Flexible high-accuracy wide-range gas sensor interface for portable environmental nosing purpose

In this paper, we present a flexible high-precision wide-range front-end for resistive sensors. The output of a programmable continuous-time transresistance stage is processed by a differential switched-capacitor incremental A/D converter. A digital signal processor reconfigures the interface leading to a resolution of 0.1% over a range of 5 decades, as required by pattern recognition algorithms for sensors arrays in environmental nosing applications. Particular care has been taken in reducing the power consumption.