JPH01185187A - Magnetic disc device - Google Patents

Abstract

PURPOSE:To need no separate mounting of a reference signal generating circuit, by creating reference signal for controlling a spindle motor, in the internal section of a device. CONSTITUTION:A counter circuit 3A is used for the out-ofcontrol of a spindle motor 11, and so the output 16a of a clock generating circuit 16 which is previously set is frequency-divided, and reference signal 3a is created. By a change- over circuit 13, the reference signal 3a from the counter circuit 3A is applied to a phase comparing circuit 6, and the signal applied to the other magnetic disc device via a driver 14 is switched to the reference signal 3a from the other magnetic disc device, applied to the receiving phase comparing circuit 6 via a receiver 5. As a result, the separate mounting of a reference signal generating circuit is not needed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a magnetic disk device for recording and reproducing information, and in particular, it is a method for synchronizing the asynchronous rotation of magnetic disks that occurs when a plurality of magnetic disk devices are used in parallel. The present invention relates to a magnetic disk device that controls rotation.

[Conventional technology]

FIG. 3 is a block diagram showing the main part configuration of an information processing device using a conventional magnetic disk device. In the figure, la
, lb is a magnetic disk device for recording and reproducing information;
3 is a reference signal generation circuit that generates a reference signal for controlling the rotation of a spindle motor that rotates a magnetic disk; 4
is a controller that controls information read, write, seek, etc. for the magnetic disk.

FIG. 4 is a block diagram showing the detailed configuration of the magnetic disk drives 1a and lb shown in FIG. In the figure, 5 is a receiver that receives and receives the reference signal from the reference signal generation circuit 3 in FIG. A phase comparator circuit that outputs a signal; 7 a low-pass filter that passes only the low frequency component of the output of the phase comparator circuit 6; 8 a voltage-controlled oscillation circuit whose oscillation frequency changes depending on the output voltage of the low-pass filter 7; 9 a voltage-controlled oscillation circuit; A drive circuit 1o that amplifies the output of the controlled oscillation circuit 8 and rotates the spindle motor.
11 is the spindle motor for rotating the magnetic disk 1o, and 12 is a rotation speed detection circuit for detecting the rotation speed of the spindle motor 11 (1 solid plate 10).

Next, the operation will be explained. In FIG. 5, the output (reference signal) 3a of the reference signal generation circuit 3 is a pulse signal with a constant period of -, and is generated, for example, when the power is turned on to the magnetic disk device 1a. The - direction spindle motor 11 gradually increases its rotational speed and follows the course shown in lla of FIG. At this time, the pulse period of the output 12a of the rotation detection circuit 12 decreases as the rotation speed 11a of the spindle motor 11 increases. This is because the number of pulses of the output 12a of the rotation speed detection circuit 12 and the rotation GII of the spindle motor 11 are set in advance to output N(II pulses) when the spindle motor 11 rotates once.

This is because a proportional relationship holds between a and a. When the rotational speed 11a of the spindle motor 11 increases and as a result, there is no difference in period and phase of 9 between the output pulse 12a of the rotational speed detection circuit 12 and the reference signal 3a, the spindle motor 1
1 means that steady rotation has been reached. If the output 12a of the rotation speed detection circuit 12 is slower than the reference signal 3a as shown in FIG. This series of operations, which increases the frequency of the oscillation signal 8a, recovers from rotational delays, and maintains steady rotation, is common to the magnetic disk drives 1a and Ib.

Therefore, since the spindle motors 11 of both magnetic disk drives 1a and lb rotate in synchronization with the same reference signal 3a, it is possible to maintain the same rotation of each magnetic disk 10 between the two magnetic disk drives.

[Problem to be solved by the invention]

However, in the conventional magnetic disk drives 1a, lb, the reference f4 generation circuit 3, which generates the reference signal for controlling the spindle motor 11, is provided separately from the magnetic disk drives 1a, lb. Therefore, the magnetic disk drives 1a, lb and the reference signal generation circuit 3 need to be mounted separately, which increases the mounting area and increases the price of the entire information processing device including the magnetic disk drives 1a, 1b. The problem was that it was easy.

