JPH0855314A - DC resistance inspection method for magnetoresistive head - Google Patents
DC resistance inspection method for magnetoresistive headInfo
- Publication number
- JPH0855314A JPH0855314A JP21531794A JP21531794A JPH0855314A JP H0855314 A JPH0855314 A JP H0855314A JP 21531794 A JP21531794 A JP 21531794A JP 21531794 A JP21531794 A JP 21531794A JP H0855314 A JPH0855314 A JP H0855314A
- Authority
- JP
- Japan
- Prior art keywords
- head
- resistance
- tester
- voltage drop
- magnetoresistive
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B2005/0002—Special dispositions or recording techniques
- G11B2005/0005—Arrangements, methods or circuits
- G11B2005/001—Controlling recording characteristics of record carriers or transducing characteristics of transducers by means not being part of their structure
- G11B2005/0013—Controlling recording characteristics of record carriers or transducing characteristics of transducers by means not being part of their structure of transducers, e.g. linearisation, equalisation
- G11B2005/0016—Controlling recording characteristics of record carriers or transducing characteristics of transducers by means not being part of their structure of transducers, e.g. linearisation, equalisation of magnetoresistive transducers
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/455—Arrangements for functional testing of heads; Measuring arrangements for heads
Landscapes
- Magnetic Heads (AREA)
Abstract
(57)【要約】
【目的】 磁気抵抗ヘッド（ＭＲヘッド12）の直流抵抗
Ｒの検査を自動化する。
【構成】 ＭＲヘッド12のインピーダンス特性などを検
査するヘッドテスターに対して、高入力インピーダンス
を有する電圧降下検出回路８を付加し、これと、ヘッド
テスターの有する信号処理回路73およびＣＰＵ５とによ
り、各ＭＲヘッド12の直流抵抗Ｒを順次に検査する。
(57) [Summary] [Purpose] To automate the inspection of the DC resistance R of the magnetoresistive head (MR head 12). [Structure] A voltage drop detection circuit 8 having a high input impedance is added to a head tester for inspecting the impedance characteristics of the MR head 12, and the signal processing circuit 73 and the CPU 5 included in the head tester each The DC resistance R of the MR head 12 is sequentially inspected.
Description
【０００１】[0001]
【産業上の利用分野】この発明は、ヘッドテスターにお
ける磁気抵抗ヘッド（ＭＲヘッド）の直流抵抗の検査方
法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting a DC resistance of a magnetoresistive head (MR head) in a head tester.
【０００２】[0002]
【従来の技術】磁気ディスクに対する磁気ヘッドは薄膜
化により小型軽量とされ、さらに最近においては、デー
タの読出し用にはＭＲヘッドが専ら使用されつつある。
ただし書込み用には、従来と同様にコイル形式の薄膜ヘ
ッドが使用される。ＭＲヘッドはパーマロイを素材とし
て形成され、パーマロイの抵抗値が磁界強度により変化
することを利用したもので、ディスクの磁界変化を検出
してデータを読出すものである。図２は磁気ヘッド１の
外観を示し、磁気ヘッド１はスライダー10と、その溝の
図示の位置にそれぞれ固定された、書込み用のコイルヘ
ッド11と、読出し用のＭＲヘッド12などよりなる。磁気
ヘッド１は製造後、その性能がヘッドテスターにより検
査される。検査項目には、スライダー10の浮上特性や、
コイルヘッド11の書込み性能、またはＭＲヘッド12のイ
ンピーダンス特性と電磁変換特性などの各種がある。2. Description of the Related Art A magnetic head for a magnetic disk is made smaller and lighter by thinning it, and more recently, an MR head is being used exclusively for reading data.
However, for writing, a coil type thin film head is used as in the conventional case. The MR head is made of permalloy as a material, and utilizes the fact that the resistance value of permalloy changes depending on the magnetic field strength, and reads the data by detecting the change in the magnetic field of the disk. FIG. 2 shows the appearance of the magnetic head 1. The magnetic head 1 is composed of a slider 10, a writing coil head 11 and a reading MR head 12 which are fixed to the illustrated positions of the sliders. After the magnetic head 1 is manufactured, its performance is inspected by a head tester. The inspection items include the flying characteristics of the slider 10 and
There are various types such as the writing performance of the coil head 11 or the impedance characteristics and electromagnetic conversion characteristics of the MR head 12.
