A circuit including a first circuit configured to receive an input signal and first, third and fifth phase clocks of a clock, and generate a first early signal indicating the clock is earlier than the input signal and a first late signal indicating the clock is later than the input signal. The circuit further includes a second circuit configured to receive an input signal and second, a fourth and sixth phase clocks of the clock, and generate a second early signal indicating the clock is earlier than the input signal and a second late signal indicating the clock is later than the input signal. The circuit further includes a third circuit configured to generate a first increase signal. The circuit further includes a fourth circuit configured to generate a first decrease signal.