Lesson 16 Use a thermistor to measure the temperature

Overview

In this lesson, we will learn how to use a thermistor to collect temperature by programming Arduino. The information which a thermistor collects temperature is displayed on the LCD1602.

Requirement

- 1* Arduino MEGA 2560

- 1* USB Cable

- 1* LCD1602

- 1* 10KΩ Potentiometer

- 1* 10KΩ Resistor

- 1* Thermistor

- 1* Breadboard

- Several Jumper Wires

Principle

A thermistor is a type of resistor whose resistance varies significantly with temperature, more so than in standard resistors. We are using MF52 NTC thermistor type. BTC thermistor is usually used as a temperature sensor.

MF52 thermistor key parameters:

B-parameter：3470.

25℃ resistor：10KΩ.

The relationship between the resistance of thermistor and temperature is as follows:

 : The resistance of thermistor at temperature T1

R: The nominal resistance of thermistor at room temperature T2;

e: 2.718281828459；

B: It is one of the important parameters of thermistor;

T1: The Kelvin temperature that you want to measure.

T2: At the condition of room temperature 25 ℃ (298.15K), the standard resistance of MF52 thermistor is 10K;

Kelvin temperature = 273.15 (absolute temperature) + degrees Celsius;

After transforming the above equation, we can get to the following formula:

Procedures

1. Build the circuit

2. Program

_16_thermistor.ino

3. Compile the program and upload to Arduino MEGA 2560 board

Now, you can see the temperature which is collected by thermistor on the LCD1602.

Summary

By learning this lesson, I believe you have learned to use a thermistor to measure temperature. Next, you can use a thermistor to produce some interesting applications.