M5Stack light unit (U021) – simple light sensor with a photoresistor

A simple, inexpensive light sensor: it detects whether it is light or dark. Good when you only need to know "day or night", for example to switch on a lamp at dusk.

Good to know

The photoresistor gives a relative value, not lux. If you want exact lux values, choose the DLight (U136).

Works with

• ESPHome (adc or binary_sensor gpio)
• Home Assistant via ESPHome
• M5Stack controllers with an analogue input on the Grove port

You also need

A controller, for example the ATOM Lite. Grove cable included.

Specifications

• Sensor: photoresistor
• Output: analogue and digital (threshold adjusted with a potentiometer)
• Connector: Grove (HY2.0-4P)

Manufacturer and documentation

Manufacturer: M5Stack Technology Co., Ltd, Block A10, Expo Bay South Coast, Fuhai Street, Bao'an District, Shenzhen, China, [email protected]. EU representative: Success Courier SL, Calle Rio Tormes 1, Planta 1, Derecha, Oficina 3, 28947 Fuenlabrada, Madrid, Spain, [email protected].

• Product documentation (M5Stack)
• Manufacturer certifications (CE/RoHS)

End-of-life electronics must be taken to separate collection. Read about e-waste.