Datasheet

This is the HC-SR04 ultrasonic distance sensor. This economical sensor provides 20 mm
to 4 m of non-contact measurement functionality with a ranging accuracy that can reach
up to 3mm. Each HC-SR04 module includes an ultrasonic transmitter, a receiver and a
control circuit.
There are only four pins that you need to worry about on the HC-SR04: VCC (Power),
Trig (Trigger), Echo (Receive), and GND (Ground). You will find this sensor very easy to
set up and use for your next range-finding project!
This sensor has additional control circuitry that can prevent inconsistent data depending
on the application.
Features
 Operating Voltage: 5V DC
 Operating Current: 15mA
 Measure Angle: 15°
 Ranging Distance: 2cm - 4m