Semiconductor integrated circuit device responsive to clock signals having different amplitudes

摘要

A buffer 6 operating in response to an amplitude level of a clock signal is provided in a semiconductor integrated circuit device such as, a gate array. By selectively applying clock signals of different amplitude corresponding to operation modes, the buffer 6 operates selectively. Therefore, for example, the designation of a test mode can be detected by the buffer 6. As a result, it is not necessary to provide a terminal for externally receiving a test mode signal.