KR100392797B1 - Apparatus for reducing line noise in hard disk drive - Google Patents

Abstract

PURPOSE: An apparatus for reducing a line noise in a hard disk drive is provided to reduce a line noise by mounting a read/write channel circuit at an FPC together with a preamplifier. CONSTITUTION: A preamplifier(16) mounted at an FPC(Flexible Printed Circuit) preamplifies a signal picked up by a magnetic head(14) in read, and applies the amplified analog read signal to a read/write channel circuit(18) mounted at the FPC. In write, the write current is applied to the magnetic head for writing data on a magnetic disk(12). In read, the read/write channel circuit receives the analog read signal from the preamplifier for transfiguring waveform, and generates a signal encoded by a peak detector for transmitting the signal to a DDC(Disk Data Controller)(26). In write, write data transmitted from a host computer is transmitted to the read/write channel circuit, and the read/write channel circuit encodes the write signal for applying the encoded signal to the preamplifier.

Description

Line Noise Reduction Device in Hard Disk Drive

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hard disk drive, and more particularly, to a line noise reduction device of a hard disk drive.

Typically, a hard disk drive is composed of a head disk assambly (HDA) and a printed circuit board assambly (PCBA). The HDA is composed of a spindle motor, an actuator, a voice coil motor (VCM), a magnetic disk, and a magnetic head. The PCBA consists of a preamplifier, a read / write channel, a DDC (Disk Data Controller), a VCM driver, a spindle motor driver, a microcontroller, a ROM, and a buffer RAM.

On the magnetic disk there is provided a magnetic head (or transducer) for writing or reading data. The magnetic head flies over the track on the magnetic disk. In trek searching, the actuator moves the magnetic head radially on the magnetic disk, and in tracking the track, the actuator is fixed on the corresponding track of the magnetic disk. Typically, magnetic disks are stacked and installed on one spindle, and each magnetic disk surface corresponds to one magnetic head. All magnetic heads are moved together by the actuator.

Generally, in the hard disk drive apparatus, a read signal is applied to a magnetic head in order to read data on a magnetic disk, and an analog signal read from the magnetic disk by the magnetic head is received as an input and processed. In addition, the signal generated by the magnetic head due to the magnetic change on the magnetic disk during reading is very weak. At this time, while the signal generated by the magnetic head is transmitted to the magnetic disk controller, not only a lot of noise is introduced due to the movement of the actuator, the electrical resistance on the transmission path, but also the signal is attenuated.

The analog read signal generated by the magnetic head is amplified by the pre-amplifier of the PCBA, and the amplified signal is applied to the read / write channel. Preferably, the preamplifier is installed as close to the magnetic head as possible. This is because the longer the distance between the magnetic head and the preamplification period is, the more noise is introduced before the analog lead signal generated by the magnetic head is amplified and the attenuation of the analog lead signal is increased.

The read / write channel converts the analog read signal amplified by the preamplifier into a digital read signal and applies it to the DDC.

In order to reduce the distance between the magnetic head and the preamplifier to reduce the influx of noise that may occur between the magnetic head and the preamplifier, the preamplifier is conventionally mounted on the flexible printed circuit (FPC) of the HDA. Thus, the preamplifier mounted on the HDA's FPC pre-amplifies the weak analog read signal read from the magnetic head, and the amplified analog read signal is burned down to the read / write channel mounted on the PCBA. The analog read signal transmitted is decoded, converted into a decoded read signal, and applied to the DDC. However, there was still a problem that noise was introduced while the analog read signal amplified by the preamplifier was transmitted. In addition, since the preamplifier and the lead / right channel are composed of different elements, there is a problem in that the countermeasure against effective line noise is insufficient.

Accordingly, an object of the present invention is to provide an apparatus for reducing the inflow of line noise during transmission of a signal read or written in a hard disk drive.

The present invention for achieving the above object is characterized in that in the hard disk drive device to mount the read / write channel mounted on the PCBA on the FPC of the HDA.

As another method for achieving the above object, the preamplifier and the lead / right channel may be integrated in a hard disk driving apparatus and configured as a single chip and mounted on the HDA.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, it should be noted that like elements in the drawings represent like reference numerals wherever possible. In addition, many specific details are set forth in order to provide a more thorough understanding of the present invention, such as in the following description and the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. And a detailed description of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

1 is a block diagram of a hard disk drive device. The HDA 10 is composed of a magnetic disk 12, a magnetic head 14, a preamplifier 16, a lead / right channel circuit 18, a VCM 20, and a spindle motor 22. The PCBA 24 is composed of a DDC 26, a microcontroller 28, a VCM driver 30, a spindle motor driver 32, a ROM 34, and a buffer RAM 36. 2 shows an actuator assembly of a hard disk. The actuator assembly consists of a magnetic head 14, an actuator 38, a support arm 40, a suspension 42, and an FPC 44.

An operation of the hard disk driving apparatus according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2. The magnetic disk 12 is rotated by the spindle motor 22. The magnetic head 14 is located on the magnetic disk 12, reads data recorded on the magnetic disk 12 at the time of reading, and writes data on the surface of the magnetic disk 12 at the time of writing.

