Method of programming, erasing, and reading block lock-bits and a master lock-bit in a flash memory device

摘要

A method of writing to flash memory cells in a flash memory device. The flash memory device includes a first memory array and a second independent memory array. The first memory array includes memory blocks each having a memory cell. The second independent memory array includes block lock-bits each corresponding to one of the memory blocks. The method of writing to a memory cell in one of the memory blocks of the first memory array includes the steps of issuing a command to write to the memory cell, determining if a corresponding block lock-bit in the second independent memory array is set, and writing to the memory cell if the corresponding block lock-bit is not set.