JPH0676456A - Disk device operating corresponding to power source voltage - Google Patents

Abstract

(57) [Abstract] [Purpose] With respect to a disk device, the purpose is to perform data transfer normally in response to changes in the rotation speed of the disk medium and changes in the moving speed of the head due to changes in the power supply voltage. And [Structure] First in which the rotation speed changes according to the power supply voltage
Disk medium 1 that is driven by a motor 2 to rotate
And a deceleration characteristic when the head 4 is positioned on a track on the disk medium 1 corresponding to the power supply voltage.
Of the motor 5 and a data writing circuit 7 and a data reading circuit 8 whose constants change according to the rotation speed of the disk medium 1, the rotation speed corresponding to a power supply voltage within a predetermined range. After moving the head 4 to the specified track by moving the head 4 with a deceleration characteristic corresponding to a power supply voltage within a predetermined range, a constant corresponding to the rotation speed of the disk medium 1 is set. It is configured to be used for writing or reading data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor for rotating a disk medium and a disk device in which a power supply voltage supplied to a motor for moving a head is changed, and more particularly, the number of rotations of the disk medium according to the change of the power supply voltage. And a change in the speed at which the head is moved, the disk device that operates in response to the power supply voltage that allows normal data transfer with the host device.

In recent years, small disk devices have been required to have a larger storage capacity and a higher data transfer rate as the computer system has become smaller and has higher performance.
With the advent of portable personal computers and the like, it is required to operate with low power consumption and low voltage.

In a small disk device used for a portable personal computer or the like, a battery or the like is used as a power source for a semiconductor circuit, so that the same power source as the semiconductor circuit can be used for the motor. Is desirable.

Therefore, it is necessary to provide a disk device which can flexibly cope with environmental conditions such as power consumption and operating voltage of a system using the disk device.

[0005]

2. Description of the Related Art In a conventional disk device, power consumption and power supply voltage are fixed depending on the model of the disk device. Therefore, the user needs to select and use the disk device in advance according to the environment of the system to be used.

However, in the conventional disk device, 12V is used as the power supply voltage of the voice coil motor for moving the spindle motor and the head, and 5V or 3V is used for the semiconductor circuit.

By the way, the power supply voltage supplied to the spindle motor and the voice coil motor is the same as that of the semiconductor circuit.
12V for low voltage disk drive using V or 3V
The rotation speed of the spindle motor cannot be increased in comparison with the disk device that uses the disk drive, the rotation speed of the disk medium is low, the rotation waiting time is long, and the maximum speed for moving the head of the voice coil motor is also set low. , Seek time becomes longer and access time becomes much longer.

[0008]

As described above, the conventional low-power-consumption, low-voltage type disk device rotates the currently required disk medium at high speed, enables high-speed movement of the head, and enables high-speed data transfer. It is difficult to provide a high-performance disk device that enables the above.

That is, a high-performance disk device needs to rotate the disk medium at a high speed to shorten the rotation waiting time and the read or write time, and move the head at a high speed to shorten the access time. , For this,
This is because the power supply voltage to be supplied to the spindle motor and the voice coil motor must be increased to increase the power consumption to some extent.

Therefore, since it is necessary to prepare and provide disk devices of different types corresponding to the environment of the system in which the disk device is used, the number of types of disk devices increases, and the disk devices are manufactured. In addition to the inconvenience, the user has to select a disk device having a different format for each system, which is bothersome and inconvenient for maintenance.

In view of the above problems, the present invention reduces the number of rotations of the motor, the access time, the write frequency of data, and the band of the low-pass filter when the voltage supplied to the disk device is low. When operating as a low power consumption disk device and the voltage supplied to the disk device is high, the number of rotations of the motor, the access time, the data writing frequency, and the band of the low-pass filter are increased, It is an object of the present invention to provide a disk device capable of operating as a high performance disk device and to flexibly respond to a supplied power supply voltage.

[0012]

FIG. 1 is a block diagram for explaining the principle of the present invention. The disk device positions a head 4 on a disk medium 1 which is driven and rotated by a first motor 2 whose rotational speed changes according to a power supply voltage and a track on the disk medium 1 corresponding to the power supply voltage. It is provided with a second motor 5 whose deceleration characteristics change when it is driven, and a data writing circuit 6 and a data reading circuit 8 whose constants change according to the rotation speed of the disk medium 1.

