Common-mode leakage error calibration for current sensing in a class-D stage using a pilot tone
US11290070B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 7, 2020 |
| Grant date | Mar 29, 2022 |
| Priority date | — |
| Expiry date | Oct 5, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/481
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A system may include a Class-D stage comprising a first high-side switch coupled between a supply voltage and a first output terminal of the Class-D stage, a second high-side switch coupled between the supply voltage and a second output terminal of the Class-D stage, a first low-side switch coupled between a ground voltage and the first output terminal, and a second low-side switch coupled between the ground voltage and the second output terminal. The system may also include current sensing circuitry comprising a sense resistor, such that an output current through a load coupled between the first output terminal and the second output terminal causes a first sense voltage proportional to the output current across the sense resistor. The system may additionally include a modulator for generating a differential pulse-width modulation driving signal to the first high-side switch, the second high-side switch, the first low-side switch, and the second low-side switch and pilot tone injection circuitry configured to inject a periodic pilot tone into the differential pulse-width modulation driving signal at a pilot tone frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.