Disclosed herein is a device that includes a command decoder and a latency counter. The command decoder generates a first internal command in response to a first internal clock signal. The latency counter includes: a gate control signal generation unit generating output gate signals in response to a second internal clock signal; delay circuits each receiving an associated one of the output gate signals and generating an associated one of input gate signals; and a command signal latch unit fetching the first internal command in response to one of the input gate signals and outputting the first internal command in response to one of the output gate signals. Each of the delay circuit includes a first delay element that operates on a first power supply voltage and a second delay element that operates on a second power supply voltage different from the first power supply voltage.