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JP2008203238A - Current detecting device - Google Patents

Current detecting device Download PDF

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JP2008203238A
JP2008203238A JP2007075551A JP2007075551A JP2008203238A JP 2008203238 A JP2008203238 A JP 2008203238A JP 2007075551 A JP2007075551 A JP 2007075551A JP 2007075551 A JP2007075551 A JP 2007075551A JP 2008203238 A JP2008203238 A JP 2008203238A
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current
measured
compensation
magnetic field
insulating layer
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JP4853807B2 (en
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Nobuyuki Shinchi
信幸 新地
Akira Okada
章 岡田
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Kohshin Electric Corp
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Kohshin Electric Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To solve the problems on a conventional current sensor having a thin film coil in which a measured current flows, installed opposite to and adjacent to magnetic resistance effect elements, for measuring a weak current flowing in an adjacent measured current wire, that it is of such a coil type that a conductor in which the measured current flows is constructed in the same plane, and so a turn-around portion for circulation and a portion, not opposed to the magnetic resistance effect elements in which the measured current flows in the opposite direction, are unnecessary for constructing the sensor and disadvantageous in reducing the size because of an increased surface area. <P>SOLUTION: This current detecting device includes the measured current wire consisting of measured conductor installed opposite to the magnetic resistance effect elements and a through-connecting current wire connecting these together for coiling the magnetic resistance effect elements outside the plane. Thus, the current detecting device has an effectively reduced size. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

この発明は、近接した被測定電流線に流れる微弱な電流を精度良く測定する小型の電流検知デバイスに関するものである。  The present invention relates to a small current detection device that accurately measures a weak current flowing in a current line to be measured.

従来の近接した被測定電流線に流れる微弱な電流を測定するものとしては、被測定電流が流れる薄膜コイルを磁気抵抗効果素子に対向し、かつ近接して設置した電流センサがある(例えば、特許文献1参照)。  As a conventional method for measuring a weak current flowing in a close current line to be measured, there is a current sensor in which a thin film coil in which a current to be measured flows is opposed to a magnetoresistive element and placed in close proximity (for example, a patent) Reference 1).

特開2006−153697公報  JP 2006-153697 A

微弱電流の測定には、上記特許文献1に開示されているように、被測定電流が流れる導体を各磁気抵抗効果素子に対向し、かつ近接して設置した測定が有効である。しかし被測定電流が流れる導体が同一面内に構成されたコイル型であるため、周回のための折り返し部分や被測定電流が逆方向に流れる磁気抵抗効果素子に対向しない部分はセンサを構成する上で不用な箇所であり、表面積が増大することで小型化には不利という問題点があった。
また、高精度化において、磁気抵抗効果素子に逆方向の磁界を付与するために2つの薄膜コイルを配置した例も示されるが、磁気抵抗効果素子に対向しない不用な箇所がさらに増えるだけでなく、被測定電流を付与するための取り出し電極も増えることになり、トータルでの表面積の増大が避けられず小型化には不利という問題点があった。
For the measurement of the weak current, as disclosed in Patent Document 1, it is effective to place a conductor through which a current to be measured is placed facing each magnetoresistive element and in close proximity. However, since the conductor through which the current to be measured flows is a coil type configured in the same plane, the folded portion for circulation and the portion not facing the magnetoresistive effect element through which the current to be measured flows in the reverse direction constitute the sensor. In addition, there is a problem that it is disadvantageous for downsizing because the surface area increases.
In addition, in order to improve accuracy, an example in which two thin-film coils are arranged to apply a magnetic field in the opposite direction to the magnetoresistive effect element is also shown, but not only the unnecessary portions that do not face the magnetoresistive effect element further increase. As a result, the number of extraction electrodes for applying the current to be measured is increased, and the total surface area is inevitably increased, which is disadvantageous for miniaturization.

この発明は上記のような課題を解決するためになされたもので、一様な外部磁界を除去して高精度化を図るとともに、微弱な電流の測定が可能な、小型かつ高精度である電流検知デバイスを得ることを目的とする。  The present invention has been made to solve the above-described problems, and is a small and highly accurate current capable of improving accuracy by removing a uniform external magnetic field and capable of measuring a weak current. The purpose is to obtain a sensing device.

この発明に係る電流検知デバイスは、設置基板上に構成された第1の絶縁層上に配置した4つの磁気抵抗効果素子で、第1のハーフブリッジ回路と第2のハーフブリッジ回路からブリッジ回路が構成され、かつ各磁気抵抗効果素子に対向して設置した被測定導体とそれらを接続する貫通接続電流線から、被測定電流を印加する被測定電流線を構成するようにしたものである。  The current detection device according to the present invention includes four magnetoresistive elements arranged on a first insulating layer formed on an installation substrate, and a bridge circuit is formed from the first half bridge circuit and the second half bridge circuit. A current line to be measured for applying a current to be measured is constituted by a conductor to be measured which is configured and installed facing each magnetoresistive element and a through-connection current line connecting them.

以上のように、この発明によれば、設置基板上に構成された第1の絶縁層上に配置した4つの磁気抵抗効果素子で、第1のハーフブリッジ回路と第2のハーフブリッジ回路からブリッジ回路が構成され、それぞれのハーフブリッジ回路に被測定電流に起因して逆方向の磁界が付与される構造のため、一様な外部磁界が除去され高精度化が実現できるとともに、各磁気抵抗効果素子に対向して設置した被測定導体とそれらを接続する貫通接続電流線から成る被測定電流線が磁気抵抗効果素子を面外で巻回するような構造にしたため、電流検知デバイスが小型となる効果がある。  As described above, according to the present invention, the four magnetoresistive elements arranged on the first insulating layer formed on the installation substrate are bridged from the first half-bridge circuit and the second half-bridge circuit. Since the circuit is configured and a magnetic field in the reverse direction is applied to each half-bridge circuit due to the current to be measured, uniform external magnetic fields can be removed to achieve high accuracy, and each magnetoresistive effect The current sensing device is made compact because the current wire to be measured, which consists of the conductor to be measured placed opposite to the element and the through-connection current line connecting them, winds the magnetoresistive element out of the plane. effective.

実施の形態1.
図1は、この発明の実施の形態1による電流検知デバイス20の一部の斜視模式図を示すもので、図2は図1におけるAA断面(XZ面)を示す断面図、図3は図2の拡大断面図、図4は被測定電流検出部14の平面図(XY面)である。図において、磁気検知デバイス20は、4つの磁気抵抗効果素子1によるブリッジ回路18にて構成された被測定電流検出部14と被測定電流線6により構成される。
まず、被測定電流検出部14の構成について説明する。
図4は被測定電流検出部14の平面図を示すもので、中心線15によって2つの領域に分けられ、それぞれの領域に磁気抵抗効果素子1a、1b、磁気抵抗効果素子1c、1dが線対称に等しく配置される。4つの磁気抵抗効果素子1a〜1dは、設置基板7の中心線15に対して相互に平行方向に配置され、磁気抵抗効果素子1a、1dは、互いに逆方向の磁界の増加に応じて抵抗値が共に増加する磁気抵抗効果特性を有するように、また、磁気抵抗効果素子1b、1cは、互いに逆方向の磁界の増加に応じて抵抗値が共に減少する磁気抵抗効果特性を有するように、図には省略したが、磁気抵抗効果素子上にはバーバーポール電極構造が形成されている。なお、4つの磁気抵抗効果素子1はそれぞれ1本で構成したが、クランク形状に複数の磁気抵抗効果素子を接続し、線路長を長く構成してもよい。また、4つの磁気抵抗効果素子1は中心線15上の中心点に対して点対称に構成してもよい。接続電流線2は、4つの磁気抵抗効果素子1間を接続することにより、ブリッジ回路18を構成するものであり、接続エリア16は、外部とブリッジ回路18の入出力端子として用いる。
Embodiment 1 FIG.
FIG. 1 is a schematic perspective view of a part of the current detection device 20 according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view showing a cross section AA (XZ plane) in FIG. 1, and FIG. FIG. 4 is a plan view (XY plane) of the measured current detector 14. In the figure, the magnetic sensing device 20 includes a measured current detector 14 and a measured current line 6 that are configured by a bridge circuit 18 including four magnetoresistive elements 1.
First, the configuration of the measured current detection unit 14 will be described.
FIG. 4 is a plan view of the measured current detection unit 14, which is divided into two regions by a center line 15. In each region, the magnetoresistive effect elements 1 a and 1 b and the magnetoresistive effect elements 1 c and 1 d are line symmetric. Are arranged equally. The four magnetoresistive effect elements 1a to 1d are arranged in parallel to each other with respect to the center line 15 of the installation substrate 7, and the magnetoresistive effect elements 1a and 1d have a resistance value according to an increase in the magnetic field in the opposite direction. The magnetoresistive effect elements 1b and 1c have a magnetoresistive effect characteristic in which both resistance values decrease as the magnetic field increases in the opposite direction. Although not shown, a barber pole electrode structure is formed on the magnetoresistive element. Although the four magnetoresistive effect elements 1 are each constituted by one piece, a plurality of magnetoresistive effect elements may be connected in a crank shape to make the line length longer. The four magnetoresistive elements 1 may be configured to be point-symmetric with respect to the center point on the center line 15. The connection current line 2 forms a bridge circuit 18 by connecting the four magnetoresistive effect elements 1, and the connection area 16 is used as an input / output terminal of the bridge circuit 18 with the outside.

