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:
Nov. 10, 2009
Filed:
Sep. 29, 2004
Ching Shyu, San Jose, CA (US);
Robert M. Khamashta, Los Gatos, CA (US);
Robert J. Bernardi, Scotts Valley, CA (US);
Ching Shyu, San Jose, CA (US);
Robert M. Khamashta, Los Gatos, CA (US);
Robert J. Bernardi, Scotts Valley, CA (US);
Plantronics, Inc., Santa Cruz, CA (US);
Abstract
Systems and methods for variably and/or shiftably limiting signal output are disclosed. The system may include an attenuation circuit having an attenuation network activated by a source signal crossing a threshold to attenuate the source signal and a resistive element such as resistors bridging between the attenuation circuit input and output for variably attenuating the source signal. The attenuation circuit may be activated by a switch such as transistors. To shift the limiting threshold, the system may include a circuit to shift the activating threshold, the circuit having a control voltage source such as DC voltage source coupled to the attenuation network. The threshold shifting circuit may be configured to selectively increase the threshold during music listening and to be inactive during voice applications. The system may be incorporated in a headset adapter or a headset receiver.