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. 29, 1990
Filed:
Apr. 07, 1989
William F Slack, Lake Hiawatha, NJ (US);
James C Wadlington, Mendham, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
An arrangement for improving the power factor at the input of an off-line switching type power supply is operative to extend the duration of the pulse current conducted by the diode rectifiers. A parallel LC ringing circuit is introduced between the AC line and the rectifier of the switching type power supply to enhance the voltage enabling conduction of the rectifying diodes and hence initiate current flow through the rectifying diodes earlier in each half cycle. This extends the conduction interval of the rectifying diodes significantly and enhances the power factor at the input to the switching type power supply.