KR20220053328A - Optical disc device and method for driving the same - Google Patents

Abstract

The present specification relates to a method for driving an optical disk device. According to one embodiment of the present invention, the method for driving the optical disk device may comprise: a step of increasing a rotation speed of the optical disk to a target speed by applying a driving voltage to a spindle motor in a rotation speed increase section; and a step of lowering a level of the driving voltage while performing an access operation so that a light focus is focused on a desired location in the rotation speed increase section. The driving method may increase a level of the driving voltage again while not performing the access operation in the rotation speed increase section.

Description

Optical disc device and method for driving the same}

This specification relates to a method of driving an optical disk device, and more particularly, to a method for reducing a maximum current when an optical disk device is connected through a USB interface.

An optical disc device capable of playing back or recording an optical disc such as a CD (Compact Disc), DVD (Digital Versatile Disc), and BD (Blu-ray Disc) capable of recording and storing data is a desktop computer (PC) or notebook computer. It is used as a peripheral device for computers. Recently, the optical disk device is mainly released in an external form so that it can be used in various devices without being built-in to a PC or a notebook computer.

The optical disk device records data or reads data recorded on the optical disk by irradiating light emitted from a laser diode to the optical disk. In particular, a lot of power is consumed when writing or reading data at a high double speed, and a lot of current is consumed when increasing the double speed or performing a search operation.

When the optical disk device is built into a host such as a PC or a notebook computer, since the stable power supply of the host is used, power problems do not occur significantly even when the optical disk device is driven at a double speed.

However, when the external optical disk device is connected to the host through the USB interface and operates, there is a limit to power transmission through the USB interface, and thus, high speed reproduction or high speed recording is inevitably limited.

In particular, when an external optical disk device is connected to a smart device such as a smart phone or tablet operated by a low-capacity battery, the power supply is more limited than when connected to a PC or notebook computer, so the current required for the search operation or double speed change is reduced. If it becomes too large, a voltage drop or a reset phenomenon may occur.

This specification has taken this situation into account, and the purpose of this specification is to smoothly perform optical disk recording and reproducing operations even when the optical disk apparatus is connected to a host with limited power supply and operates.

Another object of the present specification is to provide a method of limiting an operating current when an optical disk device is connected to a host whose power supply is limited.

According to an embodiment of the present invention, there is provided a method of driving an optical disk apparatus, comprising: increasing the rotational speed of the optical disk to a target speed by applying a driving voltage to a spindle motor during a rotational speed increasing period; and lowering the level of the driving voltage while performing an access operation for focusing the light to a desired position during the rotation speed increase section.

An optical disk apparatus according to another embodiment includes: a rotation motor for rotating the optical disk; an optical pickup for adjusting an actuator supporting the objective lens in a focusing direction and a tracking direction so that the optical focus is focused on a desired position of the optical disk; a sled motor for moving the optical pickup in the inner and outer circumferential directions of the optical disk; and a driving circuit for driving the optical pickup, the sled motor, and the rotation motor, wherein the driving circuit is configured to focus the optical light at a desired position in a rotation speed increase section in which the rotation speed of the optical disk is increased to a target speed. It is characterized in that the level of the driving voltage applied to the spindle motor is lowered when performing the access operation.

Accordingly, it is possible to effectively solve the voltage drop and reset problems caused by the power supply limitation of the connected smart device.

1a and 1b respectively show the change in double speed and the number of rotations of the spindle motor over time when the optical disk device connected to the PC operates at 24 speed;
2a and 2b respectively show the change in double speed and the number of rotations of the spindle motor over time when the optical disk device connected to the smart device operates by limiting the double speed;
3 shows the change in current consumed by the optical disk device in each servo step;
4 shows a situation in which a voltage drop occurs due to an increase in the driving current when the servo operation is changed;
5 shows the target operating current of the optical disk device according to the present invention;
6 shows an embodiment in which the overall operating current is lowered in each servo step,
Figure 7 shows an example of preventing voltage drop by lowering the operating current in each servo step according to the embodiment of Figure 6;
8A and 8B show actual waveforms of the operating current and the power supply voltage according to the embodiment of FIGS. 3 and 6, respectively;
9 illustrates an embodiment of the configuration of an optical disk device to which the present invention is applied;
10 is a flowchart illustrating an operation of an optical disk driving method according to the present invention;
11 shows another embodiment of lowering the overall operating current.

