Configurable logic element with ability to evaluate five and six input functions

Patent 5920202 Issued on July 6, 1999. Estimated Expiration Date:

April 4, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventors

Application

No. 835088 filed on 04/04/1997

US Classes:

326/39, Array (e.g., PLA, PAL, PLD, etc.)326/37, MULTIFUNCTIONAL OR PROGRAMMABLE (E.G., UNIVERSAL, ETC.)326/41Significant integrated structure, layout, or layout interconnections

Examiners

Primary: Tokar, Michael
Assistant: Chang, Daniel D.

Attorney, Agent or Firm

Cartier; Lois D., Young; Edel M.

Foreign Patent References

0461798A2 EP. 06/13/1991
0451798A2 EP. 06/13/1991
0 630 115 A2 EP. 12/13/1994
0748049A2 EP. 12/13/1996
0746107A2 EP. 12/13/1996
2300951 GB. 11/13/1995
2 295 738 GB. 06/13/1996
WO 93/05577 WO. 08/13/1992
WO9410754 WO. 05/13/1994

International Classes

G06F 007/38
H03K 019/173

Abstract

The invention provides a Configurable Logic Element (CLE) preferably included in each of an array of identical tiles. A CLE according to the invention has four function generators. The outputs of two function generators are combined with a fifth independent input in a five-input-function multiplexer or function generator to produce an output that can be any function of five inputs, or some functions of up to nine inputs. The outputs of the other two function generators are similarly combined. The outputs of the two five-input-function multiplexers or function generators are then combined with a sixth independent input in a first six-input-function multiplexer or function generator, and with a different sixth independent input in a second six-input-function multiplexer or function generator. The two six-input-function multiplexers or function generators therefore produce two outputs of which one can be any function of six inputs; the other output can be any function of six inputs provided that five inputs are shared between the two 6-input functions. Some functions of up to nineteen inputs can also be generated in a single CLE.

Other References

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