Delay Locked Loop

Delay locked loop according to one embodiment of the present invention is a delay lock loop for fixing the delay of the input signal and the output signal, unit to delay the input signals outputs the output signal a variable delay; Model delay unit to delay an output signal and outputs a first feedback signal; A first phase comparator for controlling the delay amount variable delay portion according to the input signal and the phase difference between the first feedback signal; Tracking operation during the pulse generation unit for generating the input signal and the second pulse signal according to a first feedback signal; Tracer pulse holding part to generate a second feedback signal by delaying the output signal of the variable delay in operation; Selecting a pulse signal or the second feedback signal generated by the tracking operation when the pulse generator to pulse selection provided as an input signal of the variable delay unit; And including in said pulse selector during tracking operation according to the phase difference between the selected signal and the output signal a second phase comparator for generating a delay control signal for controlling the delay amount of said variable delay.