JP3101793B2 - DC resistance inspection method for magnetoresistive head - Google Patents
DC resistance inspection method for magnetoresistive headInfo
- Publication number
- JP3101793B2 JP3101793B2 JP06215317A JP21531794A JP3101793B2 JP 3101793 B2 JP3101793 B2 JP 3101793B2 JP 06215317 A JP06215317 A JP 06215317A JP 21531794 A JP21531794 A JP 21531794A JP 3101793 B2 JP3101793 B2 JP 3101793B2
- Authority
- JP
- Japan
- Prior art keywords
- head
- resistance
- magnetoresistive
- tester
- voltage drop
- 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.)
- Expired - Lifetime
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
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 direct current 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 reduced in size and weight by thinning, and more recently, an MR head is exclusively used for reading data.
However, a coil type thin film head is used for writing as in the conventional case. The MR head is formed by using permalloy as a material and utilizes the fact that the resistance value of permalloy changes according to the strength of the magnetic field. The MR head detects a change in the magnetic field of the disk and reads data. FIG. 2 shows the appearance of the magnetic head 1. The magnetic head 1 includes a slider 10, a coil head 11 for writing, an MR head 12 for reading, and the like, which are fixed to the positions shown in the grooves of the slider 10, respectively. 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 and 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 configuration of a head tester, and a method for testing both the impedance and the electromagnetic conversion characteristics of the MR head 12 will be described. 2A, the magnetic disk 2 is mounted on a spindle 3 and rotates. On the other hand, the magnetic head 1 to be inspected is mounted on a carriage mechanism 4 by a handling mechanism and moves in the radial direction of the disk 2. . (b) shows the configuration of the measurement unit, and the CPU 5
And a writing circuit 6 and an arithmetic processing unit 7. CPU5
A test signal is sent from the write circuit 6 to the coil head 11 in accordance with the command, and the test signal is sequentially written on the tracks of the disk 2 and read out by the MR head 12. 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. Electromagnetic conversion characteristics are determined, these data are digitized by the A / D converter 74, input to the CPU 5, and are compared with reference values for each of them to automatically inspect the quality.
【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-described MR head 12 operates by applying a DC bias current. Further, since the detection sensitivity to a magnetic field varies depending on the value of the bias current, it is necessary to optimize the detection sensitivity. It is necessary to provide an appropriate bias current. FIG. 4 shows an MR head
This explains the sensitivity characteristics to 12 bias currents.
(a), the horizontal axis represents the bias current I and the magnetic field strength m,
The vertical axis shows the sensitivity characteristic curves for both, and the steeper the curves, the higher the detection sensitivity. For example, when the bias current I is zero, the output current i 0 to changing magnetic field strength m is small, the bias current I S or -I S inclination corresponding to steep point p, 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 so as to supply an appropriate bias current I S to set the detection sensitivity 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 number of MR heads will now be described.
12 has variations in the respective DC resistances R due to the unevenness of the resistance of the permalloy, etc., which also causes variations in the bias current I due to the predetermined voltage E, and the detection sensitivity is not optimally set. There is. On the other hand, conventionally, a measuring instrument is separately provided to measure the DC resistance R of each MR head. If the DC resistance R is out of the allowable range of the reference value, it is discarded as defective. And tested for both characteristics. But,
When the DC resistance R is measured by a separate measuring device, it is necessary to attach and detach each magnetic head 1 to and from the measuring device and to perform the measurement. Therefore, a DC resistance measurement circuit is added to the above-described head tester to measure the DC resistance R of the MR head 12, and
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 the quality of both characteristics, if both functions are used for calculating the DC resistance R and judging the quality, it is convenient because no special means is required for these.
The present invention has been made in view of the above, and an object of the present invention is to provide an inspection method in which a DC resistance measurement circuit is added to a head tester, thereby automatically inspecting the DC resistance of the 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。According to the present invention, there is provided a method for inspecting a direct current resistance of an MR head, wherein a direct current 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 mounted on the head tester, a bias current is supplied, a voltage drop detection circuit detects a voltage drop of each MR head, a detected voltage is processed by a signal processing circuit, and a DC resistance of each MR head is measured. Are sequentially calculated, and the calculated data is C
PU input, and each is compared with a reference value set therein to sequentially determine the quality of the DC resistance.
