The HC-SR501 is a passive infrared (PIR) motion detection module with adjustable sensitivity and hold time. It outputs a HIGH pulse when motion is detected, with detection range up to 7 meters and 110-degree sensing angle.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | VCC | Power supply 4.5V–20V | PWR |
| 2 | OUT | Output HIGH when motion detected | I/O |
| 3 | GND | Ground | GND |