Title :
A switched-capacitor interface for differential capacitance transducers
Author :
Watanabe, Kenzo ; Ogawa, Satomi ; Oisugi, Yutaka ; Kondo, Kazuyuki
Author_Institution :
Res. Inst. of Electron., Shizuoka Univ., Hamamatsu, Japan
Abstract :
For high-accuracy signal processing of differential capacitance transducers, an interface circuitry based on a switched-capacitor sample/hold circuit is developed. Driven by nonoverlapping two-phase clocks, the interface produces the output voltage which is proportional to the ratio of difference-to-sum of two capacitors of a differential transducer. SPICE simulations show that 0.1% resolution is easily achievable with the simple configuration. Experimental results are given to confirm the simulation
Keywords :
CMOS analogue integrated circuits; SPICE; capacitive sensors; equivalent circuits; microsensors; operational amplifiers; sample and hold circuits; signal processing equipment; switched capacitor networks; CMOS interface; SC interface circuitry; SC sample/hold circuit; SPICE simulation; differential capacitance transducers; equivalent circuit; high-accuracy signal processing; ideal op amp; micromachined transducers; nonoverlapping two-phase clocks; ratiometric operation; Capacitance; Capacitors; Circuit simulation; Clocks; SPICE; Signal processing; Signal resolution; Switching circuits; Transducers; Voltage;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 1999. IMTC/99. Proceedings of the 16th IEEE
Conference_Location :
Venice
Print_ISBN :
0-7803-5276-9
DOI :
10.1109/IMTC.1999.776768
