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PIR Motion Sensor

A standard Passive Infrared sensor for detecting motion of humans or animals.

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PIR Sensor

The PIR (Passive Infrared) motion sensor detects changes in infrared radiation, typically caused by a moving person or animal. When motion is detected, the sensor's output pin goes HIGH.

SensorsDigital InputMotion

Overview

PIR sensors are commonly used in security systems, automatic lighting, and smart home applications. They are easy to interface with microcontrollers as they provide a simple digital signal (HIGH when motion is detected, LOW otherwise).

Pin Reference

Pin	Type	Description
VCC	power	Power supply (5V).
OUT	digital	Digital output (HIGH = motion detected).
GND	power	Ground.

Configurable Attributes

Attribute	Type	Default	Description
delay	number	500	The time (in milliseconds) the OUT pin stays HIGH after motion stops.

Wiring Diagram

1. Connect VCC to 5V.
2. Connect OUT to a digital input pin on the Arduino (e.g., D2).
3. Connect GND to Ground.

Example Arduino Code

This example reads the sensor and turns on the built-in LED (pin 13) when motion is detected.

#define PIR_PIN 2
#define LED_PIN 13

void setup() {
  pinMode(PIR_PIN, INPUT);
  pinMode(LED_PIN, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int motionState = digitalRead(PIR_PIN);
  
  if (motionState == HIGH) {
    digitalWrite(LED_PIN, HIGH);
    Serial.println("Motion detected!");
  } else {
    digitalWrite(LED_PIN, LOW);
  }
  
  delay(100);
}

Simulation Notes

• In the simulator, click on the PIR sensor to reveal its detection cone.
• You can drag the blue dot to simulate movement inside the detection zone.

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