The preamplifier 16 mounted on the FPC 44 preamplifies the signal picked up by the magnetic head 14 at the time of read, and the read / write mounted on the FPC 44 continuously with the preamplifier 16. The amplified analog read signal is applied to the channel 18. In addition, the amplified read signal is applied to the read / write channel 18. On the other hand, during writing, the write current generated by converting the current direction according to the encoded data applied from the read / write channel 18 is applied to the magnetic head 14 to be written on the magnetic disk 12. Write onto the disc 12 via the head 14 of the printhead. The read / write channel circuit 18 mounted on the FPC 44 receives an analog read signal from the preamplifier 16 at the time of reading, waveforms it through a differentiator, generates a signal encoded by a peak detector, and generates a DDC ( 26). At the time of writing, the write data transmitted from the host computer is transmitted from the DDC 26 to the read / write channel 18, and the read / write channel 18 encodes the write signal and applies it to the preamplifier 26. In general, since the digital signal has less influence on noise than the analog signal, the line noise introduced during transmission can be reduced by reducing the distance over which the analog signal is transmitted. The DDC 26 transmits data received from the host computer to the read / write channel circuit 18 or transmits a signal transmitted by the read / write channel 18 to the host computer. The buffer RAM 36 temporarily stores data transmitted between the host computer and the microcontroller 28 and the read / write channel circuit 18. The microcontroller 28 controls the DDC 26 in response to read or write commands received from the host computer and controls track search and track following. The ROM 34 stores the execution program of the microcontroller 28 and various setting values. The VCM driver 30 generates a driving current for driving the actuator 36 by a signal for controlling the position of the magnetic heads 14 generated from the microcontroller 28 to the VCM 20 of the actuator 36. Is authorized. The actuator 36 moves the magnetic head 14 on the magnetic disk 12 in correspondence with the direction and level of the drive current applied from the VCM driver 30. The spindle motor driver 32 drives the spindle motor 22 to rotate the magnetic disk 12 according to a control value for rotation control of the magnetic disk 12 generated from the microcontroller 28.

In another embodiment, the preamplifier 16 and the read / write channel 18 are configured as one-chip ICs. A description will be given with reference to a block diagram of a hard disk drive device implemented with the preamplification and read / write channel ICs 46 shown in FIG. In the hard disk drive apparatus according to this embodiment, the first HDA 46 is composed of a magnetic disk 12, a magnetic head 14, a preamplification and a read / write channel circuit, a VCM, and a spindle motor 22. The PCBA 24 is composed of a DDC 26, a microcontroller 28, a VCM driver 30, a spindle motor driver 32, a ROM 34, and a buffer RAM 36.

Although the preamplifier 16 and the read / write channel 18 are mounted together on the FPC 42 in the above-described embodiment, the analog read signal applied from the preamplifier 16 to the read / write channel 18 or Since the line noise is caused when the analog light signals applied from the read / write channel 18 to the preamplifier 16 are interfaced with each other, the use of the preamplifier and the read / write channel 46 reduces the line noise between the two circuits. . In addition, the mounting area is reduced compared to mounting the preamplifier 16 and the lead / right channel 18 on the FPC, respectively.

Therefore, as described above, in the present invention, when the read / write channel 18 is mounted together with the preamplifier 16 mounted on the FPC 42 and the FPC 42 in the hard disk drive, It offers the advantage of reducing line noise.

In addition, the preamplifier 16 and the read / write channel 18 are implemented in one chip and mounted on the FPC 42, so that the preamplifier 16 and the read / write channel 18 are mounted in separate devices. This has the advantage of reducing line noise and reducing the mounting area.

Meanwhile, in the above description of the present invention, specific embodiments have been described, but various modifications can be made without departing from the scope of the present invention. Therefore, the scope of the invention should not be defined by the described embodiments, but should be defined by the equivalents of the claims and the claims.

1 is a block diagram of a hard disk drive apparatus according to an exemplary embodiment of the present invention.

2 shows an actuator assembly in a hard disk drive.

3 is a block diagram of a hard disk drive apparatus according to another embodiment of the present invention.

Explanation of symbols for the main parts of the drawings

10: IDA (Head Disk Assambly) 12: Magnetic Disk

14: Magnetic Head 16: Preamplifier

18: Lead / Light Channel 20: VCM (Voice Coil Motor)

22: spindle motor 24: PCBA

26: disk data controller 28: microcontroller

30: VCM drive part 32: spindle motor drive part

34: Romans 36: Buffer RAM

38: Actuator 40: Support Arm

42: suspension 44: flexible printed circuit (FPC)

45: first HDA 48: preamplification and lead / right channel

Claims (4)

In the line noise reduction device of the hard disk drive device, A preamplifier for preamplifying the signal generated from the magnetic head, A line noise reduction device, characterized in that a pre-amplified data conversion and a read / write channel IC applied to the PCBA is installed in the HDA. 2. The apparatus of claim 1, wherein the preamplifier and the read / write channel IC are mounted on an FPC of the HDA. In the line noise reduction device of the hard disk drive device, A line noise reduction device comprising preamplifying a signal generated from a magnetic head, converting preamplified data, and applying the preamplification and read / write channel ICs to a disk data controller in the HDA. 4. The apparatus of claim 3, wherein the preamplification and read / write channel ICs are mounted on the FPC of the HDA.