JP2001256718A - Information recording and reproducing device, and revolving speed controller for information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance a recording speed at the time of a data recording to an information recording medium. SOLUTION: An edge detecting circuit 22 detects the linear velocity at the time of the rotation of an optical disk 1 to output the detection data of the linear velocity to next circuits and when a recording to the disk 1 is performed, a CAV/CLV changeover control signal generating circuit 24 generates a CAV/ CLV changeover control signal controlling the changeover of an FG signal and a reference signal for CLV based on the detection data of the linear velocity and the linear velocity setting data of a register for linear velocity setting data 21. A selector 25 selects either the FG signal or a reference signal for CLV based on the CAV/CLV changeover control signal to output it to a next circuit and a spindle revolving speed control circuit 26 controls the revolving speed of a spindle motor 2 so that the selected FG signal or the reference signal for CLV becomes to be a constant cycle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
An information recording / reproducing apparatus such as an optical disk drive for recording and reproducing information on and from a disk-shaped information recording medium such as RW, DVD-RAM, and MO; and a rotation for controlling a rotation speed of the information recording medium during recording and reproducing of information. The present invention relates to a speed control device.

[0002]

2. Description of the Related Art Information (data) is recorded on an optical disc, which is a read-only information recording medium such as a CD or DVD-ROM, so that a linear density in a recording area is constant.

Also, when data is recorded on an optical disc which is a recordable information recording medium such as a CD-R or CD-R / W, it is necessary to record the data so that the linear density in the recording area is constant. is there.

[0004] As described above, there are roughly the following two recording methods for recording data so that the linear density of data is constant in the recording area of the optical disk.

(1) A spindle motor for rotating an optical disk is controlled to rotate at a constant linear velocity (hereinafter referred to as “CLV”), and data is recorded with a write clock having a constant frequency, thereby reducing the data recording density in the recording area. A recording method for making constant (hereinafter, referred to as “CLV recording method”).

(2) The rotation of the spindle motor is controlled at a constant angular speed, that is, a constant rotation speed (hereinafter referred to as "CAV"), and the frequency of the write clock is changed in accordance with the radial position where data on the recording area is recorded. A recording method in which data is recorded to keep the recording density of data in a recording area constant (hereinafter, “CAV recording method”).

However, in the above-described CLV recording method, seeking is performed from the innermost circumference to the outermost circumference of the recording area of the optical disk, and when writing data, the rotation speed of the spindle motor is changed from the disk rotation speed at the innermost circumference to the outermost circumference. It is necessary to decelerate at a stretch to the disk rotation speed, while it is necessary to accelerate at a stretch from the outermost circumference to the innermost circumference.

Therefore, data recording must be waited for the time until the rotation of the spindle motor is stabilized (referred to as "rotation settling time"), so that the access time to the data recording location becomes longer.

In order to shorten the rotation settling time, it is necessary to provide an expensive spindle motor for generating a large torque, and the torque for shortening the rotation settling time is generated at the inner and outer circumferences of the optical disk. The larger the difference between the rotation speeds of the spindle motors is, the larger the required torque is. Therefore, there is a problem that the manufacturing cost of the information recording / reproducing apparatus is increased.

In the CAV recording method, when the spindle motor is controlled by the CAV, the write clock frequency on the outer periphery of the optical disk increases, and the signal processing system, the minimum pulse width of the write strategy at the time of recording, the media sensitivity of the optical disk, etc. However, if the write clock at the outermost periphery is set in accordance with those factors, there is a problem that the recording speed on the inner peripheral side is reduced.

For example, when the upper limit of the recording speed is limited by the double linear velocity due to factors such as the signal processing system, the minimum strategy pulse, and the media sensitivity of the optical disk, the linear velocity at the time of recording the outermost periphery is doubled. Must be set to Therefore, the CAV control of the spindle motor must be set so that the linear velocity at the outermost periphery becomes twice as fast.

However, in the case of a CD-R or DVD-RAM, the linear velocity at the innermost circumference is about 1 / 2.5 that of the outermost circumference. Becomes 1
There has been a problem that the recording speed is greatly reduced because the speed is lower than the double speed.

Conventionally, in reproducing data from an optical disk, the spindle motor is controlled by the CAV on the inner periphery of the optical disk and the spindle motor is controlled by the CLV on the outer periphery to read data, thereby reducing the access speed and the rotation speed during reproduction. (For example, refer to Japanese Patent Application Laid-Open No. 10-27421) has been proposed.

[0014]

However, in the above-described information reproducing apparatus, CAV and CLV are switched only when data is reproduced from the optical disk. Therefore, when data is recorded, the recording speed is reduced due to the above-described causes. There was a problem. The present invention has been made to solve the above-described problem, and has as its object to improve the recording speed at the time of data recording.

Also, as in the information reproducing apparatus described above, when data is recorded, the CAV and CLV are simply switched between the inner circumference and the outer circumference of the optical disk.
There is a problem that the rotation speed of the spindle motor becomes unstable when the LV is switched.

As in the above-described conventional information reproducing apparatus, if data is reproduced only from the optical disk (at the time of reading), even when the rotation speed of the spindle motor becomes unstable and data reading fails, It is sufficient to read the data again. However, if the rotation speed of the spindle motor becomes unstable during data recording, there is a problem that data during recording is lost.

For example, in the case of an optical disk such as a CD-R which can be recorded only once, if data recording fails, the recording destination area becomes unusable and wasted. In addition, even on an optical disk such as a CD-R / W in which data can be rewritten, already recorded data may be erased.