【０００３】図３はヘッドテスターの概略の構成を示
し、これによるＭＲヘッド12のインピーダンスと電磁変
換の両特性の検査方法を説明する。(a) において、磁気
ディスク２はスピンドル３に装着されて回転し、これに
対して、被検査の磁気ヘッド１は、ハンドリング機構に
よりキャリッジ機構４に装着されて、ディスク２の半径
方向に移動する。(b) は測定部の構成を示し、ＣＰＵ５
と書込み回路６および演算処理部７よりなる。ＣＰＵ５
の指令により、書込み回路６よりコイルヘッド11に対し
てテスト信号が送出されて、ディスク２のトラックに順
次に書込まれ、これがＭＲヘッド12により読出しされ
る。読出し信号は演算処理部７のコンデンサ71により直
流成分が除去されて差動アンプ72に入力し、これより読
出し信号の電圧ｖに対する信号が出力され、両信号は信
号処理回路73に入力して、電磁変換特性が求められ、こ
れらのデータはＡ／Ｄ変換器74によりデジタル化されて
ＣＰＵ５に入力し、それぞれに対する基準値に比較され
て良否が自動検査されている。FIG. 3 shows a schematic structure of a head tester, and a method of inspecting both the impedance and electromagnetic conversion characteristics of the MR head 12 will be described. In (a), the magnetic disk 2 is mounted on the spindle 3 and rotates, while the magnetic head 1 to be inspected is mounted on the carriage mechanism 4 by the handling mechanism and moves in the radial direction of the disk 2. . (b) shows the configuration of the measuring unit, and the CPU 5
And a writing circuit 6 and an arithmetic processing unit 7. CPU5
Command, a test signal is sent from the writing circuit 6 to the coil head 11 to sequentially write the tracks on the track of the disk 2, and the MR head 12 reads the test signal. The read signal has its DC component removed by the capacitor 71 of the arithmetic processing unit 7 and is input to the differential amplifier 72, from which a signal corresponding to the voltage v of the read signal is output, and both signals are input to the signal processing circuit 73, The electromagnetic conversion characteristics are obtained, and these data are digitized by the A / D converter 74 and input to the CPU 5, and compared with the reference value for each, and the quality is automatically inspected.
【０００４】上記のＭＲヘッド12は、直流のバイアス電
流を与えることにより動作するもので、しかも、磁界に
対する検出感度はバイアス電流の値に依存して変化する
ので、検出感度を最適にするために適切なバイアス電流
を与えることが必要とされている。図４は、ＭＲヘッド
12のバイアス電流に対する感度特性を説明するもので、
(a) は、横軸をバイアス電流Ｉおよび磁界強度ｍとし、
縦軸は両者に対する感度特性曲線を示し、曲線の傾斜が
急であるほど検出感度が大きい。例えば、バイアス電流
Ｉが０のときは、変化する磁界強度ｍに対する出力電流
ｉ0 は微小であるが、傾斜が急な点ｐに対応したバイア
ス電流ＩS または−ＩS では、出力電流ｉSは図示のよ
うに大きくなる。そこで(b) のように、ＭＲヘッド12の
両端に所定の直流電圧（Ｅ／２）をそれぞれ加えて適切
なバイアス電流ＩS を供給し、検出感度を最適に設定す
る仕組みとされている。The above-mentioned MR head 12 operates by applying a DC bias current, and since the detection sensitivity to a magnetic field changes depending on the value of the bias current, the detection sensitivity is optimized. It is necessary to provide a proper bias current. Figure 4 shows the MR head
It explains the sensitivity characteristics to 12 bias currents.
In (a), the horizontal axis represents the bias current I and the magnetic field strength m,
The vertical axis represents the sensitivity characteristic curve for both, and the steeper the curve, the greater the detection sensitivity. For example, when the bias current I is 0, the output current i 0 with respect to the changing magnetic field intensity m is very small, but at the bias current I S or −I S corresponding to the point p where the slope is steep, the output current i S Becomes larger as shown. Therefore, as shown in (b), a predetermined DC voltage (E / 2) is applied to both ends of the MR head 12 to supply an appropriate bias current I S , and the detection sensitivity is set optimally.
