PLL CIRCUIT AND RECORDING AND REPRODUCING DEVICE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To solve the problem such that stable search operation is not obtained because behavior of a phase locked loop(PLL) is disturbed by influence of noises at track crossing. SOLUTION: In a tape recording and reproducing device adopting a partial response maximum likelihood(PRML) system, a level judging circuit 34 which detects that a head output level (signal level) turns into a fixed level or below at the track crossing of high-speed search is provided in a PLL circuit 30 to function as a clock recovery circuit, and PLL operation is held by applying holding to a loop filter 32 by the judged output.