Hereinafter, an embodiment of a method of driving an optical disk device will be described in detail with reference to the accompanying drawings.

External optical disk devices are mainly connected to a host, for example, a PC, laptop PC (or notebook PC), TV, etc. through a USB (Universal Serial Bus) interface to perform an operation requested by the host, for example, reading data stored in the optical disk or optical Performs an operation to write data to the disk.

Recently, an optical disk device connected to a portable terminal or smart device such as a smart phone or smart pad rather than a PC or TV through a USB interface, for example, a USB micro type-B or USB type-C, and operated has been released.

The external optical disk device receives power from the host through the USB interface. Hosts such as PCs, notebook PCs, and TVs have less power supply restrictions, so high-speed operation requested by the host can be performed without any problem.

However, a smart device other than a notebook PC has a small battery capacity, so it is difficult to supply a large amount of power current to a device connected as a slave. Therefore, when the optical disk device is connected to a smart device and operates, power supply is limited and thus high-speed operation is limited.

1A and 1B respectively show the change in double speed and the rotational speed (RPM) of the spindle motor over time when the optical disk device connected to the PC operates at 24x speed, and FIGS. 2A and 2B are respectively shown in the smart device. It shows the change in double speed and the rotation speed (RPM) of the spindle motor over time when the connected optical disk device operates by limiting the double speed. The double speed values in FIGS. 1 and 2 are based on the CD.

In the optical disk device, as time elapses as shown in FIGS. 1A and 1B (or FIGS. 2A and 2B) (to be precise, when the access position progresses from the inner periphery of the disk to the outer periphery of the disk), the rotation speed (RPM) of the spindle motor If set constant, the double speed corresponding to the speed at which data is written or read increases linearly.

When the optical disk device is operated by being connected to a PC, in FIGS. 1A and 1B, the RPM is constant at 4875 and the double speed increases from 10.6 to 25.4 while the write/read operation proceeds from the inner periphery to the outer periphery. That is, the optical disk device operates at about 24x speed.

However, when the optical disk device operates by being connected to a smart device, since the supply of power current is small, as in FIGS. 2A and 2B , the RPM is reduced to 2031 to keep it constant, and thus the write/read operation is not performed. While proceeding from the inner periphery to the outer periphery, the double speed increases from 4.4 to 10.6, but operates by reducing the double speed to about 10 times as compared to FIG. 1A.

That is, when operating in a smart device, the optical disk device operates by reducing the recording/reproducing speed in a manner that reduces the RPM to overcome the host's power supply limitation.

As shown in FIGS. 2A and 2B , if the overall operating speed is lowered by reducing the RPM, the limitation of power supply can be overcome, but there is a problem in that the time taken for data recording or data reproduction becomes longer due to the lower operating speed.

In the present invention, in order to maximize data recording/reproduction speed while preventing voltage drop or resetting problems due to power restrictions when connecting the optical disk device to a smart device, temporarily rotating the optical disk during servo operation of the optical disk device Limits the way to reduce instantaneous power consumption by adjusting the speed.

The optical disk apparatus may perform a focusing servo, tracking servo, sled servo and spindle servo operation as a servo operation for accessing a focus to a data mark recorded on the optical disk or a track for recording the data mark.

The focusing servo and tracking servo drive an actuator supporting the objective lens in order to focus the light emitted from the laser diode (LD) on the data mark or pit in the vertical and horizontal directions with respect to the disk surface.

The focusing servo performs a focusing search operation to find a plurality of data layers in a vertical direction, a focusing-on operation to change the focus from an out-of-focus state to a focusing-on state to focus on a desired data layer, and maintains a focusing-on state including the action to

The tracking servo performs a tracking-on operation to change from a tracking-off state that does not follow a track that is a row of consecutive marks or pits in focus to a tracking-on state that follows a track in the focusing-on state, and a tracking-on operation to move from the current track to the desired track. It includes a tracking seek operation for moving a distance and an operation for maintaining a tracking-on state.

The sled servo is a sled seek operation that drives a sled motor that moves an optical pickup including a laser diode, objective lens, actuator, etc. to the inner or outer periphery of an optical disk to access a distant track. Spindle servo is an operation of driving a spindle motor to rotate an optical disk.

