Patent · US Expired

Capacitance measuring system

US4093915A · kind A · utility

30Cited by
8References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 29, 1977
Grant dateJun 6, 1978
Priority date
Expiry dateJun 29, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R27/2605
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A system for generating a signal linearly related to the capacitive reactance of a sensor capacitor. The system includes an oscillator for providing an oscillatory signal characterized by a peak-to-peak voltage proportional to an applied control signal, at least one capacitive network and associated peak detecting network, and a feedback network. The capacitive network includes a drive capacitor and a sensor capacitor connected in series between the oscillator and a reference potential, and the peak detector includes means to generate a peak signal representative of the peak-to-peak voltage at the junction between its associated coupling and sensor capacitor. The feedback network produces the control signal for the oscillator whereby the peak amplitude of the voltage across the drive capacitor is constant.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.