Patent ID: 7183821
Filing Date: 2007-02-27
Classification: H03L

Abstract:
1. An apparatus of controlling clock phase alignment, the apparatus comprising: a coarse calibration unit, generating a plurality of output signals, the output signals having a plurality of phase intervals therebetween, wherein a predetermined phase angle is divided by the number of the output signals to generate one of the phase intervals; a first fine calibration unit connected to the coarse calibration unit, delaying one of the output signals by coupling a programmable delay circuit to adjust a phase of a feedback signal to a phase of a reference signal; a phase detector connected to the first fine calibration unit, detecting a phase difference between the reference signal and the feedback signal and outputting an indicating signal corresponding to the phase difference between the reference signal and the feedback signal; and a controller, controlling the coarse calibration unit and the first fine calibration unit to align the feedback signal to the reference signal according to the indicating signal generated from the phase detector.