Sonoff Dongle Light LMG21 USB Zigbee Adapter

The SONOFF Dongle-LMG21 (Dongle Lite MG21) is a compact USB Zigbee 3.0 coordinator that lets you create fast, reliable local control with Home Assistant, Zigbee2MQTT, openHAB, and other platforms. Built on the EFR32MG21 radio, the hardware provides a stable Zigbee mesh network, allowing bulbs, switches, and sensors from different brands to be paired and controlled within a single system.

The dongle works in a PlugPlay manner on Windows, Ubuntu, and Raspberry Pi OS (including Docker environments), and its external, ≤180° adjustable antenna delivers better range. For advanced users, flashable firmware is available (Zigbee NCP/Router, OpenThread RCP, MultiPAN), enabling configuration for multiple network roles as needed.

A cost-effective entry-/mid-tier solution for building your own Zigbee network with DIY-focused community support. Ideal as the backbone of small to medium smart homes.

About the SONOFF brand

SONOFF is one of the best-known brands in the DIY smart home community. Their portfolio includes Wi-Fi and Zigbee relays, switches, sensors, and gateways that offer great value and flexible integration with environments such as Home Assistant, eWeLink, openHAB, and Zigbee2MQTT.

Key Product Features

• Compact Zigbee coordinator: build a stable Zigbee 3.0 mesh network with cross-brand device pairing.
• Wide platform support: works with Home Assistant (ZHA), Zigbee2MQTT, openHAB, ioBroker, Domoticz, and Jeedom.
• PlugPlay setup: quick commissioning on Windows, Ubuntu, Raspberry Pi OS, and in Docker environments.
• Flashable firmware: Zigbee NCP/Router, OpenThread RCP, and MultiPAN modes for advanced configurations.
• External antenna: ≤180° adjustable for improved signal strength and range.

Smart Home Protocols and Platform Compatibility

• Supported protocols: Zigbee 3.0 (default); in advanced mode OpenThread RCP / MultiPAN (depending on firmware).
• Compatible platforms: Home Assistant (ZHA), Zigbee2MQTT, openHAB, ioBroker, Domoticz, Jeedom.
• Local control: manage paired Zigbee devices over LAN without the cloud.
• Operating systems: Windows, Ubuntu, Raspberry Pi OS; also usable with Docker.

Smart Features

• Create a Zigbee mesh: build a stable, scalable network with your own coordinator and unify devices.
• Cross-brand device management: integrate bulbs, switches, and sensors from various manufacturers.
• Advanced modes: with firmware swap, set up Router/RCP/MultiPAN modes for specialized use cases.

Electrical Functions

• Power supply: 5 V⎓ / 500 mA (via USB).

Other Characteristics

• Enclosure: PC+ABS housing.
• External antenna: adjustable, ≤180°.
• DIY focus: community guides available for advanced features (e.g., firmware flashing).

Technical Specifications

• Model: SONOFF Dongle-LMG21 (Dongle Lite MG21)
• SoC / radio: Silicon Labs EFR32MG21
• Protocol: Zigbee 3.0 (flashable: Zigbee NCP/Router, OpenThread RCP, MultiPAN)
• Compatibility: Home Assistant (ZHA), Zigbee2MQTT, openHAB, ioBroker, Domoticz, Jeedom
• OS support: Windows, Ubuntu, Raspberry Pi OS; Docker
• Power: 5 V⎓ / 500 mA (USB)
• Dimensions: 133 × 18.6 × 10.1 mm
• Operating temperature: 10–60 °C
• Humidity: 5–95% RH
• Note: Thread/MultiPAN features require a firmware update; setup is recommended for advanced users.