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:
Jun. 16, 1998
Filed:
Nov. 21, 1996
Gordon L Irwin, Bothell, WA (US);
Patrick H Quilter, Laguna Beach, CA (US);
QSC Audio Products, Inc., Costa Mesa, CA (US);
Abstract
A power supply of the high frequency series resonant mode family for supplying power to audio amplifiers includes half and full bridge variations and supplies all of the required rail voltages while maintaining fixed frequency resonant operation throughout all combinations of loading of the amplifier outputs without the need for a large explicit resonant inductance. The elimination of switching loss enables the use of power supply switching devices optimized for low conduction loss, further improving performance under high current conditions. The power supply frequency is fixed by an oscillator of sufficient precision to ensure that the beat frequency that will result from heterodyning of the residual switching frequency noise between two identical but separate power supplies will be in the infrasonic range. Protection circuitry is provided to limit peak switch currents during the start up interval. The power supply and power amplifier protection functions are interlinked, resulting in simplified protection against short and long term current overloads, thermal overloads, output load shorts, and amplifier faults leading to DC outputs. The intended application is the reproduction of audio signals, which have a high crest factor, requiring the ability to deliver high short term power levels from a given set of components.