This invention was made in order to solve the above-mentioned problems.It creates a reference signal for controlling the spindle motor inside the device, eliminates the need for separate mounting of a reference signal generation circuit, and minimizes the mounting area as much as possible. It is an object of the present invention to provide a magnetic disk device that can be made smaller and reduce the price of the information processing device as a whole.

[Means to solve the problem]

The magnetic disk device according to the present invention includes a counter circuit 3A that generates a reference signal 3a by frequency-dividing the output of a clock generation circuit 16 provided in advance to be used for purposes other than controlling the motor 11, and a counter circuit 3A that generates a reference signal 3a. Reference signal 3
A switching circuit 13 is provided for switching between supplying signal a to the phase comparator circuit 6 and the other magnetic disk device 2a or 2b and supplying the reference signal 3a from the other magnetic disk device 2a or 2b to the phase comparator circuit 6. It is characterized by:

[Effect]

For example, a counter circuit 3A provided in the magnetic disk drive 2a generates a reference signal 3a for controlling the motor 11 by frequency-dividing the output of the clock generation circuit 16. The switching circuit 13 in the magnetic disk device 2a receives the reference signal 3. When a is switched and set to be applied to the phase comparator circuit 6 and the other magnetic disk device 2b, the magnetic disk device 2a controls the rotation of the motor 11 in the device 2a based on the comparison signal from the phase comparator circuit 6, and The device 2b supplies the reference signal 3a given from the magnetic disk device 2a to the phase comparator circuit 6 in the device 2b, and controls the rotation of the motor 11 in the device 2b based on the comparison signal from the phase comparator circuit 6.

Therefore, both motors 11 rotate in synchronization with each other.

[Embodiments of the invention]

FIG. 1 is a block diagram showing the configuration of a magnetic disk device according to an embodiment of the present invention. In FIG. 1, components corresponding to those shown in FIG. 4 are given the same reference numerals, and their explanations will be omitted. In FIG. 1, 3A is used to control the spindle motor 11 by dividing the output 16a of the clock generation circuit 16, which is provided in advance to be used for purposes other than controlling the spindle motor 11 (for example, controlling a magnetic head). A counter circuit 13 generates and generates a reference signal 3a to be used, and 13 is an output of a receiver 5 that receives reference signals from other magnetic disk drives and a counter circuit 3A.
This is a switching circuit that is switched depending on the setting of a changeover switch 15 for switching between the output and the output. That is, the switching circuit 13 supplies the reference signal 3a from the counter circuit 3A to the phase comparator circuit 6 and also supplies it to another magnetic disk device via the driver 14, and also supplies the reference signal 3a from the other magnetic disk device to the receiver 5. It is used to switch between receiving and feeding the signal to the phase comparison circuit 6 via the .

FIG. 2 is a block diagram showing the configuration of an information processing apparatus using the magnetic disk device of this embodiment.

In the figure, 2'a and 2b are magnetic disk devices having the configuration shown in FIG.
a is the reference signal sent between the magnetic disk device 2a and the magnetic disk device 2b.

Next, the operation will be explained. First, it is assumed that the changeover switch 15 in FIG. 1 is set to ON in the magnetic disk device 2a, and set to OFF in the magnetic disk device 2b. As a result, the switching circuit 13 in the magnetic disk drive 2a provides the reference signal 3a from the counter circuit 3A to the phase comparator circuit 6 and also provides it to the other magnetic disk drive 2b via the driver 14.

