Seeed Studio XIAO SAMD21

Seeed Studio XIAO SAMD21
The Seeed Studio XIAO SAMD21, which used to be named Seeeduino XIAO, is the first debut of the Seeed Studio XIAO family, a series of powerful thumb-size dev boards compatible with Arduino. It carries the powerful ATSAMD21G18A-MU which is a low-power microcontroller. On the other hand, this little board has good performance in processing but needs less power. It is designed in a tiny size and can be used for wearable devices and small projects.
The Seeed Studio XIAO SAMD21 is one of the smallest yet most powerful Arduino-compatible development boards on the market. Now available at Burk.pk, this tiny board delivers robust performance for embedded systems, wearables, and compact IoT projects.
Powered by the SAMD21G18 chip, it features a 32-bit ARM Cortex-M0+ processor running at 48MHz, with 256KB flash memory and 32KB SRAM. Despite its ultra-small footprint?just 20 x 17.5 mm?the XIAO SAMD21 supports serious development tasks.
Seeed Studio XIAO SAMD21 has 14 PINs, which can be used for 11 digital interfaces, 11 mock interfaces, 10 PWM interfaces (d1-d10), 1 DAC output pin D0, 1 SWD pad interface, 1 I2C interface, 1 SPI interface, 1 UART interface, Serial communication indicator (T/R), Blink light (L) through pin multiplexing. The colors of LEDs(Power, L,RX,TX) are green, yellow, blue, and blue. Moreover, Seeed Studio XIAO SAMD21 has a Type-C interface that can supply power and download code. There are two reset buttons, you can short-connect them to reset the board.
Features?

Powerful CPU: ARM? Cortex?-M0+ 32bit 48MHz microcontroller(SAMD21G18) with 256KB Flash,32KB SRAM.
Flexible compatibility: Compatible with Arduino IDE.
Easy project operation: Breadboard-friendly.
Small size: As small as a thumb(21?17.8mm) for wearable devices and small projects.
Multiple development interfaces: 11 digital/analog pins, 10 PWM Pins, 1 DAC output, 1 SWD Bonding pad interface, 1 I2C interface, 1 UART interface, 1 SPI interface.

Specification

Item
Value

CPU
ARM Cortex-M0+ CPU(SAMD21G18) running at up to 48MHz

Flash Memory
256KB

SRAM
32KB

Digital I/O Pins
11

Analog I/O Pins
11

I2C interface
1

SPI interface
1

QTouch
7?(A0,A1,A6,A7,A8,A9,A10)

UART interface
1

Power supply and downloading interface
Type-C

Power
3.3V/5V DC

Dimensions
21?17.8?3.5mm

Hardware Overview of Seeed Studio XIAO SAMD21
Perfect For:

Miniature sensor nodes

Wearables and portable electronics

IoT product prototypes

Smart home automation

DIY keyboards and HID devices

Educational embedded projects

The board comes with a USB-C connector and supports native USB communication. That means you can create custom USB devices like keyboards, mice, or MIDI controllers?no extra chips needed.
It also features castellated pads, making it easy to solder directly onto a custom PCB. This is ideal for moving from prototype to production without redesigning your circuit.
Why Choose XIAO SAMD21?

Tiny size but fully functional

Supports Arduino, CircuitPython, and PlatformIO

Low power use for energy-efficient systems

Reliable performance with wide community support

USB HID and serial functionality in a single board

Package Includes

1 x Seeed Studio XIAO SAMD21