Patent ID: 6798698
Filing Date: 2004-09-28
Classification: G11C

Abstract:
A non-volatile semiconductor memory card comprising:an electrically erasable and programmable non-volatile semiconductor memory device; a controller unit configured to control the memory device; and a terminal configured to connect the memory device to an external device, wherein the memory device comprises: a NAND cell unit comprising a plurality of memory cells connected in series; an erase circuit for applying an erase voltage to all memory cells of said NAND cell unit to erase data from all memory cells of said NAND cell unit; a soft-programming circuit for applying a soft-program voltage to all memory cells of said NAND cell unit, the soft-program voltage having a polarity opposite to a polarity of the erase voltage; and a programming circuit for applying a program voltage to any selected one of the memory cells, applying a first voltage to at least one of two memory cells adjacent to said any selected one of the memory cells, and applying a second voltage to the remaining memory cells of said NAND cell unit, thereby to program data into said any selected one of the memory cells.