【０００５】[0005]
【発明が解決しようとする課題】さて多数のＭＲヘッド
12には、パーマロイの抵抗のムラなどより、それぞれの
直流抵抗Ｒにバラツキがあり、このために上記の所定の
電圧Ｅによるバイアス電流Ｉにもバラツキが生じて、検
出感度が最適に設定されない場合がある。これに対して
従来は、別個に測定器を設けて各ＭＲヘッドの直流抵抗
Ｒを測定し、これが基準値の許容範囲外のものは不良と
して破棄し、許容範囲内の良品のみが、ヘッドテスター
に装着されて上記の両特性が検査されている。しかし、
別個の測定器により直流抵抗Ｒを測定する場合は、この
測定器に対する各磁気ヘッド１の着脱と測定の手間が必
要である。そこで、上記のヘッドテスターに直流抵抗測
定回路を付加してＭＲヘッド12の直流抵抗Ｒを測定し、
ＣＰＵ５によりその良否を自動判定すれば、検査は自動
化されて効率的である。この場合、ヘッドテスターの信
号処理回路73はインピーダンスを算出する機能を有し、
またＣＰＵ５は両特性の良否を判定する機能を有するの
で、両機能を直流抵抗Ｒの算出と良否の判定に利用すれ
ば、これらに対する格別な手段が不要で好都合である。
この発明は上記に鑑みてなされたもので、ヘッドテスタ
ーに直流抵抗測定回路を付加し、これによりＭＲヘッド
の直流抵抗の検査を自動化した検査方法を提供すること
を目的とする。A large number of MR heads are now available.
In No. 12, when the direct current resistance R varies due to the unevenness of permalloy resistance, etc., the bias current I due to the above predetermined voltage E also varies, and the detection sensitivity is not optimally set. There is. On the other hand, conventionally, a separate measuring device is provided to measure the DC resistance R of each MR head, and those outside the allowable range of the reference value are discarded as defective, and only good products within the allowable range are tested by the head tester. Both of the above properties have been tested by being mounted on a. But,
When the DC resistance R is measured by a separate measuring device, it is necessary to attach / detach each magnetic head 1 to / from this measuring device and to measure it. Therefore, a DC resistance measuring circuit is added to the above head tester to measure the DC resistance R of the MR head 12,
If the quality is automatically determined by the CPU 5, the inspection is automated and efficient. In this case, the signal processing circuit 73 of the head tester has a function of calculating impedance,
Further, since the CPU 5 has a function of judging pass / fail of both characteristics, if both functions are used for calculation of the DC resistance R and judgment of pass / fail, no special means for these is required, which is convenient.
The present invention has been made in view of the above, and an object thereof is to provide an inspection method in which a direct current resistance measuring circuit is added to a head tester to automate the inspection of the direct current resistance of an MR head.
【０００６】[0006]
【課題を解決するための手段】この発明は、ＭＲヘッド
の直流抵抗検査方法であって、前記のヘッドテスターに
対して、高入力インピーダンスを有する電圧降下検出回
路よりなる直流抵抗測定回路を付加する。ヘッドテスタ
ーにＭＲヘッドを順次に装着してバイアス電流を供給
し、電圧降下検出回路により、各ＭＲヘッドの電圧降下
を検出し、検出電圧を信号処理回路により処理して、各
ＭＲヘッドの直流抵抗を順次に算出し、算出データをＣ
ＰＵ入力して、これに設定された基準値にそれぞれ比較
し、直流抵抗の良否を順次に判定するものである。The present invention is a method for inspecting DC resistance of an MR head, wherein a DC resistance measuring circuit comprising a voltage drop detecting circuit having a high input impedance is added to the head tester. . The MR heads are sequentially attached to the head tester to supply a bias current, the voltage drop detection circuit detects the voltage drop of each MR head, the detected voltage is processed by the signal processing circuit, and the DC resistance of each MR head is detected. Is calculated sequentially, and the calculated data is C
PU is input, and each is compared with the reference value set to this, and the quality of DC resistance is judged sequentially.
