| 摘要 |
PURPOSE:To share an integrated circuit IC by using phase difference method having very high trackability when using a recording medium of low linear velocity for a recording medium of high linear velocity. CONSTITUTION:In the case of laser disk player, linear velocity is about ten times faster than a compact disk player, and for a flaw of the same size, off- track is not caused, as a time for passing the flaw section is short. For reproducing a recording medium of high linear velocity, an invalid pulse canceling circuit, that is, a phase error accumulating means is by-passed. For this purpose, the output of a phase comparator 55 is connected to a constant current circuit 56, and at the same time, connected to a buffer 59. Phase difference signals that passed the invalid pulse canceling circuit are outputted from a buffer 58, and phase difference signals of high speed response that do not pass through the invalid pulse canceling circuit are always outputted from the buffer 59. These output are connected to switching terminals through a switch S3 and switched signals are outputted from the common terminal.
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