Switching amplifier with enhanced supply rejection and related method
US8237496B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 2010 |
| Grant date | Aug 7, 2012 |
| Priority date | — |
| Expiry date | Aug 19, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F3/217
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Disclosed is a switching amplifier having an enhanced supply rejection. The switching amplifier comprises a digital modulator that provides a modulated signal. The switching amplifier further comprises a closed-loop analog driver that is coupled to the digital modulator. As disclosed, the closed-loop analog driver is configured to re-modulate a modulation signal that corresponds to the modulated signal. An output stage of the switching amplifier is driven by the re-modulated signal, thereby providing enhanced supply rejection. In one embodiment, the modulated signal is produced by a digital pulse-width modulator (PWM) circuit of a Class-D amplifier, and has a pulse rate substantially less than a clock rate of the digital PWM circuit. In one embodiment, the switching amplifier is implemented as an audio amplifier in a mobile communication device such as a cellular telephone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.