Patent · US Expired

Impedance/admittance measuring circuit

US4283675A · kind A · utility

9Cited by
3References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 12, 1979
Grant dateAug 11, 1981
Priority date
Expiry dateMar 12, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R27/02
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An impedance/admittance measuring circuit generates an output signal which is representative of the real or imaginary part of the impedance or admittance of a connected load. An excitation signal comprising a square wave having a fixed magnitude is generated and applied to a load. The response signal resulting from the excitation signal is filtered by a two pole bandpass filter (106). The filter output signal is used to control the excitation signal generator (101, 102) such that an oscillatory feedback loop is formed. By controlling the load connection and the phase relations between the excitation signal and the filter output signal, the magnitude of the output signal is representative of the real or imaginary part of the impedance or admittance of the connected load (103).

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