A latency circuit comprises a latency control block, an internal read command generator, and a latency signal generation unit. The latency control block generates a plurality of first control clocks by delaying a delay sync signal generated based on an external clock, and generates a second control clock having a margin with respect to a read command decoded based on the delay sync signal. The internal read command generator samples the second control clock using the decoded read command and generates an internal read command based on a sampled second control clock. The latency signal generation unit generates a latency signal based on a shifting operation performed on the internal read command using the plurality of first control clocks.