JPH05325113A - Floppy disc drive unit - Google Patents

Abstract

PURPOSE:To ensure reliability of data even for a low power supply voltage. CONSTITUTION:The floppy disc drive unit being driven with power supply voltage of 3.3V or below is provided with an erase head HFE preceding a recording/reproducing head HR/W wherein old data remaining on the magnetic layer ML of a floppy disc is erased by means of the preceding erase head HFE and then a new data is recorded by means of the following recording/ reproducing head HR/W.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floppy disk drive device driven by a power supply voltage lower than 12 V or 5 V (eg 3.3 V or less).

[0002]

2. Description of the Related Art In recent years, as a data recording / reproducing means of a computer, for example, a floppy disk drive device is often provided (built in) in the computer.
In addition, in portable computers such as so-called laptop and notebook computers, it is required to reduce the thickness and size of the computer and to save labor (for example, lower the voltage of a power supply). Therefore, the floppy disk drive device mounted on the portable computer is also conventionally used, for example.
It is required to operate at a lower voltage (for example, 3.3 V or less) from the power supply voltage of V.

[0003]

By the way, in a floppy disk drive device which currently uses a medium (floppy disk) having a recording capacity of 1 Mbytes or 2 Mbytes, when recording data, old data previously recorded is deleted. An overwrite method is used in which new data is overwritten on top.

However, when the power supply voltage of the floppy disk drive device adopting such an overwrite system is lowered to 3.3 V or less as described above, the rising of the recording current is deteriorated, so that the data recording is not performed. It becomes very problematic.

That is, for example, a floppy disk on which data is recorded by a floppy disk drive device having a power supply voltage of 5V is inserted into the floppy disk drive device having a power supply voltage of 3.3V or less, and the floppy disk is attached to the floppy disk. Considering a case where new data is recorded by the overwrite, old data recorded in the deep magnetic layer of the floppy disk cannot be erased in a portion where the recording current does not rise. Therefore, old data remaining in the deep magnetic layer of the floppy disk becomes noise and is superimposed on new data reproduced later (new data is modulated by the old data), and the reliability of the reproduced new data is increased. Will be damaged.

Now, the manner in which noise is newly generated in the data due to the old data will be described with reference to FIGS. 2 and 3.

FIG. 2 shows the recording data DT and the recording current waveform W of the recording / reproducing head based on this recording data. The waveform w _H of the recording current waveform W is
Is a recording current waveform in a floppy disk drive device with a power supply voltage of 5V, and a waveform w _L is a recording current waveform in a floppy disk drive device with a power supply voltage lower than 5V (for example, 3.3V or less). Also,
The recording data DT in FIG. 2 indicates an inverted signal.

Further, FIG. 3 shows a schematic cross section of a floppy disk in which data is recorded by a floppy disk drive device having a power supply voltage of 5V, and a floppy disk drive having a low power supply voltage into which the floppy disk is inserted later. shows a recording / reproducing head H _{R / W} apparatus, and a reproduction voltage waveforms S _N from the recording / reproducing head H _{R / W.} ML in the drawing of FIG. 3 indicates the magnetic layer of the floppy disk, and BF in the drawing of FIG. 3 indicates the base material of the floppy disk. The arrow MA in FIG. 3 indicates the rotation direction of the disk, and the arrow md in FIG. 3 indicates the direction of magnetization of the magnetic layer.

In FIGS. 2 and 3, the polarity of the current in the recording current waveform W is reversed by the rising edge (falling edge in FIG. 2) of the recording data DT.
This change in polarity requires a finite amount of time. Further, in general, when the power supply voltage is low, the rising and falling of the recording current waveform become worse (not sharp) as shown by the waveform w _L in FIG. Further, if the polarity of the recording current is reversed for a long period when the power supply voltage is low, the magnetic field generated from the head gap G of the recording / reproducing head H _{R / W} is also small during this period, and therefore this head is also small. Magnetic layer ML of floppy disk by H _{R / W}
The record to is also shallow.

For this reason, for example, when the floppy disk drive device having the power supply voltage of 5V has magnetized by the old data to the deep layer of the magnetic layer ML of the floppy disk, the floppy disk drive having the low power supply voltage is used. Recording / playback head H of device
Even if it is overwritten by _{R / W} , it becomes impossible to completely erase old data remaining in the deep layer.

[0011] That is, as shown in FIG. 3, a floppy disk previously high old data deep layer of the magnetic layer ML by the power supply voltage floppy disk drive apparatus is saturation recording (recording layer L _O of the old data), When the floppy disk drive device with a low power supply voltage is inserted, since the rising and falling of the recording current is poor as described above, even if new data is overwritten, the new data recording layer L of FIG. Old data cannot be completely erased and remains like _N.

When the floppy disk in which the old data remains in this way is reproduced, the reproduction voltage waveform of the new data remains in the reproduction waveform S _O of the old data which is not erased by the overwrite and remains in the reproduction waveform S _OL. The reproduced waveform S _N is modulated by the above, and includes waveform distortion different from the reproduced waveform of the new data that should be originally obtained.