【０００７】[0007]
【作用】上記の直流抵抗検査方法においては、ヘッドテ
スターに順次に装着されたＭＲヘッドは、ヘッドテスタ
ーに付加された電圧降下検出回路により、電圧降下が検
出される。検出信号は信号処理回路により処理されて、
各ＭＲヘッドの直流抵抗が順次に算出され、算出された
直流抵抗のデータはデータ処理部に入力して、これに設
定された基準値に比較されて良否が自動判定される。不
良と判定されたＭＲヘッドは破棄され、良品のＭＲヘッ
ドは、引き続いてインピーダンスと電磁変換の両特性が
測定されて検査される。上記において、電圧降下検出回
路は入力インピーダンスが高いので、ＭＲヘッドのイン
ピーダンスと電磁変換の両特性の測定には影響しない。
以上のように、ＭＲヘッドの直流抵抗の測定と検査は自
動化されるので、従来の別個の測定器の場合に必要とさ
れた、磁気ヘッドの着脱と測定の手間が省略されて検査
が効率化される。In the above-described DC resistance inspection method, the MR head sequentially mounted on the head tester detects the voltage drop by the voltage drop detection circuit added to the head tester. The detection signal is processed by the signal processing circuit,
The DC resistance of each MR head is sequentially calculated, and the calculated DC resistance data is input to the data processing unit and compared with the reference value set therein to automatically determine the quality. The MR head determined to be defective is discarded, and the good MR head is subsequently inspected by measuring both impedance and electromagnetic conversion characteristics. In the above, since the voltage drop detection circuit has a high input impedance, it does not affect the measurement of both characteristics of the MR head impedance and electromagnetic conversion.
As described above, since the measurement and inspection of the DC resistance of the MR head are automated, the work of attaching and detaching the magnetic head and the measurement, which are required in the case of the conventional separate measuring device, are omitted, and the inspection is efficient. To be done.
【０００８】[0008]
【実施例】図１は、この発明を適用したヘッドテスター
の構成を示す。ヘッドテスターは、前記した図３と同一
構成とし、同一構成要素は同一番号とする。この発明に
おいては、ヘッドテスターに対して、電圧降下検出回路
８を付加して直流抵抗測定回路を構成し、ＣＰＵ５には
直流抵抗Ｒの基準値ＲS を設定する。電圧降下検出回路
８は、ＭＲヘッド12の両端子にそれぞれ接続された、高
い入力インピーダンスを有する２個のオペアンプ81a,81
b と、これらの出力側に接続された、減算絶対値を出力
するオペアンプ82よりなる。オペアンプ82の出力側を信
号処理回路73に接続する。または、オペアンプ82の出力
は直接Ａ／Ｄ変換器74に入力してもよい。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the structure of a head tester to which the present invention is applied. The head tester has the same configuration as that in FIG. 3 described above, and the same components have the same numbers. In the present invention, the DC drop measuring circuit 8 is added to the head tester to form a DC resistance measuring circuit, and the reference value R S of the DC resistance R is set in the CPU 5. The voltage drop detection circuit 8 is composed of two operational amplifiers 81a and 81a having high input impedance, which are respectively connected to both terminals of the MR head 12.
b, and an operational amplifier 82 connected to these outputs for outputting the subtracted absolute value. The output side of the operational amplifier 82 is connected to the signal processing circuit 73. Alternatively, the output of the operational amplifier 82 may be directly input to the A / D converter 74.
【０００９】以下、上記のヘッドテスターにおける、Ｍ
Ｒヘッド12の直流抵抗Ｒの測定と検査の手順を説明す
る。磁気ヘッド１をディスク２の表面より適当な高さに
保持して、ＭＲヘッド12をＤＣ的に分離する。ついで定
電流回路９によりバイアス電流Ｉを流し、電圧降下が生
じ、これが２個のオペアンプ81a,81b に入力して、ＭＲ
ヘッド12のそれぞれの端子電圧が検出され、これらがオ
ペアンプ82により減算絶対値で出力されて、電圧降下Ｅ
が出力され、信号処理回路73に入力する。バイアス電流
Ｉは定電流回路９によりあらかじめある値に設定してあ
り、測定された電圧降下Ｅとにより、両者の比Ｅ／Ｉ、
すなわち直流抵抗ＲがＣＰＵ５により算出される。これ
に設定されている基準値ＲS と比較されてその良否が判
定されて検査される。以上の手順により各ＭＲヘッド12
は順次に自動検査され、不良と判定されたＭＲヘッド12
は破棄され、良品に対して、引き続き電磁変換特性が測
定されて検査される。Hereinafter, in the above head tester, M
The procedure for measuring and inspecting the DC resistance R of the R head 12 will be described. The magnetic head 1 is held at an appropriate height above the surface of the disk 2, and the MR head 12 is separated by DC. Then, a bias current I is caused to flow by the constant current circuit 9 to cause a voltage drop, which is input to the two operational amplifiers 81a and 81b, and MR
The respective terminal voltages of the head 12 are detected, and these are output by the operational amplifier 82 in the subtracted absolute value, and the voltage drop E
Is output and input to the signal processing circuit 73. The bias current I is preset to a certain value by the constant current circuit 9, and the ratio E / I of the two is determined by the measured voltage drop E and
That is, the DC resistance R is calculated by the CPU 5. It is compared with the reference value R S set to this, and the quality is judged and inspected. According to the above procedure, each MR head 12
MR heads 12 which are automatically inspected sequentially and determined to be defective
Is discarded, and the electromagnetic conversion characteristics of the non-defective product are continuously measured and inspected.
