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:
Dec. 29, 2009
Filed:
Jul. 01, 2005
William P. Cornelius, Los Gatos, CA (US);
Matthew K. Herndon, San Carlos, CA (US);
Ronald K. Larson, Mountain View, CA (US);
William P. Cornelius, Los Gatos, CA (US);
Matthew K. Herndon, San Carlos, CA (US);
Ronald K. Larson, Mountain View, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
A system that transmits signals through a communication channel. During operation, the system receives a sequence of bits for transmission through the communication channel. While transmitting a given bit, the system determines if the given bit has the same state as the previously transmitted bit. If so, the system uses a voltage-mode driver to drive a signal through the communication channel. Otherwise, the system uses a current source coupled to the voltage-mode driver to boost the drive-level of the voltage-mode driver. Note that the current source supplies a current to the communication channel without changing the impedance of the voltage-mode driver. In this way, the present invention compensates for frequency dependant losses in the communication channel without sacrificing impedance matching and without substantially increasing power consumption.