A semiconductor device includes: a multi-level receiver including N sense amplifiers and a decoder decoding an output of the N sense amplifiers, each of the N sense amplifiers receiving a multi-level signal having M levels and a reference signal (where M is a natural number, higher than 2, and where N is a natural number, lower than M); a clock buffer receiving a reference clock signal; and a clock controller generating N clock signals using the reference clock signal, inputting the N clock signals to the N sense amplifiers, respectively, and individually determining a phase of each of the N clock signals using the output of the N sense amplifiers.