Shielded bit line sensing scheme for nonvolatile semiconductor memory

摘要

A memory incorporates a shield bit line reading system for fixing one of two bit lines disposed adjacent to each other to a shield potential and reading data to the other bit line. Selected bit lines are precharged to a power source potential, and then brought to a floating state. The shield bit lines are fixed to the power source potential. A period in which the power source potential is applied to the selected bit lines and a period in which the power source potential is applied to the shield bit lines are the same. A source line decoder applies the power source potential to sources of NAND cell units connected to selected bit lines and applies a ground potential to sources of NAND cell units connected to shield bit lines. Then, an output of data is produced from the memory cell to the selected bit lines.