| CPC H04L 7/0054 (2013.01) | 18 Claims |
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1. A method for comparing a first clock signal with a second clock signal, the method comprising:
generating a first periodic signal phase dependent upon the first clock signal;
generating a second periodic signal phase dependent upon the first clock signal and phase offset from the first periodic signal;
sampling the first and second periodic signals timed to a sequence of edges of the second clock signal to produce a sequence of states, each state including concurrent samples of the first and second periodic signals, wherein the sequence of states repeats a pattern of the states when the first clock signal is phase aligned with the second clock signal;
evaluating state transitions in the sequence of states; and
indicating a phase misalignment between the first clock signal and the second clock signal responsive to a deviation from the pattern of the states.
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