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. 04, 2010
Filed:
Nov. 17, 2005
Nigel Ashley Preston, Peterborough, CA;
Jamie A. Macdonald, Belleville, CA;
Nigel Ashley Preston, Peterborough, CA;
Jamie A. MacDonald, Belleville, CA;
Magna International Inc, Concord, Ontario, CA;
Abstract
A novel and advantageous power supply is disclosed for lighting systems employing semiconductor light sources where the semiconductor light sources are connected in series. The power supply includes a constant current source to supply current to the semiconductor light sources and a bypass switch is provided around each semiconductor light source, or each sub-string of series connected semiconductor light sources. By opening or closing respective bypass switches, individual semiconductor light sources or sub-strings of semiconductor light sources can be illuminated or extinguished as desired. If the bypass switches are electrically controllable, such as semiconductor switches or relays, failures of one or more semiconductor light sources can be determined by the power supply and failed light sources can be bypassed and/or redundant semiconductor elements illuminated to replace failed light sources. Further, if the bypass switches are semiconductor switches, the power supply can employ pulse width modulation techniques to dim one or more semiconductor light sources as desired.