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:
Oct. 31, 2006
Filed:
Mar. 26, 2003
Alan W. Grattan, Santa Cruz, CA (US);
William F. Fabry, Felton, CA (US);
Alan W. Grattan, Santa Cruz, CA (US);
William F. Fabry, Felton, CA (US);
Plantronics, Inc., Santa Cruz, CA (US);
Abstract
The present invention provides a solution to the needs described above through a microphone PCB with an integrated filter. The invention provides for an electret microphone assembly. The microphone assembly includes a multilayer printed circuit board. A field effect transistor with a gate is coupled to the electret microphone. The field effect transistor drain is coupled to provide audio frequency output to an audio output node, and the field effect transistor source is coupled to a ground. A first end of a resistor is coupled to the drain of the field effect transistor and the second end is coupled to a filter. The filter attenuates unwanted electromagnetic interference associated with a radio frequency transmitter. The filter includes a filter capacitor made of a ground layer coupled to ground within the multilayer printed circuit board, an active layer within the multilayer printed circuit board coupled to the second end of the resistor, and a dielectric layer disposed between the ground layer and the active layer. The filter further includes a first and second inductor comprising vias coupled to the active layer within the printed circuit board.