Therefore, the present invention provides a method of recording data at the time of CAV.
It is another object of the present invention to prevent the rotation speed of the spindle motor from becoming unstable even if the control and the CLV control are switched from one another.

[0019]

According to the present invention, there is provided an information recording / reproducing apparatus for recording / reproducing information on / from an information recording medium, comprising: a rotating means for rotating the information recording medium; Constant angular velocity control information generating means for generating constant angular velocity control information for rotating the information recording medium at a constant angular velocity; and generating constant linear velocity control information for rotating the information recording medium at a constant linear velocity. Linear velocity constant control information generating means, linear velocity information output means for detecting a linear velocity when the information recording medium is rotating, and outputting the linear velocity information (linear velocity detection data); Switching linear velocity information for storing predetermined switching linear velocity information at a position on a recording area where switching is performed from a constant angular velocity to a constant linear velocity or from a constant linear velocity to a constant angular velocity. Storage means, and, upon recording on the information recording medium, the angular velocity based on the linear velocity information output by the linear velocity information output means and the switching linear velocity information stored in the switching linear velocity information storage means. Switching control information generating means for generating switching control information for controlling switching between the constant control information and the linear velocity constant control information; and the angular velocity constant control information generating means based on the switching control information generated by the means. Control information selecting means for selecting and outputting any one of the constant angular velocity control information and the constant linear velocity control information generated by the constant linear velocity control information generating means, and the constant angular velocity control selected by the means. A time for controlling the rotation speed of the information recording medium by the rotating means so that the information or the linear velocity constant control information has a constant period. It is provided with a speed control means.

Further, in order to achieve the above-mentioned object, in the above-mentioned information recording / reproducing apparatus, the switching control information generating means may include a linear velocity information output from the linear velocity information output means and Means for comparing the linear velocity information at the time of switching stored in the linear velocity information storage means, and generating control information when the linear velocity information becomes larger than the linear velocity information at the time of switching; It is preferable to include means for generating switching control information for controlling switching between the constant angular velocity control information and the constant linear velocity control information based on the generated control information.

In the information recording / reproducing apparatus as described above, the switching control information generating means may generate the control information when the linear velocity information is smaller than the switching linear velocity information by a predetermined amount. It is preferable to provide a stopping means.

In the information recording / reproducing apparatus as described above, in the vicinity of a position on a recording area where the rotation of the information recording medium is switched from a constant angular velocity to a constant linear velocity or from a constant linear velocity to a constant angular velocity. Preferably, there is provided means for making the constant linear velocity control information generated by the constant linear velocity control information generating means substantially coincide with the cycle and phase of the constant angular velocity control information generated by the constant angular velocity control information generating means.

Further, in the information recording / reproducing apparatus as described above, the constant linear velocity control information generating means counts a clock based on rotation speed information detected when the rotating means rotates the information recording medium. Counting means for outputting the count information, and comparing the count information output by the means with the linear velocity information output by the linear velocity information output means, and when the linear velocity information becomes equal, Means for outputting count information; means for selecting and outputting one of the count information and the edge information of the angular velocity constant control information based on the switching control information; and decoding the count information to constant linear velocity. It is preferable to include a means for outputting as control information.

Further, in the information recording / reproducing apparatus as described above, the angular velocity constant control information generating means is provided with the angular velocity information based on rotation speed information detected when the information recording medium is rotated by the rotating means. Means for generating constant control information may be provided.

In the information recording / reproducing apparatus as described above, the constant linear velocity control information generating means includes means for generating the constant linear velocity control information based on the wobble information detected from the information recording medium. Good.

Alternatively, in the information recording / reproducing apparatus as described above, the constant linear velocity control information generating means is provided with means for generating the constant linear velocity control information based on the reproduction information detected from the information recording medium. Good.

A rotating means for rotating the information recording medium; a constant angular velocity control information generating means for generating constant angular velocity control information for rotating the information recording medium at a constant angular velocity; A constant linear velocity control information generating means for generating constant linear velocity control information for rotating at a linear velocity, detecting a linear velocity when the information recording medium is rotating, and converting the linear velocity information (linear velocity detection data) Linear velocity information output means for outputting, and a predetermined switching linear velocity at a position on a recording area for switching the rotation of the information recording medium from a constant angular velocity to a constant linear velocity or from a constant linear velocity to a constant angular velocity Switching linear velocity information storage means for storing information; linear velocity information output by the linear velocity information output means during recording on the information recording medium; and switching linear velocity information storage means Switching control information generating means for generating switching control information for controlling switching between the constant angular velocity control information and the constant linear velocity control information based on the stored switching linear velocity information; and switching control generated by the means. Control information for selecting and outputting one of constant angular velocity control information generated by the constant angular velocity control information generating means and constant linear velocity control information generated by the constant linear velocity control information generating means based on the information Selection means, and rotation speed control means for controlling the rotation speed of the information recording medium by the rotation means such that the constant angular velocity control information or the constant linear velocity control information selected by the means has a constant period. An apparatus for controlling a rotation speed of an information recording medium is also provided.

Further, in the rotation speed control device for an information recording medium as described above, the switching control information generating means includes:
The linear velocity information output by the linear velocity information output means is compared with the switching linear velocity information stored in the switching linear velocity information storage means, and the linear velocity information is compared with the switching linear velocity information. Means for generating control information when is increased, and means for generating switching control information for controlling switching between the constant angular velocity control information and the constant linear velocity control information based on the control information generated by the means. It is good to consist of.