The focusing servo, tracking servo, sled servo, and spindle servo operate throughout the data write and read operations, but also operate when changing the optical focus from the first position to a second position away from the first position. In the access process to change the optical focus position, focusing-on operation -> tracking-on operation -> tracking seek operation, sled seek operation -> focusing-on operation -> tracking-on operation -> tracking seek operation or sled seek operation in focusing-on state -> Tracking-on operation -> Tracking seek operation can be performed in the order of operation. In this case, more current is consumed than continuous data writing/reading. Of course, the spindle servo also operates continuously for data write/read operations and optical focus shifting operations.

3 shows a change in current consumed by the optical disk device in each servo step, and FIG. 4 shows a situation in which a voltage drop occurs due to an increase in the driving current when the servo operation is changed.

When the optical disk device starts operation, the driving circuit supplies an operating voltage to the spindle motor, which in turn rotates the optical disk. When an operating voltage is supplied to the spindle motor, the optical disk starts rotating in a stationary state and the rotation speed increases until it reaches the rotation speed at a speed corresponding to the operating voltage. The current supplied to the spindle motor increases while the rotation speed of the optical disk is increased, but if the rotation speed of the optical disk is maintained at a constant speed without changing, the current supplied to the spindle motor is greatly reduced.

When power is supplied to the optical disk apparatus and the optical disk is seated on the tray, the driving circuit of the optical disk apparatus rotates the optical disk and increases the rotation speed (Spindle RPM Up) to drive an actuator to perform a focusing servo operation. A search operation and a focusing-on operation are performed to focus the light on a desired data layer. Thereafter, the driving circuit drives the actuator to perform the tracking servo operation. Tracking On is performed so that the optical focus follows the pit or mark track shaken by eccentricity while the optical disk rotates, and the track of the desired address Perform a seek operation to move to .

In the seek operation, when the target track is close, the driving circuit can move the optical focus to the target track by performing only tracking servo that drives only the actuator. In the seek operation, when the target track is far, the sled motor After the sled servo driving is performed to move the optical pickup to the vicinity of the target track, tracking servo driving the actuator is performed to move the optical focus to the target track.

In FIG. 3 , the focusing-on operation, the tracking-on operation, and the seek operation, that is, the access operation are sequentially performed step by step, but the spindle operation is performed all the time, so the current consumed for driving the optical disk device is consumed for the operation performed in each step. It is the sum of the current generated and the current consumed for spindle operation.

If current is supplied to the spindle motor while gradually increasing in order to gradually increase the rotation speed of the optical disk, the sum of the current consumed in each step and the current consumed by the spindle servo each time an access operation is performed may increase. This may not be a problem if the optical disk device is mounted and operated on the same host as the computer.

However, when the optical disk device operates using power with a limited supply amount, such as a USB interface, the capacity limit of the power supplied to the optical disk device may be exceeded at any stage of the access operation as shown in FIG. In this case, a voltage drop may occur suddenly in the supply voltage supplied by the USB interface. When a voltage drop occurs in the power supply voltage, the optical disk device may be reset to stop operation.

5 shows the target operating current of the optical disk device according to the present invention.

The driving circuit is the optical disk rotation operation by driving the spindle motor to the spindle servo, the seek operation by driving the sled motor (or stepping motor) of the sled servo, the focusing-on operation and the seek operation by driving the actuator of the focusing/tracking servo Simultaneously or sequentially, up to 1.4A of driving current may be consumed by adding the consumption current of the driving circuit board itself, which exceeds the limit for the current that the USB interface can supply.

In order for the optical disk device supplied with power through the USB interface to stably perform a disk read/write operation, the current consumed in at least one of the spindle servo, sled servo, focusing servo, and tracking servo is reduced during an access operation. For example, as shown in FIG. 5, it is necessary to keep it below 0,8A.

As a general method to reduce the operating current, the gains of the focusing servo and tracking servo can be lowered while the optical pickup is moving by driving the sled motor (or stepper motor), or You can lower the gain, or lower the recording/reproducing speed.

In the present invention, in order to lower the operating current, the gain of the spindle servo, that is, the rotation speed of the optical disk, when one or more of the focusing servo, the tracking servo, and the sled servo are sequentially performed during the optical focusing process or the optical disk access process can be adjusted.

6 shows an embodiment of lowering the overall operating current in each servo step, and FIG. 7 shows an example of reducing the operating current in each servo step according to the embodiment of FIG. 6 to prevent a voltage drop, and FIG. 8A and FIG. 8B show actual waveforms of the operating current and the power supply voltage according to the embodiments of FIGS. 3 and 6, respectively.

