A semiconductor device includes an internal circuit to perform a predetermined function at a plurality of different supply power voltages, a power supply voltage region detector to detect a supply power voltage to output a detection signal, a latch to store the signal output from the power supply voltage region detector and output the stored signal as a power supply voltage region signal, and a reset circuit to generate a reset signal to perform a predetermined reset operation on the internal circuit. The latch stores the output signal from the power supply voltage region detector just after the reset operation for the internal circuit is released, and the internal circuit changes an internal setting according to the power supply voltage region signal output from the latch.