NON-VOLATILE STORAGE DEVICE

PURPOSE:To prevent a dishonest security releasing inhibiting the output of protection information, which a non-volatile storage element for a security has, by means of a signal from a pressure detecting circuit when a power voltage outside a specification is impressed. CONSTITUTION:A transistor 21 for detecting a power voltage is made into an off-condition when a power voltage Vcc is at a specification maximum value or below, and it is changed from the off-condition to an on-condition by a voltage higher than the specification maximum value and lower than the voltage at which a transistor 11 for a security in a writing condition is made conductive. Consequently, when the power voltage Vcc is raised to the specification maximum value or above, the transistor 21 for detecting the power voltage before the transistor 11 for the security in the writing condition is made conductive, and a transistor 54 for a switch is turned off. Thus, the reading of storage information to an external part can be inhibited, and the security can be prevented from being dishonestly released.