Part Number: HC-SR04
Function: Ultrasonic Ranging Module
Dimension : 45*20*15mm
Manufacturer: Cytron Technologies, ELECFreaks
The HC-SR04 is an ultrasonic ranging sensor that uses sonar technology to detect objects and measure distances. It consists of a transmitter and a receiver that emit and receive ultrasonic waves, respectively. The time taken for the waves to travel to an object and back is used to calculate the distance to the object.
Ultrasonic ranging module HC – SR04 provides 2cm – 400cm non-contact measurement function, the ranging accuracy can reach to 3mm. The modules includes ultrasonic transmitters, receiver and control circuit.
The basic principle of work :
(1) Using IO trigger for at least 10us high level signal,
(2) The Module automatically sends eight 40 kHz and detect whether there is a pulse signal back.
(3) IF the signal back, through high level , time of high output IO duration is the time from sending ultrasonic to returning. Test distance = (high level time×velocity of sound (340M/S) / 2,
Wire connecting direct as following :
1. 5V Supply
2. Trigger Pulse Input
3. Echo Pulse Output
4. 0V Ground
The module is not suggested to connect directly to electric, if connected electric, the GND terminal should be connected the module first, otherwise, it will affect the normal work of the module.
When tested objects, the range of area is not less than 0.5 square meters and the plane requests as smooth as possible, otherwise ,it will affect the results of measuring.