A semiconductor device with a clock control circuit that outputs an internal clock signal configured by delaying external clock signals based on at least a feedback clock signal; a plurality of output buffers that output data in synchronization with the internal clock signal; an output replica that is a replica of the output buffers and that generates the feedback clock signal in synchronization with the internal clock signal and supplies the feedback clock signal to the clock control circuit; and a clock tree that receives the internal clock signal from the clock control circuit and transmits the internal clock signal to the plurality of output buffers and the output replica such that signal line are substantially equal to one another.