The driving circuit performs a disk access operation while performing an RPM-up operation of rotating the optical disk by applying an operating voltage to the spindle motor during the initial operation of the optical disk. As shown in FIG. 6 , the driving circuit controls the operating voltage applied to the spindle motor during the focusing-on operation, tracking-on operation, and seek operation constituting the disk access operation in the RPM-up period for increasing the rotation speed of the optical disk. can be lowered

The driving circuit lowers the operating voltage applied to the spindle motor to the first voltage while performing the focusing-on operation in the RPM-up period to lower the peak current supplied to the spindle motor. When the operating voltage is lowered, the optical disk rotation speed is The current rotation speed may be maintained without further increase, or the increase rate of the optical disk rotation speed may be reduced. The sum of the peak current supplied to the spindle motor and the current consumed in the focusing-on operation may be lower than the limit of the current supplied by the USB interface.

When the focusing-on operation is finished, the optical focus is focused on the desired data layer and the focusing-on state is maintained even if a vibration occurs in one rotation of the optical disk as the optical disk rotates.

After the focusing-on state, the driving circuit further increases the rotational speed of the optical disk by increasing the operating voltage applied to the spindle motor, and lowering the operating voltage of the spindle motor to the second operating voltage to maintain the increased rotational speed. A tracking-on operation is performed while holding (or increasing the rotational speed at a low rate) so that the optical focus can follow the mark/pit track.

Since the current consumed in the focusing servo-on operation is greater than the current consumed in the tracking servo-on operation, the second operating voltage supplied to the spindle motor during the tracking servo-on operation period is supplied to the spindle motor during the focusing servo-on operation period. It can be set higher than the operating voltage.

When the tracking-on operation is completed, even if the track is shaken in the inner and outer circumferential directions due to eccentricity with one rotation of the optical disk as the optical disk rotates, the optical focus can proceed in the outer circumferential direction of the disk while following one track.

After the tracking-on state, the driving circuit further increases the rotation speed of the optical disk by increasing the operating voltage applied to the spindle motor again, and lowers the operating voltage of the spindle motor to the third operating voltage to maintain the increased rotation speed. Perform a seek operation while holding (or slowing the increase in rotation speed) so that the optical focus can access the track at the desired address.

As described above, the seek operation may include a first seek operation of skipping a large number of tracks using a sled motor and a second seek operation of skipping a small number of tracks using an actuator. In many cases, the second seek operation may be performed after the first seek operation, and an operating voltage applied to the spindle motor during each seek operation may be lowered to reduce the total current consumed in the access operation.

The third operating voltage supplied to the spindle motor during the seek operation may be higher than the first operating voltage and the second operating voltage, which increases the optical disk rotation speed through the focusing-on operation and the tracking-on operation, and the seek operation This is to maintain the already increased rotational speed on the way or to further increase the rotational speed even in a state in which the rotational speed increase rate is lowered.

After accessing the optical focus to the desired track through the seek operation, the driving circuit increases the rotation speed of the optical disk by supplying an operating voltage to the spindle motor to reach the desired rotation speed, and drives when the rotation speed reaches the desired speed. By lowering the voltage to a predetermined voltage, it is possible to maintain the rotation speed of the optical disk at a speed necessary for the optical disk reproducing/recording operation.

As such, by lowering the level of the operating voltage supplied to the spindle motor when the access operation is performed during the spindle RPM-up period, the driving current may not exceed a predetermined threshold.

The driving circuit may gradually increase the operating voltage supplied to the spindle motor in proportion to the increase in the rotation speed or increase the operating voltage to a fixed value corresponding to the target speed during the period during which the access operation is not performed in the RPM-up section. may decide

In FIG. 7 , when the conventional optical disk device operates by receiving power through the USB interface, a voltage drop occurs in the power supply voltage line through which the operating current exceeds a predetermined threshold value (for example, 1.0A) during the access operation. On the other hand, the optical disk device according to the present invention operates in a current reduction mode that reduces the peak current supplied to the spindle motor during an access operation so that the operating current does not exceed the threshold voltage and the degree of voltage drop is reduced (dotted line) can be seen

In FIG. 8A showing the waveforms of the conventional optical disk device, the current supplied to the spindle motor increases during the spindle RPM-up period for increasing the rotation speed of the optical disk, but the current consumption jumps whenever an access operation is performed to a certain level If it exceeds , it can be confirmed that a voltage drop occurs in the voltage line.

