Arduino Temperature Measurement

Definition

A temperature is an objective comparative measure of hot or cold. It is measured by a thermometer, Several scales and units exist for measuring temperature, the most common being Celsius (denoted °C; formerly called centigrade), Fahrenheit (denoted °F), and, especially in science, Kelvin (denoted K).

LM35 Temperature Sensor

The LM35 series are precision integrated-circuit temperature sensors, whose output voltage is linearly proportional to the Celsius (Centigrade) temperature.

Components Used
1. LM35
2. Arduino Uno
3. Connecting Wires
Sensor Output:
Sensor gives linear + 10.0 mV/°C scale factor, as per that we have set the calibration in program
Vref=5V
ADC Count for 1°C = 10m/(5/1024) = 2.048
Temperature=ADC Count/2.048

Arduino Circuit for Temperature measurement

LM35 Temperature Sensor Arduino — LM35 Temperature Circuit

Arduino Code for Temperature measurement

/*
  Temperature Measurement - www.circuits4you.com
  Reads an analog input on pin 0, converts it to Temperature, and prints the 
  result to the serial monitor.
  Graphical representation is available using serial plotter 
  (Tools > Serial Plotter menu)
  Attach the LM35 Temperature Sensor as shown in Circuit.
*/

// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}

// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin 0, we have connected LM35 Output
  int sensorValue = analogRead(A0);
  
  // Convert the analog reading (which goes from 0 - 1023) to a Temperature:
  float Temperature = sensorValue / 2.048;
  
  // print out the value you read:
  Serial.print("Temperature:");
  Serial.println(Temperature);
  delay(1000);
}

Results

Open the Serial Monitor from (Tools>>Serial Monitor), you will see the temperature in serial monitor. There is another sensor called DHT11 which can be used for measurement of both temperature and humidity in single package.