CLOCK ADJUSTING DEVICE IN DATA REPRODUCING SYSTEM

摘要

PROBLEM TO BE SOLVED: To guarantee the sampling of a reproduced signal from a recording medium in an appropriate phase by obtaining a sampling value used for the reproduction of recorded data conforming to viterbi decoding algorithm, detecting a synchronizing point of a reproduced signal, and calculating a difference value between a level of a synchronizing point of a reproduced signal decided by a partial response characteristic and a sampling value. SOLUTION: A branch metric calculation unit BM 101 calculates a branch metric value corresponding to difference between an expected value being obtainable in a reproduced signal depending on a partial response characteristic and a sampling value. An ACS unit 102 adds a branch metric value and a path metric value one clock before being stored in a path metric memory PMM 103, compares values after addition two by two, and selects a smaller value. The almost surest data can be detected by shifting successively to data corresponding to a path in which a path metric value is always is made the minimum.