AC-DC single-inductor multiple-output LED drivers
US10212770B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 2015 |
| Grant date | Feb 19, 2019 |
| Priority date | — |
| Expiry date | Apr 23, 2035 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A single-stage AC-DC single-inductor multiple-output (SIMO) LED driver uses a single inductor (L) to drive multiple independent LED strings (341-34n) with Power Factor Correction (PFC). The driver uses a diode bridge (20) to achieve initial AC to DC conversion. The output of the bridge (20) is provided to a buck converter whose output is shared with multiple LED strings by a time division multiplex circuit. Feedback is used to separately control the current supplied to each LED string by using a separate reference for each string and controlling the width of the current pulse provided to a string. Current balancing in every LED string can be achieved with the same voltage reference without the need for additional circuitry.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.