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. 13, 1997
Filed:
May. 23, 1995
Michael Callahan, New York, NY (US);
John K Chester, High Bridge, NJ (US);
Robert M Goddard, New York, NY (US);
Other;
Abstract
A light dimmer is provided in which semiconductor power devices for each of the polarities of an alternating current supply are coupled between the alternating current supply and a lamp load. In the course of varying average power supplied to the lamp load, the semiconductor power devices transition between an initial one and a subsequent other of substantially conductive and non-conductive power conditions. The duration of the transition by the power device is increased beyond the minimum possible duration to reduce generated EMI. Methods of restoring each power device to its initial condition, including during a subsequent half-cycle, are described.