Class D audio amplifier
US7629842B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 2008 |
| Grant date | Dec 8, 2009 |
| Priority date | — |
| Expiry date | Apr 2, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/351
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A class D audio amplifier includes an error amplifier, a comparator, a bridge circuit, a feedback circuit and a silent start circuit. The error amplifier generates an error signal by amplifying a difference between a feedback signal and an audio input signal. The comparator generates a first pulse width modulation (PWM) signal by comparing a first triangular-wave signal and the error signal. The bridge circuit has switches alternately conducting a current flowing into and from a load. The feedback circuit generates the feedback signal indicating a condition of the load. The silent start circuit performs AND operation of the first PWM signal and a second PWM signal having a gradually increased duty ratio to generate a third PWM signal for control of the switches of the bridge circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.