Power supply compensation for noise shaped, digital amplifiers
US6344811B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 16, 2000 |
| Grant date | Feb 5, 2002 |
| Priority date | — |
| Expiry date | Mar 16, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M3/506
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The digital amplifier of the present invention comprises a delta sigma noise shaper feeding a pulse wave modulator (PWM) which drives a load such as a speaker. The amplifier includes circuitry to measure the voltage coming out of the power supply in the circuit, and using this measurement as a control signal to modify the feedback path and direct path of the noise shaper, in order to correct the pulse width output to compensate for the varying power supply voltages. The amplifier may also include circuitry to correct for the nonlinear effects of pulse wave modulation, by correcting the feedback applied to one stage of the noise shaper such that it is nontrivially different from the feedback applied to another stage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.