INTRODUCTION AND BASIC OPERATION
The VCNL4100 is a fully integrated proximity and ambient light sensor. It combines an infrared emitter and photodiode for proximity measurement, ambient light sensor (ALS), and signal processing IC in a single package with an 8-bit ADC. The device provides ambient light sensing to support conventional backlight and display brightness auto-adjustment, and proximity sensing to recognize objects up to a distance of 1 m (40″).
This stand-alone component greatly simplifies the use and design-in of a proximity sensor (PS) in consumer and industrial applications, because the embedded IRED as well as photodiode are exactly matched to each other. The VCNL4100 features a miniature, surface-mount 8.0 mm by 3.0 mm leadless package (LLP) with a height of 1.8 mm. The device is designed specifically to meet the requirements for applications where objects need to be identified at far distances.
Through its standard I2C bus serial digital interface, it allows easy access to a “proximity signal” and “light intensity” measurements. The programmable interrupt function offers wake-up functionality for the microcontroller when a proximity event or ambient light change occurs, which reduces processing overhead by eliminating the need for continuous polling.