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:
Mar. 06, 2012
Filed:
Nov. 12, 2008
Alexander Mednik, Campbell, CA (US);
Rohit Tirumala, Sunnyvale, CA (US);
Marc Tan, Sunnyvale, CA (US);
Alexander Mednik, Campbell, CA (US);
Rohit Tirumala, Sunnyvale, CA (US);
Marc Tan, Sunnyvale, CA (US);
Supertex, Inc., Sunnyvale, CA (US);
Abstract
A power supply circuit for powering a load at constant current has a rectifier stage for receiving an AC voltage input and for producing a first substantially DC voltage. A first capacitor is attached to the load. A charge-pump is attached to an output of the rectifier stage and to the load for providing power factor correction and for converting the first substantially DC voltage to a second substantially DC voltage at the first capacitor. The charge pump is prevented from conducting energy back into the output of the rectifier stage. The charge pump delivers energy to a charge pump output, the energy being delivered directly instead of being stored. A converter stage is attached to the load and the first capacitor. The converter stage is used for converting voltages at the first capacitor and the charge pump to an output DC current. The converter stage has a switch for periodically connecting a first series-coupled circuit of the charge pump to the output of the rectifier stage.