The detecting means 10 for detecting the power supply voltage
Based on the detection result of the detection means 10, the rotation speed of the first motor 2 is calculated, the drive circuit 3 of the first motor 2 is controlled, and the deceleration characteristic of the second motor 5 is calculated. Is calculated to control the drive circuit 6 of the second motor 5 and the constants of the data write circuit 7 and the data read circuit 8 are calculated and sent to the data write circuit 7 and the data read circuit 8. And a control means 9 for controlling the operation.

With respect to the disk medium 1 rotating at a rotation speed corresponding to a power supply voltage within a predetermined range, the head 4 has a deceleration characteristic corresponding to a power supply voltage within a predetermined range.
After moving to position on the specified track,
Using a constant corresponding to the rotation speed of the disk medium 1,
Write or read data.

[0015]

With the above configuration, when the power supply voltage is low, the data transfer speed is reduced, but when the power supply voltage is high, the disk drive operates as a low power consumption disk drive.
It is possible to operate as a high-performance disk device having a high data transfer rate, and it is possible to provide a disk device that can flexibly respond to the supplied power supply voltage.

[0016]

1 is a block diagram of a circuit showing an embodiment of the present invention, and FIG. 3 is a diagram showing an example of a model curve.

The data sent from the host device (not shown) enters the format control circuit 22 via the terminal shown in the data of FIG. 2, and corresponds to the clock sent by the variable oscillation circuit 23 to the rotational speed of the disk medium 1. The NRZ signal of the corresponding format is sent to the encoder / decoder 21.

The encoder of the encoder / decoder 21 corresponds to the clock transmitted by the variable oscillation circuit 23,
When this NRZ signal is converted into the RLL code logic 1-7 code, it is sent to the head IC circuit 15.

The head IC circuit 15 switches the write current supplied by the D / A conversion circuit 16 in response to the 1-7 code and supplies the current to the head 4, and the disk medium 1
Write to.

The signal waveform read from the disk medium 1 by the head 4 is sent from the head IC circuit 15 to the AGC circuit 17 and, when amplified by the AGC circuit 17 to a predetermined level, sent to the electric filter 18. It

The electric filter 18 can electrically change the pass frequency band and also serves as an equalizing circuit. Therefore, boost up in the high range can be changed.

The electric wave having the unnecessary frequency band removed by the electric filter 18 and the electromagnetic conversion characteristic corrected is sent to the pulse detection circuit 19. The pulse detection circuit 19 detects the peak position of the received signal waveform, converts it into a pulse, and sends it to the data discrimination circuit 20.

Therefore, the data discrimination circuit 20 creates the 1-7 code from this pulse by the window obtained from the built-in PLL circuit, and the encoder / decoder 21
Send to.

The decoder of the encoder / decoder 21 is
An NRZ signal is created from this 1-7 code and sent to the format control circuit 22. Format control circuit 22
Extracts the data required by the host device from this NRZ signal and transfers it to the host device.

The motor power supply is connected to the spindle motor drive circuit 13 and VCM from the terminals shown in the motor power supply of FIG.
It is supplied to the (voice coil motor) control circuit 14 and the power supply voltage detection circuit 24.

The power supply voltage detection circuit 24 detects the voltage of the motor power supply and sends the detection result to the processor 25. The processor 25 operates by reading the program stored in the ROM 26, and at the time of initialization when the power is turned on, based on the detection result of the power supply voltage detection circuit 24,
The power supply voltage is written in the memory 28.

Then, with this stored power supply voltage,
Calculation of the rotation speed of the spindle motor 12 and the VCM 11
Deceleration characteristics, that is, calculation of a model curve for positioning the head 4 in the shortest time corresponding to the current position of the head 4 and the position of the target track when moving the head 4, and constants of the writing circuit and the reading circuit, that is, The oscillating frequency of the variable oscillating circuit 23, the oscillating frequency serving as the reference of the PLL circuit of the data discriminating circuit 20, and the head 4 sent by the D / A conversion circuit 16.
The write current value, the pass frequency band of the electric filter 18, and the boost-up that are optimum for the flying height are calculated.

Then, based on the calculation result, the spindle motor control circuit 13 is controlled so that the rotation speed of the spindle motor 12 becomes the calculated rotation speed. Then, when a seek command is received from the host device via a signal line (not shown), the VCM control circuit 14 is controlled to move the head 4 according to the model curve calculated by the VCM 11.

