JPH0246575A - Optical disk player - Google Patents

Abstract

PURPOSE:To reduce the heating and power consumption of a servo driver by providing a peak detector for detecting a peak value of a servo signal and a power source supplying circuit for varying a driving voltage to be supplied to the servo driver in accordance with this detection value. CONSTITUTION:The subject player possesses a compact disk 1, optical pick-up 2, signal processing circuit 4, system controller 6, AD converter 10, digital servo controller 11, servo driver 12, feed motor 13, spindle motor 14, peak detector 15 and DD converter 16. Then, a peak value of a servo signal for a focus error signal FE, tracking error signal TE and spindle control signal SP, etc., is detected by the peak detector 15, and the driving voltage to be supplied to the servo driver 12 is varied to its proper amt. according to the peak detection value by the DD converter 16 to be the power source supplying circuit. By this method, the heating and power consumption of the servo driver can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to an optical disc player having a servo control system, such as a CD player, and particularly to an optical disc player that can reduce heat generation and power consumption of a servo driver.

<Prior Art> An optical disc player, such as a CD player, includes a tracking servo unit that causes the optical pickup to follow the eccentricity of the OD, a focusing servo unit that focuses the laser beam on the signal surface of the CD, and an optical pickup that moves along with the performance. There are servo control systems such as a feed circuit that drives the feed motor and a rotation control section that rotates the spindle motor at a constant linear speed. These servo control systems have a servo driver that receives servo signals such as a tracking error signal, a focus error signal, and a spindle control signal, and drives an actuator or a motor so that each displacement amount becomes zero. The driving voltage to the servo driver is a DD converter (DC/DC converter)
It is supplied by a power supply circuit called .

<Problem to be solved by the invention> However, since a constant voltage is always supplied to the servo driver regardless of the magnitude of the servo signal, the heat generation and power consumption of the servo driver are extremely high. The problem was that it was large.

From the above, an object of the present invention is to provide an optical tisf player that can reduce heat generation and power consumption of a servo driver by supplying an appropriate drive voltage necessary for servo control based on the magnitude of a servo signal. .

<Means for Solving the Problem> FIG. 1 is a block diagram of a Ci) player showing an embodiment of the present invention.

1 is a CD (compact disc), 2 is an optical pickup, 4 is a signal processing circuit, 6 is a system controller I
Q is an AD converter, 11 is a digital servo controller, 12 is a servo driver, 13 is a feed motor (thread motor), 14 is a spindle motor, 15 is a peak detector, 16 is a DD converter, FE is a focus error signal, and TE is a tracking The error signal, SPC, is the spindle control signal.

<Function> Focus error signal FE, tracking error signal T
E. A peak detector 15 detects the peak value of a servo signal such as a spindle control signal SPC, and a DD converter 16 serving as a power supply circuit changes the drive voltage supplied to the servo driver 12 to an appropriate amount according to the detected peak value. do.

<Embodiment> FIG. 1 is a block diagram of a CD player showing an embodiment of the present invention.

In the figure, 1 is a CD (compact disc).

Reference numeral 2 denotes an optical pickup that optically reads digital information recorded on the CD1 and inputs it to the signal processing circuit 4 via the RF amplifier 3. The signal processing circuit 4 is RF
While demodulating the EFM signal input from amplifier 3,
Separate the audio data and subcode, perform error detection/correction processing on the audio data, and input it to the D/A converter 5, and input the subcode and information read from the lead-in area of the CD to the system controller 6. . The D/A converter 5 D/A converts the 16-bit audio data input from the signal processing circuit 4, and inputs the output to the audio circuit 7, which outputs audio from a speaker (not shown).

The system controller 6 stores the lead-in area information input from the signal processing circuit 4 in the memory 6a, and also analyzes the Q channel of the input subcode to determine the current song number, the elapsed time of each lap, and so on. Data indicating the total elapsed time, etc. is extracted and displayed on the display section 8 as appropriate. Furthermore, the system controller 6 performs various processes such as play and search based on information input from the operation unit 9.

