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. 09, 2008
Filed:
Aug. 06, 2003
Douglas Gene Keithley, Boise, ID (US);
Douglas Gene Keithley, Boise, ID (US);
Avago Technologies General IP Pte Ltd, Singapore, SG;
Abstract
A method and apparatus for generating and controlling volume of a speaker of an appliance is disclosed. The appliance includes an IC chip connected to an amplifier subsystem. The IC chip includes a square-wave audio signal generator, a counter, a register, a comparator, and an AND gate. Theses components of the IC chip are used to generate modulated audio frequency square-wave signal. The modulated audio frequency square-wave signal having pulses, each pulse has a width determined by the volume control value. The modulated audio frequency square-wave signal is sent from the IC chip to the amplifier subsystem on a single connection. At the amplifier subsystem, the modulated audio frequency square-wave signal is integrated over, filtered, and amplified to drive a speaker to produce the desired sound. By adjusting the volume control value, the widths of the pulses, thus the volume of the produced sound can be controlled.