Patent · US Expired

Two-step parallel analog to digital converter

US4875048A · kind A · utility

108Cited by
6References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 29, 1988
Grant dateOct 17, 1989
Priority date
Expiry dateAug 29, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M1/361
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

In a two-step parallel analog to digital converter of the type in which a first flash-type A/D converter determines the upper significant bits of a digital signal output having a desired number of bits and after a quantizing error of the first flash-type A/D converter has been determined from the difference between a value obtained by reconverting the upper significant bits to an analog value and the input analog value a second flash-type A/D converter subjects the quantizing error to A/D conversion to determine a digital output of the remaining lower significant bits, a gain correcting circuit is additionally provided to automatically establish a gain of a D/A converter for reconverting the upper significant bits to an analog value on the basis of a reference voltage applied to the first flash-type A/D converter. Moreover, a reference voltage generating circuit is additionally provided to establish upper and lower reference voltages of a second flash-type A/D converter for determining lower significant bits on the basis of the step voltage of the DAC output.

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