Arduino-Based Shield for Resistive Gas Sensor Array Characterization Under UV Light Exposure

In this paper, the development and validation of a shield prototype for resistive sensor array characterization with Arduino UNO, a platform based on ATmega328 microcontroller provided by ATMEL, is reported. The resistance variation of the sensor can be e

  • PDF / 269,781 Bytes
  • 5 Pages / 439.37 x 666.14 pts Page_size
  • 65 Downloads / 253 Views

DOWNLOAD

REPORT


1

Introduction

The development of nanostructured sensing material and its integration in microelectronics devices are the key for the actual increasing of sensors market. Nanostructured sensing material optimization can be considered as the turning point for the development of devices able to achieve the right balance between low power consumption requirements and sensing performance. The low power consumption requirements can be fulfilled by developing sensing materials able to operate itself at conditions close to room temperature or by UV “activation.” As an example of this concept, mesoporous In2O3-based material can be irradiated with UV light to enhance the sensing properties to decrease the operating temperature value [1]. Therefore, new applications and services are arising, supported by the improvement of new portable and low-cost sensing systems. In such task, here is reported the development of a characterization system for metal oxide (MOX)-based gas sensors with Arduino UNO platform. The developed shield is able to measure the response of up to six sensors under UV radiation by means of LED devices. In the shield

D. Aloisio (*) • N. Donato • G. Neri Department of Electronic Engineering, Chemistry and Industrial Engineering, University of Messina, Contrada di Dio, Messina 98166, Italy e-mail: [email protected] M. Latino Consiglio Nazionale Delle Ricerche, Istituto per la Microelettronica e Microsistemi, Zona Industriale VIII Strada 5, Catania 95121, Italy T. Wagner • M. Tiemann Naturwissenschaftliche Fakultät, Department Chemie, Universität Paderborn, Warburger Straße 100, Paderborn 33098, Germany P.P. Capra Istituto Nazionale di Ricerca Metrologica, Torino 10135, Italy 411 C. Di Natale et al. (eds.), Sensors and Microsystems: Proceedings of the 17th National Conference, Brescia, Italy, 5-7 February 2013, Lecture Notes in Electrical Engineering 268, DOI 10.1007/978-3-319-00684-0_79, © Springer International Publishing Switzerland 2014

412

D. Aloisio et al.

takes place the board with six inverter-based oscillators where the RC tank of every circuit is composed of the resistance of the sensor (R) and an external capacitance (C). By properly choosing the capacitance value and by measuring the period (frequency) of the oscillator, the resistance response of each sensor can be evaluated.

2

Experiments

The mesoporous sensing material development and characterization were reported in previous papers [1, 2]. Here are reported the experimental activities regarding the board for hardware interfacing. A good alternative to realize real-time resistance measurements is to use an oscillator system whose frequency is resistance value dependent [3]. This approach avoids the use of A/D converters and simplifies the interfacing circuit of the sensor. The measurement system core is based on an oscillator circuit in which frequency depends on the resistor value present in the RC tank of the resonant ring. It is based on two inverter gates and a Schmidt trigger, essential for a proper RC charge and discharge, all