Switching power supply control circuit with bottom point detection
US11005373B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 30, 2018 |
| Grant date | May 11, 2021 |
| Priority date | — |
| Expiry date | Oct 30, 2038 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B70/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A switching power supply apparatus includes a switching device and a switching power supply control circuit for converting an AC source voltage to a DC voltage. A comparison circuit in the switching power supply control circuit produces an H-level output signal when its non-inverted input voltage exceeds a voltage value during each off-state period of the switching device. A delay circuit outputs a pulse signal after a predetermined delay time from detecting the H-level signal. This pulse signal indicates detection of a bottom point of drain voltage of the switching device. Since the output of the delay circuit is directly connected to the set input terminal S of a flip-flop, the switching device is surely turned on, without bottom skip, upon detection of the bottom point of its drain voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.