Patent ID: 7603095
Filing Date: 2009-10-13
Classification: H03L

Abstract:
1. An apparatus of switching intervals, the apparatus comprising: a coarse calibration unit, generating a plurality of coarse intervals, wherein a predetermined phase angle is divided by the number of the coarse intervals; a fine calibration unit adapted to the coarse calibration unit and having a plurality of delay cells coupled to the coarse interval for adjusting a feedback signal to be aligned to a reference signal; a phase detector adapted to the fine calibration unit, detecting a phase difference between the feedback signal and the reference signal; and a controller, controlling the coarse calibration unit and the fine calibration unit to align the feedback signal to the reference signal according to a phase difference between the feedback and the reference signals; wherein each delay cell represents a fine interval for dividing the coarse interval into a plurality of smaller intervals, a predetermined set of fine intervals is used to cover one coarse interval, and a range of the predetermined set of fine intervals is larger than that of one coarse interval, the controller switches the feedback signal from a current coarse interval into another coarse interval when the predetermined set of fine intervals is used up before the feedback signal is aligned to the reference signal.