HC-SR04 Ultrasonic Sensor | Distance Measuring Sensor Module

The HC-SR04 Ultrasonic Sensor measures distance by sending 40000Hz ultrasonic pulses (sound waves too high-pitched for humans to hear) and timing how long the echo takes to return. The hc sro4 ultrasonic sensor runs on 5V DC at just 2mA average current and reaches a maximum sensing distance of 450cm. It connects through four pins on any Arduino or ESP32 board without any additional components.

The ultrasonic sensor hc sr04 has a sensing angle of only up to 15 degrees. One non-obvious detail — objects outside that narrow cone do not return a reliable echo, so the sensor misses targets placed off-axis at longer distances. The honest limitation is soft surfaces. Foam and fabric absorb ultrasonic energy and return weak echoes, giving incorrect readings beyond 100cm. The ultrasonic sensor hc sr04 range works with Arduino IDE, PlatformIO, and MicroPython. Students and hobbyists building robots and distance monitors use it daily. To start, connect TRIG to a digital output pin and ECHO to a digital input pin. StemVolt provides the sensors tested for confirmed echo response across the range.

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Features:

• Maximum sensing distance at 450cm covers room-scale distance measurement from a single fixed mount
• Operating voltage at 5V DC connects directly to Arduino and ESP32 without any additional regulator
• Average current consumption at 2mA allows continuous operation without straining a 5V power pin
• ultrasonic sensor datasheet confirms sensing angle up to 15 degrees for focused forward detection only