The HC-SR04 Ultrasonic Sensor measures object proximity between 2cm and 400cm using 40kHz acoustic pulses. It utilizes a 4-pin interface for direct integration with Arduino and Raspberry Pi microcontrollers. This updated version supports a wider 3.3V to 5V input range, removing the need for voltage dividers on 3.3V logic boards.
Key Features
- Detection Range: 2cm to 400cm non-contact measurement capability. Standard distance tracking for obstacle avoidance robots.
- Ranging Accuracy: 3mm precision under optimal environmental conditions. Maintains tight tolerances for automated liquid level sensing.
- Operating Voltage: Wide 3.3V to 5V DC input range. Powers directly from ESP32 or Arduino power rails.
- Ultrasonic Frequency: 40kHz transducer output with 15-degree measuring angle. Pinpoints objects without interference from ambient road dust.
- Low Current Draw: Quiescent current remains under 2mA during operation. Reduces power drain in battery-operated IoT sensors.
Frequently Asked Questions
How to use HC-SR04 with Arduino?
Connect VCC to 5V, GND to ground, and Trig/Echo to digital pins. Trigger a 10µs TTL pulse to initiate the distance calculation.
What is the maximum range of HC-SR04?
The sensor detects objects up to 400cm away. Signal reliability drops significantly beyond this physical limit.