Custom VCNL4040 Proximity and illuminance Sensor -STEMMA QT/Qwiic

describe

The VCNL4040 is a convenient two-in-one sensor with a proximity sensor operating from 0 to 200mm (approximately 7.5 in) and a light sensor operating from 0.0125 to 6553 Lux.

To make life easier and allow you to focus on your important work, we have installed the VCNL4040 on a splitboard PCB with support circuitry, allowing you to work with the little wonders of 3.3V (Feather/Rapberry Pi) or 5V (Arduino/Metro328) logic levels. Also, since it uses I2C, you can easily use two wires (plus power and ground!). Connect them together. We even provide a SparkFun qwiic compatible STEMMA QT connector for the I2C bus, so you don't even need to weld! Simply connect to your favorite micro and you can easily interface with the VCNL4040 using our CircuitPython/Python or Arduino drivers and get close in a short amount of time!

To enable you to adjust the measurements to your situation, the VCNL4040 allows you to adjust the integration time (measuring the length of light) to set the sensitivity of the measurements based on the lighting conditions. The integration time is 80ms, and because the sensor only collects measurements for a short period of time, each measured light bit represents a larger amount of light. Therefore, the range of 80ms integration time (lux) is 6553.5 lux.

If you use longer integration times and get the same number of light measurement "events", you will know that there is relatively less light because we wait longer for light to appear and get the same number, which means the incidence of light events is lower. Therefore, at the integration time of 640 ms, the VCNL4040 measured only 819.2 lux.

It is also worth remembering that as the integration time increases, so does the sensitivity and resolution in the measurement range

In addition to adjusting the sensitivity of the light measurement, you can also change the current and duty cycle of the IR LED driving the proximity detection to adjust the sensitivity of the proximity measurement.

The technical details

Product size: 25.3mm x 17.8mm x 4.6mm/1.0 "x 0.7" x 0.2 "Product weight: 1.7g/0.1oz