The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 17, 1994
Filed:
Aug. 31, 1992
Ralph M Francis, Jr, Racine, WI (US);
Michael Garjian, Stoughton, MA (US);
Other;
Abstract
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.