Therefore, the present invention has been proposed in view of the above situation, and an object of the present invention is to provide a floppy disk drive device capable of maintaining the reliability of data even at a low power supply voltage. It is what

[0014]

DISCLOSURE OF THE INVENTION A floppy disk drive device of the present invention is proposed to achieve the above-mentioned object, and in a floppy disk drive device driven by a power supply voltage of 3.3 V or less, A preceding erase head that precedes the recording / reproducing head that records and reproduces data is provided, data is erased by the preceding erase head, and then data recording is performed by the following recording / reproducing head. It is a thing.

[0015]

According to the floppy disk drive device of the present invention, a direct current is applied to the preceding erase head for erasing data. That is, since the polarity of the current is not reversed like the recording / reproducing head, the preceding erase head can generate a stable erasing magnetic field, and therefore the old data can be completely erased to the deep magnetic layer of the floppy disk. Can be erased.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

The floppy disk drive device of the embodiment of the present invention is a floppy disk drive device driven by a power supply voltage of 3.3 V or less, and as shown in FIG. 1, recording / reproducing for recording and reproducing data. Head H
A preceding erase head H _FE preceding the _{R / W} is provided, and the preceding erase head H _FE is used to form the magnetic layer M of the floppy disk.
After the old data remaining in L is erased, new data is recorded by the recording / reproducing head H _{R / W} in the subsequent line.

In FIG. 1, a schematic cross section of a floppy disk in which data is recorded by a floppy disk drive device having a power supply voltage of 5V, for example, and a power supply voltage to which the floppy disk is inserted later are low ( For example, the recording / reproducing head H _{R / W} and the preceding erase head H _{FE of the} 3.3 V) floppy disk drive device are shown. Further, ML in the drawing of FIG. 1 indicates the magnetic layer of the floppy disk, and BF in the drawing of FIG. 1 indicates the base material of the floppy disk. Further, arrow MA in FIG. 1 indicates the rotation direction of the disk, and arrow md in FIG. 1 indicates the direction of magnetization of the magnetic layer.

Here, the current passed through the preceding erase head H _FE of the floppy disk drive apparatus of this embodiment is a direct current for erasing data, and the data recording by the recording / reproducing head H _{R / W} is performed. It does not reverse the polarity of the current as sometimes. Therefore, the preceding erase head H _FE can generate a stable erasing magnetic field, and thus can completely erase even the deep layers of the magnetic layer ML of the floppy disk.

The preceding erase head H _FE is arranged prior to the recording / reproducing head H _{R / W.}
In other words, in the apparatus of this embodiment, the preceding erase head H _FE erases the direct current to the deep layer of the magnetic layer ML of the floppy disk, and then the recording / reproducing head H
_Since new data will be written by _{R / W} , the influence of old data that has been erased, such as when overwriting in the conventional floppy disk drive device described above, is eliminated.

As described above, according to this embodiment, the data
Recording / reproducing head H for recording and reproducing data_{R / W}Precedes
Erasure head H_FEThe preceding erase
Head H_FERemains in the magnetic layer ML of the floppy disk
Data is erased, and then the subsequent recording / playback operation is performed.
Dead H_{R / W}To record new data in
More, for example, old data is saturated to the depth of the magnetic layer ML.
Recording (recording layer L of old data_O) Being a floppy
The disk is a floppy disk drive with a low power supply voltage in this embodiment.
Even when it is attached to the quad drive device, the recording layer L_Oof
Old data is the above erase head H_FECompletely erase with
Therefore, the recording / reproducing head H _{R / W}With new data
Recording layer L_NCan only be formed on the magnetic layer ML
Become so.

In this embodiment, the recording capacity is 1
Any floppy disk such as M bytes / 2 M bytes / 1.6 M bytes / 4 M bytes can be applied. That is, the recording / reproducing head H for high density recording
_{Even if} the head gap G of _{R / W} is narrow, the recording on the magnetic layer ML becomes shallow, but the preceding erase head H preceding the recording / reproducing head H _{R / W as} in the above-described embodiment. By providing the _FE , old data recorded in the deep layer can be completely erased, so that the influence on newly recorded data can be eliminated.

Further, in the above-mentioned embodiment, the old data is supposed to be recorded by the floppy disk drive device having the power supply voltage of 5V. However, even if the old data is recorded by the floppy disk drive device having the power supply voltage of 12V, The floppy disk drive device of the embodiment is erasable.

[0024]

As described above, according to the floppy disk drive device of the present invention, in the floppy disk drive device driven by the power supply voltage of 3.3 V or less,
A preceding erase head that precedes the recording / reproducing head that records and reproduces data is provided, data is erased by this preceding erase head, and then data recording is performed by the subsequent recording / reproducing head. As a result, the reliability of data can be maintained even with a low power supply voltage.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a main part of a floppy disk drive device according to an embodiment of the present invention and a partial cross section of a floppy disk.

FIG. 2 is a diagram showing two recording current waveforms with different power supply voltages.

FIG. 3 is a diagram for explaining a defect of a conventional floppy disk drive device.

[Explanation of symbols]

HR _{/ W:} Recording / reproducing head H _FE: Leading erase head G: Head gap ML: Magnetic layer BF: Base material

Claims (1)

[Claims] 1. A floppy disk drive device driven by a power supply voltage of 3.3 V or less, wherein a preceding erase head preceding a recording / reproducing head for recording and reproducing data is provided, and the preceding erase head erases data. And then
A floppy disk drive device characterized in that data is recorded by the following recording / reproducing head.