A SWITCHED-CAPACITOR INTERFACE FOR CAPACITIVE SENSORS BASED ON RELAXATION-OSCILLATORS

被引:15
作者
CICHOCKI, A [1 ]
UNBEHAUEN, R [1 ]
机构
[1] UNIV ERLANGEN NURNBERG,W-8520 ERLANGEN,GERMANY
关键词
D O I
10.1109/19.58630
中图分类号
TM [电工技术]; TN [电子技术、通信技术];
学科分类号
0808 ; 0809 ;
摘要
A new switched-capacitor (SC) interface for capacitive sensors has been proposed based on a modified Martin’s relaxation oscillator. The output signal is the duty cycle of a pulsewidth modulated square-wave voltage or a binary-coded digital signal which is directly related to the capacitance ratio of an unknown capacitance Cx and a reference capitance Cr. The circuit can be implemented in a monolithic IC form using presently available CMOS technology. It requires a relative small device count integrable onto a small chip area and it is suited particularly for the on-chip interface circuitry for microprocessors. © 1990 IEEE
引用
收藏
页码:797 / 799
页数:3
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