Single-core with Wi-Fi, native USB, and 2 MB PSRAM
- QT Py ESP32-S3 – Dual-core with Wi-Fi + BLE and native USB
- QT Py ESP32-C3 – RISC-V with Wi-Fi + BLE
Ideal For
- Simple CircuitPython and Arduino projects
- USB HID devices (keyboards, mice, MIDI controllers)
- Compact I2C sensor projects with STEMMA QT
- Capacitive touch interfaces
- Embedding into custom PCBs via castellated pads
Resources
The Adafruit QT Py - SAMD21 Dev Board with STEMMA QT appears in the following collections:
