Digital differential capacitive angle transducer

A high accuracy, easy to fabricate, capacitive angle transducer that provides a digital output linearly proportional to the angle being sensed in he range 0° to 360° is presented. The variations in the sensor capacitances are converted to digital employing dual slope digital conversion principle. High accuracy is easily obtained since the output is dependent only on a dc reference voltage and a high frequency clock. The signal conditioning circuitry is configured such that the effect due to stray capacitances on the output is completely eliminated. A prototype developed and tested validates the practicality of the proposed method. ©2007 IEEE.