A plurality of ferroelectric memory cells is arrayed. One terminal of each memory cells arrayed in the same column is connected in common to a first bit line. A gate of a transistor of memory cells arrayed in the same row is connected in common to a word line. The other terminal of each of memory cells arrayed in the same column or the same row is connected in common to a cell plate line. A second bit line is connected with a reference voltage supply circuit. The first and second bit lines are connected with a data read circuit. The data read circuit includes a sense amplifier and a current mirror circuit having a pair of current input node connected to the first and second bit lines, and carrying the same current flowing through one of the first and second bit line to the other bit line.