摘要 |
A DLL circuit includes a multiphase clock signal generating unit configured to produce a plurality of multiphase clock signals by delaying a reference clock signal for a unit delay time and to produce an enable signal that is enabled when one of the plurality of the multiphase clock signals synchronizes with the reference clock signal at a frequency, and a multiphase clock signal selecting unit configured to delay one of the plurality of the multiphase clock signals for a predetermined time in response to a first control signal, to compare a phase of a delayed multiphase clock signal with a phase of the reference clock signal, and to output one of the plurality of the multiphase clock signals as a delayed clock signal, wherein a phase of the delayed clock signal synchronizes with the phase of the reference clock signal when the enable signal is enabled.
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