Power supply for a gaseous discharge device

摘要

A transformer has a primary winding connected in series with a direct current source, a solid state switch and a current sensing resistor. A reactive element is coupled to the primary winding to form a resonant circuit. A high voltage for exciting a gaseous discharge device is produced across a first secondary winding of the transformer. A second resistor couples a terminal of the direct current source to one plate of a storage capacitor that has another plate connected to a second terminal of the direct current source. The one plate of the storage capacitor also is connected to a second secondary winding of the transformer. The control circuitry for the power supply is biased by voltage stored across the capacitor. A circuit branch applies a bias potential to a control electrode of the solid state switch to render the switch conductive, and has a delay element which prevents the solid state switch from becoming conductive until a sufficient voltage level exists across the storage capacitor to bias the control circuitry into operation. A switch circuit a turns off the solid state switch either when the voltage across the first resistor exceeds a given level or when the voltage across the second secondary winding exceeds a predefined magnitude.