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:
Aug. 11, 2020
Filed:
May. 23, 2019
Apple Inc., Cupertino, CA (US);
Bogdan T. Bucheru, Austin, TX (US);
Apple Inc., Cupertino, CA (US);
Abstract
A direct feedback isolated power converter can include a transformer with primary, secondary, and bias windings. A main switch can selectively enable and disable current flow through the primary winding. A controller coupled to the bias winding may be configured to generate a gate drive signal for the main switch responsive at least in part to free ringing of the transformer. The controller may detect the free ringing via the bias winding. An auxiliary switch coupled across the secondary winding may be configured to selectively short circuit the secondary winding, responsive to feedback circuitry, to control when free ringing is established. The feedback circuitry may include a proportional, proportional integral, or proportional-integral-derivative control loop, a hysteretic control loop, or other controller type. The controller may operate at a variable or fixed frequency. The direct feedback isolated power converter may be a flyback converter or other type of isolated converter.