LM35 with arduino

1. LM 35
TEMPERATURE SENSOR

2. Pin configuration

3. •LM35 is a basic temperature
sensor that can be used for
experimental purpose .
•It give the readings in centigrade
since its output voltage is linearly
proportional to temperature.
•For 10mv there will be 1 degree
change in temperature.

4. Principle of working
• A temperature sensor measures the
hotness or coolness of an object.
• The sensor's working base is the voltage
that's read across the diode.
• The temperature rises whenever the
voltage increases.
• The operating temperature range is from -
55°C to 150°C.

5. Connecting to arduino

6. code
int val;
int tempPin = 1;
void setup()
{
Serial.begin(9600);
}
void loop()
{
val = analogRead(tempPin);
float mv = ( val/1024.0)*5000;
float cel = mv/10;
Serial.print("TEMPRATURE = ");
Serial.print(cel);
Serial.print("*C");
Serial.println();
delay(1000);
}

7. • 10 bit resolution=>2^10 divisions
5000mv=1024steps
?(x mv)=reading
x mv=5000*reading/1024
10mv=1 degree C change in temp
Temp=x mv/10

9. Serial monitor output

10. Queries?