【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 voltage drop of the MR head sequentially mounted on the head tester is detected by the voltage drop detection circuit added to the head tester. The detection signal is processed by a signal processing circuit,
The DC resistance of each MR head is sequentially calculated, and the data of the calculated DC resistance is input to a data processing unit, and is compared with a reference value set in the data processing unit to automatically determine pass / fail. The MR head determined to be defective is discarded, and a non-defective MR head is subsequently inspected by measuring both characteristics of impedance and electromagnetic conversion. In the above, since the input impedance of the voltage drop detection circuit is high, it does not affect the measurement of both the impedance and electromagnetic conversion characteristics of the MR head.
As described above, since the measurement and inspection of the DC resistance of the MR head are automated, the labor required for attaching and detaching the magnetic head and the measurement required in the case of the conventional separate measuring device are omitted, and the inspection is made more efficient. Is 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。FIG. 1 shows a configuration of a head tester to which the present invention is applied. The head tester has the same configuration as that of FIG. 3 described above, and the same components have the same numbers. In the present invention, a DC resistance measuring circuit is formed by adding a voltage drop detecting circuit 8 to a head tester, and a reference value RS of the DC resistance R is set in the CPU 5. The voltage drop detecting circuit 8 is composed of two operational amplifiers 81a and 81 having high input impedance, which are connected to both terminals of the MR head 12, respectively.
b and an operational amplifier 82 connected to these outputs for outputting a 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, M in the above-mentioned head tester will be described.
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 from the surface of the disk 2 and the MR head 12 is separated in a DC manner. Subsequently, 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,
The respective terminal voltages of the head 12 are detected, and these are output as a subtracted absolute value by the operational amplifier 82, and the voltage drop E
Is output and input to the signal processing circuit 73. The bias current I is previously set 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.
That is, the DC resistance R is calculated by the CPU 5. It is compared with a reference value R S set to this, and its quality is determined and inspected. By the above procedure, each MR head 12
Are automatically inspected sequentially and are determined to be defective.
Is discarded, and the non-defective product is continuously measured and inspected for its electromagnetic conversion characteristics.
【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 a head tester for the electromagnetic conversion characteristics of the MR head, and the DC resistance is measured using the electromagnetic conversion measuring function. However, there is a large one that automatically inspects the MR head, which eliminates the trouble of attaching and detaching the magnetic head and measuring in a conventional separate measuring device, and contributing 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 according to 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 configuration diagram of a measurement 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。FIGS. 4A and 4B are diagrams illustrating sensitivity characteristics of the MR head with respect to a bias current; FIG. 4A is a diagram illustrating a sensitivity characteristic curve with respect to a bias current, and FIG. 4B is a diagram illustrating a method of supplying a bias current;
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 section, 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: DC resistance of MR head, RS : Reference value of DC resistance.
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 comprising a coil head for writing and a magnetoresistive head for reading is tested, and a bias current of a predetermined value is supplied to test data written on a magnetic disk by the coil head. The read signal is read by a magnetoresistive head, the read signal is processed by a signal processing circuit, the electromagnetic conversion characteristics of the magnetoresistive head are measured, and the measured data is processed by a CPU to judge and inspect the quality of the characteristics. 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 bias current is supplied by sequentially mounting a magnetoresistive head on the head tester, A voltage drop detecting circuit detects a 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, the respective calculated data is input to the CPU, and each of the calculated data is compared with a reference value set in the CPU to sequentially determine the quality of the DC resistance. A method for inspecting a direct current resistance of a magnetoresistive head.
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 JPH0855314A (en) | 1996-02-27 |
| JP3101793B2 true 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) |
Families Citing this family (3)
| 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 |
| FR2781285A1 (en) * | 1998-07-17 | 2000-01-21 | Koninkl Philips Electronics Nv | AUTOMATIC RESISTANCE MEASURING DEVICE |
| JP3698940B2 (en) | 1999-12-20 | 2005-09-21 | 富士通株式会社 | Method for measuring resistance value of magnetoresistive effect element |
-
1994
- 1994-08-17 JP JP06215317A patent/JP3101793B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0855314A (en) | 1996-02-27 |
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