A ballast control circuit for multiple lamps comprising a ballast control circuit for driving two series connected switches of a lamp ballast connected across a supply potential and having a switched node between the switches; the switched node adapted to be connected to an output circuit comprising a plurality of parallel connected lamps; the control circuit comprising an oscillator, the output circuit comprising the plurality of parallel connected lamps including inductive and capacitive components and having a resonance frequency that is dependent on the number of lamps in the output circuit; a lamp output voltage being developed across the output circuit; further comprising a feedback circuit for controlling the oscillator whereby the oscillator sweeps from a first frequency above resonance to a lower frequency closer to resonance such that the output voltage increases to a potential above a lamp ignition threshold, thereby igniting at least one lamp; the feedback circuit controlling the oscillator whereby the oscillator frequency reduces each time a lamp ignites, causing the output voltage across the output voltage circuit to increase above the threshold, thereby igniting another of the lamps.

 
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> Flat-type fluorescent lamp and liquid crystal display device having the same

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