Electronic digital logic circuitry – Clocking or synchronizing of logic stages or gates
Reexamination Certificate
2005-03-29
2005-03-29
Tan, Vibol (Department: 2819)
Electronic digital logic circuitry
Clocking or synchronizing of logic stages or gates
C326S037000, C327S276000, C327S277000, C327S299000
Reexamination Certificate
active
06873187
ABSTRACT:
An electronic circuit includes delay selection units each associated with a flip-flop or other circuit element. The delay selection unit for a given one of the circuit elements is coupled between a source of a clock or other signal and a corresponding input of the circuit element, and is controllable to provide one of a number of selectable delays for the signal. One or more of the delay selection units are controlled so as to select a particular one of the selectable delays for each of the units. In an illustrative embodiment, the particular delays may be determined at least in part based on the solution of an integer nonlinear program in which the plurality of delays for a given one of the delay selection units are arranged substantially in a monotonically increasing manner and each of at least a subset of the selectable delays for the given one of the delay selection units is specified by upper and lower bounds on the corresponding delay. The integer nonlinear program comprises a system of monotone difference constraints on finite integer ranges, and is solvable utilizing a modified Bellman-Ford algorithm.
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Andrews William
Britton Barry
Chen Xiaotao
Fishburn John P.
Scholz Harold
Lattice Semiconductor Corporation
Tan Vibol
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