図5はこの発明の実施の形態1による電流検知デバイス20の被測定電流検出部14を示す構成概略図であり、図5において、4つの磁気抵抗効果素子1間を接続電流線2で接続することにより、磁気抵抗効果素子1a、1bの直列接続からなるハーフブリッジ回路(第1のハーフブリッジ回路)17a、磁気抵抗効果素子1c、1dの直列接続からなるハーフブリッジ回路(第2のハーフブリッジ回路)17bの並列接続からなるブリッジ回路18を構成するものである。
接続エリア(第1の接続エリア)16aは、ブリッジ回路18の磁気抵抗効果素子1a、1c間の接続電流線2に接続され、接続エリア(第2の接続エリア)16bは、ブリッジ回路18の磁気抵抗効果素子1b、1d間の接続電流線2に接続され、接続エリア16a、16bからブリッジ回路18に電圧が供給されるものである。接続エリア(第3の接続エリア)16cは、ブリッジ回路18の磁気抵抗効果素子1a、1b間の接続電流線2に接続され、接続エリア(第4の接続エリア)16dは、ブリッジ回路18の磁気抵抗効果素子1c、1d間の接続電流線2に接続され、接続エリア16c、16dからブリッジ回路18の出力電圧が検出されるものである。
FIG. 5 is a schematic configuration diagram showing a measured current detector 14 of the current detection device 20 according to the first embodiment of the present invention. In FIG. 5, four magnetoresistive elements 1 are connected by a connection current line 2. Thus, a half bridge circuit (first half bridge circuit) 17a composed of series connection of magnetoresistive effect elements 1a and 1b, and a half bridge circuit (second half bridge circuit composed of series connection of magnetoresistive effect elements 1c and 1d). ) Constitutes a bridge circuit 18 consisting of 17b in parallel connection.
The connection area (first connection area) 16 a is connected to the connection current line 2 between the magnetoresistive effect elements 1 a and 1 c of the bridge circuit 18, and the connection area (second connection area) 16 b is the magnetic field of the bridge circuit 18. It is connected to the connection current line 2 between the resistance effect elements 1b and 1d, and a voltage is supplied to the bridge circuit 18 from the connection areas 16a and 16b. The connection area (third connection area) 16 c is connected to the connection current line 2 between the magnetoresistive effect elements 1 a and 1 b of the bridge circuit 18, and the connection area (fourth connection area) 16 d is the magnetic field of the bridge circuit 18. It is connected to the connection current line 2 between the resistance effect elements 1c and 1d, and the output voltage of the bridge circuit 18 is detected from the connection areas 16c and 16d.

なお、図4には省略したが、設置基板7上の4つの磁気抵抗効果素子1a〜1dは、絶縁層および被測定導体を介して設置基板7上に設置される。また、4つの磁気抵抗効果素子1a〜1dは、被測定電流線より付与される磁界の方向により、中心線15によって2つの領域に分けて設置するものとしたが、これはできるだけ被測定電流線の引き回しを簡略化するためであり、4つの磁気抵抗効果素子1a〜1dの設置構成は、これに限るものではない。  Although omitted in FIG. 4, the four magnetoresistive elements 1 a to 1 d on the installation substrate 7 are installed on the installation substrate 7 through the insulating layer and the conductor to be measured. The four magnetoresistive effect elements 1a to 1d are divided into two regions by the center line 15 depending on the direction of the magnetic field applied from the measured current line. The installation configuration of the four magnetoresistive effect elements 1a to 1d is not limited to this.

次に、電流検知デバイス20の構成について説明する。
被測定電流を印加する被測定電流線6は、図1に示されるように第1の被測定導体3(1点鎖線)、第2の被測定導体4(2点鎖線)、および貫通接続電流線5(実線)により1本に接続され、第1の被測定導体3、第2の被測定導体4はそれぞれ絶縁層8、および9を介して磁気抵抗効果素子1の上方および下方に設置される。さらに第1の被測定導体3、第2の被測定導体4は磁気抵抗効果素子1で構成される被測定電流検出部14を面外で巻回するように貫通接続電流線5にて接続されており、図2において第1の被測定導体3の電流印加方向が紙面に垂直な手前方向であれば、第2の被測定導体4の電流印加方向は紙面に垂直な奥行き方向となっている。被測定電流値が特に微弱であれば、磁気抵抗効果素子1に効果的に被測定電流による磁界を付与するために、可能な限り磁気抵抗効果素子1に接近して第1の被測定導体3、および第2の被測定導体4を設置するのが望ましいが、電気的に絶縁され耐圧を確保する必要がある。第1、第2の被測定導体3、4、貫通接続電流線5には、例えば低抵抗材料であるアルミニウムや金などが選択され、絶縁層としては、例えばシリコン窒化膜やシリコン酸化膜、あるいはポリイミドなどの樹脂材料が選択される。それぞれ耐電圧等の異なる仕様を有するため、印加される被測定電流値や予期されるサージ電圧等の非定常な場合も踏まえて選択する必要がある。また、磁気抵抗効果素子1は、例えば半導体微細加工技術により作製されるものであり、強磁性体のニッケル、鉄等を主成分とする薄膜があるがこれに限定されるものではない。設置基板7は、後工程で作製される磁気抵抗効果素子1や絶縁層などを均一、かつ緻密に設置するためにフラットな面を有するものがよく、一般的にはシリコン基板(シリコンウエハ)やガラス基板が使用される。各絶縁層および保護層11はすべて同一の素材でなく、複数の素材を使い分けてもよい。また、絶縁性、耐圧の効果を上げるために積層化してもよい。保護層11は、電流検知デバイス20の内部構造の劣化を防ぐために、外部からの湿気や酸化剤、腐食剤等の侵入を遮断するものである。電流検知デバイス20の内部構造は、例えば半導体微細加工技術により一貫して作製されるのが望ましく、各層の作製には、スパッタリング、CVD等の技術が利用される。これらの技術によれば、非常に寸法精度が高く、小型な電流検知デバイス20が作製できる。
Next, the configuration of the current detection device 20 will be described.
As shown in FIG. 1, the measured current line 6 to which the measured current is applied includes a first measured conductor 3 (one-dot chain line), a second measured conductor 4 (two-dot chain line), and a through connection current. The first measured conductor 3 and the second measured conductor 4 are connected above and below the magnetoresistive effect element 1 through insulating layers 8 and 9, respectively, connected by a line 5 (solid line). The Further, the first measured conductor 3 and the second measured conductor 4 are connected by the through-connection current line 5 so as to wind the measured current detection unit 14 composed of the magnetoresistive effect element 1 out of the plane. In FIG. 2, if the current application direction of the first measured conductor 3 is the front direction perpendicular to the paper surface, the current application direction of the second measured conductor 4 is the depth direction perpendicular to the paper surface. . If the measured current value is particularly weak, the first measured conductor 3 is as close to the magnetoresistive effect element 1 as possible in order to effectively give the magnetoresistive effect element 1 a magnetic field due to the measured current. It is desirable to install the second conductor 4 to be measured, but it is necessary to be electrically insulated to ensure a withstand voltage. For the first and second measured conductors 3 and 4 and the through-connection current line 5, for example, a low-resistance material such as aluminum or gold is selected, and as the insulating layer, for example, a silicon nitride film, a silicon oxide film, or A resin material such as polyimide is selected. Since each has different specifications such as withstand voltage, it is necessary to select based on non-stationary cases such as an applied measured current value and an expected surge voltage. The magnetoresistive effect element 1 is manufactured by, for example, a semiconductor microfabrication technique, and includes a thin film mainly composed of a ferromagnetic material such as nickel or iron, but is not limited thereto. The installation substrate 7 preferably has a flat surface in order to uniformly and densely install the magnetoresistive effect element 1 and the insulating layer produced in a later process, and is generally a silicon substrate (silicon wafer) or A glass substrate is used. Each insulating layer and protective layer 11 are not all the same material, and a plurality of materials may be used properly. Further, in order to increase the effect of insulation and breakdown voltage, lamination may be performed. The protective layer 11 blocks entry of moisture, an oxidizing agent, a corrosive agent, and the like from the outside in order to prevent deterioration of the internal structure of the current detection device 20. The internal structure of the current detection device 20 is desirably manufactured consistently by, for example, a semiconductor microfabrication technique, and techniques such as sputtering and CVD are used for manufacturing each layer. According to these techniques, the dimensional accuracy is very high, and the small current detection device 20 can be manufactured.

