JP2001266451A - Fdd unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To embody the reduction of the number of input and output terminals disposed at an IC for an FDD unit, the reduction of the number of wiring connected to the input and output terminals and the ease of wiring work. SOLUTION: The IC 1 for the FDD unit is provided with an index signal input terminal 1a for receiving the index signal of a spindle motor 103 through a line 3 from the index signal output terminal 2a of the motor driver IC 1. The input of the signal for setting one mode of the two modes to the index signal input terminal 1a is executed in accordance with the on/off state of a jumper land 5 connected between the line 3 and the ground for the specified period after turning on of a power source. The index signal outputted by the motor driver IC 2 is introduced to the index signal input terminal 1a at the point of the time when the specified time elapses.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an IC for an FDD device.
FDD using the index signal input terminal of (integrated circuit for floppy disk drive) as the mode setting terminal
Related to the device.

[0002]

2. Description of the Related Art An FDD (floppy disk drive) device has a host (not shown) as shown in FIG.
Device for FDD device connected via host I / F to
C, a mechanical control IC 101, a motor driver IC 102 for driving a spindle motor operating under the control of the mechanical control IC 101, a spindle motor 103 driven by a drive output from the motor driver IC 102, and an FD (floppy disk) A head 104 for reading and writing data from and
A stepping motor 105 for seeking the position of the head 104 with high precision is provided.

A mechanical control IC 101, which is an IC for an FDD device, has
01, a power supply voltage monitoring unit 106 which constantly monitors a power supply voltage supplied to each circuit, and a clock circuit 107 which outputs a clock signal which is a reference of operation timing of each circuit unit.
And a control circuit 108 for controlling the driving of the spindle motor 103 by the motor driver IC 102.

The control circuit 108 supplies an on / off signal, a rotation speed switching signal, and a clock signal for driving and stopping the driving of the spindle motor 103 by an external command to the motor driver IC 102.
Also, a motor driver IC is provided from the spindle motor 103.
F through the index signal output terminal 102a
An index signal for determining a start point for data writing or the like in D is transmitted to the mechanical control IC 10.
1 to the index signal input terminal 101a,
The data is supplied to the host via the host I / F.

A read / write unit 109 is provided in the mechanism control IC 101 and functions to read and write information on the FD by the head 104. Further, the mechanical control IC 101 is provided with a stepping motor driver section 110 of a stepping motor 105 for seeking the position of the head 104. The stepping motor driver section 110 controls the stepping motor 1 under the control of the control circuit 108.
05 is driven and controlled. The mechanical control IC 10
Mode setting terminal 101 which is a drive specification setting terminal of No. 1
A jumper land 1 for setting one of the two modes of the FDD IC, for example, for setting a drive specification corresponding to the type of the FD, between the b and the ground.
11 are connected. This jumper land 111
It is made electrically conductive by welding the two land portions of the solder constituting the control circuit, and the control circuit is provided through a mode setting terminal 101b as the drive specification setting terminal provided on the mechanical control IC 101 via a line. 108.

Next, the operation of the FDD device having the above configuration will be described. When the power supply to the FDD device is turned on and reaches a certain voltage, the power supply voltage monitoring unit 106 releases the reset of each circuit of the mechanical control IC 101 as the IC for the FDD device. Therefore, the control circuit 108 supplies an on / off signal for driving the spindle motor 103, a rotation speed switching signal, and a clock signal to the motor driver IC 102 in accordance with a command input from the host via the host I / F. Thereby, the drive of the spindle motor 103 is controlled at a predetermined rotation speed and a predetermined synchronization timing. The control circuit 108 controls the driving of the stepping motor 105 so as to accurately seek the position of the head 104.

Further, the control circuit 108 controls the FD
An index signal from the spindle motor 103 for determining a start point for data writing or the like is read from one index signal input terminal 101a of the mechanical control IC 101 and supplied to the host. The read / write unit 109 reads and writes information from and to the area on the FD that has been sought. On the other hand, jumper land 111
Is the mechanical control IC 1 by welding or non-welding.
01 mode setting terminal 101b can set two potentials. Therefore, these two potentials are used for setting two modes, for example, the type of floppy disk (recording density).
Can be used as a potential corresponding to

[0008]

However, in such a conventional FDD device, a mode control terminal 101b for setting the mode and an index signal are received by a mechanical control IC which is an IC for the FDD device. It is necessary to provide the index signal input terminal 101a separately, and this leads to an increase in the number of input / output terminals (pins) of the mechanical control IC and an increase in the number of wirings connected to these terminals. However, there is a problem that the wiring work becomes complicated.

