| 摘要 |
A solid-state ballast for discharge lamps includes circuitry for limiting the maximum output voltage produced when a lamp is first being ignited or is removed. The ballast includes a signal controlled oscillator that provides the operating signal for a resonantly driven lamp load. The voltage across the load is sensed and a signal representing this voltage is fed back to a circuit when controlling the oscillator so as to limit the maximum load voltage during initial start-up and when a lamp is removed. In accordance with a second embodiment, the voltage is cycled between a low level and a level high enough to ignite the lamp, so long as the lamp is not ignited.
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