次に、電流検知デバイス20の動作について説明する。
被測定電流線6に電流を印加すると、第1の被測定導体3、第2の被測定導体4には、図3の破線に示す印加磁界方向13a、13bのように互いに逆方向の電流に対して左または右回転の磁界がその電流の大きさに応じて発生するので、第1の被測定導体3、第2の被測定導体4に、上下方向に挟まれて位置する磁気抵抗効果素子1には、同一方向に合成された印加磁界が付与され、その方向は、測定磁界方向12(破線矢印)となる。被測定電流検出部14には、例えば図4において磁気抵抗効果素子1a、1bには、中心線15より紙面左側の向きに磁界が加わり、また、磁気抵抗効果素子1c、1dには、中心線15より紙面右側の向きに磁界が加わるように被測定電流線6を巻回する。
磁気抵抗効果素子1a、1dでは、共に磁界の増加に応じて抵抗値が増加すると共に、磁界の減少に応じて抵抗値が減少する磁気抵抗効果特性を有するように、また、磁気抵抗効果素子1b、1cでは、逆に磁界の増加に応じて抵抗値が減少すると共に、磁界の減少に応じて抵抗値が増加する磁気抵抗効果特性を有するように構成されている。
よって、被測定電流線6に流れる電流の増加に応じて磁気抵抗効果素子1a、1dの抵抗値が増加すると共に、磁気抵抗効果素子1b、1cの抵抗値が減少し、被測定電流線6に流れる電流の減少に応じて磁気抵抗効果素子1a、1dの抵抗値が減少すると共に、磁気抵抗効果素子1b、1cの抵抗値が増加する。このように、被測定電流線6に流れる電流の大きさに応じてブリッジ回路18の平衡が崩れ、これが電流検知デバイス20のブリッジ回路18の出力となる。
Next, the operation of the current detection device 20 will be described.
When a current is applied to the current line 6 to be measured, currents in opposite directions are applied to the first measured conductor 3 and the second measured conductor 4 as indicated by the applied magnetic field directions 13a and 13b shown in broken lines in FIG. On the other hand, a left or right rotating magnetic field is generated in accordance with the magnitude of the current, so that the magnetoresistive effect element is sandwiched between the first measured conductor 3 and the second measured conductor 4 in the vertical direction. 1, an applied magnetic field combined in the same direction is applied, and the direction is a measurement magnetic field direction 12 (broken arrow). For example, in FIG. 4, a magnetic field is applied to the measured current detector 14 in the direction of the left side of the center line 15 with respect to the magnetoresistive effect elements 1 a and 1 b, and the center line is applied to the magnetoresistive effect elements 1 c and 1 d. The current wire 6 to be measured is wound so that a magnetic field is applied in the direction of the right side of the drawing with respect to 15.
The magnetoresistive effect elements 1a and 1d both have a magnetoresistive effect characteristic in which the resistance value increases as the magnetic field increases and the resistance value decreases as the magnetic field decreases. On the other hand, 1c is configured to have a magnetoresistance effect characteristic in which the resistance value decreases as the magnetic field increases and the resistance value increases as the magnetic field decreases.
Therefore, the resistance values of the magnetoresistive effect elements 1a and 1d increase in accordance with the increase in the current flowing through the measured current line 6, and the resistance values of the magnetoresistive effect elements 1b and 1c decrease. As the flowing current decreases, the resistance values of the magnetoresistive effect elements 1a and 1d decrease and the resistance values of the magnetoresistive effect elements 1b and 1c increase. Thus, the balance of the bridge circuit 18 is lost in accordance with the magnitude of the current flowing through the current line 6 to be measured, and this becomes the output of the bridge circuit 18 of the current detection device 20.

次に、電流検知デバイス20を電流センサ22としての構成例(模式図)について、図6を用いて説明する。
センサ基板19上には、電流検知デバイス20とともにセンサ回路部21を配置する。センサ回路部21は、電流検知デバイス20の接続エリア16a、16bにブリッジ回路18の電圧を供給すると共に、ブリッジ回路18の接続エリア16c、16dから得る出力電圧を適度な増幅を施して出力するが、電流センサ外部への入出力には外部端子23を利用する。また、被測定電流の入出力には、電流検知デバイス20に設置された被測定電流線6に接続する電流端子24を利用する。
センサケース25は、センサ基板19、電流検知デバイス20、センサ回路部21を覆うものであり、内部構造の劣化を防ぐために、外部からの湿気や酸化剤、腐食剤等の侵入を遮断するものである。センサケース25は、特に材料を限定しないが非磁性で、経時劣化の少ないもの(例えばエンジニアリングプラスチック)が望ましい。
電流センサとしての動作としては、被測定電流線6に流れる電流の大きさに応じて生じるブリッジ回路18の平衡の崩れに起因し、センサ回路部21から適度な増幅を施して出力される出力電圧の大きさにより、被測定電流線6に流れる電流の大きさ、または被測定電流線6に流れる電流の大きさに相関のある値として検出することができる。
なお、被測定電流線6以外において発生された磁界(外乱磁界)は、磁気抵抗効果素子1a、1bと磁気抵抗効果素子1c、1d(ブリッジ回路の左右の各ハーフブリッジ回路)に同相の影響となるため、相殺され、測定精度に影響を与えない。
Next, a configuration example (schematic diagram) in which the current detection device 20 is the current sensor 22 will be described with reference to FIG.
On the sensor substrate 19, the sensor circuit unit 21 is arranged together with the current detection device 20. The sensor circuit unit 21 supplies the voltage of the bridge circuit 18 to the connection areas 16a and 16b of the current detection device 20, and outputs the output voltage obtained from the connection areas 16c and 16d of the bridge circuit 18 with appropriate amplification. The external terminal 23 is used for input / output to / from the current sensor. Further, a current terminal 24 connected to the measured current line 6 installed in the current detection device 20 is used for input / output of the measured current.
The sensor case 25 covers the sensor substrate 19, the current detection device 20, and the sensor circuit unit 21, and blocks intrusion of moisture, oxidant, corrosive agent, etc. from the outside in order to prevent deterioration of the internal structure. is there. The sensor case 25 is not particularly limited in material, but is preferably non-magnetic and has little deterioration with time (for example, engineering plastic).
As an operation as a current sensor, an output voltage that is output from the sensor circuit unit 21 after appropriate amplification is caused by a loss of balance of the bridge circuit 18 that occurs according to the magnitude of the current flowing through the current line 6 to be measured. Can be detected as a value having a correlation with the magnitude of the current flowing through the measured current line 6 or the magnitude of the current flowing through the measured current line 6.
It should be noted that the magnetic field (disturbance magnetic field) generated outside the current line 6 to be measured has the same effect on the magnetoresistive effect elements 1a and 1b and the magnetoresistive effect elements 1c and 1d (the left and right half bridge circuits of the bridge circuit). Therefore, it is offset and does not affect the measurement accuracy.

