An atom is the smallest particle of a chemical element that can exist. But when it comes to development boards, the smallest one on the market is the ESP32-based M5Stack ATOM, with an extremely small size of only 24×24mm. It is mainly designed for portable embedded systems and IoT development projects. M5Stack ATOM is truly cost-effective not just because of its small size, but also because it has no integrated battery.

M5Stack has actually announced two types of units in the ATOM series, ATOM Matrix and ATOM Lite. The ATOM Matrix is the latest and most compact development board in the M5Stack development kit series. Don't judge it by its small size, though! It comes packed with tons of features, Wi-Fi, Bluetooth, 5×5 RGB LED Matrix with a push button, an IMU sensor (MPU6886) and six GPIOs.

The MCU is Espressif’s ESP-PICO System-in-Package (SiP) module. The ATOM Matrix has everything you need for projects with a display.

ATOM Matrix Features

• USB Type-C
• ESP32 PICO-based
• 4 MByte flash
• 1 Programmable button
• 5 × 5 RGB LED matrix panel
• Infrared LED
• Reset button
• 2.4G SMD Antenna: Proant 440
• MPU6886 Inertial Sensor
• 6 × GPIOs (Dupont Pins)
• 4Pin PH2.0 interface
• Program Platform: MicroPython, Arduino
• Product Size: 24 × 24 × 14mm
• Product weight: 14g

ATOM Matrix

However, the ATOM Lite, which is presented below, is even cheaper than the ATOM Matrix. The reason for this is that the ATOM Lite is fairly minimal. In other words, if a status LED and a single button is all you need for your project, then the ATOM Lite will suffice.

ATOM Lite Features

• USB Type-C
• ESP32-based
• Case Material: PC + ABS
• 4 MByte flash
• 1 × Reset button
• 1 × Neo LED
• 1 × Programmable button
• 1 × Infrared
• 2.4G Antenna: Proant 440
• 6 ×* GPIO (Dupont Pins)
• 4P PH2.0 interface
• Program Platform:MicroPython, Arduino
• Product Size：24 × 24 × 10mm
• Product weight: 12g

ATOM Lite

Various different projects can be implemented using ATOM. It can be embedded in devices you would like to connect to the Internet, such as smart-home controllers, alarm-, temperature- and humidity-sensors, smart keys, etc. 

ATOM’s sensors could also be used in the collection of manufacturing data or for developing a centralized controller in industrial automation application scenarios. This is a good way to improve production efficiency and prevent unforeseen breakdowns.

Furthermore, ATOM Matrix and ATOM Lite can be currently programmed, using Arduino, Micropython, Visuino and UIFlow. UIFlow is a Web-based IoT programming system developed by M5Stack. The Blockly visual interface is clear and easy to program. 

In the near future, M5ATOM will be enhanced with various peripherals such as the soon-to-be-released ATOMIC and ATOMECHO.