Interfacing LM35 Temperature Sensor With Arduino

Thermometers are useful apparatus being used for a long time for temperature measurement. In this project, we have made an Arduino based digital thermometer to display the current ambient temperature and temperature changes on an LCD. It can be deployed in houses, offices, industries etc. to measure the temperature. This project is based on Arduino which communicates here with an LM35 temperature sensor and a 16x2 display unit. We can divide this Arduino based thermometer into three sections - The first senses the temperature by using temperature sensor LM 35, the second section converts the temperature value into a suitable number in Celsius scale which is done by Arduino, and last part of the system displays the temperature on LCD.

Step 1: Components Used:

Arduino Uno
Breadboard
LCD 16*2
LM35 ( Temperature sensor )
Potentiometer
Resistor (220 ohms)

Step 2: Circuit Diagram:

Circuit diagram for digital thermometer using Arduino LM35 temperature sensor is shown in the above figure. Make the connections carefully as shown in the schematic. Here 16x2 LCD unit is directly connected to Arduino in 4-bit mode. Data pins of LCD namely RS, EN, D4, D5, D6, D7 are connected to Arduino digital pin number 7, 6, 5, 4, 3, 2. A temperature sensor LM35 is also connected to Analog pin A0 of Arduino, which generates 1 degree Celsius temperature on every 10mV output change at its output pin.