以上のように、この実施の形態1によれば、設置基板7上に構成された第1の絶縁層8上に配置した4つの磁気抵抗効果素子1で、第1のハーフブリッジ回路17aと第2のハーフブリッジ回路17bからブリッジ回路18が構成され、それぞれのハーフブリッジ回路に被測定電流に起因する逆方向の磁界が付与される構造としているため、一様な外部磁界が除去される効果がある。  As described above, according to the first embodiment, the first half-bridge circuit 17a and the first half-bridge circuit 17a are arranged with the four magnetoresistive elements 1 arranged on the first insulating layer 8 formed on the installation substrate 7. Since the bridge circuit 18 is configured from the two half-bridge circuits 17b and a magnetic field in the opposite direction due to the current to be measured is applied to each half-bridge circuit, the effect of removing a uniform external magnetic field is obtained. is there.

また、各磁気抵抗効果素子1に対向して設置した第1、および第2の被測定導体3、4とそれらを接続する貫通接続電流線5から成る被測定電流線6が磁気抵抗効果素子1を面外で巻回するような構造にしたため、電流検知デバイス20が小型となる効果がある。  In addition, the current-under-measurement line 6 including the first and second conductors 3 and 4 to be measured facing each magnetoresistive element 1 and the through-connection current line 5 connecting them is a magnetoresistive element 1. Since the structure is such that the coil is wound out of the plane, there is an effect that the current detection device 20 is reduced in size.

実施の形態2.
図7は、この発明の実施の形態2による電流検知デバイス20の1部の斜視模式図を示すもので、図8は図7におけるAA断面(XZ面)を示す断面図、図9は図8の拡大断面図である。図において、電流検知デバイス20は、4つの磁気抵抗効果素子1によるブリッジ回路18にて構成される被測定電流検出部14、被測定電流線6、補償電流線28により構成される。実施の形態2は、実施の形態1に補償電流線28を付加した構成であり、その他の構成で重複する部分は省略する。実施の形態2は、ブリッジ回路18の出力電圧に基づいて、被測定電流線6に流れる電流に起因して4つの磁気抵抗効果素子1の近傍に発生している磁界を打ち消すような電流(制御電流)を、センサ回路部21から付加した補償電流線28に供給するものである。
Embodiment 2. FIG.
7 is a schematic perspective view of a part of the current detection device 20 according to the second embodiment of the present invention. FIG. 8 is a cross-sectional view showing a cross section AA (XZ plane) in FIG. 7, and FIG. FIG. In the figure, the current detection device 20 is composed of a measured current detector 14, a measured current line 6, and a compensation current line 28 that are configured by a bridge circuit 18 including four magnetoresistive elements 1. The second embodiment has a configuration in which the compensation current line 28 is added to the first embodiment, and the redundant portions in other configurations are omitted. In the second embodiment, based on the output voltage of the bridge circuit 18, a current (control that cancels out the magnetic fields generated in the vicinity of the four magnetoresistive effect elements 1 due to the current flowing through the measured current line 6 is controlled. Current) is supplied from the sensor circuit section 21 to the compensation current line 28 added.

この発明の実施の形態2による電流検知デバイス20の構成について説明する。
補償電流を印加する補償電流線28は、図7に示されるように第1の補償電流導体26(太実線)、および接続補償電流線27(細実線)により1本に接続され、第1の補償電流導体26は、第1の被測定導体3、絶縁層9および29を介して磁気抵抗効果素子1の上方に設置される。本実施の形態2では、第1の補償電流導体26を磁気抵抗効果素子1の上方に設置する例を示したが、下方であってもよい。さらに第1の補償電流導体26は、磁気抵抗効果素子1で構成される被測定電流検出部14の構成面(XY面)に略平行な面で、ミアンダライン状に折り返すように接続補償電流線27にて接続されており、図7において第1の被測定導体3の電流印加方向が紙面に垂直な手前方向であれば、第1の補償電流導体26の補償電流印加方向は紙面に垂直な奥行き方向となる。磁気抵抗効果素子1に効果的に補償電流による磁界を付与するために、可能な限り磁気抵抗効果素子1に接近して第1の補償電流導体26を設置するのが望ましいが、電気的に絶縁され耐圧を確保する必要がある。第1の補償電流導体26、接続補償電流線27には、例えば低抵抗材料であるアルミニウムや金などが選択され、絶縁層としては、例えばシリコン窒化膜やシリコン酸化膜、あるいはポリイミドなどの樹脂材料が選択される。電流検知デバイス20の内部構造は、例えば半導体微細加工技術により一貫して作製されるのが望ましく、各層の作製には、スパッタリング、CVD等の技術が利用される。これらの技術によれば、非常に寸法精度が高く、小型な電流検知デバイス20が作製できる。
A configuration of the current detection device 20 according to the second embodiment of the present invention will be described.
As shown in FIG. 7, the compensation current line 28 for applying the compensation current is connected to one line by a first compensation current conductor 26 (thick solid line) and a connection compensation current line 27 (thin solid line). The compensation current conductor 26 is installed above the magnetoresistive effect element 1 through the first measured conductor 3 and the insulating layers 9 and 29. In the second embodiment, the example in which the first compensation current conductor 26 is installed above the magnetoresistive effect element 1 is shown, but it may be below. Further, the first compensation current conductor 26 is a surface that is substantially parallel to the configuration surface (XY plane) of the current-under-measurement detecting unit 14 configured by the magnetoresistive effect element 1, and is a connection compensation current line that is folded back in a meander line shape. 27, if the current application direction of the first measured conductor 3 in FIG. 7 is the front direction perpendicular to the paper surface, the compensation current application direction of the first compensation current conductor 26 is perpendicular to the paper surface. Depth direction. In order to effectively apply a magnetic field by a compensation current to the magnetoresistive effect element 1, it is desirable to place the first compensation current conductor 26 as close to the magnetoresistive effect element 1 as possible, but it is electrically insulated. It is necessary to ensure the withstand voltage. For the first compensation current conductor 26 and the connection compensation current line 27, for example, aluminum or gold which is a low resistance material is selected, and as the insulating layer, for example, a silicon nitride film, a silicon oxide film, or a resin material such as polyimide Is selected. The internal structure of the current detection device 20 is desirably manufactured consistently by, for example, a semiconductor microfabrication technique, and techniques such as sputtering and CVD are used for manufacturing each layer. According to these techniques, the dimensional accuracy is very high, and the small current detection device 20 can be manufactured.