However, in FIG. 8B showing the waveform of the optical disk device according to the present invention, when the access operation is performed during the spindle RPM up period, the current supplied to the spindle motor is reduced, so that a voltage drop does not occur in the voltage line, It can be seen that the optical disc reproducing/recording operation is completely performed after the access operation is terminated.

9 illustrates an embodiment of the configuration of an optical disk device to which the present invention is applied.

The optical disk apparatus 100 according to the present invention is largely an optical disk for writing data to or reading data from the optical disk 10 using a spindle motor 11 , a sled motor 12 , and a laser beam. The pickup 20, the spindle motor 11, the sled motor 12 and the optical pickup 20, and a recording/reproducing unit that processes servo signals and recording/reproducing data, and a control unit 70 that controls the recording/reproducing unit ), and an interface unit 80 that communicates with an external host to receive a data transmission command from the host and transmit data read from the optical disk to the host. The recording/reproducing unit may include an optical driving unit 30 , a digital signal processing unit 40 , an R/F unit 50 , a servo/driving unit 60 , and the like. The optical driver 30 may be included in the optical pickup 20 . It may be referred to as a driving circuit including the optical driving unit 30 and the servo/driving unit 60 .

The digital signal processing unit 40 converts the input digital data into a recording format by adding an error correction code (ECC) or the like. The light driver 30 outputs a light amount driving signal corresponding to the input signal. The optical pickup 20 records data on the optical disk 10 or reads data from the recording surface of the optical disk 10 according to the light amount driving signal.

The optical driving unit 30 outputs a recording pulse signal for forming marks on the recording surface to the laser diode of the optical pickup 20 when writing data on the disk, and when reading data from the disk, it is necessary for data reading The level value is output to the laser diode of the optical pickup 20 .

The R/F unit 50 filters the signal detected by the optical pickup 20 and outputs it as a binary signal, and also generates and outputs a tracking error signal TE, a focus error signal FE, an RF signal, and the like.

The digital signal processing unit 40 restores the binary signal to original data with its own clock phase-locked to the binary signal.

The servo/drive unit 60 generates servo signals necessary for focusing servo, tracking servo, sled servo, and spindle servo based on signals from the R/F unit 50 , and a spindle motor that rotates the optical disk 10 . (11) drives the sled motor 12 for moving the optical pickup 20 in the inner and outer circumferential directions, and also drives the current required for the focusing servo and tracking servo of the objective lens in the optical pickup 20 do.

The control unit 70 controls each element to write data to or read data from the optical disc, and controls the optical driver 30 to read the data from the optical disc 10 by controlling the optical pickup 20 In order to drive a laser diode in the internal circuit with the power for reproducing or to record data on the optical disk 10, the laser diode is driven with the power for recording.

In addition, the control unit 70 controls the servo/drive unit 60 based on the RF signal and the error signal detected from the optical pickup 20 and output from the R/F unit 50 to control the spindle motor 11 . The disk 10 is rotated at a desired speed through to perform focusing servo and tracking servo.

The interface 80 may be a USB, Serial ATA (SATA) interface, etc., and connects the host and the optical disk device 100 to exchange data or commands. In the case of an external optical disk device, power may be supplied from a host through a USB interface.

The control unit 70 controls the servo/drive unit 60 to prevent an operating voltage drop from occurring because the current consumed in the servo operation exceeds the specification of the USB interface when operating by receiving power through the USB interface. You can adjust the gain or order of the focusing servo, tracking servo, sled servo, and spindle servo.

In particular, when the controller 70 performs an access operation in an RPM-up section (or a rotation speed increase section) in which the rotation speed of the optical disk is increased to a target speed, the current consumed by adjusting the rotation speed of the optical disk is transferred to the interface Do not exceed the supply current provided by

When the focusing-on operation is performed during the RPM-up period, the controller 70 controls the servo/drive unit 60 to lower the operating voltage applied to the spindle motor to maintain the rotational speed of the optical disk without further increasing. , when the focusing is on, the operating voltage supplied to the spindle motor is increased to increase the rotation speed of the optical disk again.

