A circuit includes a first phase-adjustment circuit adjusting phases of rising edges and falling edges of an original signal, and a phase-delay circuit receiving a phase-adjusted signal from said first phase-adjustment circuit and generating a delay signal by delaying said phase-adjusted signal by a predetermined phase amount. The circuit further includes a phase-comparison circuit comparing phases of edges between said phase-adjusted signal and said delay signal so as to control said first phase-adjustment circuit such that said phases of edges satisfy a predetermined phase relation.