A Resistance Deviation-To-Time Interval Converter Based On Dual-Slope Integration

A resistance deviation-to-time interval converter based on dual-slope integration using second generation current conveyors (CCIIs) is designed for connecting resistive bridge sensors with a digital system. It consists of a differential integrator using CCIIs, a voltage comparator, and a digital control logic for controlling four analog switches. Experimental results exhibit that a conversion sensitivity amounts to 15.56 ㎲/Ω over the resistance deviation range of 0-200 Ω and its linearity error is less than ±0.02%. Its temperature stability is less than 220 ppm/℃ in the temperature range of -25-85℃. Power dissipation of the converter is 60.2 mW.