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. 04, 2003
Filed:
Mar. 21, 2002
Bruce A. Loyer, Austin, TX (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
A method and apparatus for controlling output impedance of an input/output (I/O) circuit. In one embodiment, an I/O circuit includes a first plurality of resistive elements connected in parallel and a second plurality of resistive elements connected in parallel. Each of the resistive elements includes a control terminal. The control terminal may be used to activate or deactivate the resistive element. The control terminal for each resistive element may be controlled by a control circuit, which may be configured to activate one or more of the resistive elements. Each of the resistive elements of the first plurality may be of substantially different resistances, as may be true with the second plurality of resistive elements. Due to the substantially different resistances of each of the first and second pluralities of resistive elements, the resistive step sizes for the I/O circuit remain substantially equal as additional resistive elements are activated.