HC-SR501 PIR Sensor (Passive Infrared Sensor) + IR Proximity Sensor Documentation

Pin Configuration

HC-SR501 PIR Sensor (Passive Infrared Sensor) + IR Proximity Sensor Documentation
Pin Description:
The HC-SR501 PIR Sensor module has 3 pins for connection. Here's a detailed explanation of each pin:
VCC (Pin 1):
+ Function: Power Supply
+ Description: This pin is used to connect the positive voltage supply to the module. Typically, a voltage range of 4.5V to 20V can be used, but the recommended operating voltage is 5V.
+ Connection: Connect to the positive terminal of the power source (e.g., a 5V pin on an Arduino board).
OUT (Pin 2):
+ Function: Digital Output
+ Description: This pin outputs a digital signal ( HIGH or LOW ) when the sensor detects motion or proximity. The output is an open-drain output, which means it can sink current but not source it.
+ Connection: Connect to a digital input pin on a microcontroller (e.g., an Arduino board) to read the sensor's output.
GND (Pin 3):
+ Function: Ground
+ Description: This pin is used to connect the ground reference of the module to the system.
+ Connection: Connect to the negative terminal of the power source (e.g., a GND pin on an Arduino board).
Connection Structure:
Here's a step-by-step guide to connect the HC-SR501 PIR Sensor module:
1. Power Connection:
Connect the VCC pin (Pin 1) to the positive terminal of the power source (e.g., 5V pin on an Arduino board).
Connect the GND pin (Pin 3) to the negative terminal of the power source (e.g., GND pin on an Arduino board).
2. Signal Connection:
Connect the OUT pin (Pin 2) to a digital input pin on a microcontroller (e.g., Arduino Uno's digital pin 2).
Important Notes:
The HC-SR501 PIR Sensor module has a built-in voltage regulator, so it can operate with a wide range of input voltages. However, it's recommended to use a stable 5V power supply for optimal performance.
The sensor module has a sensitivity adjustment potentiometer on the back, which can be used to adjust the detection range.
The module also has a time delay adjustment potentiometer on the back, which can be used to adjust the time delay between consecutive trigger events.
By following these instructions, you can properly connect the HC-SR501 PIR Sensor module to your project and start detecting motion and proximity.

Code Examples

HC-SR501 PIR Sensor (Passive Infrared Sensor) + IR Proximity Sensor Documentation

Overview

The HC-SR501 PIR Sensor is a low-power, low-cost sensor that detects infrared radiation, typically emitted by humans. It is widely used in various applications, including security systems, home automation, and robotics. This sensor combines a passive infrared (PIR) sensor with an infrared (IR) proximity sensor, allowing it to detect both motion and proximity.

Pinout and Connections

The HC-SR501 PIR Sensor has three pins:

VCC (Red wire): Connect to a 5V power supply
 GND (Black wire): Connect to the ground (GND) of the circuit
 OUT (Yellow wire): Connect to a digital input pin of a microcontroller or other device

Specifications

Operating voltage: 5V
 Current consumption: 65mA
 Detection range: Up to 7 meters (23 feet)
 Detection angle: 120
 Response time: 0.5 seconds

Code Examples

### Example 1: Basic Motion Detection using Arduino

This example demonstrates how to use the HC-SR501 PIR Sensor with an Arduino board to detect motion and toggle an LED.

```cpp
const int pirPin = 2;  // Define the PIR sensor pin
const int ledPin = 13;  // Define the LED pin

void setup() {
  pinMode(pirPin, INPUT);  // Set the PIR sensor pin as an input
  pinMode(ledPin, OUTPUT);  // Set the LED pin as an output
}

void loop() {
  int sensorState = digitalRead(pirPin);  // Read the PIR sensor state

if (sensorState == HIGH) {
    digitalWrite(ledPin, HIGH);  // Turn on the LED if motion is detected
  } else {
    digitalWrite(ledPin, LOW);  // Turn off the LED if no motion is detected
  }
  delay(100);
}
```

### Example 2: Proximity Detection using Raspberry Pi (Python)

This example demonstrates how to use the HC-SR501 PIR Sensor with a Raspberry Pi to detect proximity and print a message to the console.

```python
import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM)  # Set the GPIO mode to BCM

pirPin = 17  # Define the PIR sensor pin

GPIO.setup(pirPin, GPIO.IN)  # Set the PIR sensor pin as an input

while True:
    if GPIO.input(pirPin) == GPIO.HIGH:
        print("Object detected!")
    else:
        print("No object detected")
    time.sleep(0.5)  # Wait for 0.5 seconds before checking again
```

Note: Make sure to connect the HC-SR501 PIR Sensor to the appropriate pins on your microcontroller or single-board computer, and adjust the code accordingly.