Design of Temperature Measuring Instrument Using NTC Thermistor of Fe2TiO5 Sensor Based on Microcontroller Atmega 328
Siti Sarah Munifah (a*), Wiendartun (a), Ahmad Aminudin (a)

a) Physics Program, Faculty of Mathematics and Science Education, Universitas Pendidikan Indonesia

Abstract

Thermistor is one of temperature sensor which works based on resistance changes. In a previous study, an NTC thermistor of Fe2TiO5 was made in the form of raw pellet without doping, sintered at a temperature of 1200 \(^{o}\)C for 2 hours in oxygen. A thermistor constant value that obtained from the characterization process is 3642.7 MOhm. This result showed that the thermistor has good quality because it has relatively large constant thermistor. Fe2TiO5 is one of semiconductors that used as basic material for main fabrication component of NTCs as temperature sensor. In this study, temperature measuring instrument using NTC Fe2TiO5 sensor based on microcontroller was made. The NTC is assembled in parallel with a fixed resistor and then assembled on ICLM741 and microcontroller ATMEGA 328. The magnitude of the resistor varies at 1 MOhm, 2 MOhm, and 3 MOhm with each resistor having a tolerance value of 1%. From these variations we get sensitivity value with the value of 0.0026 MOhm/ \(^{o}\)C, 0.0091 MOhm/ \(^{o}\)C, and 0.0155 MOhm/ \(^{o}\)C, respectively. As result, this temperature measuring instrument shows good sensitivity when assembled in parallel using 3 MOhm fixed resistor and capable of measuring the temperature in the range 26.3\(^{o}\)C until 134.5\(^{o}\)C.

Keywords: NTC Thermistor; Fe2TiO5; Temperature Sensor; Sensitivity; Temperature Range

Topic: Physics