Further, the variable oscillating circuit 23 is controlled to oscillate a frequency at which data can be written at a data transfer rate corresponding to the rotation speed of the disk medium 1, and the reference of the PLL circuit of the data discriminating circuit 20. Is set to a frequency at which data can be read at a data transfer rate corresponding to the rotation speed of the disk medium 1, and the cutoff frequency and boost up of the electric filter 18 correspond to the rotation speed of the disk medium 1. Set so that data can be read at the specified data transfer rate.

Further, the D / A conversion circuit 16 is controlled so that the write current sent by the D / A conversion circuit 16 has an optimum value corresponding to the flying height of the head 4. When there is an interrupt from the timer 27, the processor 25 fetches the power supply voltage detection result, and when the power supply voltage read at the initial setting and stored in the memory 28 has fluctuated by a certain value or more, the processor 25 of the spindle motor 12 described above. Rotation speed, VCM1
The deceleration characteristic of No. 1 and the constants of the writing circuit and the reading circuit are calculated, and the above control is performed based on the calculation result.

The processor 11 also calculates the rotation speed of the spindle motor 12, the deceleration characteristic of the VCM 11, and the constants of the write circuit and the read circuit, even when a reset signal is received from a host device (not shown). The above control is performed based on the calculation result.

Next, a method of calculating the rotation speed of the spindle motor 12 will be described. The maximum rotation speed of the spindle motor 12 is proportional to the power supply voltage E. The constant of proportionality is BL, and a constant ratio is K (a number smaller than 1), which is calculated by the following equation.

Rotational Speed ω = K × BL ⁻¹ × E Next, a method of calculating the VCM model curve will be described.
The model curve is given by V = V (X). And
Feed-forward current I _FF that flows during deceleration of VCM 11
Is defined as follows.

I _FF = K (E + BL _VCM × V _VCM ) K is a constant proportional constant, E is a power supply voltage, BL _VCM is a proportional constant, and V _VCM is the speed of the VCM at that time and changes with time. , The position signal sent from the position detection circuit 29 for detecting the head position from the servo information on the disk to the processor 25 through the A / D converter is differentiated.

Then, let C be a constant of proportionality, and V _END and X
_Assuming that _END indicates the final velocity and the final position at the end of seek, that is, when the coarse control is switched to the fine control, the velocity and position of the VCM 11 at this time are calculated by the following equation.

V (0) = V _END X (0) = X _END I _FF (0) = K × E + C × V (0) I _FF (n + 1) = I _FF (n) + C × V (n) V ( n + 1) = V (n) + I _FF (n) × ΔT X (n + 1) = X (n) + V (n) × ΔT + 1/2 × I
_FF (n) × ΔT ² ΔT represents a minute time, and ΔT × n represents the passage of time.
K is a constant smaller than 1 and is a constant necessary for controlling the speed of the VCM 11. C is a constant that is determined by the characteristics of the VCM 11 and the mass of the movable part, and ΔT is set to be sufficiently small, n is increased from 0, and the position X and the speed V with respect to time are obtained, respectively, and according to the power supply voltage E. A table of functions of velocity V and position X can be created.

In this model curve, when the speed is plotted on the vertical axis and the position is plotted on the horizontal axis as shown in FIG. 3, when the power supply voltage is high, the maximum speed increases as shown in FIG. 3 (A). When the power supply voltage is low, the maximum speed becomes low as shown in Fig. 3 (B).

During seek deceleration, VCM current I
_{The VCM} is controlled as follows using this table. I _VCM = I _FF + [V (X _VCM ) −V _VCM ] + correction current V _VCM indicates the speed of the _{VCM 11} at that time, and X _VCM indicates the position of the head 4 from the seek target at that time. Here, the correction current is a correction value such as a mechanical offset force applied to the VCM 11 or a circuit offset current.

Next, a method of calculating the constants of the writing circuit and the reading circuit will be described. Typical of these constants are: write frequency W = ω × D cutoff frequency of the electric filter 18 F = F (ω × D) boost up B = B (ω × D) write current IW = IW (ω × D) And these are the rotation speed ω of the spindle motor 12.
Is given as a function of the recording transfer speed D of the write data when the rotation speed of the spindle motor 12 is constant.

