- The ranging accuracy can reach to 3mm.
- The modules includes ultrasonic transmitters, receiver and control circuit.The basic principle of work:
- The Module automatically sends eight 40 kHz and detect whether there is a pulse signal back.
- IF the signal back, through high level , time of high output IO duration is the time from sending ultrasonic to returning.
Distance = ((Duration of high level)*(Sonic :340m/s))/2.Specifiction:
- Power supply :5V DC
- Quiescent current : <2mA
- Effectual angle: <15°
- Ranging distance : 2cm â€?500 cm
- Resolution : 0.3 cm
There are 4 pins out of the module : VCC , Trig, Echo, GND.
So it's a very easy interface for controller to use it ranging.
The all process is :
- Pull the Trig pin to high level for more than 10us impulse
- The module start ranging
- Finish ranging
- If you find an object in front
- Echo pin will be high level
- Based on the different distance,it will take the different duration of high level.
Distance = ((Duration of high level)*(Sonic :340m/s))/2