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:
Mar. 04, 2003
Filed:
Aug. 23, 2001
Douglas M. Hannan, Gray, ME (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
The present invention provides a method and apparatus for current steering for an LVDS input buffer. A current steering circuit is configured to steer current to a first node and/or a second node in response to a comparison between the input common-mode signal and a reference signal. During high input common-mode, more current is steered to the P-channel differential pair node of the input buffer as compared to the N-channel differential pair node. During low input common-mode, more current is steered to the N-channel differential pair node of the input buffer as compared to the P-channel differential pair node. The current steering reduces jitter and achieves stable output of the input buffer over process, voltage and temperature. The method and apparatus provided ensures a stabilized summation of the currents I +I and I +I by steering current into the P-channel node or N-channel node.