The Rain Drop Moisture Detection Sensor Module is a simple, low-cost module designed to detect water drops, rainfall, or surface moisture in Arduino and other microcontroller projects. 🔹 Components: Rain Sensor Board (Detection Plate) A PCB with exposed copper traces. When water/moisture falls on it, conductivity between the traces increases. Control Module (Signal Processing Board) LM393 comparator IC. Potentiometer for sensitivity adjustment. Provides analog output (AO) and digital output (DO) pins. 🔹 Working Principle: In dry conditions → the sensor board has high resistance → low conductivity → output signal changes. When water/moisture touches the sensor → resistance decreases, conductivity increases → output signal changes. The control module converts this into digital (0/1) or analog (variable voltage) output. 🔹 Pin Configuration: VCC → +3.3V to +5V power supply GND → Ground DO (Digital Output) → HIGH/LOW signal depending on threshold (set by potentiometer) AO (Analog Output) → Variable voltage proportional to water/moisture level 🔹 Applications: Rain detection system for smart homes or weather stations Automatic wiper systems for vehicles Greenhouse and plant watering systems Moisture monitoring in industrial processes IoT-based smart irrigation projects 🔹 How to Use with Arduino: Connect VCC → 5V, GND → GND. Connect AO to Arduino’s analog pin (e.g., A0) for moisture level readings. Connect DO to Arduino’s digital pin (e.g., D2) for simple rain/no-rain detection. Use Arduino code to read sensor values and trigger outputs like LEDs, buzzers, or motors (pumps).