The AVR-IoT cellular mini development board is a hardware platform to evaluate and develop IoT solutions with the Microchip AVR128DB48 AVR® microcontroller, ATECC608B secure element, and the Sequans Monarch 2 GM02S cellular module. Included with the development board is a SIM card from Truphone with 150 MB data ready for activation.

The sequans Monarch 2 GM02S requires a connection to a LTE-M capable cellular network. With a connection to a capable cellular network the ATECC608B can be used to authenticate the hardware with the cloud to uniquely identify every board.

Out of the box, the MCU comes preloaded with a firmware image that enables you to quickly connect and send data to the Microchip Sandbox in AWS using the on-board temperature and color sensors. Once you are ready to build your own custom design, you can easily get started with development using the Arduino. The AVR-IoT Cellular Mini has full Arduino support through a library built on top of the open-source DxCore.

The AVR-IoT cellular mini is a development board from Microchip to develop cellular IoT applications.


Full arduino support through a library built on top of the open-source DxCore

All the basic building blocks to create secure IoT applications (AVR® microcontroller, secure element and a cellular modem)

Free 150MB 90-day SIM card from Truphone, providing coverage across many countries

Bundled antenna in the box

On-board debugger, no need for any external tools

Battery charging circuitry with connectors

Complete AWS support with easy provisioning through the IoT provisioning tool

Built and designed to be familiar to makers, featuring a Adafruit feather form-factor and a qwiic/stemma connector

The board focuses on being accessible and easy to use by makers. It has the Adafruit Feather form factor, and can connect to sensors through a qwiic / Stemma I2C bus.


The block diagram gives an overview of the board components. The main components are

  • Microcontroller: AVR128DB48
    • AVR® Microcontroller from Microchip. Features 128K of flash, Multi-Voltage I/O, and a set of internal operational amplifiers.
  • Secure Element: ECC608B
    • A cryptographic IC providing security protocols and secure storage of private keys.
  • Cellular modem: Sequans monarch 2


  • AVR128DB48 AVR® Microcontroller
  • ATECC608B cryptoAuthentication™ device
  • 25CSM04 serial EEPROM - 4 Mb
  • Sequans monarch 2 GM02S cellular module
  • 824MHz-2170MHz cellular flexible antenna
  • Prepaid SIM card from Truphone - 150 MB data included
  • Nano SIM card holder
  • eSIM footprint
  • Five user LEDs
  • Two mechanical buttons
  • VMK3-9002 32.768 kHz crystal
  • VEML3328 color sensor
  • MCP9808 temperature sensor
  • Adafruit feather compatible edge connector
  • Qwiic® I2C connector
  • On-board debugger
  • Board identification in Microchip studio and Microchip MPLAB® X
  • One green power and status LED
  • Virtual serial port (USB CDC)
  • Two logic analyzer channels (debug GPIO)
  • Arduino compatible with its own Cellular Arduino library
  • USB, battery, and external-input power options
  • MCP73830 Li-Ion/LiPo battery charger, with charge status LED
  • Two fixed power domains, 1.8V and 3.3V

AVR-IoT cellular mini development board

Cellular mini board, AVR128DB48, ATECC608B, atmega family, megaAVR

AVR128DB MCU family

The AVR-IoT cellular mini board is based upon Microchip’s new AVR128DB MCU family