次に、電流検知デバイス20の動作について説明する。
被測定電流線6に電流を印加すると、第1の被測定導体3、第2の被測定導体4の近傍には、図9の破線に示す印加磁界方向13a、13bのように互いに逆方向の電流に対して左または右回転の磁界がその電流の大きさに応じて発生するので、第1の被測定導体3、第2の被測定導体4に、上下方向に挟まれて位置する磁気抵抗効果素子1には、合成された同一方向の印加磁界が付与され、その方向は、測定磁界方向12(破線矢印)となる。被測定電流検出部14には、例えば図4において磁気抵抗効果素子1a、1bには、中心線15より紙面左側の向きに磁界が加わり、また、磁気抵抗効果素子1c、1dには、中心線15より紙面右側の向きに磁界が加わるように被測定電流線6を巻回する。
磁気抵抗効果素子1a、1dでは、共に磁界の増加に応じて抵抗値が増加すると共に、磁界の減少に応じて抵抗値が減少する磁気抵抗効果特性を有するように、また、磁気抵抗効果素子1b、1cでは、逆に磁界の増加に応じて抵抗値が減少すると共に、磁界の減少に応じて抵抗値が増加する磁気抵抗効果特性を有するように構成されている。
よって、被測定電流線6に流れる電流の増加に応じて磁気抵抗効果素子1a、1dの抵抗値が増加すると共に、磁気抵抗効果素子1b、1cの抵抗値が減少し、被測定電流線6に流れる電流の減少に応じて磁気抵抗効果素子1a、1dの抵抗値が減少すると共に、磁気抵抗効果素子1b、1cの抵抗値が増加する。
Next, the operation of the current detection device 20 will be described.
When a current is applied to the current line 6 to be measured, the first measured conductor 3 and the second measured conductor 4 are arranged in the directions opposite to each other as indicated by the applied magnetic field directions 13a and 13b shown by broken lines in FIG. Since a magnetic field that rotates left or right with respect to the current is generated according to the magnitude of the current, the magnetoresistor is sandwiched between the first measured conductor 3 and the second measured conductor 4 in the vertical direction. A combined applied magnetic field in the same direction is applied to the effect element 1, and the direction is a measurement magnetic field direction 12 (broken arrow). For example, in FIG. 4, a magnetic field is applied to the measured current detector 14 in the direction of the left side of the center line 15 with respect to the magnetoresistive effect elements 1 a and 1 b, and the center line is applied to the magnetoresistive effect elements 1 c and 1 d. The current wire 6 to be measured is wound so that a magnetic field is applied in the direction of the right side of the drawing with respect to 15.
The magnetoresistive effect elements 1a and 1d both have a magnetoresistive effect characteristic in which the resistance value increases as the magnetic field increases and the resistance value decreases as the magnetic field decreases. On the other hand, 1c is configured to have a magnetoresistance effect characteristic in which the resistance value decreases as the magnetic field increases and the resistance value increases as the magnetic field decreases.
Therefore, the resistance values of the magnetoresistive effect elements 1a and 1d increase in accordance with the increase in the current flowing through the measured current line 6, and the resistance values of the magnetoresistive effect elements 1b and 1c decrease. As the flowing current decreases, the resistance values of the magnetoresistive effect elements 1a and 1d decrease and the resistance values of the magnetoresistive effect elements 1b and 1c increase.

補償電流線28を配置した電流検知デバイス20とセンサ回路部21の概略構成を図10に示す。被測定電流線6に流れる電流の大きさに応じてブリッジ回路18の平衡が崩れる。このとき、センサ回路部21に設置された増幅回路部(例えばオペアンプ31)では、被測定電流検出部14の接続エリア16c、16dから検出される出力電圧に基づいて、磁気抵抗効果素子1a〜1d近傍に発生する磁界を打ち消すような電流(制御電流)を補償電流線28に供給する。具体的には接続エリア16c、16dの出力電圧が0になるように、制御電流の大きさを調整する。補償電流線28は、その制御電流の大きさに応じて4つの磁気抵抗効果素子1a〜1d近傍に発生する磁界、すなわち被測定電流線6に流れる電流の大きさに応じた磁界を相殺するような磁界を印加磁界方向13cに発生し、磁気抵抗効果素子1においては補償磁界方向30(1点鎖線矢印)となる。
したがって、被測定電流線6に流れる電流の大きさに応じたブリッジ回路18の平衡の崩れを、センサ回路部21から供給される制御電流により修復するこ
とができる。
ゆえに、センサ回路部21から供給した制御電流の大きさにより、被測定電流線6に流れる電流の大きさ、または被測定電流線6に流れる電流の大きさに相関のある値として検出することができる。
なお、被測定電流線6以外において発生された磁界(外乱磁界)は、磁気抵抗効果素子1a、1bと磁気抵抗効果素子1c、1d(ブリッジ回路の左右の各ハーフブリッジ回路)に同相の影響となるため、相殺され、測定精度に影響を与えない。
FIG. 10 shows a schematic configuration of the current detection device 20 and the sensor circuit unit 21 in which the compensation current line 28 is arranged. The balance of the bridge circuit 18 is lost depending on the magnitude of the current flowing through the current line 6 to be measured. At this time, in the amplifier circuit unit (for example, the operational amplifier 31) installed in the sensor circuit unit 21, the magnetoresistive effect elements 1a to 1d are based on the output voltages detected from the connection areas 16c and 16d of the measured current detection unit 14. A current (control current) that cancels the magnetic field generated in the vicinity is supplied to the compensation current line 28. Specifically, the magnitude of the control current is adjusted so that the output voltage of the connection areas 16c and 16d becomes zero. The compensation current line 28 cancels out the magnetic field generated in the vicinity of the four magnetoresistive elements 1a to 1d according to the magnitude of the control current, that is, the magnetic field according to the magnitude of the current flowing through the current line 6 to be measured. A strong magnetic field is generated in the applied magnetic field direction 13c, and in the magnetoresistive effect element 1, the compensation magnetic field direction 30 (one-dot chain line arrow) is obtained.
Therefore, the loss of balance of the bridge circuit 18 according to the magnitude of the current flowing through the current line 6 to be measured can be repaired by the control current supplied from the sensor circuit unit 21.
Therefore, the magnitude of the control current supplied from the sensor circuit unit 21 can be detected as a value correlated with the magnitude of the current flowing through the measured current line 6 or the magnitude of the current flowing through the measured current line 6. it can.
It should be noted that the magnetic field (disturbance magnetic field) generated outside the current line 6 to be measured has the same effect on the magnetoresistive effect elements 1a and 1b and the magnetoresistive effect elements 1c and 1d (the left and right half bridge circuits of the bridge circuit). Therefore, it is offset and does not affect the measurement accuracy.

以上のように、この実施の形態2によれば、ブリッジ回路18の出力電圧に基づき、被測定電流線6に流れる電流に起因して4つの磁気抵抗効果素子1の近傍に発生した磁界を打ち消すような電流を、センサ回路部21から付加した補償電流線28に供給する構成としたので、磁気抵抗効果素子1等の温度特性に起因した誤差が低減できるなどの効果が見込め、高精度化が可能となる。  As described above, according to the second embodiment, based on the output voltage of the bridge circuit 18, the magnetic fields generated in the vicinity of the four magnetoresistive effect elements 1 due to the current flowing through the measured current line 6 are canceled out. Since such a current is supplied to the compensation current line 28 added from the sensor circuit unit 21, it is possible to reduce the error due to the temperature characteristics of the magnetoresistive effect element 1 and the like, and the accuracy can be improved. It becomes possible.

実施の形態3.
図11は、この発明の実施の形態3による電流検知デバイス20の一部の斜視模式図を示すもので、図12は図11におけるAA断面(XZ面)を示す断面図、図13は図12の拡大断面図である。図において、電流検知デバイス20は、4つの磁気抵抗効果素子1によるブリッジ回路18にて構成される被測定電流検出部14、被測定電流線6(図11では省略)、補償電流線28により構成される。実施の形態3は、実施の形態2に第2の補償電流導体32を付加した構成であり、その他の構成で重複する部分は省略する。実施の形態3は、ブリッジ回路18の出力電圧に基づいて、被測定電流線6に流れる電流に起因して4つの磁気抵抗効果素子1の近傍に発生している磁界を打ち消すような電流を、センサ回路部21から補償電流線28に供給し、磁気抵抗効果素子1の上下方向から合成した補償磁界を印加するものである。
Embodiment 3 FIG.
11 is a schematic perspective view of a part of the current detection device 20 according to the third embodiment of the present invention. FIG. 12 is a cross-sectional view showing the AA cross section (XZ plane) in FIG. 11, and FIG. FIG. In the figure, the current detection device 20 includes a measured current detection unit 14 configured by a bridge circuit 18 including four magnetoresistive elements 1, a measured current line 6 (not shown in FIG. 11), and a compensation current line 28. Is done. The third embodiment has a configuration in which the second compensation current conductor 32 is added to the second embodiment, and overlapping portions in other configurations are omitted. In the third embodiment, based on the output voltage of the bridge circuit 18, a current that cancels out the magnetic fields generated in the vicinity of the four magnetoresistive effect elements 1 due to the current flowing through the current line to be measured 6, The compensation magnetic field is supplied from the sensor circuit unit 21 to the compensation current line 28 and a compensation magnetic field synthesized from the vertical direction of the magnetoresistive effect element 1 is applied.

