Electrical equivalent models of semiconductor gas sensors using PSpice

In this paper we present a new PSpice behavioural model of metal oxide resistive gas sensors. The sensor model, which is based on previously developed theoretical and experimental analyses, depicts the static and dynamic responses of the sensors to multicomponent gas mixtures. The dynamic response is obtained either when the gas concentration or the operating temperature of the sensor are modulated. The model developed is in good agreement with experimental data. PSpice also gets equivalent results up to 10 times faster (on the same PC platform) than when the diffusion-reaction equations that model the response of sensors are solved numerically.