Patent · US Expired

Circuit and method for pulse width modulation

US7391280B2 · kind B2 · utility

27Cited by
3References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 10, 2004
Grant dateJun 24, 2008
Priority date
Expiry dateMar 25, 2026

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K7/08
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A circuit and a method for performing pulse width modulation are provided. A pulse density modulator (PDM) is applied to receive the least N bits of the input data and to generate a pulse density modulation signal. The number of pulse of the pulse density modulation signal in 2^N frames correspond to a value of the least N bits of the input data. An adder is applied to generate a PWM data by adding a value of the most M bits of the input data to a value of the pulse density modulation signal generated by the PDM. A pulse width modulator is applied to generate a PWM signal dithering in 2^N frames according to the PWM data generated by the adder, so as to improve the audio quality of pulse width modulation and the Electro-Magnetic Interference (EMI) phenomenon.

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