This is the HC-SR04 ultrasonic distance sensor. This economical sensor provides 2cm to 400cm of non-contact measurement functionality with a ranging accuracy that can reach up to 3mm. Each HC-SR04 module includes an ultrasonic transmitter, a receiver, and a control circuit.

There are only four pins that you need to worry about on the HC-SR04: VCC (Power), Trig (Trigger), Echo (Receive), and GND (Ground). You will find this sensor very easy to set up and use for your next range-finding project!

This sensor has additional control circuitry that can prevent inconsistent “bouncy” data depending on the application

🛠️ Working Principle:

1. Provide a trigger input by sending a 10μs HIGH pulse to the “Trig” pin.

2. The sensor automatically transmits eight 40kHz ultrasonic pulses.

3. It then waits for the reflected signal (echo).

4. If an echo is received, the “Echo” pin goes HIGH for a duration proportional to the round-trip time of the signal.

5. Measure the pulse width of the Echo pin to calculate distance using the formula:
   Distance (cm) = (Echo pulse time in µs) / 58

For exact technical details and timing diagrams, please refer to the HC-SR04 datasheet.

📦 Package Includes:

• 1 × HC-SR04 Ultrasonic Distance Sensor Module