Source: http://www.google.com/patents/US8217678?dq=5631832
Timestamp: 2013-12-20 18:02:22
Document Index: 705842261

Matched Legal Cases: ['Application No. 200410033018', 'Application No. 201010142831', 'Application No. 200410033018', 'Application No. 04250564', 'Application No. 04250564', 'Application No. 2004']

Patent US8217678 - Fracturable lookup table and logic element - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsA logic element includes memory elements, multiplexers, and controls. The multiplexers are arranged in levels including a highest level of multiplexers with inputs connected to the memory elements and outputs connected to inputs of a next-to-highest level of multiplexers and a first level of multiplexers...http://www.google.com/patents/US8217678?utm_source=gb-gplus-sharePatent US8217678 - Fracturable lookup table and logic elementAdvanced Patent SearchPublication numberUS8217678 B1Publication typeGrantApplication numberUS 12/834,404Publication dateJul 10, 2012Filing dateJul 12, 2010Priority dateFeb 10, 2003Also published asUS7800401Publication number12834404, 834404, US 8217678 B1, US 8217678B1, US-B1-8217678, US8217678 B1, US8217678B1InventorsDavid Lewis, Bruce Pedersen, Sinan Kaptanoglu, Andy L. LeeOriginal AssigneeAltera CorporationExport CitationBiBTeX, EndNote, RefManPatent Citations (60), Non-Patent Citations (34), Classifications (5) External Links: USPTO, USPTO Assignment, EspacenetFracturable lookup table and logic elementUS 8217678 B1Abstract A logic element includes memory elements, multiplexers, and controls. The multiplexers are arranged in levels including a highest level of multiplexers with inputs connected to the memory elements and outputs connected to inputs of a next-to-highest level of multiplexers and a first level of multiplexers with inputs connected to outputs of a second level of multiplexers and at least one output. The controls are connected to the multiplexers. In a first operational mode the controls determine a first-mode output at the at least one output of the first level of multiplexers, and in a second operational mode the controls determine a plurality of second-mode outputs at selected outputs of multiplexers not at the first level of multiplexers.
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of and claims priority from U.S. patent application Ser. No. 11/841,727, filed Aug. 20, 2007, titled �FRACTURABLE LOOKUP TABLE AND LOGIC ELEMENT�, which is a continuation of U.S. patent application Ser. No. 11/753,048, now U.S. Pat. No. 7,312,632, filed May 24, 2007, titled �FRACTURABLE LOOKUP TABLE AND LOGIC ELEMENT�, which is continuation of U.S. patent application Ser. No. 11/189,549, now U.S. Pat. No. 7,323,902, filed Jul. 25, 2005, titled �FRACTURABLE LOOKUP TABLE AND LOGIC ELEMENT�, which is a continuation of U.S. application Ser. No. 10/364,310, now U.S. Pat. No. 6,943,580, filed Feb. 10, 2003, titled �FRACTURABLE LOOKUP TABLE AND LOGIC ELEMENT�, all of which are incorporated herein by this reference for all purposes.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a fracturable 6-LUT (�six-input lookup table circuit) according to an embodiment of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS FIG. 7 shows a conventional 6-LUT 700 that includes four 4-LUTs 702. Each 4-LUT 702 includes sixteen memory elements and a 16:1 multiplexer that is controlled by inputs a, b, c, and d 704. Outputs from the 4-LUTs 702 provide inputs to two 2:1 multiplexers 706, each of which is controlled by input e 708. Outputs from these multiplexers provide inputs to an additional 2:1 multiplexer 710 that is controlled by input f 712 to provide a final output 714. In this way any function of six inputs z1 (a,b,c,d,e,f) can be implemented.
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