The size and price of the ESP wifi modules have quickly made them into one of the preferred building blocks for IoT devices. Unfortunately they are not particularly well suited for very low power ...

Moderately priced Passive Infrared PIR Sensor modules are now widely available. By using these readymade and pre-configured PIR sensors, even an average electronics hobbyist can construct his/her own ...

Let me introduce another simple microcontroller-based do-it-yourself circuit that detects motion and excites a light source in a flash. The “snooper” here is an ordinary passive infrared (PIR) motion ...

Figure 1 shows a way to control a light (or other 120-V ac appliance) with a passive-infrared (PIR) alarm sensor. The original concept was to turn a closet or shop light on whenever someone went into.