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:
Feb. 02, 2021
Filed:
Nov. 29, 2018
Applicant:
Apple Inc., Cupertino, CA (US);
Inventors:
Roderick B. Hogan, San Francisco, CA (US);
Michael B. Nussbaum, Santa Cruz, CA (US);
Todd K. Moyer, Portland, OR (US);
Assignee:
APPLE INC., Cupertino, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03F 1/26 (2006.01); H03F 3/68 (2006.01); H03F 3/217 (2006.01); H03F 3/185 (2006.01); H04R 3/00 (2006.01);
U.S. Cl.
CPC ...
H03F 3/2173 (2013.01); H03F 1/26 (2013.01); H03F 3/185 (2013.01); H04R 3/00 (2013.01); H03F 2200/03 (2013.01); H03F 2200/33 (2013.01);
Abstract
An audio amplifier has an analog current source amplifier and a class D amplifier. The analog current source amplifier is active in a first mode to drive a speaker when an audio signal has smaller amplitude. The class D amplifier is active in a second mode to drive the speaker when the audio signal has larger amplitude. Other aspects are also described and claimed.