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:
Sep. 04, 2018
Filed:
Jan. 30, 2017
Fairchild Korea Semiconductor Ltd., Bucheon, KR;
Dibyendu Rana, Milpitas, CA (US);
Gwanbon Koo, Bucheon, KR;
SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC, Phoenix, AZ (US);
Abstract
An active clamp flyback converter includes a low-side switch that serves as a power switch and a high-side switch that serves as a clamp switch. The high-side switch is operated in one of two active clamp switching modes, which is selected based on load condition. In a complementary active clamp mode, the switching frequency of the low-side switch is decreased as the load increases. In a modified active clamp mode, the high-side switch is turned on in a same switching cycle first by zero voltage switching (ZVS) and second by quasi-resonant switching (QRS), with a QRS blanking time being increased as the load decreases. A ZVS delay time and dead time between switching are adaptively set based on a duty cycle of the low-side switch. The output voltage of the active clamp flyback converter is sensed from an auxiliary voltage of an auxiliary winding of the transformer.