UV & Ambient Light Sensor RAKwireless RAK12019 (Lite-On LTR-390UV-01)

RAKwireless RAK12019 combines UV sensing and ambient light sensing in a compact WisBlock module. Built around the Lite-On LTR-390UV-01, it can operate as an ALS (Ambient Light Sensor) or a UVS (Ultraviolet Sensor) and provides readings digitally via I2C. In many real deployments, a digital interface is preferred because it’s less susceptible to electrical noise than analog-output light sensors.

The module is designed for practical, real-world lighting environments. It offers 13 to 20 bits effective resolution, a very wide linear dynamic range (1:18,000,000), and an ambient-light response that is close to the human eye. For indoor environments, automatic 50/60 Hz flicker rejection helps maintain stable readings under mains-powered lighting. A built-in temperature compensation circuit supports more consistent results across changing conditions.

Where it fits best:

Greenhouse and indoor farming control, tracking UV levels to protect plants (trigger shading/alerts/logging) and using ambient light data for lighting decisions.

UV level warning systems and outdoor monitoring nodes using UV index thresholds.

Building automation, including daylight sensing for lighting control and window shading/blinds logic.

Prototyping and product development, validating thresholds and integrating light/UV sensing into connected devices.

For low-power designs, the sensor supports sleep operation and lists 1 µA to 110 µA current consumption depending on mode. It also includes programmable interrupts for both ALS and UVS with upper and lower thresholds, enabling event-driven behavior (e.g., only wake/transmit when UV or light crosses a limit). The module is RoHS and halogen-free compliant.