At the heart of the circuit is a PIR sensor module SB0061. SB0061 is a pyroelectric sensor module which developed for human body detection. A PIR detector combined with a fresnel lens are mounted on a ...

It was observed that most hobbyists don’t know about the “LDR” option in HC-SR501 PIR motion sensor module. That’s why I started my ... Just after the failure, I leaped into the circuit diagram of ...

The PIR sensor is kept external to the enclosure and wired up into the tree itself. This allows the sensor to still detect motion in the room while the rest of the circuit is hidden away. [via Reddit] ...

As an example, [Circuit Valley] has an IKEA Vallhorn motion sensor for a teardown, it’s as you might expect, a passive infrared sensor (PIR) sensor coupled with a Zigbee interface.