High bandwidth circuits for the measurement of small resistance changes

In this paper we present current-mode circuits for measuring small resistance changes such as in RTDs and strain gages. These circuits make use of current conveyors to achieve wider bandwidth in contrast to the conventional circuits which rely on opamps. Furthermore, it uses single calibrating resistor which can take care of many non-ideal effects on the part current conveyor and that due to tolerances of resistors and power supplies. Also, multiple sensors can be used in these circuits without having need of any additional circuit elements. Simulations performed using SPICE of the proposed circuits confirms the idea presented in this work.