Title :
Switched Capacitor Signal Conditioning for Differential Capacitive Sensors
Author :
George, Boby ; Kumar, V. Jagadeesh
Author_Institution :
Dept. of Electr. Eng., Indian Inst. of Technol. Madras, Chennai
fDate :
6/1/2007 12:00:00 AM
Abstract :
A novel switched capacitor signal-conditioning circuit for differential capacitive sensors is proposed. The main advantage of the proffered method lies in the fact that it accepts sensors possessing either linear or inverse characteristics and provides a linear output. Moreover, the output is dependent only on a pair of dc reference voltages and the transformation constant of the sensor. Hence, increased linearity and accuracy is easily achieved by employing precision dc reference voltages. Results from the tests on a prototype elucidate the practicality of the proposed method
Keywords :
capacitive sensors; signal processing equipment; dc reference voltages; differential capacitive sensors; sensor transformation constant; signal conditioning circuits; switched capacitor circuits; Capacitance; Capacitive sensors; Equivalent circuits; Force measurement; Linearity; Sensor phenomena and characterization; Switched capacitor circuits; Switching circuits; Transducers; Voltage; Capacitive sensors; differential capacitive sensor; ratio-metric measurement principle; signal conditioning; switched capacitor circuits;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
DOI :
10.1109/TIM.2007.894802