LDR Sensor Module - Photosensitive Light Detection Sensor Module
LDR Sensor Module - Photosensitive Light Detection Sensor Module
This LDR (Light Dependent Resistor) sensor module detects ambient light intensity and provides both analog and digital outputs. It uses a photoresistor as the sensing element and an LM393 comparator to generate a clean digital signal based on a user-adjustable threshold. The module is ideal for building light-sensitive switches, automatic lighting systems, and IoT light monitoring projects.
Key Specifications
| Specification | Value |
|---|---|
| Operating Voltage | 3.3V to 5V DC |
| Output Type | Analog (0-5V) and Digital (TTL) |
| Sensitivity Adjustment | Onboard potentiometer |
| Comparator IC | LM393 |
| PCB Size | Approx. 32mm x 14mm |
| Mounting Hole Diameter | 3mm |
What You Can Build With This
- Automatic night lamp that turns on in darkness
- Light intensity meter for classroom or lab experiments
- Laser tripwire alarm system
- Light-following robot or panel tracker
Compatibility
This module works with any microcontroller that supports analog or digital inputs, including Arduino Uno, Nano, and Mega, ESP32, ESP8266, and Raspberry Pi. It operates at 3.3V to 5V, so no level shifting is required for most boards. Commonly paired with relay modules for switching AC loads.
Wiring Notes
Connect VCC to 5V (or 3.3V), GND to ground, AO to an analog pin for continuous light readings, and DO to a digital pin for threshold detection. The onboard red LED lights when the digital output goes low (light exceeds threshold). Adjust the blue potentiometer to set the trip point.
Why Buy from Compoden
Every component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-5 days. If defective on arrival, replace within 7 days.
Is this compatible with Arduino?
Yes, simply connect VCC to 5V, GND to GND, AO to A0, and DO to D2. It requires no special libraries.
How do I adjust the sensitivity?
Use a small screwdriver to turn the onboard potentiometer. Rotating clockwise increases the light level required to trigger the digital output; counterclockwise decreases it.
Can I use both analog and digital outputs at the same time?
Yes, the module provides simultaneous analog and digital outputs, so you can read light intensity while also monitoring a threshold event.
📦 Free Setup Handoff Document Included
Every Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.
Ask Soldr above what you can build with this — it knows every Compoden kit this part appears in.
Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items