Column redundancy circuit with reduced signal path delay

摘要

A semiconductor memory has memory elements arranged in memory blocks with each memory block having normal columns and at least one redundant column. In the event of a normal column being found to be defective, a redundant column may be used to replace the defective column. The semiconductor memory allows a redundant column in one block to replace a defective column in another block. The memory block may also be separated into an upper and lower portion allowing the portions to individually replace upper or lower column portions from different defective columns.