【００１０】[0010]
【発明の効果】上記の説明のとおり、この発明の検査方
法においては、ＭＲヘッドの電磁変換特性に対するヘッ
ドテスターに、直流抵抗測定回路を付加し、電磁変換測
定機能を利用して直流抵抗を測定し、ＭＲヘッドを自動
検査するもので、従来の別個の測定器における磁気ヘッ
ドの着脱と測定の手間が省略され、ＭＲヘッドの直流抵
抗検査の効率化に寄与するところには、大きいものがあ
る。As described above, in the inspection method of the present invention, a DC resistance measuring circuit is added to the head tester for the electromagnetic conversion characteristics of the MR head, and the DC resistance is measured using the electromagnetic conversion measuring function. However, the MR head is automatically inspected, and the labor of attaching and detaching the magnetic head and the measurement in the conventional separate measuring device is omitted, and there is a great contribution to the efficiency of the DC resistance inspection of the MR head. .
【図１】図１は、この発明の直流抵抗検査方法を適用し
たヘッドテスターの構成図である。FIG. 1 is a configuration diagram of a head tester to which a DC resistance inspection method of the present invention is applied.
【図２】図２は、ＭＲヘッドを有する磁気ヘッドの概略
図である。FIG. 2 is a schematic diagram of a magnetic head having an MR head.
【図３】図３はヘッドテスターの概略の構成を示し、
(a) は磁気ヘッドと磁気ディスクの位置関係の説明図、
(b) は、ＭＲヘッドの電磁変換特性に対する測定回路の
構成図である。FIG. 3 shows a schematic configuration of a head tester,
(a) is an explanatory diagram of the positional relationship between the magnetic head and the magnetic disk,
(b) is a block diagram of a measuring circuit for the electromagnetic conversion characteristics of the MR head.
【図４】図４は、バイアス電流に対するＭＲヘッドの感
度特性の説明図で、(a) はバイアス電流に対する感度特
性曲線図、(b) はバイアス電流の供給方法の説明図であ
る。4A and 4B are explanatory diagrams of the sensitivity characteristic of the MR head with respect to a bias current, FIG. 4A is a sensitivity characteristic curve diagram with respect to the bias current, and FIG. 4B is an explanatory diagram of a bias current supply method.
１…磁気ヘッド、10…スライダー、11…コイルヘッド、
12…ＭＲヘッド、２…磁気ディスク、３…スピンドル、
４…キャリッジ機構、５…ＣＰＵ、６…書込み回路、７
…演算処理部、71…コンデンサ、72…差動アンプ、73…
信号処理回路、74…Ａ／Ｄ変換器、８…電圧降下検出回
路、81a,81b,82…オペアンプ、９…定電流源回路、Ｉ…
バイアス電流、Ｒ…ＭＲヘッドの直流抵抗、ＲS …直流
抵抗の基準値。1 ... magnetic head, 10 ... slider, 11 ... coil head,
12 ... MR head, 2 ... magnetic disk, 3 ... spindle,
4 ... Carriage mechanism, 5 ... CPU, 6 ... Writing circuit, 7
... arithmetic processing unit, 71 ... capacitor, 72 ... differential amplifier, 73 ...
Signal processing circuit, 74 ... A / D converter, 8 ... Voltage drop detection circuit, 81a, 81b, 82 ... Operational amplifier, 9 ... Constant current source circuit, I ...