However, it is only given purely as a function and strictly, and the other .about. Need not be so strictly determined. Therefore, ˜ may be set by creating a numerical conversion table according to the rotation speed ω of the spindle motor 12 and referring to the optimum value from the table.

FIG. 4 is a flow chart for explaining the operation of FIG. When the power is turned on, device initialization is performed in step (1) and internal tests are performed in step (2). Then, in step (3), the processor 25 records the power supply voltage in the memory 28.

The processor 25 calculates the rotation speed of the spindle motor 12 in step (4), calculates the model curve in step (5), and then calculates the constants of the writing circuit and the reading circuit in step (6). To do.

The processor 25 then proceeds to step (7).
Then, the spindle motor 12 is started, and the writing or reading process as the disk device is executed in step (8). When the timer 27 generates an interrupt in step (9), the processor 25 checks the power supply voltage in step (10). That is, the detection result of the power supply voltage detection circuit 24 is compared with the power supply voltage at the time of initial setting to check whether the power supply voltage has changed by a certain value or more.

If the fluctuation is equal to or less than the fixed value in step (11), the process proceeds to step (8). If it is larger than the fixed value, it is checked in step (12) whether the command is being executed. If the command is being executed, the process of this command is interrupted in step (13), the interruption information is created in step (14), the rotation speed of the spindle motor 12 is calculated in step (15), and the step ( The model curve is calculated in 16), and then the constants of the write circuit and the read circuit are calculated in step (17), and the process proceeds to step (8).

If the command is not being executed at step (12), the processor 25 shifts to the processing at step (15). Further, when the processor 25 receives the reset signal from the host device in the step (18), it shifts to the processing of the step (15).

[0046]

As described above, the present invention reduces the data transfer rate when the power supply voltage is low, but operates as a disk device with low power consumption, and when the power supply voltage is high, the data transfer rate is high. Since it can be operated as a high-performance disk device, it is possible to provide a disk device that can flexibly respond to the supplied power supply voltage.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating the principle of the present invention.

FIG. 2 is a block diagram of a circuit showing an embodiment of the present invention.

FIG. 3 is a diagram showing an example of a model curve

FIG. 4 is a flowchart illustrating the operation of FIG.

[Explanation of symbols]

 1 Disk Medium 2 First Motor 3, 6 Drive Circuit 4 Head 5 Second Motor 7 Data Writing Circuit 8 Data Reading Circuit 9 Control Means 10 Detecting Means 11 VCM 12 Spindle Motor 13 Spindle Motor Control Circuit 14 VCM Control Circuit 15 Heads IC circuit 16 D / A conversion circuit 17 AGC circuit 18 Electric filter 19 Pulse detection circuit 20 Data discrimination circuit 21 Encoder / decoder 22 Format control circuit 23 Variable oscillation circuit 24 Power supply voltage detection circuit 25 Processor 26 ROM 27 Timer 28 Memory

Claims (1)

[Claims] 1. A disk medium (1) which is rotated by being driven by a first motor (2) whose rotation speed changes according to a power supply voltage, and a disk medium (1) on the disk medium (1) corresponding to the power supply voltage. Second motor (5) whose deceleration characteristics change when the head (4) is positioned on the track of the disk, and a data writing circuit whose constant changes corresponding to the rotation speed of the disk medium (1)
A disk device comprising: (7) and a data read circuit (8), comprising: detection means (10) for detecting a power supply voltage; and the first motor based on the detection result of the detection means (10).
The rotation speed of (2) is calculated to control the drive circuit (3) of the first motor (2), and the deceleration characteristic of the second motor (5) is calculated to calculate the deceleration characteristic of the second motor (5). Drive circuit for motor (5) (6)
And the constants of the data write circuit (7) and the data read circuit (8) are calculated, and the data write circuit (7) and the data read circuit (8) are calculated.
(7) and control means (9) for sending to the data read circuit (8)
Is provided, and the head (4) is moved with a deceleration characteristic corresponding to a power supply voltage within a predetermined range with respect to the disk medium (1) rotating at a rotation speed corresponding to a power supply voltage within a predetermined range. A disk device that operates in response to a power supply voltage, characterized in that data is written or read using a constant corresponding to the rotation speed of the disk medium (1) after being positioned on the specified track. .