Delay locked loop

The invention provides a delay locked loop comprising a first delay chain, a phase detector, a remainder chain and a remainder chain controller. The remainder chain is connected to the first delay chain to form a second delay chain. A remainder code input end of the reminder chain is used for a remainder code sent from the reminder chain controller at a coarse turning stage, and the reminder chain is used for regulating the remainder step of the reminder chain according to the reminder code. The input end of the second delay chain receives an input clock signal, the output end of the second delay chain is connected with a signal input end of the phase detector, and thus, the coarse tuning step of the second delay chain is subjected to step auxiliary delay according to the reminder step so that a clock signal output by the second delay chain is subjected to step delay by taking the reminder step as the delay unit. The input end of the reminder controller is connected with the output end of the phase detector, so that the reminder code is sent according to the phase difference output by the phase detector. The delay locked loop can solve the problem of error locking that is easily caused in use of the conventional delay locked loop and then can improve accuracy of orthogonal clock signals.