This is a miniature Passive Infrared Motion Detector, just like you would have on security lights except teeny weeny.
Using such a sensor is pretty simple, supply 3.3 to 15v on the + pin, Ground on the – Pin, and then the Out pin will go high at 3.3v when motion is detected.
Sensing distance is up to 5m, 0-3.5m is best
High Signal Output is 3.3v (this will be fine for both 3.3v and 5v arduinos to read as high)
Low Signal Output is 0v
Supply Voltage is 3.3 to 15v
Supply Current is just 20uA
When motion is detected the output pin goes high (3.3v) for 2.5 seconds, then it goes low again for a minimum of 2 seconds blocking time before it will detect motion again.
The two S pins are for connecting a photo diode if you wanted to limit detection to only in the dark.
For the adventurous this video I found shows possibilities for changing a resistor to extend the high time, not something I would recommend myself, I’d just do it in code!
