Wednesday, May 16, 2012

Simple Labs' Quick Start Kit for Arduino - Sensor Interfacing - LM35 Temperature Sensor- How To?

Working with Sensors - LM35

So lets get started with some sensors, LM35 is a simple temperature sensor. LM35 has 3 pins. Refer to the following image for the pin mappings
This is the LM35 as it looks

The LM35 pin Mapping. Note: The image on the left is a BOTTON view. This is how you will find it in the Product Datasheet 
Place the LM35 as shown

Connect Wires to Supply & Ground. Take a wire from the middle pin and connect it to Analog In 2 of the Arduino
Heres the finished Setup
Now time for the program. Try the following program.  Pressing the Button changes the current active color of the RGB LED & prints the current temperature value to the Serial Monitor and varying the trimpot changes the intensity of the color [RGB_button_lm35.ino]

  Pressing the Button changes the current active color of the RGB LED & prints the current temperature value to the Serial Monitor
  and varying the trimpot changes the intensity of the color


int intensity = 0, pin = 9;

void setup() {      

void loop() {
  if(digitalRead(2)==0) // Switch being pressed
    Serial.print("Temperature is : ");
    int temp = analogRead(2)/2;
  intensity = analogRead(0)/4;
  Serial.print("   ");


  1. Hello, i had bought the Quick start kit, and i don;t exactly know which one is the temp.sensor. there is something which resembles the one shown here, but not exactly. for one thing, it has a small bu;ge on one side, and there appear to be 4 legs out of which one seems to be broke. is it the temp.sensor? also, please note that i did not get any sheet along with my order, so kindly request you to provide one if possible.. thanks!


  2. Dear , plz see one is transistor and another is temp.sensor .

    plz read the last code on printed in that if "DZ" then its temp.sensor another is transistor.

  3. my name is ilyas ahmed i bought the kit and made connections as there but i am not getting output if i click serial monitor then it is continiusly printing the values like 458
    the temp cant be 458 na so ples can u help me

    1. can u send a snapshot of the serial moniter and your project (arduino and breadboard)

  4. Hi. Why do you divide temp sensor reading "analogRead(2)/2" ?