NONVOLATILE SEMICONDUCTOR MEMORY DEVICE

摘要

PROBLEM TO BE SOLVED: To realize a password-unlock function while an increase in the chip area is suppressed as much as possible.

SOLUTION: A nonvolatile semiconductor memory has a function to conduct verifying for write in data from the outside. The memory includes: a memory cell array 1 in which memory cells are arranged in a matrix manner and a password storage region is provided to store a password; an input buffer 11 which is used to receive data inputted from the outside; a first holding circuit which holds the input password being inputted into the input buffer 11 or write in data; a verify sense amplifier 4 which detects the readout password from the password storage region or the readout data from the memory cell array 1 during a verify operation; and a coincidence judgment circuit 300 which judges whether the inputted password and the readout password are matched with each other or not or the write in data and the readout data are matched with each other or not.

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