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. 20, 1987
Filed:
Sep. 21, 1984
James P Hamley, Mill Creek, WA (US);
Other;
Abstract
The input stage to an audio amplifier comprises a complementary-symmetry, differential amplifier pair which drives an intermediate voltage gain stage comprised of a complementary-symmetry, cascode differential amplifier pair. The intermediate stage provides signal drive and bias to the output power amplifier stage, which is preferably a bridged configuration. Control circuitry produces a composite bias signal which is the summation of a static bias signal and a dynamic bias signal. The bias control signal is coupled to the bias control circuit through an optical coupler, and a dynamic class A bias is achieved. Negative feedback for the amplifier is provided by a differential amplifier which has its differential inputs connected to the load terminals, thereby placing any connecting cable between the amplifier and load within the corrective feedback path.