Adafruit TSL2591 High Dynamic Range Digital Light Sensor (STEMMA QT)

The TSL2591 is an advanced digital luminosity sensor designed to measure light across a broad range of conditions. Ideal for applications requiring precise light measurements, this sensor offers a significant upgrade over low-cost CdS cells. It can accurately calculate lux levels and is configurable for different gain and timing ranges, enabling it to measure light from 188 µLux up to 88,000 Lux in real-time.

What sets this sensor apart is its ability to detect both infrared and full-spectrum light. Unlike most sensors that only detect visible light or infrared, the TSL2591 provides separate measurements for infrared, full-spectrum, and human-visible light, offering a more accurate representation of what the human eye perceives. With an impressive 600,000,000:1 dynamic range, it outperforms sensors like the TSL2561, though it has a fixed I2C address.

Thanks to its built-in ADC, the TSL2591 is compatible with any microcontroller, even those lacking analog inputs. The sensor's low current draw (0.4mA during sensing and less than 5 µA in power-down mode) makes it ideal for low-power data-logging applications.

For ease of use, the sensor features SparkFun qwiic compatible STEMMA QT connectors for the I2C bus, eliminating the need for soldering. You can quickly connect it to your favorite microcontroller with a plug-and-play cable. While the QT cable isn't included, it's available separately in the shop.

Technical Details:

• Lux Range: 188 µLux sensitivity, up to 88,000 Lux input
• Dynamic Range: 1 to 600,000,000 counts
• Temperature Range: -30°C to 80°C
• Voltage Range: 3.3V to 5V (with onboard regulator)
• Interface: I2C, 7-bit address 0x29 and 0x28
• Dimensions: 19mm x 16mm x 1mm (0.75" x 0.63" x 0.04")
• Weight: 1.1g
• Current Draw: 0.4mA active, less than 5 µA in power-down mode

Revisions:

• October 24, 2023: Added jumper to the LED and updated PCB with clearer silkscreen.
• September 16, 2020: Updated to STEMMA QT standard with mounting holes and connectors.
• November 25, 2020: Added cuttable jumper to disable the onboard green LED.

This sensor is an excellent choice for precise light measurement, whether you’re working on a low-power data logging project or need accurate light detection across different light spectrums.