Disk reproducing device, a disk reproducing method, a disk rotation control method, and a regenerative clock signal generating device

A disk reproducing device comprising:

• regenerative clock signal generating means for extracting a regenerative clock signal from reproduced data;
• demodulation means for demodulating the reproduced data in accordance with the regenerative clock signal, and outputting demodulated data;
• synchronizing signal detecting means for detecting a synchronizing signal for signal processing from the reproduced data, and outputting a synchronization detection signal;
• data storage means for sequentially storing the demodulated data;
• write address generating means for generating a write address for said data storage means from the demodulated data;
• signal-processing clock-signal generating means for generating a clock signal for signal processing including error correction;
• signal processing means for performing signal processing on the demodulated data stored in said data storage means, in accordance with the clock signal for signal processing;
• dividing means for dividing a frequency of the clock signal for signal processing by a predetermined number, and outputting a frequency-divided signal;
• read address generating means for generating a read address for reading out the demodulated data from said data storage means, in accordance with the frequency divided signal;
• address comparison means for comparing the write address with the read address, and outputting an address comparison error signal;
• and
• address reset means for simultaneously setting the write address and the read address to a predetermined value, said signal-processing clock-signal generating means generating the clock signal for signal processing on the basis of the address comparison error signal.

A regenerative clock signal generating device comprising:

• a phase comparator which detects a phase difference between two signals;
• a phase/voltage converter which converts the phase difference into a voltage;
• a voltage controlled oscillator which generates a regenerative clock signal in accordance with a phase conversion voltage which is converted by said phase/voltage converter;
• reference signal generating means for generating two signals having a predetermined phase difference;
• signal switching means for switching over two input signal of said phase comparator;
• and
• voltage supervisory means for changing a property of said phase/voltage converter in accordance with an output voltage of said phase/voltage converter, said signal switching means having a configuration in which a case where two output signals of said reference signal generating means are selected, and a case where reproduced data and the regenerative clock signal are selected are switched over, and having:
• a property adjustment mode in which the two output signals of said reference signal generating means are phase-compared with each other and the property of said phase/voltage converter is changed in accordance with the phase conversion voltage;
• and a clock signal generation mode in which the reproduced data and the regenerative clock signal are phase-compared with each other, thereby generating a regenerative clock signal having a predetermined phase relationship with respect to the reproduced data.