A semiconductor integrated circuit includes a first circuit and a second circuit. The first circuit is configured to divide a first pulse signal having a first duty cycle by N (where N is an integer of 2 or more), and output 2×N second pulse signals of which phases are different from each other. The first pulse signal is a pair of differential signals. The second circuit is configured to receive one or more selection signals and calculate a logical product of one of the one or more selection signals and two of the 2×N second pulse signals to generate a third pulse signal having a second duty cycle less than the first duty cycle.