Two-stage LED driver with selectable dual output current
US9301350B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 1, 2013 |
| Grant date | Mar 29, 2016 |
| Priority date | — |
| Expiry date | Oct 1, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/38
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A two-stage LED driver for providing a substantially constant output current to an LED load, and related methods and systems. The first stage of the LED driver includes a conventional power factor correction (PFC) circuit that outputs a direct current (DC) voltage and a DC current. The second stage of the LED driver includes a low voltage flyback circuit that receives the DC voltage and the DC current. The low voltage flyback circuit includes a flyback transformer and a switch circuit that selectably toggles the substantially constant output current provided by the low voltage flyback circuit to the LED load between a first and a second, preset constant current. The secondary windings of the flyback transformer are split into two sections, and the switch circuit toggles the two sections of the secondary windings between a series and a parallel configuration to provide the first and second, preset constant currents.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.