Appllication of switched-capacitor self-oscillating circuits to the conversion of RLC parameters into a frequency or digital signal

Abstract In this paper, the applicability of CMOS switched-capacitor (SC) techniques to the design of converters with digital, frequency or duty-cycle output is investigated and discussed. New SC converters which enable resistances Rx, inductances Lx, capacitances Cx and time constants RxCx or Lx/Rx to be converted into a frequency (or period) are proposed and tested. The output frequency of the converters can be used directly as an input signal for mini/microcomputer- or microprocessor-based systems.

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