HC-SR04 Ultrasonic Distance Sensor Module

The HC-SR04 module determines the distance to an object by sending an ultrasonic pulse and receiving a delayed reflection. Based on this delay, the device determines the presence of objects and the distance to them. The ultrasonic emitter sends 8 signals at a frequency of 40kHz, which will be reflected by objects and recorded with a microphone in this sensor module.

It can measure from 2 cm to 400 cm with an accuracy of 2 mm. It is an ideal ultrasonic module for distance measurement, proximity sensors, and ultrasonic detectors.

 

Technical Specification:

• Operating Voltage: 5V DC.
  
• Operating Current: Less than 15 mA.
  
• Range: 2 cm to 400 cm (0.79 inches to 13 feet).
  
• Accuracy: Around ±3 mm.
  
• Frequency: 40 kHz.

 Pinouts:

Connection with Arduino:

Module	Arduino UNO
VCC	5V
Trig	Pin 9
Echo	Pin 10
GND	GND

 

Sample Code:

const int trigPin = 9;

const int echoPin = 10;

long duration;

int distance;

 

void setup() {

  pinMode(trigPin, OUTPUT);

  pinMode(echoPin, INPUT);

  Serial.begin(9600);

}

 

void loop() {

  // Send a 10-microsecond pulse to the trigPin

  digitalWrite(trigPin, LOW);

  delayMicroseconds(2);

  digitalWrite(trigPin, HIGH);

  delayMicroseconds(10);

  digitalWrite(trigPin, LOW);

 

  // Read the echoPin and calculate the distance

  duration = pulseIn(echoPin, HIGH);

  distance = duration * 0.0343 / 2;

 

  // Print the distance to the Serial Monitor

  Serial.print("Distance: ");

  Serial.print(distance);

  Serial.println(" cm");

 

  delay(500);

}