User manual

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 0V Ground

If you are sourcing a ultrasonic ranging module , the HC-SR04 is good choose . Its stable

performance and high ranging accuracy make it a popular module in electronic market .

Compared to the Shap IR ranging module , HC-SR04 is more inexpensive than it . But it has the

same ranging accuracy and longer ranging distance.

Specifications:

 power supply :5V DC

 quiescent current : <2mA

 effectual angle: <15°

 ranging distance : 2cm – 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 , and based on the different distance,it will take the different duration of high level. So

we can calculated the distance easily :

Distance = ((Duration of high level)*(Sonic :340m/s))/2

finally , look at the back of the module .All of the chip in the module have been burnish , maybe

the author want to prevent the designed from plagiarism. But ultrasonic ranging module is nearly

the same principle, so it's not hard to speculated that the role of the chip — I'm sure at least one

74series chip on it ; ) . It is not a difficult task to crack it , but … it's at so low a price , even

cheaper than your copy.

Connect your circuit as the below diagram.