Photo-resistor LDR Light Sensor Module

The LDR (Light Dependent Resistor) Sensor Module is a simple and widely used sensor for detecting ambient light levels. It consists of an LDR, a resistor, and additional circuitry to provide easy interfacing with microcontrollers like Arduino or Raspberry Pi. The sensor is often used in various applications where light intensity needs to be measured or monitored.

Module with photoresistor for Arduino. It is controlled by a digital signal, it is powered with the voltage from 3.3 V to 5 V. On board placed was a potentiometer to adjust the sensitivity of photoresistor.

Pinout

• VCC (Power): Connects to 5V or 3.3V (depending on your microcontroller).
• GND (Ground): Connects to ground.
• Digital Output (Optional): Can be used to trigger a high or low signal when a predefined light threshold is met.

Specifications

• Supply voltage: from 3.3 V to 5 V
• Able to detect ambient brightness and light intensity
• Adjustable sensitivity (via blue digital potentiometer adjustment)
• Operating voltage 3.3V-5V
• With fixed bolt hole for easy installation
• Power indicator (Red) and the digital switch output indicator (Green)
• Dimensions (Without Pins): 32 x 14 mm

Working Principle

The resistance of the LDR varies depending on the light falling on it. In the dark, the resistance is high (several megaohms), and in bright light, the resistance drops significantly (to a few hundred ohms). This change in resistance is measured by the module and output as a corresponding voltage.