Control circuit and method for driving a gas discharge lamp
US7663324B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 23, 2006 |
| Grant date | Feb 16, 2010 |
| Priority date | — |
| Expiry date | Apr 24, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/2821
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control circuit (1) for driving a gas discharge lamp, in particular a fluorescent lamp (FL), having a controllable converter (2) for converting a DC voltage to an AC voltage and having two feed lines (3, 4), which are connected on the AC-voltage side to the converter (2), and between which the gas discharge lamp can be connected, an inductor (L1), a first capacitance (C1) and a first controllable switching element (T1) being connected in series in the feed lines (3, 4). The feed lines (3, 4) are connected to one another via a second switching element (T2). A control unit (ST2) controls the switching elements (T1, T2, T3) in synchronism with the AC voltage of the converter (2) and is designed such that the second switching element (T2) is opened after a closed phase for the purpose of starting the gas discharge lamp at such a point in time that the AC voltage at the inductor (L1), which is set in the resonant circuit including the inductor (L1) and the parasitic capacitance (C4) of the second switching element (T2), and the AC voltage of the converter (2), approximately in-phase in terms of their extrema, are added to give a starting voltage. Furthermore, provided is a correspondi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.