Semiconductor storage device

A semiconductor storage device having a security function for imposing limitation on data rewriting, the semiconductor storage device comprising:

• at least one non-volatile memory cell array block which is capable of receiving concurrent electrical erasure;
• at least one memory region, each one of said at least one memory region being provided in the at least one memory cell array block, for storing a security release key;
• at least one non-volatile storage means for storing a security registration lock corresponding to each of the at least one memory cell array block;
• a determination circuit for comparing a value which is generated based on the security release key against a value which is generated based on the security registration lock to determine whether or not to grant release of the security function;
• and
• a memory cell array data output switching circuit for, when an output signal from the determination circuit indicates a matching result of comparison between the value which is generated based on the security release key and the value which is generated based on the security registration lock, permitting data which is read from a corresponding one of the at least one memory cell array block to be externally output.