Type:
Journal
Description:
Sensing mechanisms of gas sensors depend on temperature, and this is in particular true for metal-oxide semiconductors where the peculiar role of temperature suggested the modulation of temperature as a viable method to tune selectivity and sensitivity. This principle was widely investigated in the past, and methods to design ad hoc temperature behaviors have been proposed. In this paper, instead of a priori temperature profiles, a self-adaptive temperature modulation is proposed. For the scope, a closed-loop circuit connecting the sensor resistance to the sensor heater is designed. In this condition changes in sensor resistance are reflected into changes of operating temperature. Herewith, the method is implemented with an oscillatory circuit, so with a steady resistance value the signal driving the temperature modulation converges to a periodic pattern of pulses that is specific for the sensor state. Since the …
Publisher:
Elsevier
Publication date:
3 Jan 2012
Biblio References:
Volume: 161 Issue: 1 Pages: 534-541
Origin:
Sensors and Actuators B: Chemical