Zero-crossing detection circuit
US9444321B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 23, 2015 |
| Grant date | Sep 13, 2016 |
| Priority date | — |
| Expiry date | Jan 23, 2035 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B70/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In one embodiment, a zero-crossing detection circuit can include: (i) a first detection circuit configured to detect a current through a main transistor of a main circuit of a switching power supply, and to generate a voltage sense signal that represents the current through the main transistor; (ii) a second detection circuit configured to detect if quasi-resonance occurs in the main circuit, the second detection circuit being configured to generate at least one pulse signal when the quasi-resonance is detected; and (iii) a control circuit configured to receive the at least one pulse signal and the voltage sense signal, to turn the main transistor off when the current through the main transistor reaches a predetermined value, and to turn the main transistor on when the at least one pulse signal is active.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.