MECHANISMS FOR BUILT-IN SELF REPAIR OF MEMORY DEVICES USING FAILED BIT MAPS AND OBVIOUS REPAIRS

摘要

A method of self-testing and self-repairing a random access memory (RAM) is includes collecting failure data of the RAM with redundant rows and columns, wherein the failure data of all failed cells of the RAM are stored in two failure bit map (FBM) data structures. The method further includes performing obvious repair of failed cells during the collecting of the failure data and analyzing the failure data in the two FBM data structure to determine repair methods. The method further includes repairing failed cells of the RAM by using the redundant rows and columns.