HC-SR04 HCSR04 to world Ultrasonic Wave Detector Ranging Module Case Support HC-SR04 HCSR04 Distance Sensor for arduino diy kit : This module has stable performance and accurate measurement distance. Module high-precision, blind (2cm) ultra-close, stable range is the success of this product to the market a strong basis This module fully humility GH-311 anti-theft module. (1) using IO trigger ranging,to at least 10us of high-level signal; (2) the module automatically sends eight 40khz square wave, automatically detect whether there is signal return; (3) there is a signal return, through the IO output of a high, high duration is the time from the launch to the return of ultrasound. Test distance = (high time * sound speed (340M / S)) / 2; This product is simple to use, a control mouth made a 10US above the high level, you can wait for the reception of high-level output. An output can be opened timer, when the mouth becomes low when you can read The value of the timer, this time for the distance of time, can be calculated from the distance. Such a continuous cycle of measurement, you can move the measured value Features: 1: Working voltage: DC5V 2: Quiescent current: less than 2mA 3: Level output: High 5V 4: Level output: Bottom 0V 5: Sensing angle: not more than 15 degrees 6: Detection range: 2cm-450cm 7: High precision: up to 0.3cm