Thereafter, the control unit 70 lowers the operating voltage applied to the spindle motor again in the focusing-on state to maintain the rotational speed of the optical disk in the increased state without increasing the rotational speed, and then performs a tracking-on operation, In the tracking-on state, the operating voltage is raised again to increase the rotation speed of the optical disk again.

Thereafter, the control unit 70 lowers the operating voltage applied to the spindle motor again in the focusing-on and tracking-on states to maintain the rotation speed of the optical disk in a state in which the rotation speed of the optical disk is increased without increasing the rotation speed, and then the actuator or the sled. The motor (or stepper motor) is controlled to perform a seek operation to move the optical focus to a desired address (or track), and when the optical focus moves to a desired track, the operating voltage is raised again to increase the rotation speed of the optical disk again.

Thereafter, when the rotation speed of the optical disk reaches the target speed, the controller 70 lowers the operating voltage applied to the spindle motor to maintain the rotation speed of the optical disk at the target speed, and performs an optical disk reproduction operation requested by the host. An optical disc recording operation can be performed.

10 is a flowchart illustrating an optical disk driving method according to the present invention.

The control unit 70 checks whether the supplied power is USB power, that is, whether it is connected to the host through the USB interface (S10).

When the optical disk device operates on the USB power source (YES in S10), the controller 70 checks whether the rotation speed of the optical disk is increased to a target speed in an RPM-up period (S11). The controller 70 gradually increases the operating voltage supplied to the spindle motor 11 during the RPM-up period so that the rotational speed of the optical disk can quickly reach the target speed.

When the optical disk device does not operate on the USB power source (NO in S10) or is not in the RPM-up period (NO in S11), the current reduction mode according to the present invention does not need to be applied and thus ends.

In the case of the RPM up section (YES in S11), the control unit 70 performs an access operation (focusing servo, tracking servo, slide It is determined whether the step is to be performed (one of the red servos) (S12).

When the access operation is to be performed (YES in S12), the control unit 70 lowers the driving voltage applied to the spindle motor to maintain the current rotation speed without increasing the rotation speed of the optical disk (S13); On the other hand, when the access operation is not performed (NO in S12), the driving voltage applied to the spindle motor is gradually increased to increase the rotation speed of the optical disk (S14).

The access operation may include a focusing-on operation step, a tracking-on operation step, a sled seek operation step, and a tracking seek operation step.

During each step constituting the access operation, the rotation speed of the optical disk is gradually increased between the steps after one step is completed and before the next step is performed. The level of the operating voltage may also be gradually increased as the steps progress.

That is, when a first voltage is applied to the spindle motor when a focusing-on operation is first performed among the access operations, a second voltage higher than the first voltage is applied to the spindle motor when a tracking-on operation is performed following the focusing-on operation. can Also, a third voltage higher than the second voltage may be applied to the spindle motor when a seek operation is performed following the tracking-on operation.

The control unit 70 checks whether the access operation is over (S15), if the access operation is over (YES in S15), it ends, and if the access operation is not finished (NO in S15), it goes back to step S11 to check whether the RPM up section is go back

If the access operation is finished (YES in S15), the control unit 70 increases the level of the operating voltage supplied to the spindle motor until the rotation speed of the optical disk reaches the target speed to increase the rotation speed of the optical disk again. , when the target speed is reached, the level of the operating voltage is lowered to maintain the rotation speed of the optical disk at the target speed.

11 shows another embodiment of lowering the overall operating current.

In the embodiment of FIG. 11, unlike the embodiment of FIG. 6, only the focusing-on operation is performed among the access operations during the RPM-up period for increasing the rotational speed of the optical disk to the target speed, and after the RPM-up period ends, that is, the optical disk After the rotational speed reaches the target speed and the level of the operating voltage applied to the spindle motor is lowered, tracking-on servo and seek operations are performed to prevent excessive current consumption in servo operation while simultaneously performing RPM up operation and access operation. can be prevented

When the tracking-on operation and the seek operation are performed during the RPM-up period, a problem in that the tracking servo reacts excessively due to a defect in the optical disk and thus the peak current increases may occur. In the embodiment of Figure 11, in order to avoid this problem, the tracking-on operation and the seek operation are performed after the RPM-up period ends.

The embodiment of Fig. 11 can be applied to a data write operation that is not sensitive to the delay time until it responds to a command issued by the host.

