Electronic interface for the accurate read-out of resistive sensors in low voltage-low power integrated systems

The accuracy of integrated sensors is often limited by errors of the electronic interface; this is the case in most low voltage-low power integrated sensor systems. In this paper we describe the dynamic op amp matching (DOAM) technique; the circuits using the dynamic op amp matching (DOAMCs) are a new type of circuits using dynamic element matching (DEMCs). In comparison with traditional DEMCs and with chopper circuits, DOAMCs may achieve a gain enhancement, while, in comparison with gain enhanced autozero circuits, they offer better noise performance. For these reasons DOAMCs are an attractive strategy for the implementation of accurate electronic interfaces in low voltage-low power integrated sensors; as a design example we present a DOAMC suitable for the read-out of resistive sensors. (C) 2004 Elsevier B.V. All rights reserved.