The present invention is directed to a semiconductor device having a non-volatile memory cell 18, and a readout circuit 102 which reads out data of the memory cell 18 DATA using a first data DATA1 obtained by sensing a first reference level REF1 for reading out the data of the memory cell 18 and a level of the memory cell 18 CORE and using a second data DATA2 obtained by sensing a second reference level REF2 for reading out the data of the memory cell 18 and the level of the memory cell 18 CORE, and to a controlling method for the same.