PIR motion Sensor interface with Atmega128 Revision as of 18:55, 13 April 2016 by Raghavendra (Talk | contribs)
In this tutorial we will see something interesting sensor which tells your presence in the room, automatic door in elevator and shopping malls, automatic lighting system, washroom amenities. Let's see in this tutorial how this sensor basically works?
Basics
This in expensive sensor allow you to sense the motion and it detects the presence of human being or heat emitting body in its proximity. These are named as Pyroelectric sensor or Passive Infrared (PIR) sensor. Pyroelectricity means heat which generates the electricity. PIR sensors are passive sensor, which means they are not generates infrared energy but they detect the heat energy which is given by other heat emitted body in the form of radiation. The sensor is split into two halves, one detects more or less infrared and turned out into high or low signal. Along with Infrared sensor it consist bunch of other circuit. See below images for reference.
The plastic window is covered on infrared sensor which