The present invention has been made to solve such a conventional problem, and an object of the present invention is to use an index signal input terminal commonly as an index signal input terminal and a mode setting terminal, thereby achieving FDD. Device I
An object of the present invention is to provide an FDD device capable of reducing the number of input / output terminals provided in C, reducing the number of wirings connected to the input / output terminals, and facilitating wiring work.

[0010]

In order to achieve the above object, an FDD apparatus according to the present invention comprises a motor driver IC for driving a spindle motor, and a motor driver IC for driving the spindle motor.
And an index signal input terminal provided on the FDD device IC and receiving an index signal of the spindle motor through a line from an index signal output terminal of the motor driver IC. A predetermined time after power-on is set by the FDD device IC with respect to the index signal input terminal based on an on / off state of a jumper land connected between the line and the ground. A mode setting signal of one of the two power modes is input, and the index signal output from the motor driver IC is input to the index signal input terminal after the predetermined period has elapsed. .

According to this aspect, the mode change such as the circuit constant based on the magnetic medium density of the FD, for example, which is the drive specification, is performed by the mode setting signal input to the index signal input terminal within a certain time after the power is turned on. On the other hand, after a certain period of time, the index signal input terminal is immediately available for taking in the index signal from the spindle motor.

Further, in the FDD device according to the present invention, the output of the motor driver IC is kept at a high impedance for a certain period after the power is turned on.

According to this aspect, within the predetermined period,
The index signal output from the motor driver IC is prevented from being set in the mode by the jumper land and affecting the mode signal input to the index signal input terminal, so that the mode setting operation in the FDD device IC can be reliably performed. I have to.

In the FDD device according to the present invention, the two modes are provided by two types of voltages applied to an index signal input terminal.

According to this aspect, the selection of the two modes can be made very simply and reliably by a simple circuit configuration and operation which are set in accordance with the potential change due to the opening and short circuit of the line by the jumper land. ing.

Further, in the FDD device according to the present invention, a resistor for providing an intermediate potential for setting one of the two modes is connected between the jumper land and the ground.

According to this aspect, the input to the index signal input terminal of the IC for the FDD device can be made into three states having different levels, whereby the mode setting function can be easily performed by using the index signal input terminal. Making it feasible.

Further, the FDD apparatus according to the present invention comprises an FD
And a stepping motor for seeking the position of the head.

According to this aspect, the FD after the lapse of a predetermined time
In the original operation of the D device, the head reads and writes data to and from the FD driven by the spindle motor, and seeks the position of the head by the stepping motor so that information can be recorded and reproduced with high accuracy. I have to.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an FDD device of the present invention, which is different from that shown in FIG. 3 in that an index signal output terminal 2a of a motor driver IC 2 and an index signal of a mechanical control IC 1 as an IC for the FDD device. The input terminal 1a is connected by a line 3. In this line 3, a jumper land 5 is connected via a resistor 4 between the index signal output terminal 2a, the index signal input terminal 1a and the ground. is there. In addition, the same components as those shown in FIG. 2 are denoted by the same reference numerals, and redundant description will be omitted.

In this embodiment, first, a fixed period immediately after the power is turned on is determined in advance as a reset hold time. This certain period is a sufficient period required for performing mode setting described later, and this period is arbitrarily set by a timer that counts clock pulses. In such a reset hold time, the output of the motor driver IC 2 is set to high impedance, and the mechanical control IC 1 which is an IC for the FDD device is used.
The control circuit 108 recognizes that the reset hold time which is set to the high impedance is a time zone for mode setting. In this time zone, the mechanical control IC 1 determines whether the setting of the jumper land 5 is short or open at the time of manufacturing the FDD device based on the voltage level input to the index signal input terminal 1a. That is, the mechanical control IC 1 selects one of the two setting modes according to the voltage level corresponding to the short or open, and operates the FDD device in the setting mode that is the selected drive specification.

In this case, the jumper land 5 is grounded via the resistor 4. Accordingly, although the potential of the index signal input terminal 1a changes to a binary value in accordance with the open and short of the jumper land 5, the potential at the time of the short does not decrease to 0 volt or near this 0 volt. As shown, the voltage at the time of opening (for example, 3.33 to 5 V (Vcc)) and the ground potential (for example, O
It shows an intermediate level potential (1.67 to 3.33 V) between (GND) and 1.67 V.

