This circuit is from the GLOLAB web page. The document referenced here includes an excellent design as well as an excellent tutorial on PIR devices. You've probably seen these ...

PIR LED Security Light Circuit Schematic Notes The PIR sensor requires an initial stabilization time of about 10 to 60 seconds in order to function properly. During this time, the sensor gets familiar ...

By making the sensor surface-mountable, the device now occupies 30% less in volume versus that required by traditional PIR sensors. Height was also reduced to approximately 60% that of its ...

Described security light circuit design is centered around an inexpensive passive infrared (PIR) motion detector module, type HC-SR501. The PIR motion detector module is used here with an added ...