Build a Passive Infrared Sensor Circuit

What is PIR ?Passive Infrared Sensor Circuit Diagram. Detectors or pyroelectric sensors, passive infrared or PIR sensor, are made of a crystalline material that generates an electric charge on the surface when exposed to heat in the form of infrared radiation. When radiation increases the amount of electrical charge increases too and this load is measured with a sensitive FET transistor which is inside the sensor module.

With the RIP is commonly used as a motion detector of an object by detecting the infrared signal radiated from the object (people and animals). The Passive Infrared Sensors are also used in remote thermometers.

Pin 1 of the PIR must be connected to the positive supply 5V DC. Pin 2 is the output of PIR sensor, it must have a connection to the earth through a resistor of 47K to 100K (depending on the circuit). Pin 3 of the RIP must be connected to ground or negative circuit.
 

Simple Circuit Diagram using PIR Sensor

Simple circuit motion sensor PIR detector.

Connect the PIR sensor in Arduino

The image above shows a PIR sensor as a switch connected to an Arduino board using a 10k pull-down resistor.