In the above-described information recording medium rotational speed control apparatus, the switching control information generating means may include a step of controlling the control when the linear velocity information becomes smaller than the switching linear velocity information by a predetermined amount. Means for stopping the generation of information may be provided.

Further, in the information recording medium rotation speed control device as described above, the rotation of the information recording medium is switched from a constant angular velocity to a constant linear velocity or from a constant linear velocity to a constant angular velocity. In the vicinity of the position, there is provided means for causing the constant linear velocity control information generated by the constant linear velocity control information generating means to substantially coincide with the cycle and phase of the constant angular velocity control information generated by the constant angular velocity control information generating means. Good.

In the above-described information recording medium rotational speed control apparatus, the constant linear velocity control information generating means may output the rotational speed information detected when the information recording medium is rotated by the rotating means. Counting means for counting a clock based on the clock and outputting the count information;
Means for comparing the count information output by the means with the linear velocity information output by the linear velocity information output means and outputting the count information when the linear velocity information becomes equal to the linear velocity information; Means for selecting and outputting one of the edge information of the count information and the angular velocity constant control information based on the above, and means for decoding the count information and outputting it as linear velocity constant control information. Good.

Further, in the rotation speed control device for an information recording medium as described above, the constant angular velocity control information generating means is provided with information on the number of rotations detected when the information recording medium is rotated by the rotation means. Means for generating the angular velocity constant control information may be provided.

In the above-mentioned apparatus for controlling the rotational speed of an information recording medium, the constant linear velocity control information generating means generates the constant linear velocity control information based on the wobble information detected from the information recording medium. It is preferable to provide a means for performing this.

In the above-described apparatus for controlling the rotation speed of an information recording medium, the constant linear velocity control information generating means may generate the constant linear velocity control information based on the reproduction information detected from the information recording medium. It is preferable to provide a means for performing this.

[0035]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 2 is a block diagram showing the configuration of the optical disk drive according to one embodiment of the present invention.

This optical disk drive uses a CD-R, C
An information recording / reproducing apparatus for recording and reproducing information on / from an information recording medium such as a DR / W / DVD-RAM;
A main part related to the rotation of the information recording medium corresponds to a rotation speed control device (each part described later).

This optical disk drive comprises a spindle motor 2 for rotating and driving an optical disk 1 as an information recording medium.
And an optical pickup 3 for reading recorded information on the optical disk 1 using a laser beam and writing information on the optical disk 1.

Further, a WBL signal detecting circuit 6 for detecting a wobble signal (wobble information) from the recording information read by the optical pickup 3, and a wobble signal detected by the WBL signal detecting circuit 6 are compared with a phase comparator, a low-pass filter, A write clock generating circuit 7 is provided which generates a write clock (detection clock) by multiplying the frequency by a frequency feedback circuit (PLL) including an error amplifier and a voltage controlled oscillator.

Further, a servo signal detecting circuit 8 for detecting a servo signal from the recorded information read by the optical pickup 3, and a focusing and focusing of the optical pickup 3 based on the servo signal detected by the servo signal detecting circuit 8.
A servo unit 9 for controlling tracking is provided.

A linear velocity detecting circuit 11 for detecting the linear velocity of the optical disk 1 based on the detection clock and the FG signal.
Control for controlling the spindle motor 2 based on the FG signal output from the spindle driver (SP driver) 13, the detection clock output from the selector (not shown), and the linear velocity detection data output from the linear velocity detection circuit 11. A spindle motor control unit 12 that outputs a signal to a spindle driver 13 is provided.

Further, a spindle driver 13 for driving the spindle motor 2 and outputting an FG signal proportional to the rotation frequency of the spindle motor 2 is provided. This spindle driver 13 is based on rotation number information (FG signal) detected when the information recording medium (optical disk 1) is rotated by the rotating means (spindle motor 2, spindle motor control unit 12, spindle driver 13). It functions as a means for generating the angular velocity constant control information (CAV reference signal).

Next, the principle of detecting linear velocity detection data in the linear velocity detecting circuit 11 will be described. Wobble is recorded on the optical disc 1 at a constant linear velocity (CLV), read by the optical pickup 3, and the frequency of the wobble signal output from the optical pickup 3 is a frequency proportional to the linear velocity of reading.

Accordingly, the write clock generated by multiplying the wobble signal also has a frequency proportional to the linear velocity for reading. The linear velocity can be measured. Also,
For an optical disk on which data is recorded by CLV, the linear velocity can be measured in the same manner as described above by using an RF signal.

Next, the spindle motor control section 12 will be described. FIG. 1 is a functional block diagram showing components of the spindle motor control unit 12.

The spindle motor control section 12 controls the spindle motor 2 at a constant rotation speed (constant angular speed: CAV) and sets linear velocity setting data (linear velocity information at the time of switching) at an area boundary for controlling the spindle motor 2 with CLV. The register 21 for the linear velocity setting data for storing the data. The linear velocity setting data is written into the linear velocity setting data register 21 by a control unit (not shown).

Further, an edge detection circuit 22 which detects an edge of the FG signal by a detection clock and outputs it as an FG edge detection signal, a linear velocity setting data, an FG edge detection signal, and a CAV / CLV switching control signal generation circuit 2 described later
4 is provided with a CLV reference signal generation circuit 23 which inputs a CAV / CLV switching control signal output by the control signal 4 and a detection clock and outputs a CLV reference signal (constant linear velocity control reference signal).

Further, a FG edge detection signal, a linear velocity setting data, a linear velocity detection data, a detection clock, and a mode reset signal are inputted to generate and output a CAV / CLV switching control signal for switching between CAV control and CLV control. A CAV / CLV switching control signal generation circuit 24 is provided.

