Patent · US Expired

Digital-to-analog conversion circuit

US5019819A · kind A · utility

6Cited by
4References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 26, 1990
Grant dateMay 28, 1991
Priority date
Expiry dateApr 26, 2010

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M3/502
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A digital-to-analog conversion circuit capable of preventing a noise produced in a digital system from mixing in an analog output has an input circuit receiving a pulse-code modulated digital signal, a conversion circuit such as a noise shaping circuit for converting the pulse-code modulated digital signal to a pulse wave signal containing analog amplitude information in a time axis direction, a buffer circuit including an electrically insulated coupling circuit such as an optical coupling circuit for transmitting output of the conversion circuit, and an analog output circuit including an analog low-pass filter for delivering out output of the buffer circuit therethrough. A noise generated in a digital system is intercepted by the buffer circuit and is not transmitted further so that mixing of the noise in the analog output circuit is prevented.

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