Built-in self-repair techniques for content addressable memories

In this paper, we propose block-level replacement techniques for content-addressable memories. The CAM array is first divided into row banks and column banks. Then, for each divided array (the overlapped CAM cells of a row bank and a column bank), two redundant row blocks are added and reconfiguration is performed at the block level instead of the conventional word level. According to simulation results, the hardware overhead is 1.31% for a 1024 × 1024-bit CAM array. We also analyze the repair rates of our approaches. It is also found that our approach will achieve higher repair rates.