HC-SR04 ULTRASONIC DISTANCE SENSOR MODULE 

The HC-SR04 Ultrasonic Distance Sensor Module is an electronic measuring device used to detect the distance between the sensor and an object using ultrasonic sound waves. It works by transmitting a high-frequency ultrasonic pulse of approximately 40 kHz and measuring the time taken for the echo to return after reflecting from an object. The distance is calculated based on the speed of sound, providing accurate and reliable measurements. This module is widely used in electronics projects, robotics, automation systems, obstacle detection, parking sensors, and level measurement applications. It is compatible with popular microcontrollers such as Arduino, Raspberry Pi, ESP8266, and ESP32.

WORKING PRINCIPLE

The HC-SR04 operates by sending an ultrasonic pulse through the TRIG pin, which travels through the air until it encounters an object. The sound wave reflects off the object and returns to the sensor, where it is received through the ECHO pin. The controller measures the time difference between the transmitted pulse and the received echo. Using this time value and the known speed of sound, the distance is calculated using the formula Distance = (Time × Speed of Sound) ÷ 2. This method allows accurate, non-contact distance measurement.

TECHNICAL SPECIFICATIONS

The module operates at 5 V DC with an approximate current consumption of 15 mA. It offers a measuring range from 2 cm to 400 cm with a measuring angle of about 15 degrees and operates at an ultrasonic frequency of 40 kHz. The interface includes VCC, Trig, Echo, and GND pins, and the output is provided as a digital pulse signal. These features make the HC-SR04 reliable and easy to integrate into various embedded systems and automation projects.

APPLICATIONS

The HC-SR04 Ultrasonic Distance Sensor Module is ideal for robotics and obstacle avoidance, distance and proximity measurement, liquid level detection, smart parking systems, industrial automation, and educational or DIY electronics projects. Its accuracy, affordability, and ease of use make it a popular choice for both beginners and advanced electronics applications.