Patent · US Expired

Multi-level Class-D amplifier by means of 2 physical layers

US6842070B2 · kind B2 · utility

69Cited by
10References
42Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 30, 2003
Grant dateJan 11, 2005
Priority date
Expiry dateJul 25, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F2200/331
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

Introduce a pulse length control mechanism to generate virtual multi-level output pulses for a Class-D Amplifier, which has only 2 physical output levels. Typically a Sigma-Delta-Modulator converts the input signal into high frequency low bit rate. The disclosed invention adds functions to transform the SDM signal into pulses with equivalent multi-level time-voltage areas and adds a pulse-length-control mechanism to produce various output pulse patterns, where the summations of the positive and negative pulses, within one sampling period, result in time-voltage area values, corresponding to 3 or more digital levels. Thus the invention produces higher signal quality at lower sampling rates.

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