The light sensor or Light Dependent Resistor (LDR) (PGM5506) is used to measure intensity of light.

When light falls on the sensor, the resistance of the LDR changes.

Examples:

1. Automatic Light- LDR based: sensor measures natural light in the room to switch the light on/off accordingly.
2. Alarm clock: sensor measures sunlight entering in the room to sound morning alarm.
3. Night-light for elderly people: sensor measure when there is less light in the room to turn on a night light for elderly people who cannot switch it on manually.

Units:

• Intensity: lux

Pin:

• A1 pin on the SNT Kit PCB. (the light sensor is on the PCB and does not need other wire connections)

Code

• Click here for the code to test your light sensor.