HC-SR04 Ultrasonic Sensor Distance Measuring Module Ultra01+

The HC-SR04 is a widely used ultrasonic distance sensor that provides non-contact measurement from 2 cm to 450 cm with up to 3 mm resolution. It uses a 40 kHz ultrasonic transducer pair — one transmitter and one receiver — to calculate distance based on the time-of-flight of a sound pulse.

With a simple 4-pin interface (VCC, Trig, Echo, GND), it is straightforward to integrate with Arduino, Raspberry Pi, and other microcontrollers. Send a 10 µs trigger pulse and measure the duration of the echo return to calculate distance.

Key Features

• 2–450 cm Range – Non-contact ultrasonic distance measurement
• 3 mm Resolution – Accurate enough for most robotics and proximity applications
• 15° Effective Angle – Focused detection beam
• Simple 4-Pin Interface – VCC, Trig, Echo, GND
• Low Power – 2 mA quiescent current at 5 V

How It Works

• Apply a 10 µs high pulse to the Trig pin
• The module sends eight 40 kHz ultrasonic pulses
• The Echo pin goes high for the duration of the round-trip time
• Distance = (Echo pulse duration × 340 m/s) ÷ 2

Specifications

• Operating Voltage – 5 V DC
• Quiescent Current – 2 mA
• Measuring Range – 2–450 cm
• Resolution – 0.3 cm
• Effective Angle – 15°
• Trigger Pulse – 10 µs minimum
• Operating Frequency – 40 kHz

Pin Definition

• Pin 1 – VCC (5 V)
• Pin 2 – Trig (trigger pulse input)
• Pin 3 – Echo (echo pulse output)
• Pin 4 – GND

Ideal For

• Robotics obstacle avoidance
• Arduino and Raspberry Pi distance measurement projects
• Liquid level detection
• Proximity sensing and object detection

Package Contents

• 1× HC-SR04 Ultrasonic Sensor Module