摘要 |
One delay locked loop circuit embodiment includes a delay line system configured to generate a clock output signal by adding a delay line system time delay to a clock reference signal, a phase detector, a shift register, and a control unit. The delay line system includes a coarse delay line to adjust the delay line system time delay by remote coarse-shifting, a phase selector configured to adjust the delay line system time delay by local coarse-shifting output signals from a series of local coarse delay units, and a phase mixer to adjust a particular time delay of the clock output signal by fine-shifting. The phase mixer does not receive the clock reference signal. The phase detector detects a phase difference between the clock reference signal and the clock output signal. The shift register controls the remote coarse-shifting, and the control unit controls the local coarse-shifting, based on the phase difference.
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