Patent ID: 7456583
Filing Date: 2008-11-25
Classification: H05B

Abstract:
1. A circuit for igniting and operating a gas discharge lamp, the circuit comprising: an inverter comprising a plurality of power switches set to operate at a first switching frequency during a lamp ignition mode to supply a variable voltage output signal; and a resonant circuit connected to receive the variable voltage output signal from the inverter, wherein said resonant circuit comprises a first circuit stage and a second circuit stage, and further wherein the second circuit stage includes a resonant tank circuit configured to generate a resonant output voltage when the switching frequency of the inverter matches a resonant frequency of the resonant circuit, and wherein the first circuit stage comprises at least one current-suppressing element for reducing a fluxing effect of a resonant current that flows in the resonant circuit on a switching current that flows in the inverter, said flux-reducing effect occurring when the switching frequency of the inverter matches the resonant frequency of the resonant circuit, wherein the resonant current essentially flows just through the second circuit stage.