Modified berger codes for on-line DRAM repair strategies

For DRAM memories, multi-bit soft and hard errors are the main concern, especially when the feature size continues to decrease aggressively. As a consequence, the classical detection/correction schemes are becoming ineffective. The Berger codes are used in DRAMs to detect unidirectional errors, but produce a considerable delay when considering large memory sizes. Also, there is no correction feature for either soft or hard errors. The families of codes proposed are based on the Berger code and can be used to detect, localize and correct single or multi-bit errors at the expense of more check bits and while having a lower delay. In addition, the hardware required for the code generation and verification is discussed as well, as the hardware needed for dealing with both types of errors in on-line applications of DRAMs.