Patent ID: 7564744
Filing Date: 2009-07-21
Classification: G11B

Abstract:
1. A reproducing apparatus in which a first reproduction signal and a second reproduction signal are simultaneously obtained by a plurality of reading means from a disc-shaped recording medium on which data of a high-transfer rate and data of a low-transfer rate have been recorded, comprising: signal layout converting means for time division multiplexing said first reproduction signal and said second reproduction signal and arranging them; sync adjustment information forming means for forming sync adjustment information, which is optimum to each reproduction signal from said first reproduction signal and said second reproduction signal, based upon the transfer rate of each reproduction signal; waveform equalizing means for executing a waveform equalizing process to an output of said signal layout converting means; switching means for switching characteristics of said waveform equalizing means in accordance with said sync adjustment information; and a PLL for generating a clock signal according to said sync adjustment information, wherein said PLL comprises a voltage controlled oscillator, a phase comparator for phase-comparing an output of said voltage controlled oscillator or its frequency-divided output with an edge detection pulse of the reproduction signal, and a charge pump filter to which an output of said phase comparator is supplied and which forms a control voltage for said voltage controlled oscillator, and an output frequency of said voltage controlled oscillator and a pulse width of said edge detection pulse are controlled on the basis of switching information of heads and linear velocity information as said sync adjustment information.