Patent · US Expired

Power supply rejection for pulse width modulated amplifiers and automatic gain control

US7135922B2 · kind B2 · utility

7Cited by
1References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 7, 2005
Grant dateNov 14, 2006
Priority date
Expiry dateJan 7, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F2200/78
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A circuit according to the present invention improves the power supply rejection ratio for a pulse width modulated digital amplifier and can be used as a compressor and/or limiter. The circuit preferably operates by using voltage level translation to vary the amplitude of a triangle wave in response to changes in power supply voltage prior to input of the wave into a comparator of the PWM device. Because the circuit operates to improve power supply rejection, little or no distortion is introduced into the signal when used as a compressor and/or limiter. Additionally, the circuit is optionally implemented in a Class D amplifier, and provides a lower cost of implementation than conventional designs in such implementations.

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