Patent · US Expired

Oversampled A/D converter using filtered, cascaded noise shaping modulators

US4862169A · kind A · utility

31Cited by
4References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 25, 1988
Grant dateAug 29, 1989
Priority date
Expiry dateMar 25, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M3/418
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An oversampling A/D converter for high resolution data conversion is provided. An analog input signal is quantized into a digital equivalent value with a finite quantization error associated therewith in a first circuit portion. An analog low pass filter is inserted between the first circuit portion and a second circuit portion similar in function and circuitry to the first circuit portion. The second circuit portion functions to remove the error of the first circuit portion from an output signal by providing a signal component, which when added with the output of the first circuit portion cancels the error of the first circuit portion. The low pass filter provides attenuation of quantization error provided by the second circuit portion which results in an output signal with a significantly attenuated error.

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