MULTI PHASE DETECTOR

摘要

PURPOSE: An apparatus for detecting multi-phase is provided to reduce a locking time by detecting phase differences between an external clock and an internal clock and transferring the phase differences to DLL(delay locked loop) circuit. CONSTITUTION: The multi phase detector comprises a preset phase detector(10) for detecting phase differences between an external clock and an internal clock before operating a DLL; and an initial clock selecting controller(20) for initializing a clock selecting signal so as to select corresponding clock source from predetermined multiple clock sources through the preset phase detector(10) and performing a delay compensation from the selected clock source. The preset phase detector(10) is composed of a plurality of rising edge triggered D flip-flop(12-18).