SKU: SENS-3292
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LM393 Light-Dependent Resistor Sensor Module - Digital/Analog Output

₹29.00 (Inclusive of all taxes)
Out of Stock

The LM393 Light-Dependent Resistor Sensor Module provides both digital and analog outputs for ambient light detection, compatible with 3.3V and 5V microcontroller systems like Arduino and Raspberry Pi. It features an adjustable sensitivity potentiometer and a built-in indicator LED for signal output status.

Features

  • Dual Output: Provides digital (DO) switch signal and analog (AO) voltage output for flexible light intensity measurement.
  • Adjustable Sensitivity: Integrated blue digital potentiometer allows precise threshold calibration for the digital output.
  • Wide Voltage Compatibility: Operates from 3.3V to 5V DC, making it suitable for both 3.3V logic (Raspberry Pi, ESP32) and 5V logic (Arduino) systems.
  • Integrated LM393 Comparator: Ensures clean, stable digital output switching with minimal bounce.
  • Compact & Mountable: Features a 33mm x 14mm PCB with mounting holes for secure installation.

Out of stock

Description

This module utilizes a high-quality LM393 voltage comparator paired with a sensitive photoresistor (LDR) to convert changes in ambient light intensity into a clean digital signal or a proportional analog voltage. The comparator design ensures a Sharp Microelectronics, bounce-free digital output when the light level crosses a user-defined threshold set by the onboard potentiometer.

The analog output provides a continuous voltage signal proportional to light intensity, which can be read by an ADC (Analog-to-Digital Converter) on a microcontroller for more precise light level monitoring. The module includes a status LED that illuminates when the digital output is triggered, providing immediate visual feedback. Its robust design and simple 4-pin interface (VCC, GND, DO, AO) make it ideal for integration into DIY electronics, educational projects, and basic industrial control systems.

Key Features

  • Dual-mode output: Digital TTL-compatible switch and analog voltage signal.
  • Precision-trimmed sensitivity adjustment via a multi-turn potentiometer.
  • High-reliability LM393 comparator IC for stable, noise-immune switching.
  • Broad-spectrum photoresistor for general ambient light detection.
  • Compact PCB with standard 2.54mm pitch pin headers for easy prototyping.
  • Integrated power and signal status indicator LED.
  • Optimized performance-to-cost ratio for educational and hobbyist applications.

Applications

  • Automatic lighting control systems for homes or offices.
  • Daylight harvesting and smart window blind automation.
  • Light-triggered security alarms or intrusion detection systems.
  • Educational kits for teaching photoresistor and comparator fundamentals.
  • Robotics for light-following or obstacle avoidance based on ambient conditions.

Technical Specifications

Model / NameLM393 Light-Dependent Resistor Sensor Module
Operating Voltage3.3V to 5V DC
Output SignalsDigital (DO) & Analog (AO)
Core ICLM393 Voltage Comparator
Sensing ElementLight-Dependent Resistor (LDR)
PCB Dimensions (L x W)33 mm x 14 mm
Module Weight4 g
Interface PinsVCC, GND, DO (Digital Out), AO (Analog Out)
Sensitivity ControlAdjustable via onboard potentiometer
Output IndicatorIntegrated LED

Frequently Asked Questions

What is the difference between the DO and AO pins on this module?

The DO (Digital Output) pin provides a clean TTL-level signal (0V or VCC) that switches based on the light intensity crossing a threshold set by the potentiometer. The AO (Analog Output) pin provides a continuous voltage signal proportional to the light intensity, which can be read by an ADC pin on a microcontroller for precise light level measurement.

What is the operating voltage range, and can I use it with a 3.3V system like ESP32?

Yes, the module is fully compatible with both 3.3V and 5V logic systems. Its operating voltage range is 3.3V to 5V DC. When powered by 3.3V, the digital output will be a 3.3V logic signal, making it safe to connect directly to the GPIO pins of an ESP32 or Raspberry Pi without a level shifter.

How do I adjust the module's sensitivity and what does the LED indicate?

Sensitivity is adjusted by turning the blue multi-turn potentiometer on the board. Rotating it changes the trigger threshold for the digital output. The onboard LED lights up when the digital output is in the active low state (typically under strong light), providing direct visual feedback of the switching condition.

Can this module directly drive a relay or other loads?

The digital output pin can signal a microcontroller or drive the input of a dedicated relay module, but it cannot directly power a relay coil or other significant loads due to current limitations of the LM393 output. For load control, interface the DO pin with a transistor or a relay module designed for microcontroller input.

Package Includes

  • 1 x LM393 Photosensitive Light-Dependent Resistor Sensor Module

Additional Information

Weight 0.004 kg
Dimensions 3.3 × 1.4 cm