Bias current, R ... MR head DC resistance, R S ... DC resistance reference value.
Claims (1)
抵抗ヘッドよりなる磁気ヘッドを検査対象とし、該コイ
ルヘッドにより磁気ディスクに書込まれたテストデータ
を、所定値のバイアス電流が供給された磁気抵抗ヘッド
により読出し、該読出し信号を信号処理回路により処理
して、該磁気抵抗ヘッドの電磁変換特性を測定し、この
測定データをＣＰＵにより処理して、該特性の良否を判
定して検査するヘッドテスターにおいて、 前記ヘッドテスターに対して、高入力インピーダンスを
有する電圧降下検出回路よりなる直流抵抗測定回路を付
加し、前記ヘッドテスターに磁気抵抗ヘッドを順次に装
着してバイアス電流を供給し、該電圧降下検出回路によ
り、該各磁気抵抗ヘッドの電圧降下を検出し、該検出信
号を前記信号処理回路により処理して、該各磁気抵抗ヘ
ッドの直流抵抗を順次に算出し、該各算出データを前記
ＣＰＵ入力して、これに設定された基準値にそれぞれ比
較し、該直流抵抗の良否を順次に判定することを特徴と
する、磁気抵抗ヘッドの直流抵抗検査方法。1. A magnetic head composed of a write coil head and a read magnetic resistance head is tested, and the test data written on a magnetic disk is supplied with a bias current of a predetermined value by the coil head. The magnetoresistive head is read, the read signal is processed by a signal processing circuit, the electromagnetic conversion characteristic of the magnetoresistive head is measured, and the measured data is processed by the CPU to judge whether the characteristic is good or not and inspect it. In the head tester, a DC resistance measurement circuit including a voltage drop detection circuit having a high input impedance is added to the head tester, and a magnetic resistance head is sequentially mounted on the head tester to supply a bias current, The voltage drop detection circuit detects the voltage drop of each of the magnetoresistive heads, and the detection signal is processed by the signal processing circuit. Then, the DC resistance of each of the magnetoresistive heads is sequentially calculated, and each calculated data is input to the CPU and compared with a reference value set therein, and the quality of the DC resistance is sequentially judged. A DC resistance inspection method for a magnetoresistive head, comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06215317A JP3101793B2 (en) | 1994-08-17 | 1994-08-17 | DC resistance inspection method for magnetoresistive head |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06215317A JP3101793B2 (en) | 1994-08-17 | 1994-08-17 | DC resistance inspection method for magnetoresistive head |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0855314A true JPH0855314A (en) | 1996-02-27 |
| JP3101793B2 JP3101793B2 (en) | 2000-10-23 |
Family
ID=16670316
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP06215317A Expired - Lifetime JP3101793B2 (en) | 1994-08-17 | 1994-08-17 | DC resistance inspection method for magnetoresistive head |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3101793B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0973154A1 (en) * | 1998-07-17 | 2000-01-19 | Koninklijke Philips Electronics N.V. | Automatic resistance measuring device |
| US6667613B1 (en) | 1999-12-20 | 2003-12-23 | Fujitsu Limited | Method of measuring resistance of magnetoresistive element |
| KR100440794B1 (en) * | 1997-05-23 | 2004-09-18 | 삼성전자주식회사 | Method for discerning damage of a magnetoresistive head by measuring resistance of a magnetoresistive sensor of the magnetoresistive head |
-
1994
- 1994-08-17 JP JP06215317A patent/JP3101793B2/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100440794B1 (en) * | 1997-05-23 | 2004-09-18 | 삼성전자주식회사 | Method for discerning damage of a magnetoresistive head by measuring resistance of a magnetoresistive sensor of the magnetoresistive head |
| EP0973154A1 (en) * | 1998-07-17 | 2000-01-19 | Koninklijke Philips Electronics N.V. | Automatic resistance measuring device |
| FR2781285A1 (en) * | 1998-07-17 | 2000-01-21 | Koninkl Philips Electronics Nv | AUTOMATIC RESISTANCE MEASURING DEVICE |
| US6667613B1 (en) | 1999-12-20 | 2003-12-23 | Fujitsu Limited | Method of measuring resistance of magnetoresistive element |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3101793B2 (en) | 2000-10-23 |
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