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:
Jan. 05, 1999
Filed:
Oct. 06, 1997
Andrew Cyril Krochmal, Plymouth, MI (US);
Ford Motor Company, Dearborn, MI (US);
Abstract
A high output power is obtained for an audio power amplifier using an amplifier circuit topology wherein channels or stages of a multi-channel class AB monolithic integrated circuit are paralleled in order to drive a low impedance dual voice coil speaker. The stages are paralleled by connecting their outputs through isolation resistors. These resistors prevent the differences in output bias voltages from resulting in a short circuit from power to ground. In addition, the resistors are sufficiently small to achieve the correct speaker damping factor, yet large enough to prevent excessive quiescent current. The separate amplifier channels or stages are paralleled through isolation resistors which increases current drive resulting in a higher output power to the loud speaker.