XIAO SAMD21

by Seeed Studio

Seeeduino XIAO is an Arduino compatible microcontroller based on the ARM® Cortex®-M0+ 32bit 48MHz SAMD21G18

Features

  • ARM® Cortex®-M0+ 32bit 48MHz microcontroller (SAMD21G18) with 256KB Flash, 32KB SRAM
  • Compatible with Arduino IDE
  • Breadboard-friendly
  • Small size: As small as a thumb (20x17.5mm) for wearable devices and small projects.
  • 11 x digital/analog pins
  • 10 x PWM Pins
  • 1 x DAC output
  • 1 x SWD Bonding pad interface
  • 1 x I2C interface
  • 1 x UART interface
  • 1 x SPI interface.

Seeeduino XIAO carries the powerful CPU-ARM® Cortex®-M0+(SAMD21G18) which is a low-power Arduino microcontroller. Its small footprint and low power consumption, combined with its high performance, make this ideal for Arduino wearable devices and small projects.

In addition to the strong CPU, Seeeduino XIAO also has 14 GPIO PINs, which can be used for 11 analog PINs, 11 digital PINs, an I2C interface, a UART interface, and an SPI interface.

Some PINs have various functions, A1/D1 to A10/D10 Pins have PWM functions and Pin A0/D0 functions as a DAC which means you can get true analog signals rather than PWM signals when you define it as an analog pin, that’s why 14 GPIO PINs can realize more I/O PINs and interfaces.

Moreover, Seeeduino XIAO has a  USB-C interface which can supply power and download code. There are power pads at the back of the XIAO which support batteries and make it ideal for wearable device design. As well as the power LED, there is a user LED on board for a better coding experience. Usually a Dev. Board as small as this size will use the chip’s inner crystal oscillator for time fixing, in order to make the clock more accurate, Seeeduino XIAO layouts an extra 32.768KHz to make the clock more stable.

 Seeeduino XIAO is perfectly compatible with the Arduino IDE, you can easily develop small projects with the help of the large and comprehensive Arduino library.

Attention: All the I/O pins are 3.3V, please do not input more than 3.3V, otherwise, the CPU may be damaged.

Click here for the Seeeduino XIAO WIki, which contains more specific detail as well as a handy getting started guide

Specification

  • CPU: ARM Cortex-M0+ CPU(SAMD21G18) running at up to 48MHz
  • Storage: 256KB Flash,32KB SRAM
  • I/O PINs: 14 GPIO PINs,11 analog PINs, 11 digital PINs, 1 DAC output Pin
  • Interface: 1 I2C interface,1 UART interface, 1 SPI interface
  • Power supply and downloading interface: USB Type-C interface
  • LEDs: 1 user LED, 1 power LED, two LEDs for serial port downloading
  • Reset button: two reset button short connect to reset
  • Power Pads: For the battery power supply
  • Software compatibility: Compatible with Arduino IDE
  • Projection cover for protecting the circuit
  • Dimensions: 20x17.5x3.5 mm

Typical Application

  • Wearable devices
  • Rapid prototyping (directly attached to the expanded PCB as a minimal system)
  • DIY keyboard
  • USB development (USB to multi-channel TTL/USB host mode, etc.)
  • A scenario where you need to read multiple mock values The DAC output

