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Product Description (Detailed):

Unlock the power of light detection in your electronic projects with our compact and versatile LDR Sensor 5mm – a Light Dependent Resistor (Photoresistor). This essential component is a cornerstone for hobbyists, students, and engineers looking to integrate light-sensing capabilities into their designs. Measuring just 5mm in diameter, it's perfectly sized for tight spaces and discreet integration into various applications.

The LDR (Light Dependent Resistor), also known as a photoresistor or photocell, operates on the principle of photoconductivity. Its electrical resistance changes inversely with the intensity of light falling on its surface. In low light or darkness, the LDR exhibits a very high resistance (often in the megaohm range), effectively acting as an open circuit. However, as the ambient light increases, the resistance dramatically decreases (down to a few hundred ohms in bright light), allowing more current to flow. This variable resistance makes it incredibly easy to interface with microcontrollers like Arduino, Raspberry Pi, and other platforms, typically by forming a voltage divider circuit.

Commonly made from cadmium sulfide (CdS), this 5mm photoresistor is highly sensitive to the visible light spectrum, making its response similar to that of the human eye. Its applications are vast and include automatic street lights, security alarms, automatic headlight dimmers, camera light meters, display brightness control in consumer electronics, and various DIY automation projects. Simple to use, cost-effective, and highly reliable, our 5mm LDR sensor is the perfect choice for detecting the presence or absence of light, or for measuring varying light intensity to trigger specific actions in your circuits. Add this fundamental light sensor to your toolkit for intuitive and responsive electronic designs.

The 5mm LDR (Light Dependent Resistor) is a passive electronic component that varies its resistance based on the intensity of light falling on it. When the light increases, its resistance drops, making it ideal for detecting light levels in circuits.

With a 5mm diameter sensing head, it is compact enough for miniature embedded systems, yet sensitive enough for reliable performance in home automation, solar lighting, and Arduino-based smart light controllers.

This LDR is widely used in analog light sensors, automatic streetlights, and photodetector applications in educational and industrial settings.

Key Features:

• 5mm sensitive surface for accurate light detection

• Resistance decreases with increasing light intensity

• Works with Arduino, Raspberry Pi, and ESP32

• Ideal for automatic lighting, day/night sensors, and IoT

• Compact size suitable for breadboard and PCB use

• Two-terminal through-hole mounting

Technical Specifications:

How to Use:

1. Connect one terminal to Vcc (3.3V or 5V).

2. Connect the other terminal to GND through a resistor (e.g., 10KΩ).

3. Tap the voltage divider junction to an Arduino analog pin (e.g., A0).

4. Use analogRead() to measure and respond to light levels.

Common use: Voltage divider → LDR + resistor → analog input of Arduino.

Applications:

• Automatic streetlights and smart lighting systems

• Day/night light detectors

• Light-based alarm or automation circuits

• Brightness control for displays and LEDs

• IoT-based light monitoring and logging

• Arduino and Raspberry Pi light sensing projects

Package Includes:

• 1 × 5mm LDR (Light Dependent Resistor)