| 摘要 |
The invention relates to a ballast circuit for running multiple fluorescent lamps of at least two fluorescent lamps, the multiple fluorescent lamps are connected in series and divided into groups of every two lamps, comprising: LC resonance circuits for igniting respective groups of the two fluorescent lamps, a DC block capacitor for conducting the electric current from the resonance capacitor to ground, wherein the ballast circuit further comprising sequence start capacitors (C3, C4) that are connected through the filaments between both LC resonance circuits when there are two fluorescent lamps, or connected from each LC resonance circuit to the connection point of the other group of lamps when there are more than two fluorescent lamps, for limiting the electric voltage generated on the respective resonance capacitor when one of the lamps is broken in a corresponding group of fluorescent lamps. |