On the other hand, when a response delay time to a host command is a problem, such as when audio data or video data stored in an optical disk is reproduced, the access operation is terminated in the RPM up section as shown in the embodiment of FIG. 6 and the rotation speed of the optical disk is the target. It is advantageous to perform the optical disc playback operation immediately after the speed is reached.

When the command transmitted from the host through the interface unit 80 is an optical disk reproduction operation, the control unit 70 performs an RPM up operation and an access operation according to the embodiment of FIG. 6 , and when the command is an optical disk recording operation , after performing the RPM up operation according to the embodiment of FIG. 11 , the remaining part of the access operation may be performed.

Therefore, the optical disk device limits the operating voltage supplied to the spindle motor when performing an access operation in the RPM up section when it is connected to a smart device through a USB interface and operates. This allows the target speed to be reached quickly, while ensuring that the operating current does not exceed the current limit that the USB interface can supply.

The optical disk apparatus and driving method described in this specification can be described as follows.

An optical disk apparatus according to an embodiment includes: a rotation motor for rotating the optical disk; an optical pickup for adjusting an actuator supporting the objective lens in a focusing direction and a tracking direction so that the optical focus is focused on a desired position of the optical disk; a sled motor for moving the optical pickup in the inner and outer circumferential directions of the optical disk; and a driving circuit for driving the optical pickup, the sled motor, and the rotation motor, wherein the driving circuit is configured to focus the optical light at a desired position in a rotation speed increase section in which the rotation speed of the optical disk is increased to a target speed. When performing an access operation, the level of the driving voltage applied to the spindle motor may be lowered.

In an embodiment, the driving circuit may raise the level of the driving voltage again while the access operation is not performed during the rotation speed increase period.

In an embodiment, the driving circuit may decrease the level of the driving voltage so that the rotation speed of the optical disk is kept constant at the same speed as before the access operation is performed while the access operation is performed during the rotation speed increase period.

In one embodiment, the driving circuit is configured to gradually increase the rotational speed of the optical disk while performing the access operation in the rotational speed increasing section, but increase the rotational speed to a lower speed than the increasing speed while the access operation is not performed. It is possible to adjust the level of the driving voltage downward.

In one embodiment, when the access operation consists of the first operation, the second operation and the third operation and the first to third operations are performed in the rotation speed increasing period, the driving circuit is configured to: Applying an operating voltage of a first level to the spindle motor, applying an operating voltage of a second level higher than the first level to the spindle motor while performing a second operation after the first operation, and performing a third operation after the second operation During the operation, an operating voltage of a third level higher than the second level may be applied to the spindle motor.

In one embodiment, the driving circuit, when the access operation consists of the first operation, the second operation and the third operation, performs the first operation in the rotation speed increasing period, and performs the second operation and the third operation at the rotation speed It can be performed after the increment period ends.

In one embodiment, after the rotation speed of the optical disk reaches the target speed and the rotation speed increase period ends, the second operation and the second operation are performed while the level of the driving voltage is lowered to maintain the rotation speed at the target speed. 3 actions can be performed.

In one embodiment, the first operation is a focusing-on operation in which the driving circuit drives the actuator to focus light on a desired data layer, and the second operation is a focusing-on operation in which the driving circuit drives the actuator so that the optical focus follows the track. The tracking-on operation may be a tracking-on operation, and the third operation may be a seek operation in which the driving circuit drives one or more of the actuator and the sled motor to move the optical focus from the current track to the desired track.

According to another exemplary embodiment, a method of driving an optical disk apparatus includes: increasing the rotational speed of the optical disk to a target speed by applying a driving voltage to a spindle motor during a rotational speed increasing period; and lowering the level of the driving voltage while performing an access operation for focusing the light to a desired position during the rotation speed increase period.

In one embodiment, the driving method may further include raising the level of the driving voltage again while the access operation is not performed during the rotation speed increase period.

In an embodiment, the driving method may further include determining whether power is supplied through the USB interface.

The present invention is not limited to the described embodiments, and it is apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. Accordingly, it should be said that such modifications or variations fall within the scope of the claims of the present invention.

