摘要 |
An excitation circuit for a gas discharge lamp. The excitation circuit includes a rectifier for converting conventional line A.C. to D.C. The primary winding of a step up transformer and a switching element of an inverter circuit are connected in series across the output of the rectifier. The switching element is switched at a desired frequency, generating an A.C. signal across the primary winding of the transformer. The inverter circuit further includes a capacitor connected in parallel with the primary winding to provide a pseudo-resonant mode of operation in the primary winding when the switching element is off. Switching of the switching element is controlled by control circuitry, which responds to the voltage level at the interconnection of the primary winding and switching element for adjusting the relative on and off time of the switching element, controlling total current through the primary winding.
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