An ambient light intensity sensor is used in many devices such as a trigger for home automation system and adjusting LCD backlight in mobile devices.
This is a digital light intensity sensor module with BH1750FVI chip on board. This module uses I2C interface to connect to a microprocessor/microcontroller board such Arduino, Raspberry Pi or Beaglebone Black.
The BH1750FVI is a calibrated light intensity sensor. It has a built-in 16-bit analog to digital converter, so it can give you a number from 0 to 65535. The output can be converted to Lux by simply dividing the number by 1.2. This sensor has a spectral response that close to that of the human eye.
The module has 5-pin header. To use it, just connect VCC to power and GND to ground. The SDA and SCL pins are to be connected to the I2C bus interface of your microcontroller. By default, the I2C address of this module is set to 0x23. Unless you want to change this address, the ADD pin can be left unconnected.
