NONVOLATILE SEMICONDUCTOR MEMORY DEVICE USING NONVOLATILE STORAGE ELEMENTS TO WHICH DATA CAN BE WRITTEN ONLY ONCE

摘要

A nonvolatile semiconductor memory device includes a nonvolatile storage element to which data is inhibited from being rewritten, a read operation control circuit which captures a read operation instruction signal in synchronization with an external input clock, and a write operation control circuit to which a write operation instruction signal is input asynchronously with the external input clock. The read operation instruction signal gives an instruction to start a read operation to read data out of the nonvolatile storage element, and the write operation instruction signal gives an instruction to start a write operation to write data to the nonvolatile storage element. The device further includes a reset circuit which resets an operation of the read operation control circuit upon receiving the write operation instruction signal.