この発明の実施の形態3による電流検知デバイス20の構成について説明する。
補償電流を印加する補償電流線28は、図11に示されるように第1の補償電流導体26(1点鎖線)、第2の補償電流導体32(2点鎖線)、および貫通接続補償電流線33(実線)により1本に接続され、第1の補償電流導体26は、第1の被測定導体3、絶縁層9および29を介して磁気抵抗効果素子1の上方に、第2の補償電流導体32は、第2の被測定導体4、絶縁層8および10を介して磁気抵抗効果素子1の下方に設置される。さらに第1の補償電流導体26、第2の補償電流導体32は磁気抵抗効果素子1で構成される被測定電流検出部14を面外で巻回するように貫通接続補償電流線33にて接続されており、図12において第1の被測定導体3の電流印加方向が紙面に垂直な手前方向であれば、第1の補償電流導体26の補償電流印加方向は紙面に垂直な奥行き方向となり、第2の被測定導体4の電流印加方向が紙面に垂直な奥行き方向であれば、第2の補償電流導体32の補償電流印加方向は紙面に垂直な手前方向となる。磁気抵抗効果素子1に効果的に補償電流による磁界を付与するために、可能な限り磁気抵抗効果素子1に接近して第1の補償電流導体26および第2の補償電流導体32を設置するのが望ましいが、電気的に絶縁され耐圧を確保する必要がある。第1、および第2の補償電流導体26、32、貫通接続補償電流線33には、例えば低抵抗材料であるアルミニウムや金などが選択され、絶縁層としては、例えばシリコン窒化膜やシリコン酸化膜、あるいはポリイミドなどの樹脂材料が選択される。電流検知デバイス20の内部構造は、例えば半導体微細加工技術により一貫して作製されるのが望ましく、各層の作製には、スパッタリング、CVD等の技術が利用される。これらの技術によれば、非常に寸法精度が高く、小型な電流検知デバイス20が作製できる。
A configuration of the current detection device 20 according to the third embodiment of the present invention will be described.
As shown in FIG. 11, the compensation current line 28 for applying the compensation current includes a first compensation current conductor 26 (one-dot chain line), a second compensation current conductor 32 (two-dot chain line), and a through-connection compensation current line. 33 (solid line), the first compensation current conductor 26 is connected above the magnetoresistive effect element 1 via the first conductor to be measured 3 and the insulating layers 9 and 29. The conductor 32 is installed below the magnetoresistive effect element 1 through the second measured conductor 4 and the insulating layers 8 and 10. Further, the first compensation current conductor 26 and the second compensation current conductor 32 are connected by a through-connection compensation current line 33 so as to wind the measured current detection unit 14 constituted by the magnetoresistive effect element 1 out of the plane. In FIG. 12, if the current application direction of the first conductor to be measured 3 is the front direction perpendicular to the paper surface, the compensation current application direction of the first compensation current conductor 26 is the depth direction perpendicular to the paper surface. If the current application direction of the second conductor to be measured 4 is the depth direction perpendicular to the paper surface, the compensation current application direction of the second compensation current conductor 32 is the front direction perpendicular to the paper surface. In order to effectively apply a magnetic field by a compensation current to the magnetoresistive effect element 1, the first compensation current conductor 26 and the second compensation current conductor 32 are installed as close to the magnetoresistive effect element 1 as possible. However, it is necessary to ensure electrical insulation and withstand voltage. For the first and second compensation current conductors 26 and 32 and the through-connection compensation current line 33, for example, a low resistance material such as aluminum or gold is selected, and as the insulating layer, for example, a silicon nitride film or a silicon oxide film is used. Alternatively, a resin material such as polyimide is selected. The internal structure of the current detection device 20 is desirably manufactured consistently by, for example, a semiconductor microfabrication technique, and techniques such as sputtering and CVD are used for manufacturing each layer. According to these techniques, the dimensional accuracy is very high, and the small current detection device 20 can be manufactured.

次に、電流検知デバイス20の動作について説明する。被測定電流線6に流れる電流の大きさに応じてブリッジ回路18の平衡が崩れる。このとき、センサ回路部21に設置された増幅回路部(例えばオペアンプ31)では、被測定電流検出部14の接続エリア16c、16dから検出される出力電圧に基づいて、磁気抵抗効果素子1a〜1d近傍に発生する磁界を打ち消すような電流(制御電流)を補償電流線28に供給する。具体的には接続エリア16c、16dの出力電圧が0になるように、制御電流の大きさを調整する。補償電流線28は、その制御電流の大きさに応じて4つの磁気抵抗効果素子1a〜1dの近傍に発生する磁界、すなわち被測定電流線6に流れる電流の大きさに応じた磁界を相殺するような磁界を印加磁界方向13cおよび印加磁界方向13dに発生し、磁気抵抗効果素子1においては合成された補償磁界方向30(1点鎖線矢印)となる。
したがって、被測定電流線6に流れる電流の大きさに応じたブリッジ回路18の平衡の崩れを、センサ回路部21から供給される制御電流により修復することができる。
ゆえに、センサ回路部21から供給した制御電流の大きさにより、被測定電流線6に流れる電流の大きさ、または被測定電流線6に流れる電流の大きさに相関のある値として検出することができる。
なお、被測定電流線6以外において発生された磁界(外乱磁界)は、磁気抵抗効果素子1a、1bと磁気抵抗効果素子1c、1d(ブリッジ回路の左右の各ハーフブリッジ回路)に同相の影響となるため、相殺され、測定精度に影響を与えない。
Next, the operation of the current detection device 20 will be described. The balance of the bridge circuit 18 is lost depending on the magnitude of the current flowing through the current line 6 to be measured. At this time, in the amplifier circuit unit (for example, the operational amplifier 31) installed in the sensor circuit unit 21, the magnetoresistive effect elements 1a to 1d are based on the output voltages detected from the connection areas 16c and 16d of the measured current detection unit 14. A current (control current) that cancels the magnetic field generated in the vicinity is supplied to the compensation current line 28. Specifically, the magnitude of the control current is adjusted so that the output voltage of the connection areas 16c and 16d becomes zero. The compensation current line 28 cancels out the magnetic field generated in the vicinity of the four magnetoresistive elements 1a to 1d according to the magnitude of the control current, that is, the magnetic field according to the magnitude of the current flowing through the current line 6 to be measured. Such a magnetic field is generated in the applied magnetic field direction 13c and the applied magnetic field direction 13d, and in the magnetoresistive effect element 1, the combined compensation magnetic field direction 30 (one-dot chain line arrow) is obtained.
Therefore, the loss of balance of the bridge circuit 18 according to the magnitude of the current flowing through the current line 6 to be measured can be repaired by the control current supplied from the sensor circuit unit 21.
Therefore, the magnitude of the control current supplied from the sensor circuit unit 21 can be detected as a value correlated with the magnitude of the current flowing through the measured current line 6 or the magnitude of the current flowing through the measured current line 6. it can.
It should be noted that the magnetic field (disturbance magnetic field) generated outside the current line 6 to be measured has the same effect on the magnetoresistive effect elements 1a and 1b and the magnetoresistive effect elements 1c and 1d (the left and right half bridge circuits of the bridge circuit). Therefore, it is offset and does not affect the measurement accuracy.