Further, at the time of CAV control by the CAV / CLV switching control signal, the FG signal (CAV reference signal,
Angular velocity constant control reference signal), and CLV
And a selector 25 for selecting and outputting a reference signal for rotation and a spindle rotation speed control signal for controlling the rotation of the spindle motor 2.
A spindle rotation speed control circuit 26 for controlling the spindle motor 2 so that the period of the G signal is constant is provided.

That is, the spindle motor 2, the spindle motor control unit 12 and the spindle driver 13
Functions as a rotating means for rotating the information recording medium (optical disc 1).

Also, the spindle driver 13 controls angular velocity constant control information (constant angular velocity control reference signal) for rotating the information recording medium at a constant angular velocity (CAV).
The function of the constant angular velocity control information generating means for generating the CAV reference signal) is provided by the CLV reference signal generating circuit 23, which controls the linear velocity constant control information (CLV) for rotating the information recording medium at a constant linear velocity (CLV). Linear velocity constant control reference signal:
The function of the constant linear velocity control information generating means for generating the CLV reference signal is performed.

Further, the linear velocity detecting circuit 11 detects the linear velocity at the time of rotation of the information recording medium and outputs the linear velocity information (linear velocity detection data). The linear velocity setting data register 21 stores a predetermined linear velocity at a position on a recording area where the rotation of the information recording medium is switched from a constant angular velocity to a constant linear velocity or from a constant linear velocity to a constant angular velocity. The switching linear velocity information storage means for storing information (boundary area linear velocity data) functions.

The CAV / CLV switching control signal generation circuit 24 stores the linear velocity information output by the linear velocity information output means and the switching linear velocity information storage means during recording on the information recording medium. Switching control information (CAV / CV / CV) for controlling switching between the angular velocity constant control information and the linear velocity constant control information based on the switched linear velocity information.
A function of a switching control information generating means for generating a CLV switching control signal).

Further, the selector 25 includes a constant angular velocity control information generated by the constant angular velocity control information generating means based on the switching control information generated by the switching control information generating means, and a constant linear velocity control information generating means. It functions as control information selecting means for selecting and outputting one of the constant linear velocity control information generated by the means.

Further, the spindle rotational speed control circuit 26 controls the information recording by the rotating means so that the constant angular velocity control information or the constant linear velocity control information selected by the control information selecting means has a constant period. It functions as a rotation speed control means for controlling the rotation speed of the medium.

The CLV reference signal generation circuit 23
The linear velocity constant control information (CLV reference signal) is generated based on the wobble information (wobble signal) detected from the information recording medium, and based on the reproduction information (RF signal) detected from the information recording medium. It also functions as means for generating the linear velocity constant control information (CLV reference signal).

Next, the rotation speed control processing of the optical disc 1 according to the present invention in the spindle motor control section 12 shown in FIG. 1 will be described. First, linear velocity setting data (boundary area linear velocity data) at a radial position on the optical disc 1 where switching between CAV and CLV is to be performed is previously set in the linear velocity setting data register 21 (the setting is not shown). Is performed by the control unit).

At the time of rotation of the optical disk 1 for recording and reproducing information, the CAV / CLV switching control signal generation circuit 24
CAV / CL based on the set value of the linear velocity setting data
A V switching control signal is generated. The detailed function of the CAV / CLV switching control signal generation circuit 24 will be described later.

The selector 25 outputs a constant linear velocity control reference signal (CLV reference signal) generated by the CLV reference signal generation circuit 23 as a reference signal to be output to the spindle rotation speed control circuit 26 based on the CAV / CLV switching control signal. ) And an angular velocity constant control reference signal (FG signal).

That is, the selector 25 switches the control method of the spindle motor from the CAV control to the CLV control. Actually, when the CAV / CLV switching control signal is at the low level “L” (in the case of CAV), the FG signal is output to the spindle rotation speed control circuit 26.

When the CAV / CLV switching control signal is at the high level “H” (in the case of CLV), the spindle rotation speed control circuit 26 is supplied to the CLV reference signal generating circuit 23 for the CLV. Output the reference signal.
Although the details of the function of the CLV reference signal generation circuit 23 will be described later, the cycle of the CLV reference signal is set to m times (m: integer) the cycle of the detection clock.

The CLV reference signal generation circuit 23
At the time of data recording, a CLV reference signal for rotating the optical disc 1 at a constant linear velocity is generated based on the wobble signal detected from the optical disc 1, and at the time of data reproduction,
Based on the RF signal detected from the optical disc 1, a CLV reference signal for rotating the optical disc 1 at a constant linear velocity is generated.

Then, the spindle rotation speed control circuit 26
Then, a spindle rotation speed control signal for controlling the rotation of the spindle motor 2 is output so that the cycle of the input CLV reference signal or FG signal is constant, and the rotation speed of the spindle motor 2 is controlled.

Thus, the spindle rotation speed control circuit 2
6 controls the spindle motor 2 so that the FG signal has a constant period when the FG signal is input. As a result, the spindle motor 2 rotates at CAV. Also, the spindle rotation speed control circuit 26
When the LV reference signal is input, the spindle motor 2 is controlled so that the CLV reference signal becomes constant.
As a result, the spindle motor 2 rotates at CLV.

Next, the detailed function of the CAV / CLV switching control signal generation circuit 24 will be described. FIG.
FIG. 3 is a functional block diagram showing an internal configuration of an AV / CLV switching control signal generation circuit 24. The CAV / CLV switching control signal generation circuit 24 includes a comparator 31 and a synchronous set / reset flip-flop 32.

