A bridge circuit for temperature drift cancellation

A bridge circuit is developed for cancelling temperature drifts of resistive sensors. It consists basically of two half bridges with a common reference arm, each one followed by a differential amplifier. The gains of the amplifiers are adjusted such that the half-bridge output voltages due to temperature variation of sensors cancel each other. This scheme allows a compensation for a large mismatch in the temperature sensitivity of sensors without degrading their inherent sensitivities. Experimental results are presented to demonstrate the validity of this concept