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:
Aug. 08, 2017
Filed:
Jun. 26, 2014
Apple Inc., Cupertino, CA (US);
Roderick B. Hogan, San Francisco, CA (US);
Girault W. Jones, Los Gatos, CA (US);
Nathan A. Johanningsmeier, San Jose, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
A method for audio signal processing, where an audio amplifier drives a load through a connector, using 1) an input audio signal, and 2) a signal from a return pin of the connector. Output headroom of the audio amplifier is automatically detected, while the amplifier is driving the load. A variable resistor circuit that is coupled to provide variable resistance between the return pin of the connector and a ground plane, is automatically adjusted, in response to the detected output headroom of the amplifier. Other embodiments are also described and claimed.