US Patent 7644386 Redundancy structures and methods in a programmable logic device

An embodiment of the present invention provides a programmable logic device (“PLD”) including a redundancy architecture adapted to selective route signals via first or second staggered vertical lines. Other embodiments provide configuration logic and programs for determining routing selections. Other embodiments provide proximate grouping of vertical lines driven from a same row. Other embodiments provide definition of spare row locations once defective row locations are known.