The magnetic disk device 2b receives a reference signal 3a from the magnetic disk device 2a via a receiver 5 inside the device. The switching circuit 13 of the magnetic disk device 2b applies the reference signal 3a from the receiver 5 only to the phase comparator circuit 6 by setting the changeover switch 15 to OFF. In this case, in the magnetic disk device 2b, the counter circuit 3A
The reference signal 3a from is not used. After the reference signal 3a is applied to the phase comparison circuit 6, a phase-locked loop circuit consisting of a low-pass filter 7, a voltage controlled oscillation circuit 8, a drive circuit 9, a spindle motor 11 rotation speed detection circuit 12, and a phase comparison circuit 6 , spindle motor 11
The rotation speed is controlled in synchronization with the reference signal 3a. That is,
By forming this loop circuit, the spindle motor 11 always rotates in synchronization with the reference signal 3a.

Note that the detailed operation of each circuit constituting this loop circuit has been described in the prior art, and will therefore be omitted here.

In addition, the magnetic disk device 2a with the changeover switch 15 set to ON receives the output signal 16 of the clock generation circuit 16.
A is divided by a counter circuit 3A to lower the frequency to a predetermined value, and a reference signal 3a is created. As described above, this reference signal 3a passes through the switching circuit 13 and becomes the reference signal for the phase-locked loop circuit, and at the same time, the driver 14
and is given to other magnetic disk devices 2b. As a result, the spindle motor 11 of the I-type disk drive 2a rotates in synchronization with the reference signal 3a, as described above.

In this way, in the magnetic disk drives 2a and 2b, each spindle 7 to 11 is rotated in synchronization with the same reference signal 3a, so that the two magnetic disk drives 2a and 2b are attached to the same spindle motor 11. It is equivalent to rotating two magnetic disks IO, and therefore 2
It becomes possible to control information reading, writing, seeking, etc. for the two magnetic disks 10 in exactly the same way.

For example, even if a magnetic disc on which information is recorded in the magnetic disk device 2a is set in the magnetic disk device 2b and the information is reproduced, the control will not be affected.

〔Effect of the invention〕

As described above, according to the present invention, there is provided a counter circuit that generates a reference signal by frequency-dividing the output of a clock generation circuit provided in advance to be used for purposes other than motor control, and a counter circuit that generates a reference signal by dividing the output of a clock generation circuit that is provided in advance for purposes other than motor control. The configuration includes a switching circuit that switches between supplying the phase comparator circuit and other magnetic disk devices and supplying the reference signal from the other magnetic disk device to the phase comparator circuit, so the reference signal generation circuit can be mounted separately. This makes it possible to reduce the mounting area, reduce the price of the information processing device as a whole, and provide a magnetic disk device with a wide range of applications.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a magnetic disk device according to an embodiment of the present invention, FIG. 2 is a block diagram showing the configuration of main parts of an information processing device using the magnetic disk device of this embodiment, and FIG. The figure is a block diagram showing the main part configuration of an information processing device using a conventional magnetic disk device, FIG. 4 is a block diagram showing the configuration of this conventional magnetic disk device, and FIG. 5 is a spindle motor when the power is turned on. FIG. 6 is a timing chart for explaining how the rotation of the spindle motor follows the reference signal. 2a, 2b...Magnetic disk device, 3A...Counter circuit, 3a...Reference signal, 6...Phase comparison circuit,
9... Drive circuit, 10... Magnetic disk, 11... Spindle motor, 13... Switching circuit, 16...
Clock generation circuit.

Claims (1)

[Claims] A motor that rotates a magnetic disk, a drive circuit that controls the rotation of this motor, and a phase comparison circuit that compares the phase of the rotation speed of the motor with a reference signal and outputs a comparison signal for controlling the drive circuit. A magnetic disk drive comprising: a counter circuit that generates the reference signal by frequency-dividing the output of a clock generation circuit provided in advance for use other than controlling the motor; and a reference signal from the counter circuit. A magnetic disk device comprising: a switching circuit for switching between supplying a reference signal from the other magnetic disk device to the phase comparator circuit and another magnetic disk device, and supplying a reference signal from the other magnetic disk device to the phase comparator circuit. .