10 is an AD converter that converts the focus error signal FE and tracking error signal TE output from the R, F amplifier 3 into digital values; 10' is a rotation control section;
The signal processing circuit 4 generates a spindle control signal SPC based on the frame synchronization signal FLS separated from the EFM signal, and outputs it digitally. 1] is a digital servo controller, and the digital servo controller 11
A tracking servo unit that causes the optical peak-up 2 to follow the eccentricity of the CDI, a four-force sink servo unit that focuses the light on the signal surface of the CDI, a feed servo unit that drives the feed remote (sled motor) 13, A CLV servo unit 1- that rotates the spindle motor 14 at a constant linear velocity is included. Note that the motor control signal to be sent is generated by the digital servo controller 11 based on the tracking error signal EFM.

15 is a peak detector, which outputs a focus error signal FE.
, tracking error signal TE, spindle control signal S
Detects the maximum peak value among servo signals from PC, etc.

Reference numeral 16 denotes a DD converter serving as a power supply circuit, which varies the drive voltage supplied to the servo driver 12 to an appropriate amount in accordance with the peak value detected by the peak detector 15.

FIG. 2 is a flowchart of the process of the present invention.

When servo control is performed, focus error signal FE,
Tracking error signal TE, spindle control signal SP
The maximum peak value among the servo signals such as C is detected (step 101).

The peak detection value is compared with a predetermined reference value (step 102), and if it is less than the reference value, that is, the amplitude of the error signal (servo signal) of each servo control system is equal to the normal play operation. If it is smaller, the drive voltage supplied to the servo driver 12 by the DD converter J6 is suppressed to, for example, 1/2 (step 103), thereby suppressing heat generation and power consumption from the servo driver 12.

On the other hand, if the peak value is greater than or equal to the reference value in step 102, that is, only when the amplitude of the error signal (servo signal) of each servo becomes large due to external vibration, etc.
The active voltage of the servo driver 12 is supplied at full power by the DD converter 16 (step 104).

As described above, while servo control is being performed, the peak detector 15 repeatedly detects the maximum peak value in the servo signal, and supplies the signal to the servo driver 12 according to the peak value detected by the peak detector 15. The drive voltage to be used is varied to an appropriate amount.

In addition, in the flowchart of the above process, the driving voltage value supplied by the DD converter 16 was explained in two stages, but in the three stages.
The drive voltage value may be finely varied such as in stages, four stages, and so on.

In addition, in this embodiment, as an optical disc player, C
Although a D player is shown as an example, CD-ROM players, LD
The present invention may be implemented in a CD-V player, a CD-I player, or the like.

Furthermore, in the above embodiment, the maximum peak value of the servo signal was detected and the drive voltage was varied according to this value, but the peak value was detected for each servo system and the drive voltage of the servo driver was adjusted for each system. It may be configured to vary the voltage.

<Effects of the Invention> According to the present invention, the peak detector that detects the peak value of the servo signal and the power supply circuit that varies the drive voltage supplied to the servo driver according to the detected value are provided. Appropriate drive voltage required for servo control can be supplied, and heat generation and power consumption of the servo driver can be reduced.

In addition, by suppressing one heat generation to a low level, it is easier to stabilize servo control.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a CD player showing an embodiment of the present invention. FIG. 2 is a flowchart of the process of the present invention. 1..CD (compact disk), 2..optical pickup, 4..signal processing circuit, 6..system controller, 10..AD converter, 11..digital servo controller. 12...Servo driver, 13...Feed motor (thread motor). 14...Spindle motor, 15...Peak detector, 16...DD converter, FE...Focus error signal, TE...1 to racking error signal, SPC...Spindle control signal.

Claims (1)

[Scope of Claims] An optical disc player having a servo control system that drives a servo driver according to a servo signal, comprising: a peak detector that detects a peak value of the servo signal;
An optical disc player comprising: a power supply circuit that varies a drive voltage supplied to the servo driver according to the detected value.