The HC-SR04 is a high-precision ultrasonic sensor that measures distances from 2cm to 400cm using sound wave reflection. Ideal for obstacle detection, robotics, and automation, it offers non-contact measurement with 2mm accuracy.
Key Benefits
✔ High Accuracy – ±2mm precision (at close range)
✔ Wide Range – 2cm to 4m detection
✔ Easy to Use – Simple trigger-pulse interface
✔ Low Cost – Budget-friendly for DIY projects
Technical Specifications
Core Specifications
Operating Voltage: 5V DC
Current Draw: 15mA (typical)
Ultrasonic Frequency: 40kHz
Measurement Angle: 15° cone
Resolution: 0.3cm
Interface & Timing
Trigger Input: 10μs TTL pulse
Echo Output: TTL pulse (width = distance)
Response Time: <20ms
Pins: VCC, GND, Trig, Echo
Physical Properties
Dimensions: 45mm × 20mm × 15mm
Transducers: 1 transmitter + 1 receiver
Mounting: 2x M2 screw holes
Why Choose the HC-SR04?
✔ Plug-and-Play – Works with Arduino/RPi/ESP
✔ No Calibration Needed – Consistent results
✔ Wide Compatibility – Libraries available for all platforms
Common Uses:
Robot obstacle avoidance
Parking sensors
Liquid level measurement
Pro Tip:
For better accuracy, avoid measuring soft/angled surfaces.
Use pulseIn() in Arduino for easy distance calculation.
Package Includes:
1 x HC-SR04 Ultrasonic Sensor Module