Column redundancy high area efficiency is flexible for non-volatile memory

摘要

The present invention provides a nonvolatile memory that can remove the defective column in the memory cell array. According to another aspect of the present invention, it is possible redundant column alternative, replace the column is removed. Both these processes are transparent to the outside, in a way that does not need to be managed from an external host controller or attached memory-This is performed in memory. It can be maintained in memory for the inventory of defective column. In power-up, to retrieve the defective column using the list of bad columns. The memory, redundant columns of many that may be used to replace the defective column also may contain.