[ladyada] has a freshly-published and amazingly thorough tutorial on passive infrared (PIR) motion sensors. Most often seen in security floodlights and automatic doors, in creative hands these sensors ...

This is an Infrared beam breaking alarm ideal to use in entry or passages.It is based on the working of the popular IR sensor Module TSOP 1738 which senses 38 kHz Infrared pulses from the IR LED of ...

STMicroelectronics is launching a human-presence and -motion detector to enhance security systems, home-automation equipment, and IoT devices that typically use passive infrared (PIR) sensing. The ...