10: optical disc 11: spindle motor
12: sled motor 20: optical pickup
30: optical driving unit 40: digital signal processing unit
50: RF unit 60: servo / driving unit
70: control unit 80: interface unit
100: optical disk unit

Claims (14)

a rotation motor for rotating the optical disk;
an optical pickup for adjusting an actuator supporting the objective lens in a focusing direction and a tracking direction so that the optical focus is focused on a desired position on the optical disk;
a sled motor for moving the optical pickup in the inner and outer circumferential directions of the optical disk; and
and a driving circuit for driving the optical pickup, the sled motor, and the rotation motor;
The driving circuit determines the level of the driving voltage applied to the spindle motor when performing an access operation to bring the optical focus to a desired position in a rotation speed increasing section in which the rotation speed of the optical disk is increased to a target speed. An optical disk device characterized in that it is lowered. According to claim 1,
and the driving circuit increases the level of the driving voltage again while the access operation is not performed during the rotation speed increase period. 3. The method of claim 2,
The driving circuit is configured to lower the level of the driving voltage while performing the access operation during the rotation speed increase period so that the rotation speed of the optical disk is kept constant at the same speed as before the access operation is performed. An optical disk device characterized in that. 3. The method of claim 2,
The driving circuit may include, while performing the access operation during the rotation speed increase period, the rotation speed of the optical disk is gradually increased, but increases to a speed lower than the speed at which the rotation speed increases while the access operation is not performed and lowering the level of the driving voltage so as to 3. The method of claim 2,
When the access operation includes a first operation, a second operation, and a third operation, and the first to third operations are performed during the rotation speed increase period, the driving circuit is configured to: applying an operating voltage of a first level to the spindle motor, and applying an operating voltage of a second level higher than the first level to the spindle motor while performing the second operation after the first operation; and applying an operating voltage of a third level higher than the second level to the spindle motor while performing the third operation after operation. 3. The method of claim 2,
The driving circuit may be configured to, when the access operation includes a first operation, a second operation, and a third operation, perform the first operation in the rotation speed increasing period, and perform the second operation and the third operation to rotate An optical disk device, characterized in that the speed increase period is terminated. 7. The method of claim 6,
The driving circuit may include, after the rotation speed of the optical disk reaches the target speed and ends the rotation speed increase period, lowering the level of the driving voltage to maintain the rotation speed at the target speed. An optical disk device, characterized in that an operation and a third operation are performed. 7. The method according to claim 5 or 6,
The first operation is a focusing-on operation in which the driving circuit drives the actuator to focus the optical light on a desired data layer, and the second operation is a focusing-on operation in which the driving circuit drives the actuator in the focusing-on state to achieve the optical focus. a tracking-on operation to follow a track, and the third operation is a seek operation in which the driving circuit drives at least one of the actuator and the sled motor to move the optical focus from a current track to a desired track an optical disk device. increasing the rotation speed of the optical disk to a target speed by applying a driving voltage to the spindle motor during the rotation speed increase period; and
and lowering the level of the driving voltage while performing an access operation for focusing an optical focus on a desired position during the rotation speed increase period. 10. The method of claim 9,
and raising the level of the driving voltage again while the access operation is not performed during the rotation speed increase period. 10. The method of claim 9,
The method of driving an optical disk device, characterized in that it further comprises the step of checking whether power is supplied through the USB interface. 11. The method of claim 10,
The step of lowering the level of the driving voltage,
When the access operation consists of a first operation, a second operation, and a third operation, and the first operation to the third operation is performed in the rotation speed increasing period, the first operation is performed to the spindle motor while the first operation is performed. An operating voltage of one level is applied, and an operating voltage of a second level higher than the first level is applied to the spindle motor while the second operation is performed after the first operation, and the third operation voltage is applied after the second operation and applying an operating voltage of a third level higher than the second level to the spindle motor while an operation is being performed. 11. The method of claim 10,
In the step of lowering the level of the driving voltage, when the access operation consists of a first operation, a second operation and a third operation, the first operation is performed during the rotation speed increase period,
In the driving method, after the rotation speed of the optical disk reaches the target speed and the rotation speed increase period ends, the second driving voltage is lowered to maintain the rotation speed at the target speed. and performing the operation and the third operation. 14. The method of claim 12 or 13,
The first operation is a focusing-on operation of driving an actuator supporting an objective lens to focus the light on a desired data layer, and the second operation is a focusing-on operation of driving the actuator in a focusing-on state so that the light focus follows a track a tracking-on operation, and the third operation is a seek operation of moving the optical focus from a current track to a desired track by driving one or more of a sled motor for moving the actuator and the optical pickup in the inner and outer circumferential directions of the optical disk A method of driving an optical disk device, characterized in that

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