Patent · US Expired

Multistep flash analog to digital converter with voltage estimator

US4918449A · kind A · utility

9Cited by
14References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 13, 1989
Grant dateApr 17, 1990
Priority date
Expiry dateFeb 13, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M1/365
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A novel multistep flash analog to digital converter is taught, including a voltage estimator which quickly provides a rough estimate of the analog input signal. This rough estimate is used to select appropriate reference voltage tap points for use in the first flash conversion. This first flash conversion, together with the voltage estimate, provides the most significant bits of the digital output word. A digital to analog converter is used to provide a residual voltage which is then converted by a second operation of the flash converter, thereby providing the least significant bits of the digital output word. In one embodiment, the voltage estimate is performed at the same time that the analog input signal is sampled by the flash converter in preparation for the first flash conversion. Therefore, speed of operation is not degraded by the addition of the voltage estimator.

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