Temperature measurement using LM35 and Arduino UNO

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LM35 is a precision temperature integrated circuit which gives an output voltage proportional to the temperature in centigrade. LM35 has three legs out of which two are positive voltage supply and ground. Remaining one is the output which gives an output voltage proportional to temperature in centigrade. Circuit is done as shown in the following diagram.

2 74165 and LDR

Pin out diagram of LM35

Screenshot from 2015-08-04 08:51:04

After completing the circuit, upload the following program to your arduino board. If uploading is successful, open your serial monitor where you can see the temperature in degree celsius.

int value;
int temp_read_pin = 1;

void setup()
{
  Serial.begin(9600);
}
void loop()
{
  value = analogRead(temp_read_pin);
  float mv = ( value/1024.0)*5000; 
  float celsius = mv/10;

  Serial.print("TEMPRATURE IS ");
  Serial.print(celsius);
  Serial.print("*C");
  Serial.println();
  delay(100);
}

Screenshot of serial monitor is given below. Temperature will be printed in the serial monitor.

Screenshot from 2015-07-24 18:14:44

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paulpp644
A deep electronic enthusiast who spent most of my time for electronic experiments. I am also interested in publishing my experiments in my blog for helping other electronics enthusiasts.