5mm LDR (Light Dependent Resistor)
5mm LDR (Light Dependent Resistor)
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Looking to buy 5mm LDR (Light Dependent Resistor) at the best price in India? Tech Depot India offers competitive pricing, bulk discounts for orders of 10+ units, and dedicated technical support via email and WhatsApp. Whether you are a hobbyist, student, or professional engineer, we have everything you need for your electronics projects.
A compact 5mm photoresistor that changes resistance based on ambient light intensity - essential for light-sensing circuits, automatic lighting systems, and Arduino/microcontroller projects. Available at Tech Depot India, Bengaluru with fast shipping and full technical support.
Specifications
| Component Type | Light Dependent Resistor (Photoresistor) |
| Sensor Diameter | 5mm |
| Light Resistance (10 Lux) | 8-20 kOhm (typical) |
| Dark Resistance | 1 MOhm (minimum) |
| Peak Wavelength | ~540 nm (green light) |
| Spectral Response | Visible light range (400-700 nm) |
| Maximum Voltage | 150V DC |
| Maximum Power Dissipation | 100 mW |
| Response Time (Rise) | ~20 ms |
| Response Time (Fall) | ~30 ms |
| Operating Temperature | -30 degreesC to +70 degreesC |
| Material | Cadmium Sulfide (CdS) photoconductive cell |
| Package | Through-hole, 2-pin |
| Origin | Original / Authentic |
Why Choose 5mm LDR (Light Dependent Resistor)?
100% Authentic
GST Invoice - A GST invoice is included with every order.
Expert Support - Dedicated technical help on WhatsApp and email.
Pan-India Delivery - Shipped across Bengaluru, Delhi NCR, Hyderabad and all of India.
Trusted by Makers - Used by students, hobbyists and professionals nationwide.
Key Features of 5mm LDR (Light Dependent Resistor)
- Analog Light Sensing: Resistance decreases smoothly as light intensity increases - provides a simple analog signal proportional to brightness.
- Wide Resistance Range: From ~10 kOhm in bright light to over 1 MOhm in complete darkness, offering excellent sensitivity across lighting conditions.
- No Polarity: A passive, non-polarized component - connect either lead to either side of your circuit without worrying about orientation.
- Compact 5mm Form Factor: The most popular LDR size, fitting easily into breadboards, PCBs, and enclosures.
- Breadboard & PCB Friendly: Standard through-hole leads plug directly into solderless breadboards or solder neatly onto perfboards and custom PCBs.
- Low Power Consumption: Draws minimal current, making it ideal for battery-powered and low-power IoT applications.
- Fast Response Time: ~20-30 ms response allows detection of rapid light changes for dynamic applications.
- Works with All Microcontrollers: Pairs perfectly with Arduino, ESP32, Raspberry Pi Pico, STM32, and any platform with an analog input or ADC.
Perfect For
- Automatic Street Light: Build a circuit that turns on an LED or relay-controlled lamp at dusk and off at dawn - a classic embedded systems project.
- Smart Plant Monitor: Measure sunlight exposure for indoor plants and alert via buzzer or app when light levels are too low.
- Line-Following Robot: Use multiple LDRs to detect contrast between a dark line and a light surface for basic robot navigation.
- Light-Level Data Logger: Record ambient brightness over 24 hours using Arduino + SD card module for environmental studies.
- Security Alarm: Detect
How It Works
An LDR is made from cadmium sulfide (CdS), a semiconductor material whose electrical resistance changes with light exposure. When photons strike the CdS surface, they free electrons, increasing conductivity and lowering resistance. In darkness, fewer electrons are free, so resistance climbs to over 1 MOhm. By placing the LDR in a voltage divider circuit with a fixed resistor, you can convert this resistance change into a measurable voltage that a microcontroller's analog-to-digital converter (ADC) can read - giving you a numerical light level in your code.
Basic Wiring Guide
- Voltage Divider (most common): Connect one LDR lead to VCC (3.3V or 5V), the other lead to a 10 kOhm fixed resistor going to GND. Read the voltage at the junction (middle node) using an analog input pin on your microcontroller.
- With Arduino: LDR -> A0 analog pin via voltage divider. Use
analogRead(A0)to get values from 0 (dark) to 1023 (bright light). - With ESP32: Same voltage divider to any ADC-capable GPIO. Use 3.3V supply for accurate 12-bit ADC readings (0-4095).
- Standalone Trigger: Pair with a transistor or comparator (e.g., LM393) to create a simple light-activated switch without a microcontroller.
- Tip: Adjust the fixed resistor value (1 kOhm-100 kOhm) to shift the sensitivity range to match your target lighting conditions.
Frequently Asked Questions
Is technical support available?
Yes, responsive support via email and WhatsApp for setup, troubleshooting, and application guidance.
Are bulk discounts available?
Yes, wholesale pricing on orders of 10+ units. Contact us via WhatsApp or email for a custom quote.
Customer Support
Email: techdepotindia@gmail.com
WhatsApp: Available for setup and troubleshooting help
Order your 5mm LDR (Light Dependent Resistor) today and start building your next project.
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