PURPOSE: To actuate a sense amplifier circuit on the basis of a programmed value by making the amplitude range of a real signal inputted to the sense amplifier circuit through a bit line coincide with the amplitude range of an input optimizing the effects such as the amplification factor of the sense amplifier circuit.

CONSTITUTION: Information read out from an optional memory cell in a memory cell array is amplified by the sense amplifier circuit 3 through the bit line. The sense amplifier circuit 3 is programmed so that its effects such as the amplification factor are maximized by the amplitude range of a signal inputted to the sense amplifier circuit 3 itself. Since power supply potential is supplied from the same power supply line 6 to the sense amplifier circuit 3 and a bit line pull-up transistor 2, the amplitude range of the signal inputted to the sense amplifier circuit 3 through the bit line coincides with the amplitude range of the input maximizing the effects of the sense amplifier circuit 3 without influence due to a wire resistance. Thus, the sense amplifier circuit 3 executes its optimum operation as designed.