Disclosed herein is a device that includes a first buffer circuit coupled between a first power supply line and a data terminal and a second buffer circuit coupled between a second power supply line and the data terminal. First and second internal data signals complementary to each other are supplied to a level shifter, thereby third and fourth internal data signals complementary to each other are generated by changing amplitude values of the first and second internal data signals. The first and the second buffer circuits are controlled based on the third and fourth internal data signals such that one of the first and second buffer circuits turns on and the other of the first and second buffer circuits turns off.