The comparator (CMP) 31 inputs linear velocity detection data and linear velocity setting data, and outputs an output signal based on a comparison result between the two data to the synchronous set / reset flip-flop 32. When the linear velocity detection data becomes larger than the set data, a high level signal “H” is output to the synchronous set / reset flip-flop 32.

Synchronous set-reset flip-flop 3
Reference numeral 2 denotes an FG edge detection signal at a clock enable (CLKEN) terminal, an output signal from the comparator 31 at a set (Set) terminal, a mode reset signal at a reset (Reset) terminal, and a detection clock at a clock (CK) terminal. Input each, CAV based on each signal
/ CLV switching control signal is output.

That is, the comparator 31 stores the linear velocity information (linear velocity detection data) output by the linear velocity information output means (linear velocity detection circuit 11) and the switching linear velocity information storage means (linear velocity setting data). Register 2
The switching linear velocity information (boundary area linear velocity data) stored in 1) is compared, and when the linear velocity information becomes larger than the switching linear velocity information, the control information (high-level output signal) ) Serves as a means for generating

The synchronous set / reset flip-flop 32 is provided with the constant angular velocity control information (FG signal: corresponding to the CAV reference signal) based on the control information (high-level output signal) generated by the means. Switching control information (CAV / CLV switching control signal) for controlling switching of the linear velocity constant control information (CLV reference signal)
Serves as a means for generating

Next, control processing of the CAV / CLV switching control signal generation circuit 24 shown in FIG. 3 will be described. The comparator 31 outputs a high level signal when the linear velocity detection data detected from the spindle motor 2 becomes larger than the preset linear velocity setting data (boundary area linear velocity data).

At this time, since a high-level signal is input to the set terminal of the synchronous set / reset flip-flop 32, the synchronous set / reset flip-flop 32 outputs a high-level CAV / CLV switching control signal, and its output is The high level is maintained until a mode reset signal is input to the reset terminal.

The advantages of arranging the synchronous set / reset flip-flop 32 are as follows. Since it is expected that the linear velocity detection data has a detection error, there is a possibility that the output signal of the comparator 31 becomes high level at the switching point and then becomes low level again.

Therefore, when the output signal of the comparator 31 is a CAV / CLV switching control signal without arranging the synchronous set / reset flip-flop 32, the linear velocity detection data is detected near the CAV / CLV switching position on the optical disk 1. The low level and the high level may appear alternately due to an error.

As a result, the spindle rotation speed control circuit 2
The reference signal input to 6 is also switched alternately, and the rotation control of the spindle motor 2 may become unstable. In order to avoid this, the synchronous set / reset flip-flop 32 is provided.

As a method for preventing the switching of the CAV / CLV switching control signal due to the detection error of the linear velocity detection data, the present invention can be realized by disposing a comparator having hysteresis instead of the comparator 31. Can be.

More specifically, the comparator with hysteresis switches to a high level "H" when the linear velocity detection data becomes larger than the linear velocity setting data when the output signal is at a low level "L", and outputs the output signal. Is high level "H", the output signal of low level "L" is output when the linear velocity detection data becomes (linear velocity setting data-α). This “α” value is set to a value larger than the detection error of the linear velocity data.

That is, in this case, the means for stopping the generation of the control information (high-level signal) when the hysteresis of the comparator becomes smaller than the switching linear velocity information by a predetermined amount. Perform the function of

Next, the CLV reference signal generating circuit 23
A detailed function will be described. FIG. 4 is a functional block diagram showing the internal configuration of the CLV reference signal generation circuit 23. The CLV reference signal generation circuit 23 includes a selector 4
1, counter 42, comparator 43 and decoder 44
Consists of

The selector 41 outputs an FG edge detection signal during CAV control according to the CAV / CLV switching control signal.
During the CLV control, an output signal of a comparator 43 described later is selected and output. The counter 42 clears the synchronization (S
An output signal from the selector 41 is input to a CLR (CLR) terminal, a detection clock is input to a clock (CK) terminal, and a count signal (count information: count value) is output from a Q terminal.

The comparator 43 has a counter 4 connected to the A terminal.
2, the linear velocity setting data is input to the B terminal, and the count signal input to the A terminal is
The output signal is set to a high level "H" when it becomes equal to the linear velocity setting data input to the terminal. The decoder 44
The count signal from the counter 42 is input, decoded, and output as a CLV reference signal.

That is, the counter 42 is controlled by the rotating means (spindle motor 2, spindle motor control unit 1).
2. The function of a counting means for counting a clock based on rotation speed information (FG edge detection signal) detected when the information recording medium is rotated by the spindle driver 13), and outputting the count information.

The comparator 43 outputs the count information (count value) output by the counting means and the linear velocity information output means (linear velocity detecting circuit 11).
The linear velocity information (linear velocity detection data) output from the above is compared with the linear velocity information, and when the linear velocity information becomes equal to the linear velocity information, the function of outputting the count information is performed.

Further, the selector 41 selects one of the count information and the edge information (FG edge detection signal) of the angular velocity constant control information based on the switching control information (CAV / CLV switching control signal). Function as a means for outputting. Furthermore, the decoder 4
4 functions as means for decoding the count information and outputting it as constant linear velocity control information (CLV reference signal).

