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. 26, 1998
Filed:
Nov. 30, 1995
Sameer Sodhi, Palatine, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
An electronic power supply circuit (12) having a rectifier circuit (18) adapted to receive a source of alternating current (10), a power factor correction driven boost converter (20), and a bulk capacitance (22). The boost converter (20) includes a boost transformer (24) having a primary winding (32) and a secondary winding (34), a boost switch (26), a boost diode (28), a zener diode (46), and a power factor correction control circuit (30) having a zero current detect input (58). The presence of the zener diode (46) effectively adds a fixed offset to the voltage provided to the zero current detect input (58), thereby allowing the boost converter (20) to operate under high input line voltage conditions. The zener diode (46) may be oriented in various ways, and may be incorporated into an integrated circuit containing other elements of the power factor correction control circuit (30). One particular embodiment of the power supply circuit (12) is for use in an electronic ballast (70) for fluorescent lamps.