Dimming circuit, control circuit and dimming method
US9999106B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 26, 2017 |
| Grant date | Jun 12, 2018 |
| Priority date | — |
| Expiry date | Jan 26, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/375
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A dimming circuit for adjusting the brightness of an LED load, can include: a primary controlled flyback converter having a primary-side circuit, a first secondary-side circuit, and a second secondary-side circuit; a DC-DC converter coupled in a cascade arrangement with the second secondary-side circuit, where an output node of the DC-DC converter is coupled in series to an output node of the first secondary-side circuit; a control circuit configured to control, according to a dimming signal that represents an expected output current of the dimming circuit, a power switch of the primary controlled flyback converter to adjust output voltages of the first and second secondary-side circuits, to adjust a power that is provided to the LED load; and the control circuit being configured to control a power switch of the DC-DC converter according to the dimming signal, such that the DC-DC converter operates within a predetermined state range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.