Further, when the decoder 44 switches the rotation of the information recording medium from a constant angular velocity to a constant linear velocity, or from a constant linear velocity to a constant angular velocity, in the vicinity of a recording area, the linear velocity is kept constant. Control information generation means (CL
The constant linear velocity control information (CLV reference signal) generated by the V reference signal generation circuit 23) is used as the constant angular velocity control information (FG signal) generated by the constant angular velocity control information generation means (spindle driver 13). It functions as a means for making the period and the phase substantially coincide with each other.

Next, control processing of the CLV reference signal generation circuit 23 shown in FIG. 4 will be described. Selector 41
Inputs the FG edge detection signal and the signal output from the comparator 43. When the CAV / CLV switching control signal is at a low level “L” (during CAV control), the FG edge detection signal is changed to a high level “H”. In the case of (CLV control), when the output of the counter 42 becomes equal to the linear velocity setting data, a signal which becomes high level "H" is output.

The counter 42 clears when the signal input from the selector 41 to the synchronous clear (SCLR) terminal is at the high level “H”, outputs the signal input from the selector 41 to the decoder 44, Decodes the signal and outputs it as a CLV reference signal.

FIG. 5 shows the CAV / CLV switching control signal and F
FIG. 4 is a timing chart showing changes in a G edge detection signal and an output signal of the counter 42;

FIG. 11A shows the timing when the FG edge detection signal is input to the synchronous clear terminal of the counter 42 (when the CAV / CLV switching control signal is at a low level).

In this case, the counter 42 clears the signal by the high-level FG edge detection signal and then sets the next FG.
The counting operation is performed until the edge detection signal is input, and counting is performed up to m (m: a positive integer). Therefore, since the spindle motor 2 is controlled by the CAV, the period of the FG signal becomes constant.

Further, since the frequency of the detection pulse increases as the radial position of reading on the optical disk 1 moves toward the outer periphery, the number counted from the FG edge detection signal to the next FG edge detection signal increases.

FIG. 9B shows the timing when the output signal of the comparator 43 is input to the synchronous clear terminal of the counter 42 (when the CAV / CLV switching control signal is at a high level).

Since the spindle motor 2 is under CAV control immediately before the CAV / CLV switching control signal goes high, the FG signal immediately after the CAV / CLV switching control signal goes low. Remains constant.

However, after switching from the CAV control to the CLV control, when the output signal of the counter 42 becomes equal to the linear velocity setting data (here, n) by the comparison of the comparator 43, the counter 42 must be synchronously cleared. become.

Accordingly, the cycle of clearing the counter 42 (= the cycle of the CLV reference signal) is (the cycle of the detection clock × n), and the cycle (the cycle of the detection clock × n).
Is input to the spindle rotation speed control circuit 26, the spindle rotation speed control circuit 26 can control the spindle motor 2 so that (the period of the detection clock × n) becomes constant.

The above detection clock is recorded on the optical disc 1 by
Controlling the spindle motor 2 so that the detection clock cycle is constant means that the spindle motor 2 is controlled so that the cycle of the wobble signal is constant, since it is synchronized with the wobble recorded in the LV. As a result, the spindle motor 2 is controlled by the CLV.

The decoder 44 generates and outputs a CLV reference signal from the output signal of the counter 42 based on the following equation, for example. Here, clvref: CLV reference signal, cnt. q: output signal value of the counter 42.

[0096]

Equation 1 clvref = (cnt.q <n / 2)

The decoder 44 can generate a CLV reference signal having a duty ratio of 50% and a period and a phase of the FG signal almost equal at the time of switching by performing decoding based on the logical expression represented by the equation (1). it can.

When the FG edge detection signal lags behind the FG signal by several clocks (delay at the time of edge detection or delay at the time of glitch removal), it can be absorbed here.

For example, when the FG edge detection clock is detected five clocks later than the FG signal, a reference signal for CLV is generated and output from the output signal of the counter 42 based on the following equation.

[0100]

## EQU2 ## clvref = (cnt.q <n / 2-5) +
(Cnt.q> n-5)

The decoder 44 performs decoding based on the logical expression expressed by the equation 2 so that the duty ratio becomes 50 when switching from CAV control to CLV control.
% When the switching and the phase of the FG signal are almost the same when switching.
A reference signal for V can be generated.

Therefore, since the cycle and phase of the reference signal at the time of switching from CAV control to CLV control are substantially the same, it is possible to perform control without disturbing the rotation of the spindle motor 2 when switching between CAV control and CLV control. it can.

As described above, this optical disk drive uses the spindle motor CA
V control, and CLV control is performed on the outer circumference side. Therefore, even if the upper limit of the recording / reproducing speed is limited by the double speed linear velocity, for example, CAV control is performed such that the innermost circumference becomes 1 × speed when writing on the inner circumference side. High-speed writing is possible without lowering the recording speed of the inner circumference than at the same-time writing, since recording can be performed by performing CLV control from the radial position where the linear velocity doubles. become.

Further, since the difference between the rotation speed of the spindle motor 2 at the time of the innermost access and the rotation speed at the time of the outermost access is smaller than when the spindle motor is CLV controlled on the entire surface of the optical disc 1, a low torque Even if an inexpensive spindle motor 2 that can only be generated is used, the rotational speed does not become unstable, and the manufacturing cost of the optical disk drive can be suppressed.

Further, the CAV / CLV switching control signal generation circuit 24 for generating the CAV / CLV switching control signal compares the linear velocity setting data read from the linear velocity setting data register 21 with the detected linear velocity detection data. And the synchronous set / reset flip-flop 32 as described above.
The switching of the AV / CLV switching control signal does not occur alternately. Therefore, even when switching from the CAV control to the CLV control, the rotation of the spindle motor 2 can be controlled stably.

