I/O divided column redundancy scheme for high-speed DRAM with multiple I/Os

A novel I/O divided column redundancy (IDCR) scheme that can improve the ef fectiveness of repair and minimise the overhead of the die area is presente d. The IDCR scheme has greater flexibility than conventional schemes in mul tiple I/O DRAMs. Since an IDCR can share neighbouring redundant column line s (RCLs), the RCLs of neighbouring I/O blocks can be used to repair the def ective column lines of a self-block. This work also shows that the IDCR sch eme improves the data access speed of normal column lines or redundant colu mn lines by reducing the data bus loading.