Patent · US Expired

Multibit delta-sigma modulator with variable-level quantizer

US6940437B2 · kind B2 · utility

5Cited by
2References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 2003
Grant dateSep 6, 2005
Priority date
Expiry dateFeb 5, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M7/3037
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A method of operating a delta-sigma modulator by providing a variable-level quantizer, which selectively enables an additional quantizer level(s) during a ramp up sequence of the modulator. The additional quantizer level(s) is/are disabled during normal operation. The quantizer truncates a summer output and selectively enables the additional quantizer levels by clipping the truncated sum within a first range of quantizer levels during the ramp up sequence and within a second range of quantizer levels during normal operation in which there are more quantizer levels in the first range than in the second range. The quantizer preferably enables at least two additional quantizer levels at a low end of the quantizer range. For example, the range of quantizer levels for normal operation of the modulator can be from −6 to +6, while the range of quantizer levels for ramp up operation of the modulator can be from −8 to +7.

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