LDR Light Sensor Module with Day/Night Invert Logic

LDR Photosensitive Light Sensor Module (LM393 Comparator)

The LDR Light Sensor Module is a simple yet versatile solution for detecting ambient light levels in electronic projects. It combines a high-sensitivity Light Dependent Resistor (LDR) with an LM393 voltage comparator to provide both analog and digital light detection. This makes the module suitable for applications that require either precise light intensity measurement or simple day/night switching.

The onboard comparator circuit allows users to set a custom light threshold using the adjustable potentiometer. When the surrounding light intensity falls below (or rises above) this threshold, the digital output (D0) changes state, making it ideal for automatic lighting, security systems, and smart sensing applications. The module also provides an analog output (A0) for continuous light level monitoring.

🔧 Key Features

• Photosensitive Element: High-sensitivity LDR (Photoresistor) for ambient light detection.
• Comparator IC:LM393 dual differential comparator for stable and reliable switching.
• Dual Output: Provides both Analog (A0) and Digital (D0) outputs.
• Adjustable Sensitivity: Onboard potentiometer to fine-tune the light detection threshold.
• Day/Night Logic: Digital output typically goes LOW in darkness (invert logic supported).
• Status Indicators: Includes Power LED and Digital Output LED for easy debugging.

💡 Applications

• Automatic Street Lights and smart outdoor lighting systems.
• Day/Night Detection for home automation projects.
• Security and Alarm Systems triggered by light changes.
• Line-Following and Obstacle Detection Robots.
• Educational and DIY Electronics light-sensing experiments.

⚙️ Technical Specifications

📦 Package Includes

• 1 × LDR Light Sensor Module with LM393 Comparator