以上のように、この実施の形態3によれば、ブリッジ回路18の出力電圧に基づき、被測定電流線6に流れる電流に起因して4つの磁気抵抗効果素子1近傍に発生した磁界を打ち消すような電流を、センサ回路部21から付加した補償電流線28に供給する構成としたので、磁気抵抗効果素子1等の温度特性に起因した誤差が低減できるなどの効果が見込め、高精度化が可能となる。  As described above, according to the third embodiment, based on the output voltage of the bridge circuit 18, the magnetic fields generated in the vicinity of the four magnetoresistive effect elements 1 due to the current flowing through the current line 6 to be measured are canceled out. Since a current is supplied to the compensation current line 28 added from the sensor circuit unit 21, it is possible to reduce the error caused by the temperature characteristics of the magnetoresistive effect element 1 and the like, and the accuracy can be improved. It becomes.

さらに、図8の接続補償電流線27のような折り返し線が不用となるため、電流検知デバイス20がX方向に小型化できる効果がある。また、同一の補償電流でも実施の形態2に比べて2倍程度の補償磁界を磁気抵抗効果素子1に印加できるため、センサ回路部21の規模を小さく構成でき、センサの全体構成が小型化、低コスト化できる効果がある。  Further, since a folded line such as the connection compensation current line 27 in FIG. 8 is not required, there is an effect that the current detection device 20 can be reduced in size in the X direction. In addition, since the compensation magnetic field approximately twice that of the second embodiment can be applied to the magnetoresistive element 1 even with the same compensation current, the sensor circuit unit 21 can be reduced in size, and the overall configuration of the sensor can be reduced. There is an effect that the cost can be reduced.

実施の形態4.
図14は、この発明の実施の形態4による電流検知デバイス20の一部の断面図であり、図において、集磁部材35は第2の絶縁層9の内部で、各磁気抵抗効果素子1の両脇に設置したものである。実施の形態4は、実施の形態1に集磁部材35を付加した構成であり、その他の構成で重複する部分の説明は省略する。また、他の実施の形態に付加しても同等の効果を得るものであり、重複する説明は省略する。
この集磁部材35は、高透磁率を有する磁性材料で、例えば鉄など強磁性体の金属があるが、これに限定されるものではなく、半導体微細加工技術により一貫して作製される材料を選択するのが望ましい。この実施の形態4では、第2の絶縁層9内部に、各磁気抵抗効果素子1の両脇方向から挟み込むように集磁部材35を設置する形態であるが、被測定電流に起因した測定磁界、および補償電流に起因した補償磁界を共に効率よく磁気抵抗効果素子1に導く構成であればこれに限るものではなく、他の絶縁層に複数の集磁部材35を設置するのも良い。このように集磁部材35を設けることにより、各磁気抵抗効果素子1に印加する磁界の効率を上げることが可能となり被測定電流の検出精度がより向上する。
Embodiment 4 FIG.
FIG. 14 is a cross-sectional view of a part of the current detection device 20 according to the fourth embodiment of the present invention. In the figure, the magnetic flux collecting member 35 is disposed inside the second insulating layer 9 and is connected to each magnetoresistive effect element 1. Installed on both sides. The fourth embodiment is a configuration in which the magnetic flux collecting member 35 is added to the first embodiment, and the description of the overlapping parts in other configurations is omitted. Moreover, even if it adds to another embodiment, the same effect is acquired and the overlapping description is abbreviate | omitted.
The magnetic collecting member 35 is a magnetic material having a high magnetic permeability. For example, there is a ferromagnetic metal such as iron. However, the magnetic collecting member 35 is not limited to this material. It is desirable to choose. In the fourth embodiment, the magnetic collecting member 35 is installed in the second insulating layer 9 so as to be sandwiched from both sides of each magnetoresistive effect element 1, but the measurement magnetic field caused by the current to be measured is shown. In addition, the configuration is not limited to this as long as the compensation magnetic field caused by the compensation current is efficiently guided to the magnetoresistive effect element 1, and a plurality of magnetic flux collecting members 35 may be provided in another insulating layer. By providing the magnetic flux collecting member 35 in this way, the efficiency of the magnetic field applied to each magnetoresistive effect element 1 can be increased, and the detection accuracy of the current to be measured is further improved.

以上のように、この実施の形態4によれば、集磁部材35を設けるように構成したので、被測定電流に起因した測定磁界、および補償電流に起因した補償磁界を共に効率よく磁気抵抗効果素子1に印加でき、測定精度を向上させることができる。  As described above, according to the fourth embodiment, since the magnetic flux collecting member 35 is provided, both the measurement magnetic field caused by the current to be measured and the compensation magnetic field caused by the compensation current are both efficiently magnetoresistive. It can be applied to the element 1 and the measurement accuracy can be improved.

この発明の実施形態1による電流検知デバイスの一部の斜視模式図である。It is a one part perspective schematic diagram of the electric current detection device by Embodiment 1 of this invention. この発明の実施形態1による電流検知デバイスの一部の断面図である。It is sectional drawing of a part of electric current detection device by Embodiment 1 of this invention. この発明の実施形態1による電流検知デバイスの一部の拡大断面図である。It is a partial expanded sectional view of the electric current detection device by Embodiment 1 of this invention. この発明の実施形態1による電流検知デバイスの被測定電流検出部を示す平面図である。It is a top view which shows the to-be-measured current detection part of the current detection device by Embodiment 1 of this invention. この発明の実施形態1による電流検知デバイスの被測定電流検出部を示す構成概略図である。It is a structure schematic which shows the to-be-measured current detection part of the current detection device by Embodiment 1 of this invention. この発明の実施形態1による電流検知デバイスの電流センサ構成例であるIt is a current sensor structural example of the current detection device by Embodiment 1 of this invention. この発明の実施形態2による電流検知デバイスの一部の斜視模式図である。It is a one part perspective schematic diagram of the electric current detection device by Embodiment 2 of this invention. この発明の実施形態2による電流検知デバイスの一部の断面図である。It is sectional drawing of a part of electric current detection device by Embodiment 2 of this invention. この発明の実施形態2による電流検知デバイスの一部の拡大断面図である。It is a partial expanded sectional view of the electric current detection device by Embodiment 2 of this invention. この発明の実施形態2による補償電流線を配置した構成図である。It is the block diagram which has arrange | positioned the compensation current line by Embodiment 2 of this invention. この発明の実施形態3による電流検知デバイスの一部の斜視模式図である。It is a one part perspective schematic diagram of the electric current detection device by Embodiment 3 of this invention. この発明の実施形態3による電流検知デバイスの一部の断面図である。It is sectional drawing of a part of electric current detection device by Embodiment 3 of this invention. この発明の実施形態3による電流検知デバイスの一部の拡大断面図である。It is a partial expanded sectional view of the electric current detection device by Embodiment 3 of this invention. この発明の実施形態4による電流検知デバイスの一部の断面図である。It is sectional drawing of a part of electric current detection device by Embodiment 4 of this invention.

