SEMICONDUCTOR MEMORY DEVICE, METHOD FOR PROTECTING PREDETERMINED MEMORY ELEMENT, AND PORTABLE ELECTRONIC DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor memory device equipped with an easily miniaturized nonvolatile memory element, and a portable electronic device.

SOLUTION: This semiconductor memory device is provided with a memory cell array 21 in which a plurality of memory elements 1 are arrayed, and a write state machine 32. The memory element 1 is provided with a gate electrode 104 formed through a gate insulating film 103 on a semiconductor layer 102, a channel area arranged below the gate electrode 104, the diffusion areas 107ab of conductive types reverse to that of the channel area on both sides of the channel area, and a memory function body 109 having the function of holding charges on both sides of the gate electrode 104. The write state machine 32 is capable of selectively preventing the data writing or erasing of the memory element in a predetermined range in response to a locking signal.

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