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:
Jun. 01, 2010
Filed:
Nov. 29, 2005
Cho Sing Chan, Kowloon, HK;
Ronald J. Bezdon, Schaumburg, IL (US);
Cho Sing Chan, Kowloon, HK;
Ronald J. Bezdon, Schaumburg, IL (US);
Century Concept Ltd, Hong Kong, CN;
Abstract
A ballast circuit for controlling preheating, ignition or performing dimming of a gas discharge lamp such as a compact fluorescent lamp is disclosed. The ballast circuit has an inverter connected to a pair of input terminals for receiving a supply voltage, a base drive transformer connected to the switching transistor inverter to provide a drive signal, a resonant circuit connected to the switching transistor inverter, and a loading circuit connected to the base drive transformer. The base drive transformer includes a primary winding and a secondary winding set. The loading circuit is adapted for at least temporarily saturating the base drive transformer and thus effecting in the resonant circuit an oscillating frequency different from a natural resonant frequency of the resonant circuit.