Patent ID: 6801592
Filing Date: 2004-10-05
Classification: H03L,H04L

Abstract:
A method of retiming a digital data signal, the method comprising:deriving an internal clock signal from an external clock signal; detecting a phase or frequency difference between the internal clock signal and the external clock signal; generating a first control signal based on the phase or frequency difference between the internal clock signal and the external clock signal; detecting a phase difference between the digital data signal and the internal clock signal; generating a second control signal based on the phase difference between the digital data signal and the internal clock signal; filtering the second control signal with a first low-pass filter; combining the filtered second control signal with the first control signal to create a steering signal; filtering the steering signal with a second low-pass filter wherein the bandwidth of the second low pass filter is narrower than the bandwidth of the first low-pass filter; and adjusting a phase of the internal clock signal with respect to a phase of the digital data signal based on the filtered steering signal.