If the comparator 31 is a comparator that compares the linear velocity setting data read from the linear velocity setting data register 21 with the detected linear velocity detection data with hysteresis, the comparator 31 is switched by a linear velocity detection error. The CAV / CLV switching control signal does not alternately switch near the position.
In switching of the LV control, control for further stabilizing the rotation of the spindle motor 2 can be performed.

Further, in the vicinity of the switching position of the CAV control and the CLV control, the CLV reference signal is made to substantially coincide with the cycle and phase of the FG edge detection signal (CAV reference signal). The rotation speed of the spindle motor 2 can be stabilized.

The CLV reference signal generating circuit 23
Is the FG signal detected from the optical disc 1 (CLV reference)
, A comparator 43 for comparing the output signal of the counter 42 with preset linear velocity setting data, and comparing the edge detection signal of the FG signal and the output signal of the counter 42 with the linear velocity setting data. One of the output signals of the comparator 43
Counter 42 selected by V / CLV switching control signal
, And a decoder 44 for decoding the output signal of the counter 42 and outputting the decoded signal as a CLV reference signal.
CL output near the switching position between CAV control and CLV control
The phase of the V reference signal can be made substantially coincident with the cycle of the CAV reference signal, and the rotation speed of the spindle motor 2 can be stabilized even when the reference signal is switched.

Further, since the CAV reference signal for rotating the optical disc 1 at a constant angular velocity is generated based on the FG signal output from the spindle driver 13,
It is not necessary to newly provide a means for detecting the FG signal, and the manufacturing cost of the device can be reduced.

Further, since the CLV reference signal for rotating the optical disc 1 at a constant linear velocity is generated based on the wobble signal detected from the optical disc 1, it is easy to control the spindle when recording data. Can be applied.

Furthermore, the RF detected from the optical disc 1
If a CLV reference signal for rotating the optical disc 1 at a constant linear velocity is generated based on the signal, it can be easily applied at the time of spindle control when reading data.

[0112]

As described above, according to the information recording / reproducing apparatus and the information recording medium rotational speed control apparatus of the present invention, the recording speed during data recording can be improved. Further, even if the CAV control and the CLV control are switched from one another during data recording, the rotation speed of the spindle motor can be prevented from becoming unstable.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing components of a spindle motor control unit 12 shown in FIG.

FIG. 2 is a block diagram showing a configuration of an optical disk drive according to an embodiment of the present invention.

FIG. 3 is a functional block diagram showing an internal configuration of a CAV / CLV switching control signal generation circuit 24 shown in FIG.

FIG. 4 is a functional block diagram showing an internal configuration of the CLV reference signal generation circuit 23 shown in FIG.

5 is a timing chart showing changes in a CAV / CLV switching control signal, an FG edge detection signal, and an output signal of the counter 42 in the reference signal generation circuit for CLV shown in FIG. 4;

[Explanation of symbols]

 1: optical disk 2: spindle motor 3: optical pickup 6: WBL signal detection circuit 7: write clock generation circuit 8: servo signal detection circuit 9: servo section 11: linear velocity detection circuit 12: spindle motor control section 13: spindle driver 21 : Linear speed setting data register 22: Edge detection circuit 23: CLV reference signal generation circuit 24: CAV / CLV switching control signal generation circuit 25, 41: Selector 26: Spindle rotation speed control circuit 31, 43: Comparator 32: Synchronization Formula set reset flip-flop 42: Counter 44: Decoder

Claims (16)

