A semiconductor device includes a latch data generation circuit and a column path circuit. The latch data generation circuit extracts pattern data from external signals and generates latched data from the extracted pattern data, when the semiconductor device enters a pattern input mode. The column path circuit stores the latched data when a write command is inputted in the pattern input mode and generates mode data from the latched data stored in the column path circuit after a write latency elapses from a point of time that the write command is inputted.