When a certain period of time as the reset hold time ends, the operation of the FDD device and the capture of the index signal are performed in the selected setting mode thereafter. When the reset time ends, the mechanical control IC 1 shifts to the normal mode, and the high impedance state of the output of the motor driver IC 2 is released. For this reason, the index signal input terminal 1a functions as a signal input terminal in a normal FDD device driving state, and the spindle motor 10
The high (High) and low (Low) index signals obtained by the rotation of No. 3 are input to the index signal input terminal 1a. That is, it is determined whether or not the index signal has entered. As described above, according to the present invention, the number of terminals provided in the mechanical control IC 1 can be reduced by using the index signal input terminal 1a as the mode setting terminal without separately providing the index signal input terminal and the mode setting terminal. . Therefore, a mechanical control I with many types of mode setting functions
In the case of C1, the number of wirings and the number of man-hours and the wiring cost can be reduced by reducing the number of terminals.

[0024]

As described above, according to the present invention, the fixed time after the power is turned on is determined based on the on / off state of the jumper land connected between the line and the ground, and based on the index signal input terminal. , A mode setting signal of one of two modes to be set by the FDD device IC is input, and at the time when the certain period elapses,
Since the index signal output from the motor driver IC is input to the index signal input terminal, the index signal input terminal is commonly used as an index signal input terminal and a mode setting terminal. And the number of wirings connected to the input / output terminals can be reduced, and the wiring work can be simplified.

Further, according to the present invention, the output of the motor driver IC is maintained at a high impedance for a certain period after the power is turned on. Thus, it is possible to prevent the mode signal from being set in the mode and input to the index signal input terminal, thereby to ensure the mode setting operation in the FDD device IC.

Further, according to the present invention, the two modes are given by two types of voltages applied to the index signal input terminal. With a simple circuit configuration and operation set in accordance with a potential change due to a short circuit, an effect that the operation can be performed extremely simply and reliably is obtained.

According to the present invention, a resistor for providing an intermediate potential for setting one of the two modes is connected between the jumper land and the ground, thereby providing an IC for an FDD device. The input to the index signal input terminal can be made into three states having different levels, thereby providing an effect that the mode setting function can be easily realized by using the index signal input terminal.

Further, according to the present invention, by providing the head for writing data to the FD and the stepping motor for seeking the position of the head, the FD driven by the spindle motor is provided. In this way, data can be read and written by the head, and the position of the head can be sought by the stepping motor, so that information can be recorded and reproduced with high accuracy.

[Brief description of the drawings]

FIG. 1 is a block diagram conceptually showing an FDD device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a mode setting situation by a jumper land in the present invention.

FIG. 3 is a block diagram showing a conventional FDD device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Mechanical control IC (IC for FDD device, integrated circuit for floppy disk drive device) 1a Index signal input terminal 2 Motor driver IC 2a Index signal output terminal 3 Line 4 Resistance 5 Jumper land 103 Spindle motor 104 Head 105 Stepping motor

Claims (5)

[Claims] 1. A motor driver IC for driving a spindle motor, an IC for an FDD device that controls driving of the spindle motor via the motor driver IC, and an index of the motor driver IC provided in the IC for the FDD device. An index signal input terminal for receiving an index signal of the spindle motor from a signal output terminal through a line, and for a predetermined time after power-on, a jumper land connected between the line and ground is turned on / off. First, a mode setting signal of one of two modes to be set by the FDD device IC is input to the index signal input terminal.
An FDD device, wherein the index signal output from the FDD is input to the index signal input terminal. 2. The FDD device according to claim 1, wherein the output of the motor driver IC is kept at a high impedance for a certain period after the power is turned on. 3. The FDD device according to claim 1, wherein the two modes are provided by two types of voltages applied to the index signal input terminal. 4. Between the jumper land and ground,
2. The FDD device according to claim 1, wherein a resistor for providing an intermediate potential for setting one of the two modes is connected. 5. After a lapse of a certain period of time after turning on the power, the F
A head for writing data to an FD driven by the spindle motor under the control of an IC for a DD device, and a stepping motor for seeking the position of the head. Item 2. The FDD device according to Item 1.