[Claims] 1. An information recording / reproducing apparatus for recording / reproducing information on / from an information recording medium, comprising: rotating means for rotating the information recording medium; and constant angular velocity control information for rotating the information recording medium at a constant angular velocity. Constant angular velocity control information generating means for generating a constant linear velocity control information generating means for generating constant linear velocity control information for rotating the information recording medium at a constant linear velocity; and Linear velocity information output means for detecting a linear velocity and outputting the linear velocity information (linear velocity detection data); and rotating the information recording medium from a constant angular velocity to a constant linear velocity or from a constant linear velocity to a constant. A switching linear velocity information storage means for storing predetermined switching linear velocity information at a position on a recording area for switching to the angular velocity, the linear velocity information during recording on the information recording medium. Switching for controlling switching between the constant angular velocity control information and the constant linear velocity control information based on the linear velocity information output by the report output means and the switching linear velocity information stored in the switching linear velocity information storage means. Switching control information generating means for generating control information; constant angular velocity control information generated by the constant angular velocity control information generating means based on the switching control information generated by the means; and constant linear velocity control information generating means. Control information selecting means for selecting and outputting one of the generated linear velocity constant control information; and controlling the angular velocity constant control information or the linear velocity constant control information selected by the means to have a constant period. An information recording / reproducing apparatus, comprising: a rotation speed control unit for controlling a rotation speed of the information recording medium by a rotation unit. 2. The information recording / reproducing apparatus according to claim 1, wherein the switching control information generation unit stores the linear velocity information output by the linear velocity information output unit and the switching linear velocity information storage unit. Means for generating control information when the linear velocity information is greater than the switching linear velocity information, based on the control information generated by the means. An information recording / reproducing apparatus, comprising: means for generating switching control information for controlling switching between constant angular velocity control information and said constant linear velocity control information. 3. The information recording / reproducing apparatus according to claim 2, wherein the switching control information generating means generates the control information when the linear velocity information becomes smaller than the switching linear velocity information by a predetermined amount. An information recording / reproducing apparatus characterized by comprising means for stopping the operation. 4. The information recording and reproducing apparatus according to claim 1, wherein the rotation of the information recording medium is changed from a constant angular velocity to a constant linear velocity, or from a constant linear velocity to a constant angular velocity. In the vicinity of the position on the recording area where the switching is performed, the constant linear velocity control information generated by the constant linear velocity control information generating means is substantially equal to the period and phase of the constant angular velocity control information generated by the constant angular velocity control information generating means. An information recording / reproducing apparatus, comprising: means for matching. 5. The information recording / reproducing apparatus according to claim 1, wherein the constant linear velocity control information generating means is detected when the information recording medium is rotated by the rotating means. Counting means for counting clocks based on the rotation speed information, and counting means for outputting the count information; comparing the count information output by the means with the linear velocity information output by the linear velocity information output means;
Means for outputting the count information when it becomes equal to the linear velocity information; and means for selecting and outputting one of the count information and the edge information of the angular velocity constant control information based on the switching control information. Means for decoding said count information and outputting it as constant linear velocity control information. 6. The information recording / reproducing apparatus according to claim 1, wherein the constant angular velocity control information generating means detects when the information recording medium is rotated by the rotating means. An information recording / reproducing apparatus, comprising: means for generating the angular velocity constant control information based on rotation speed information. 7. The information recording / reproducing apparatus according to claim 1, wherein the linear velocity constant control information generating means is configured to generate the linear velocity based on wobble information detected from the information recording medium. An information recording / reproducing apparatus, comprising: means for generating constant control information. 8. The information recording / reproducing apparatus according to claim 1, wherein said linear velocity constant control information generating means outputs said linear velocity based on reproduction information detected from said information recording medium. An information recording / reproducing apparatus, comprising: means for generating constant control information. 9. A rotating means for rotating the information recording medium, a constant angular velocity control information generating means for generating constant angular velocity control information for rotating the information recording medium at a constant angular velocity, and Constant linear velocity control information generating means for generating constant linear velocity control information for rotating at a linear velocity of: detecting a linear velocity during rotation of the information recording medium, and converting the linear velocity information (linear velocity detection data) Linear velocity information output means for outputting, and a predetermined switching linear velocity at a position on a recording area for switching the rotation of the information recording medium from a constant angular velocity to a constant linear velocity, or from a constant linear velocity to a constant angular velocity. Switching linear velocity information storage means for storing information; and when recording on the information recording medium, the linear velocity information output by the linear velocity information output means and the switching linear velocity information storage means. Switching control information generating means for generating switching control information for controlling switching between the constant angular velocity control information and the constant linear velocity control information based on the stored switching linear velocity information; and the switching control generated by the means. Control information for selecting and outputting one of constant angular velocity control information generated by the constant angular velocity control information generating means and constant linear velocity control information generated by the constant linear velocity control information generating means based on the information Selecting means; and rotating speed control means for controlling the rotating speed of the information recording medium by the rotating means such that the constant angular velocity control information or the constant linear velocity control information selected by the means has a constant period. A rotation speed control device for an information recording medium. 10. The rotation speed control device for an information recording medium according to claim 9, wherein the switching control information generation unit stores the linear velocity information output by the linear velocity information output unit and the switching linear velocity information storage unit. Means for comparing the linear velocity information at the time of switching stored in the control section, and generating control information when the linear velocity information becomes larger than the linear velocity information at the time of switching; and control information generated by the means. Means for generating switching control information for controlling switching between the constant angular velocity control information and the constant linear velocity control information based on the control information. 11. The rotation speed control device for an information recording medium according to claim 10, wherein the switching control information generating means is configured to output the linear velocity information when the linear velocity information becomes smaller than the switching linear velocity information by a predetermined amount. A rotation speed control device for an information recording medium, comprising: means for stopping generation of control information. 12. The information recording medium rotation speed control device according to claim 9, wherein the rotation of the information recording medium is changed from a constant angular velocity to a constant linear velocity or a constant linear velocity. In the vicinity of the position on the recording area where the constant angular velocity is switched from the constant angular velocity to the constant angular velocity, the linear velocity constant control information generated by the linear velocity constant control information generating means is changed to the cycle of the angular velocity constant control information generated by the angular velocity constant control information generating means. A rotation speed control device for an information recording medium, comprising: means for making the phase substantially coincide with the phase. 13. The rotation speed control device for an information recording medium according to claim 9, wherein the constant linear velocity control information generation means rotates the information recording medium by the rotation means. Counting means for counting a clock based on the rotational speed information detected at the time, and outputting the count information; and comparing the count information output by the means with the linear velocity information output by the linear velocity information output means. And
Means for outputting the count information when it becomes equal to the linear velocity information; and means for selecting and outputting one of the count information and the edge information of the angular velocity constant control information based on the switching control information. Means for decoding the count information and outputting the same as constant linear velocity control information. 14. The information recording medium rotation speed control device according to claim 9, wherein the angular velocity constant control information generation means includes a step of: rotating the information recording medium by the rotation means. A means for generating the angular velocity constant control information based on the detected rotational speed information. 15. The rotation speed control device for an information recording medium according to claim 9, wherein the constant linear velocity control information generating means is configured to output the wobble information detected from the information recording medium. A rotation speed control device for an information recording medium, further comprising means for generating the constant linear velocity control information. 16. The information recording medium rotation speed control device according to claim 9, wherein the constant linear velocity control information generating means is configured to output the constant linear velocity control information based on reproduction information detected from the information recording medium. A rotation speed control device for an information recording medium, further comprising means for generating the constant linear velocity control information.