34 customer reviews

2 years ago
I always used Trinket M0 for installs on certain consoles but now they're out of stock almost everywhere and if you found them they're selling for double or triple the price. I heard about the XIAO SAMD21 and for certain projects I've used the uf2 files for it existed so thought I'd give it a try and it works amazingly. Only two things I'd say, I had to figure how to program it by bridging the two pads next to the USB to get PC to see it as a usb storage device and usb conenctor pins are close to each other, so if you're removing the USB port and soldering to the pads directly it can be testing as they're close to each other.
by Amr about XIAO SAMD21 via REVIEWS.io
2 years ago
I got one of these to start using instead of Arduino Nanos. Firstly the size...really small and neat. Secondly, the power, it hardly uses any power compared to the Nano. As a newcomer to Coding (aged 64), I still have a lot to learn. So far I've had a few issues on projects that are fine on a Nano, but won't on this device (no EEPROM for instance). All in all 5* for a CHEAP but POWERFUL device.
by Richard about XIAO SAMD21 via REVIEWS.io
2 years ago
For me, this little board is the perfect replacement for a Nano33 iot I was using in my project. I didn't need the Bluetooth or WiFi capability of the Nano and really needed a smaller footprint. This board uses the same processor, Samd21, as the Nano33 and so required just some small IO changes to get it up and running. Very pleased.
by Anonymous about XIAO SAMD21 via REVIEWS.io
3 years ago
Just a fantastic MCU, especially for the price. I used to use Trinkets as my cheap MCU option, but this is cheaper and far more powerful, with more pins and more pin flexibility. The Xiao is likely to become my go-to MCU for all of my non-Photon projects
by Talon about XIAO SAMD21 via REVIEWS.io
3 years ago
A great litte board for learning coding. Currently I have only used it on Ardiuino. I am using it to learn more about SPI and I2C interfaces. There are also plenty of GPIO options especially ADC which other boards are restricted. Before long I shall be incorporating it in a larger project.
by Philip about XIAO SAMD21 via REVIEWS.io
4 years ago
Great little development board, tiny but packed with features, it's my new favourite go to board. Unless you need lots of IO pins this does it all.
by Anonymous about XIAO SAMD21 via REVIEWS.io
4 years ago
I love these Arduino compatible Seeeds. Small and perfectly formed.
by Glen about XIAO SAMD21 via REVIEWS.io
4 years ago
Little an powerful. Perfect for my macro keyboard project!
by Martino about XIAO SAMD21 via REVIEWS.io
4 years ago
This is a timely addition to the Arduino-compatible stable. It's small, low power with good memory and an ARM 32 bit processor. It has all the functionality I need for building remote environmental sensors including I2C and UART. It doesn't have a reset button but is powered through a USB-C: useful for development and debugging. Pimoroni have it on sale at a low price too. I'm going to buy more.
by Ric about XIAO SAMD21 via REVIEWS.io
4 years ago
Great little board, completely overkill for what I needed but the price and USB-C meant it was a no-brainer!
by Anonymous about XIAO SAMD21 via REVIEWS.io
4 years ago
I cannot stress enough that you MUST get a couple of these, i got one to try out, and by the end of the 3rd day, i already had 4 ideas for them, plus a case 3d printing! cheaper than the pro-micro if youre looking for a usb HID controller, plus they are cheap as chips (excuse the pun haha)
by Clifford about XIAO SAMD21 via REVIEWS.io
4 years ago
Powerful and very small, really useful for low power projects.
by Christopher about XIAO SAMD21 via REVIEWS.io
4 years ago
Does what it says in the tin, makes an excellent mouse jiggler
by Anonymous about XIAO SAMD21 via REVIEWS.io
4 years ago
Lots of features, small package, great price. Shipping was super quick as well. Sticker with pin numbers optional (3 options along with a blank white or leave it without - see pic).
by Colin about XIAO SAMD21 via REVIEWS.io
4 years ago
It's tiny - but it has just enough pins for my project!
by William about XIAO SAMD21 via REVIEWS.io
4 years ago
It’s size and flexibility make this the goto processor for most projects now
by Colin about XIAO SAMD21 via REVIEWS.io
4 years ago
Everything arrived within time and perfectly packaged. I fact, it was so well packaged that the outer envelope was damaged, but the inner one was intact. Thank you for such detail, which prevented me to ask for a reimbursement and gained you my appreciation and 5 stars ;)
by Fabio about XIAO SAMD21 via REVIEWS.io
4 years ago
Astounding, 11 IO.Pins, 48Mhz, works with Arduino IDE a treat. Excellent value. N.B. Addition commands to use full 12 bit A2D and 10 bit D2A.
by Robin about XIAO SAMD21 via REVIEWS.io
4 years ago
Bought 2, one failed after an hour. The second runs hot even when These run hot even idle connected to a pcs USB. Nice form factor but I wouldn't trust this to run for long.
by David about XIAO SAMD21 via REVIEWS.io
4 years ago
Very straightforward to use with Arduino IDE (I ordered 5). Comprehensive Seeeduino wiki.
by Olujide about XIAO SAMD21 via REVIEWS.io
4 years ago
Tiny, nice and easy to use. Low amount of memory.
by Maximilian about XIAO SAMD21 via REVIEWS.io
4 years ago
These little boards are FANTASTIC! At this price, there’s no point using a Nano clone unless I specifically need a 5V output!! Also, they’re really quite tiny :•) There are occasional “computer can’t find the board” shenanigans, but these are overcome by resetting the board. I have a few of these now, and recently used one at work as a PWM controller…
by Craig about XIAO SAMD21 via REVIEWS.io
4 years ago
First time I've seen a seller in the UK at a good price as well. Great wee piece of kit. Thanks!
by Sandy about XIAO SAMD21 via REVIEWS.io

3 user photos