High efficiency driver for miniature loudspeakers
US7336794B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 2002 |
| Grant date | Feb 26, 2008 |
| Priority date | — |
| Expiry date | Dec 9, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R25/505
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a first aspect the present invention provides a compact high efficiency driver suitable for driving a loudspeaker, such as a miniature loudspeaker for mobile phones or hearing aids. The driver comprising an interface for receiving an input signal, a three-level modulator, and a three-level H-bridge. The interface may be adapted to receive a digital input signal. In a preferred embodiment of the driver the H-bridge is controlled by a correction circuit which is operated by a Return-To-Zero scheme. In a further preferred embodiment the driver comprises a supply voltage step-up circuit for increasing a voltage supplied to the H-bridge. In a second aspect the present invention provides a miniature loudspeaker assembly having a built-in driver. In a third aspect the present invention provides a mobile device with a built-in miniature loudspeaker assembly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.