Patent · US Expired

Charge balanced feedback transmitter

US4878012A · kind A · utility

55Cited by
5References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 10, 1988
Grant dateOct 31, 1989
Priority date
Expiry dateJun 10, 2008

Classification

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

Abstract

A charge balanced feedback type transmitter generates charge packets representative of a sensed parameter. Improved performance is achieved by the additiion of resistance connected between a charge packet generating reactance and an integrator to reduce the effects of noise caused by switching transients and by ground noise which is coupled to the charge packet generating circuitry by stray capacitance. The charge packets are integrated by the integrater, and the integrator output is supplied from a selective basis to the input of a comparator. The output of the comparator is used to control the application of charge packets to the integrator to achieve charge balance. The input of the comparator is selectively connected to the output of the integrator, to a first supply voltage, or to a second supply voltage to ensure a stable output of the comparator at a critical time when charge is being supplied to the integrator.

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