This light sensor module is very sensitive to ambient light. Usually used to detect the brightness and intensity of ambient light. The sensitivity of the signal detection can be adjusted by means of a potentiometer. LDR (Light Dependent Resistor) means a light-dependent resistor or photoresistor, it is a passiveelement of a circuit with a resistor that has a variable resistance depending on the light intensity. It has 4 pins and 2 LEDs that show the state of the digital power supply and output. The module’s construction is based on LM393 circuit. The sensor is powered from 3.3 V to 5 V.

LDR light sensor design

The sensor module consists of:

• A potentiometer, which is used to set the trigger level
• 2 LEDs that show the power and digital output (DO) status
• 4 pins: VCC, GND, DO, AO
• Photoresistor sensitive to light
• LM393
• Capacitors

LDR sensor specifications

• Type of sensor: digital
• Supply voltage: 3.3 V to 5 V
• 2 LEDs to indicate power supply and digital output
• Construction based on LM393
• Dimensions of the plate: 32 x 14 x 5 mm