Dusk to Dawn Light Detection Sensor Module for Home Automation
Light Detection and Switching Sensor Module – Dusk to Dawn
This sensor module uses an LDR (light-dependent resistor) and an LM393 comparator to detect ambient light levels. It provides a clean digital output that switches state when light crosses a user-adjustable threshold, making it ideal for automating lights based on day/night conditions. The board also exposes the analog LDR reading for more nuanced control.
Key Specifications
| Specification | Value |
|---|---|
| Operating Voltage | 3.3V – 5V DC |
| Comparator IC | LM393 |
| Output Type | Digital (DO) and Analog (AO) |
| Adjustable Sensitivity | Via onboard potentiometer |
| Dimensions | 32mm x 14mm |
| Mounting Holes | 3mm diameter, two holes |
What You Can Build With This
- Automatic porch or garden light that turns on at dusk
- Energy-saving corridor lighting for apartment blocks
- Sunlight alarm that triggers when dawn breaks
- Smart greenhouse shade controller based on light intensity
Compatibility
Works directly with any 3.3V or 5V microcontroller board, including Arduino Uno, Nano, ESP8266, and ESP32. The digital output is TTL-compatible, so no level shifting is required for Raspberry Pi GPIO when using 3.3V supply. Commonly paired with a relay module for switching mains-powered lights.
Wiring Notes
Connect VCC to 5V (or 3.3V), GND to GND, and DO to a digital input pin. The onboard potentiometer sets the light threshold—turn clockwise to require more light for the output to go high. The AO pin provides an analog voltage proportional to light intensity; connect to an ADC input for exact readings. No pull-up resistor is needed on the digital output.
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 Uno?
Yes, it works directly with Arduino Uno. Supply 5V and connect the digital output to any I/O pin; read the state with digitalRead().
How do I adjust the light threshold?
Use a small screwdriver on the blue potentiometer. Turn clockwise to increase the light level needed to trigger, or counterclockwise to make it more sensitive to darkness.
Can this module directly drive a relay?
No, the output current is limited. Use a relay module with a driver transistor or an optocoupler for safe switching of higher loads.
📦 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