Characteristic:

The HC-SR04 ultrasonic distance measuring module provides non-contact distance measuring function from 2cm to 450cm and high distance accuracy up to 3mm. Module consisting of ultrasonic transmitter, receiver and control circuit.

Basic working principle:

1. Use IO mouth TRIG trigger distance, at least 10 high level US signals;

2. The module automatically sends eight 40KHz square waves and automatically detects whether a signal is returned.

3. I returned the signal, through the IO mouth, ECHO output a high level, the duration of the high level is the time of the ultrasonic wave from start to return.

4. Distance = test (high level time * speed of sound (340 m/s)) / 2;

Operating voltage: DC 5V
Operating current: less than 2mA
Working frequency: 40Hz
maximum range: 450CM
Minimum range: 2 CM
Measuring point: 15 degrees
Input trigger signal: 10US TTL pulse
Echo signal output: Output the TTL level signal, proportional to the range.

Document link:
https://www.adrive.com/public/rRKFHV/k000175.rar

Note 1:
The TRIP pin is an internal pull-up resistor of 10K. Use the IO port of the microcontroller to pull the TRIP pin low, and then give a pulse signal of more than 10us. The OUT pin is the switching output pin when this module is used as an anti-theft module. This pin is not used in the ranging module.

Note 2:
The module should be plugged into the circuit board first and then powered on to avoid high-level malfunction. If it occurs, it can be solved by repowering it.

Delivery content:
3 X 4 Pin Ultrasonic Distance Measuring Sensor Module HC-SR04
3 X Mounting Bracket
Female to Female Cable
Male to Female Cable