JPS626414A - magnetic head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a structure of a magnetic head that can rationally perform a performance test on a magnetic head equipped with a circuit element such as an LSI.

[Background of the invention]

In recent years, as the recording density of magnetic heads has increased, the track width has become narrower and the recording wavelength has become smaller, so there is an increasing need to handle minute signals. Therefore, an integrated circuit element such as an LSI is mounted on the magnetic head to provide an amplification function and a selection function to increase the SIN ratio and improve reliability.

In magnetic disk storage devices, a plurality of heads are attached to a set of disks, for example, two recording/reproducing conversion elements are attached to each disk surface, and two pairs of heads are attached to two opposing surfaces. It is a well-known technology that a total of four recording/reproducing conversion elements are incorporated into one head, and an amplification fist selection operation is performed for these elements by one LSI. By the way, after completing the installation work of the magnetic head, it is desirable to perform a performance test to confirm the function as a unit before installing it in the device. , even if the performance is poor, L
It is difficult to distinguish whether the SI is bad or the head recording/reproducing conversion element is bad, so when performing correction work,
If the performance is still poor, replace or modify the head recording/playback conversion element.
Work efficiency was poor.

[Purpose of the invention]

An object of the present invention is to improve this drawback and provide a magnetic head structure that allows performance inspection and modification work to be carried out in a reasonable manner.

[Summary of the invention]

A flexible cable having a double-sided wiring pattern is placed on the back surface of the slider of the magnetic head, and a circuit element is mounted on the cable. There are two types of flexible cables: one that passes the external lead wire of the magnetic head through the circuit element, and one that does not pass through the circuit element.
Have a street.

[Embodiments of the invention]

This will be explained below using FIG.

The magnetic head consists of a recording/reproducing conversion element section in which a magnetic core is wound with a wire, a slider section, a flexible cable (ppc) placed on the back of the slider section, and an LSI etc. connected to an FPC. The recording/reproducing conversion element section 1 of the magnetic head and the FPC 2 are connected by soldering, and the LSI 3 is mounted on a pad on the FPC 2.A recording current is supplied from the outside (α8.α, I). , (-9α, I),
(α8.α, /).

The signal is transmitted from the terminal (α4.α4/), amplified by the LSI 3, and transmitted to the conversion element 1, where the signal is recorded on the recording medium. Also, the reproduction signal from the recording medium is amplified by LSI5,
It is transmitted to the terminals (αrich, α, /) to (α4.α4I). In the magnetic head of the present invention, the structure of the FPC 2 is changed to adopt a double-sided FPC in which conductors forming signal patterns are present on both the front and back sides of the PPC 2. Pad part 4
The conductors on the front and back sides are connected through through holes, and if the conductor on the back side is represented by a broken line, this conductor is connected directly to the external terminals (bt, 75+/), (bt, b) without passing through the LSI5.
t'), (bs, hs').

(h41'4') K connected. Currently, in magnetic head inspection equipment, terminals (α3.α, /) to (α4.α
, /) is connected to a circuit without a recording/reproducing amplifier, and the terminal (I[) connected to terminals (bt, bt') to (b4+64') has a recording/reproducing amplifier. If a performance abnormality is detected at terminal (I), if the test result on the terminal (IFJ side is normal), it will be immediately known that LSI3 is abnormal, and LSI3
All you have to do is replace or repair. In this way, performance inspection and replacement/repair can be carried out rationally. Also, terminal (" and terminal (
Since the performance deviation in 1) can be investigated, even if there is a performance deviation of the head, the gain of the LSI mounted on the head can be measured when the LSI built in the inspection equipment is used as the master.

In addition, when such an FPC performs a bending motion as the head accesses the information track, it is desirable that the conductor be thinner, so the two FPCs are connected with the pad part 4, and the single unit performance test is completed using the above method. The FPC on the dotted line conductor side may be cut at a portion that does not cover the rear bending portion. Also, the conductor thickness can be reduced (
Or, if you leave the broken line conductor by optimizing the bending radius of the device, even if the LSI deteriorates and becomes defective during long-term use of the magnetic head, the terminals (b, , b
, t) to ("4.'4"), by connecting an IC to the defective track, it becomes possible to extract reproduction information.

〔Effect of the invention〕

According to the present invention, it is possible to easily determine whether a failed part or a part with degraded performance is a recording/reproducing conversion element of a magnetic head or a circuit element.

[Brief explanation of drawings]

FIG. 1 is a model representation of the structure of a head according to the present invention. 1... Recording/reproduction conversion element section 2... PPC section 6... LSI section 4... Through-hole pad section 5... Pad section

Claims (1)

[Claims] 1. In a magnetic head equipped with a circuit element, the circuit element is mounted on a pad part on a flexible cable, and the circuit element is connected through a through hole to the side of this pad part corresponding to the head recording/reproducing conversion element part, and the circuit element is connected via the circuit element. A magnetic head characterized by arranging a conductive pattern from which a signal from the magnetic head can be extracted without using the magnetic head.