How to Use IR sensor: Examples, Pinouts, and Specs

An IR (Infrared) sensor is an electronic device that detects infrared radiation emitted by objects. It is widely used in applications such as proximity sensing, motion detection, and remote control systems. IR sensors are versatile and can be found in devices like automatic doors, obstacle-avoiding robots, and TV remote controls. They are valued for their ability to detect objects without physical contact.

• Operating Voltage: 3.3V to 5V DC
• Current Consumption: 20mA (typical)
• Detection Range: 2cm to 30cm (varies by model)
• Output Type: Digital (High/Low) or Analog (depending on the model)
• Wavelength: 700nm to 1mm (infrared spectrum)
• Response Time: < 2ms

*Note: Some IR sensors may not have an analog output pin. Check your specific model for details.

1. Power the Sensor: Connect the VCC pin to a 3.3V or 5V power source and the GND pin to the ground.
2. Connect the Output:
   • For digital output, connect the OUT pin to a digital input pin of your microcontroller.
   • For analog output (if available), connect the OUT pin to an analog input pin of your microcontroller.
3. Adjust Sensitivity: If your IR sensor has a potentiometer, adjust it to set the detection range.
4. Test the Sensor: Place an object in front of the sensor and observe the output signal.

• Ambient Light: IR sensors can be affected by ambient light. Use them in controlled lighting conditions for better accuracy.
• Reflective Surfaces: Highly reflective surfaces may cause false readings. Test the sensor with the intended materials.
• Power Supply: Ensure a stable power supply to avoid erratic behavior.
• Distance Limitations: The detection range is limited. For longer distances, consider using specialized IR modules.

Below is an example of how to use a digital IR sensor with an Arduino UNO to detect an object:

// IR Sensor Example with Arduino UNO
// This code reads the digital output of the IR sensor and turns on an LED
// when an object is detected.

const int irSensorPin = 2;  // IR sensor digital output connected to pin 2
const int ledPin = 13;      // Built-in LED on Arduino UNO

void setup() {
  pinMode(irSensorPin, INPUT);  // Set IR sensor pin as input
  pinMode(ledPin, OUTPUT);      // Set LED pin as output
  Serial.begin(9600);          // Initialize serial communication
}

void loop() {
  int sensorValue = digitalRead(irSensorPin);  // Read the IR sensor output

  if (sensorValue == LOW) {  // Object detected (LOW signal from sensor)
    digitalWrite(ledPin, HIGH);  // Turn on the LED
    Serial.println("Object detected!");
  } else {
    digitalWrite(ledPin, LOW);   // Turn off the LED
    Serial.println("No object detected.");
  }

  delay(100);  // Small delay for stability
}

1. The sensor is not detecting objects.

   • Ensure the sensor is powered correctly (check VCC and GND connections).
   • Verify that the object is within the detection range.
   • Adjust the sensitivity using the potentiometer (if available).

2. False detections or erratic behavior.

   • Reduce ambient light interference by shielding the sensor.
   • Check for reflective surfaces that may cause false readings.
   • Ensure a stable power supply to the sensor.

3. Analog output is not working.

   • Confirm that your sensor model supports analog output.
   • Check the connection to the analog input pin of your microcontroller.

• Can the IR sensor detect transparent objects?
  Transparent objects like glass may not be detected effectively due to low IR reflection.

• What is the maximum detection range of an IR sensor?
  The range varies by model but is typically between 2cm and 30cm.

• Can I use an IR sensor outdoors?
  Yes, but performance may be affected by sunlight or other IR sources. Use an IR sensor with ambient light filtering for better results.

By following this documentation, you can effectively integrate an IR sensor into your projects for reliable object detection and proximity sensing.