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. 08, 2005
Filed:
Jun. 18, 2003
Wouter Groothedde, Almere, NL;
Eric Antonius Maria Klumperink, Lichtenvoorde, NL;
Bram Nauta, Borne, NL;
Rudolphe Gustave Hubertus Eschauzier, Bergschenhoek, NL;
Nico Van Rijn, Katwijk, NL;
Wouter Groothedde, Almere, NL;
Eric Antonius Maria Klumperink, Lichtenvoorde, NL;
Bram Nauta, Borne, NL;
Rudolphe Gustave Hubertus Eschauzier, Bergschenhoek, NL;
Nico van Rijn, Katwijk, NL;
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A two-wire interface for a digital microphone circuit includes a power line and a ground line. The interface utilizes the ground line as a 'voltage active line' to transmit both clock and data signals between the digital microphone circuit and a receiving circuit. The digital microphone circuit detects the clock signal on the voltage active line and uses the detected clock signal to operate an ADC to provide digital data. The digital data is used to selectively drive current back to the receiving circuit over the voltage active line. The receiving circuit detects the transmitted data by monitoring the voltage associated with a line termination. The impedance associated with the line termination is switched by the receiver circuit to modulate the clock signal on the voltage active line.