Circuits and methods for reducing pop noise in class D amplifiers
US8265303B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 2009 |
| Grant date | Sep 11, 2012 |
| Priority date | — |
| Expiry date | Mar 25, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F3/217
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In one embodiment the present invention includes a method for starting up a class D amplifier. The method comprises increasing, gating, and driving. The increasing includes increasing a duty cycle of a pulse train from a first duty cycle to a second duty cycle. The gating includes gating a signal based on the increasing of the duty cycle. The gating results in a gated signal. The driving includes driving an output signal from the gated signal to charge an output capacitor. The output capacitor is coupled to a speaker. The increasing of the duty cycle contributes to the charging of the output capacitor such that switching sounds detectable by the human ear are reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.