Patent ID: 7360049

Claim:
A nonvolatile semiconductor memory device comprising: at least one memory block made of a plurality of nonvolatile memory cells; and a password protection function in which data cannot be read out from a part of the memory block or the entire memory block without a cancel operation using a password, wherein the password protection function is enabled or disabled based on a first and second state specified values such that when both of the first and second state specified values are in a set state, the password protection function is enabled and when at least the second specified value is in a reset state, the password protection function is disabled, and the first state specified value maintains a previous state and the second state specified value follows the state of the first state specified value in response to a predetermined operation of the nonvolatile semiconductor memory device, and the cancel operation to shift the second state specified value to the reset state can be performed only when the password is inputted correctly.