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:
Dec. 21, 1999
Filed:
Aug. 29, 1997
Applicant:
Inventor:
Guichao Hua, Blacksburg, VA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02M / ;
U.S. Cl.
CPC ...
363 20 ; 363131 ;
Abstract
Improved AC/DC conversion in power supplies having an isolation transformer located between rectified-AC input and DC output leads. The transformer is given a primary winding having one or more taps, and a positive input lead is connected thereto by a corresponding number of intermediate leads, each containing selected components. The improvement not only enables power factor correction (PFC) but also desired adjustment of or control over other operational variables, such as bulk capacitor voltage stress, output regulation, and overall efficiency, often at a reduction in circuit complexity and cost.