Patent · US Expired

Autocalibrated multistage A/D converter

US4908621A · kind A · utility

43Cited by
9References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 6, 1988
Grant dateMar 13, 1990
Priority date
Expiry dateJul 6, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M1/167
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An autocalibrated multistage analog to digital converter precisely maintains appropriate error correction levels for each stage during operation of the converter to minimize quantization errors. An error signal is derived from the digital output of the converter based upon the slope of the input analog signal, determined either explicitly via hardware or implicitly via software, and an overflow/underflow condition. The error signal is fed back to a calibration control circuit to generate individual error correction levels for various variable correction devices within the analog to digital converter, such as a variable analog delay device. The variations from nominal established at calibration that are due to age, temperature or other environmental factors generate the error signal that varies from a nominal value and is fed back to alter the various error correction levels to minimize the error variation.

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