This is ultrasonic sensor distance measuring module which a non-contact distance measurement module. It has high measurement accuracy and its blind area is close (up to 2cm).
 

Features:
- Working voltage: 3-5.5VDC
- Static current: less than 2 mA.
- IO logic voltage: 3.3V / 5V.
- Induction angle: not more than 15 degrees.
- Detection range: 2-400 cm.
- Accuracy: 3mm
- Adopt IO trigger through supplying at least 10us sequence of high level signal
- The module automatically send eight 40khz square wave and automatically detect whether receive the returning pulse signal
- If there is signals returning, through outputting high level and the time of high level continuing is the time of that from the ultrasonic transmitting to receiving.