Ultrasonic Sonar Sensor HC- SR04

HCSR04 is an Ultrasonic ranging module that consists of a transmitter, receiver, and control circuit. It has four pins for VCC, GND, Trigger, and Echo. You can easily interface it with microcontrollers and Arduino boards.

The basic principle of work is:

1. Using IO trigger for at least 10us high-level signal
2. The Module automatically sends eight 40 kHz and detects whether there is the pulse signals back.
3. If the signal is back, through a high level, the time of high output IO duration is the time from sending ultrasonic to returning.
4. Test distance = (high level time×velocity of sound (340M/S) / 2

Specifications

• Working Voltage DC 5 V
• Working Current 15mA
• Working Frequency 40Hz
• Max Range 4m
• Min Range 2cm
• Measuring Angle 15 degree
• Trigger Input Signal 10uS TTL pulse
• Echo Output Signal Input TTL lever signal and the range in proportion
• Dimension 45x20x15mm