Interfacing Analog Temperature Sensor Module with Arduino

Interfacing Analog Temperature Sensor Module with Arduino

Analog Temperature Sensor Module

An Analog Temperature Sensor Module is a device that detects temperature changes and provides an analog voltage output corresponding to the temperature. It is commonly used in weather monitoring, industrial applications, and smart home automation for accurate temperature readings.

Working Principle of Analog Temperature Sensor

The Analog Temperature Sensor Module operates by producing a voltage that is proportional to the surrounding temperature. The sensor's output can be read using an Arduino’s analog input pin, and the temperature value is calculated using a predefined conversion formula.

Wiring the Analog Temperature Sensor to Arduino

To connect the Analog Temperature Sensor Module to Arduino, connect the VCC and GND pins to +5V and GND on the Arduino. The output pin should be connected to an analog input pin (A0) to read temperature values.

Types of Analog Temperature Sensors

LM35 Temperature Sensor

  • Produces an analog voltage proportional to temperature.
  • Requires a simple calibration for accurate readings.
  • Operates within a wide temperature range.

NTC Thermistor

  • Forms a voltage divider circuit with a fixed resistor.
  • Uses resistance change to determine temperature.
  • Requires calibration for precise measurement.

Pin Configuration of Analog Temperature Sensor

LM35 Temperature Sensor

  • VCC: Connect to +5V on Arduino.
  • GND: Connect to GND on Arduino.
  • OUT: Connect to an analog input pin (A0).

NTC Thermistor

  • One Terminal: Connect to +5V on Arduino.
  • Other Terminal: Connect to a voltage divider circuit and then to an analog input pin (A0).

Algorithm

  1. Initialize Components

    • Connect the VCC and GND pins of the temperature sensor to +5V and GND on the Arduino.
    • Connect the OUT pin to an analog input pin (A0) on the Arduino.

  2. Write the Code

    • Set the sensor pin as an analog input in the setup() function.
    • Read the sensor's analog values in the loop() function.
    • Convert the voltage reading into temperature using the appropriate formula.

  3. Display Values or Control Devices

    • Print the temperature readings to the serial monitor.
    • Use the readings to control devices such as cooling fans or heating elements.

  4. Test the Project

    • Upload the code to the Arduino.
    • Test the sensor by exposing it to different temperatures and observing the readings.

Arduino Code

1// Analog Temperature Sensor (LM35) Interfacing Code
2
3const int tempPin = A0;  // Analog input pin where sensor is connected
4
5void setup() {
6  Serial.begin(9600);  // Initialize serial communication
7  Serial.println("Analog Temperature Sensor Initialized");
8}
9
10void loop() {
11  int sensorValue = analogRead(tempPin);  // Read analog voltage (0-1023)
12  
13  // Convert to voltage (assuming 5V ADC reference)
14  float voltage = sensorValue * (5.0 / 1023.0);
15  
16  // LM35 gives 10mV per °C. So, Temp = Voltage * 100
17  float temperatureC = voltage * 100;
18
19  // Optional: Convert to Fahrenheit
20  float temperatureF = (temperatureC * 9.0 / 5.0) + 32;
21
22  // Print results
23  Serial.print("Temperature: ");
24  Serial.print(temperatureC);
25  Serial.print(" °C / ");
26  Serial.print(temperatureF);
27  Serial.println(" °F");
28
29  delay(1000);  // Wait 1 second before next reading
30}
31

Applications

  • Weather monitoring systems
  • Industrial temperature control
  • Smart home automation
  • HVAC systems
  • Agricultural climate control
  • Biomedical temperature sensing

Conclusion

Interfacing an Analog Temperature Sensor Module with Arduino allows you to monitor temperature variations accurately. These sensors are widely used in climate control, industrial automation, and DIY electronics projects. With simple wiring and coding, you can integrate temperature sensing into your applications with ease.