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:
Sep. 18, 1990
Filed:
Sep. 19, 1989
Charles B Mattas, Glenview, IL (US);
Egbert Van Zanten, Eindhoven, NL;
Stefan P Szuba, Parkridge, IL (US);
North America Philips Corporation, New York, NY (US);
Abstract
Apparatus for starting and operating a high pressure discharge lamp includes a pair of input terms for connection to a high frequency inverter. A step-up transformer couples the input terminals to a pair of output terminals for connection of the discharge lamp. A switching arrangement including a voltage-multiplier circuit, is coupled to the primary winding of the transformer and includes a first branch comprising a first capacitor and a diode and a second branch comprising a diode. Between the first capacitor and the diode of the first branch is connected a third branch comprising a semiconductor switch such as a SIDAC. The first branch is connected through the transformer coil to a first supply source connection point. The second branch is connected to a tap point of the coil. The first and the second branch are connected via a common impedance including second capacitor and an inductor to a second supply source connection point. The third branch is connected directly to both the coil and the diode of the second branch. The SIDAC periodically switches over from a cut-off state to a conductive state in response to a voltage developed across one or more capacitors of the voltage-mulitplier circuit thereby to rapidly discharge the capacitor voltage across the winding of the step-up transformer. A high voltage ingnition pulse is generated in the secondary of the step-up transformer and is applied to the output terminals to ignite a connected discharge lamp.