Constant current read mode or constant current data retention mode nonvolatile memory device

A non-volatile semiconductor memory circuit, comprising:

• a non-volatile memory cell having an erase state in which a threshold voltage is low and a write state in which the threshold voltage is high to thereby store data;
• a constant current circuit connected in series with the non-volatile memory cell;
• and
• a connection point between the non-volatile memory cell and the constant current circuit being set to be an output;
• wherein, in a reading mode or a retention mode, in which a voltage is applied to the non-volatile memory cell, the following relationship is satisfied:
• IWRITE<ICONST<IERASE,
• where a saturation current flowing through the non-volatile memory cell in the erase state is represented by IERASE, a saturation current flowing through the non-volatile memory cell in the write state is represented by IWRITE, and a constant current provided from the constant current circuit is represented by ICONST.