HC-SR04 Distance Sensor /Ultrasound proximity
HC-SR04 Ultrasonic Distance Sensor is a popular and low cost solution for non-contact distance measurement function. It is able to measure distances from 2cm to 400cm with an accuracy of about 3mm. This module includes ultrasonic transmitter, ultrasonic receiver and its control circuit.
HC-SR04 module has 4 pins :
- VCC – 5V, +ive of the power supply
- TRIG – Trigger Pin
- ECHO – Echo Pin
- GND – -ive of the power supply
TRIG and ECHO pins can be used to interface this module with a microcontroller unit. These are TTL (0 – 5V) input output pins.