Product Description & Technical Details
Product Description
The HC-SR04 is the industry-standard ultrasonic ranging module, widely used in the maker community and industrial prototyping for non-contact distance measurement. It consists of an ultrasonic transmitter, a receiver, and a control circuit. The module works on the "sonar" principle: it emits an ultrasonic burst at 40kHz; if it hits an object, the sound waves bounce back and are detected by the receiver. By measuring the time interval between sending and receiving the signal, the distance to the target can be calculated with high precision.
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Key Highlights
Stable Range Performance: Provides reliable distance detection from as close as 2cm up to 4 meters, making it perfect for liquid level sensing and robot navigation.
Ease of Integration: Requires only two digital pins (Trigger and Echo) to communicate with any microcontroller, including Arduino, ESP32, and STM32.
High Resolution: Capable of detecting changes in distance as small as 3mm, allowing for precise movement tracking.
Low Power Consumption: Draws less than 2mA during operation, making it suitable for battery-powered portable devices.
Non-Contact Measurement: Ideal for applications where the sensor cannot touch the object, such as measuring the depth of water in a tank or detecting obstacles for a fast-moving robot.
Technical Specifications
Operating Current: 15mA
Ultrasonic Frequency: 40kHz
Dimensions: 45mm x 20mm x 15mm
Connector: 4-pin male header (2.54mm pitch)
Effect of Environment: Accuracy is largely unaffected by sunlight or black material (unlike infrared sensors).
Prototyping & Installation Tip
To calculate the distance in centimetres, use the formula:
The "0.034" represents the speed of sound in cm/µs. When mounting the sensor, ensure there are no large flat surfaces within the 15-degree sensing cone that could cause "false echoes." If using this with a 3.3V microcontroller like an ESP32 or Raspberry Pi, you must use a simple voltage divider on the Echo pin to drop the 5V signal to 3.3V to avoid damaging your board.
Note: This product is the HC-SR04 Sensor Module ONLY. Mounting brackets and jumper wires are sold separately. Product images are for illustration purposes only.