Digital output pin that goes High (3.3V) when motion is detected. Ground connection. Sensitivity Adjustment:
The HW-416B is a cheap ($1.50) clone that works okay , but it is strictly inferior to the original HC-SR501 due to the 3.3V output and longer dead time. If you are building a battery-powered project, skip this. If you are building a bench light switch, it is fine. hw416b pir sensor datasheet better
The PIR modules have a passive infrared sensor that detects the occupancy and movement from the infrared radiated from human body. Tayda Electronics PIR Motion Sensor | Adafruit Digital output pin that goes High (3