符号の説明Explanation of symbols

1 磁気抵抗効果素子、2 接続電流線、3 第1の被測定導体、4 第2の被測定導体、5 貫通接続電流線、6 被測定電流線、7 設置基板、8 第1の絶縁層、9 第2の絶縁層、10 第3の絶縁層、11 保護層、12 測定磁界方向、13 印加磁界方向、14 被測定電流検出部、15 中心線、16 接続エリア、17 ハーフブリッジ回路、18 ブリッジ回路、19 センサ基板、20 電流センサデバイス、21 センサ回路部、22 電流センサ、23 外部端子、24 電流端子、25 センサケース、26 第1の補償電流導体、27 接続補償電流線、28 補償電流線、29 第4の絶縁層、30 補償磁界方向、31 オペアンプ、32 第2の補償電流導体、33 貫通接続補償電流線、34 第5の絶縁層、35 集磁部材  DESCRIPTION OF SYMBOLS 1 Magnetoresistance effect element, 2 Connection current line, 3 1st to-be-measured conductor, 4 2nd to-be-measured conductor, 5 Through-connection current line, 6 To-be-measured current line, 7 Installation board, 8 1st insulating layer, 9 Second insulating layer, 10 3rd insulating layer, 11 Protective layer, 12 Measurement magnetic field direction, 13 Applied magnetic field direction, 14 Current detector, 15 Center line, 16 Connection area, 17 Half bridge circuit, 18 Bridge Circuit, 19 Sensor board, 20 Current sensor device, 21 Sensor circuit section, 22 Current sensor, 23 External terminal, 24 Current terminal, 25 Sensor case, 26 First compensation current conductor, 27 Connection compensation current line, 28 Compensation current line , 29 4th insulating layer, 30 compensation magnetic field direction, 31 operational amplifier, 32 second compensation current conductor, 33 feedthrough connection compensation current line, 34 5th insulation layer, 35 magnetism collecting member

Claims (5)

設置基板上に構成された第1の絶縁層上に配置され、互いに逆方向の磁界の増加に応じて抵抗値が共に増加する磁気抵抗効果特性を有する第1および第4の磁気抵抗効果素子と、
上記設置基板上に構成された第1の絶縁層上に配置され、互いに逆方向の上記磁界の増加に応じて抵抗値が共に減少する磁気抵抗効果特性を有する第2および第3の磁気抵抗効果素子と、
上記設置基板上に構成された第1の絶縁層上に配置され、上記第1から第4の磁気抵抗効果素子を接続することにより、上記第1および第2の磁気抵抗効果素子による第1のハーフブリッジ回路、および上記第3および第4の磁気抵抗効果素子による第2のハーフブリッジ回路からなるブリッジ回路を構成する接続電流線と、
上記設置基板上に構成された第2の絶縁層上に配置され、上記第1から第4の各磁気抵抗効果素子のそれぞれに対向して設置された第1の被測定電流導体と、上記設置基板上に構成された第3の絶縁層上に配置され、上記第1から第4の各磁気抵抗効果素子のそれぞれに対向して設置された第2の被測定電流導体と、上記設置基板上に上記絶縁層を面外方向に貫通して構成され、上記第1と第2の被測定電流導体を接続することにより被測定電流線を構成する貫通接続電流線とを備えた電流検知デバイスであって、
上記被測定電流線に被測定電流が印加されることにより、上記第1から第4の各磁気抵抗効果素子は対向して設置した上記第1および第2の被測定電流導体からそれぞれ同一方向の測定磁界が付与されるとともに、
第1および第2の磁気抵抗効果素子に付与される第1の測定磁界の方向と、第3および第4の磁気抵抗効果素子に付与される第2の測定磁界の方向が互いに逆方向となるように被測定電流線が構成されたことを特徴とする電流検知デバイス。
First and fourth magnetoresistive elements disposed on a first insulating layer formed on a mounting substrate and having magnetoresistive effect characteristics in which the resistance value increases in accordance with an increase in a magnetic field in the opposite direction to each other; ,
2nd and 3rd magnetoresistive effect which is arrange | positioned on the 1st insulating layer comprised on the said installation board | substrate, and has a magnetoresistive effect characteristic in which both resistance values reduce according to the increase of the said magnetic field of a mutually reverse direction Elements,
The first and second magnetoresistive effect elements are arranged on the first insulating layer formed on the installation substrate, and the first to fourth magnetoresistive effect elements are connected to each other. A connection current line constituting a bridge circuit composed of a half bridge circuit and a second half bridge circuit composed of the third and fourth magnetoresistive elements;
A first current-under-measurement conductor disposed on a second insulating layer configured on the installation substrate and disposed opposite to each of the first to fourth magnetoresistive elements; and the installation A second current-to-be-measured conductor disposed on a third insulating layer formed on the substrate and disposed opposite to each of the first to fourth magnetoresistive elements; and And a through-connection current line configured to pass through the insulating layer in an out-of-plane direction and connect the first and second measured current conductors to form a measured current line. There,
When a current to be measured is applied to the current line to be measured, the first to fourth magnetoresistive elements are arranged in the same direction from the first and second current conductors to be measured which are disposed to face each other. A measurement magnetic field is applied,
The direction of the first measurement magnetic field applied to the first and second magnetoresistance effect elements is opposite to the direction of the second measurement magnetic field applied to the third and fourth magnetoresistance effect elements. A current sensing device characterized in that a current wire to be measured is configured as described above.
上記第1から第4の各磁気抵抗効果素子は、第1の絶縁層上において、それぞれ複数かつ線状の素子パターンで構成されていることを特徴とする請求項1記載の電流検知デバイス。  2. The current detection device according to claim 1, wherein each of the first to fourth magnetoresistive elements is composed of a plurality of linear element patterns on the first insulating layer. 上記設置基板上に構成された第4の絶縁層上に配置され、上記第1から第4の各磁気抵抗効果素子のそれぞれに対向して設置された第1の補償電流導体と、上記設置基板上に構成された第4の絶縁層上に配置され、上記第1の補償電流導体を接続することにより補償電流線を構成する接続補償電流線とを備えた電流検知デバイスであって、
上記補償電流線に補償電流が印加されることにより、上記第1から第4の各磁気抵抗効果素子は対向して設置した上記第1の補償電流導体からそれぞれ同一方向の補償磁界が付与されるとともに、
第1および第2の磁気抵抗効果素子に付与される第1の補償磁界の方向と、第3および第4の磁気抵抗効果素子に付与される第2の補償磁界の方向が互いに逆方向となるように補償電流線が構成されたことを特徴とする請求項1または請求項2に記載の電流検知デバイス。
A first compensation current conductor disposed on a fourth insulating layer configured on the installation substrate and disposed opposite to each of the first to fourth magnetoresistive elements; and the installation substrate. A current sensing device comprising a connection compensation current line disposed on a fourth insulating layer configured above and constituting a compensation current line by connecting the first compensation current conductor;
When a compensation current is applied to the compensation current line, each of the first to fourth magnetoresistive effect elements is applied with a compensation magnetic field in the same direction from the first compensation current conductor disposed oppositely. With
The direction of the first compensation magnetic field applied to the first and second magnetoresistance effect elements is opposite to the direction of the second compensation magnetic field applied to the third and fourth magnetoresistance effect elements. The current sensing device according to claim 1, wherein the compensation current line is configured as described above.
上記設置基板上に構成された第4の絶縁層上に配置され、上記第1から第4の各磁気抵抗効果素子のそれぞれに対向して設置された第1の補償電流導体と、上記設置基板上に構成された第5の絶縁層上に配置され、上記第1から第4の各磁気抵抗効果素子のそれぞれに対向して設置された第2の補償電流導体と、上記設置基板上に上記絶縁層を面外方向に貫通して構成され、上記第1と第2の補償電流導体を接続することにより補償電流線を構成する貫通接続補償電流線とを備えた電流検知デバイスであって、
上記補償電流線に補償電流が印加されることにより、上記第1から第4の各磁気抵抗効果素子は対向して設置した上記第1および第2の補償電流導体からそれぞれ同一方向の補償磁界が付与されるとともに、
第1および第2の磁気抵抗効果素子に付与される第1の補償磁界の方向と、第3および第4の磁気抵抗効果素子に付与される第2の補償磁界の方向が互いに逆方向となるように補償電流線が構成されたことを特徴とする請求項1または請求項2に記載の電流検知デバイス。
A first compensation current conductor disposed on a fourth insulating layer configured on the installation substrate and disposed opposite to each of the first to fourth magnetoresistive elements; and the installation substrate. A second compensating current conductor disposed on the fifth insulating layer configured above and disposed opposite to each of the first to fourth magnetoresistive elements; and A current detection device comprising a through-connection compensation current line configured to penetrate through an insulating layer in an out-of-plane direction, and constituting a compensation current line by connecting the first and second compensation current conductors,
When a compensation current is applied to the compensation current line, each of the first to fourth magnetoresistive effect elements receives a compensation magnetic field in the same direction from the first and second compensation current conductors arranged to face each other. As well as
The direction of the first compensation magnetic field applied to the first and second magnetoresistance effect elements is opposite to the direction of the second compensation magnetic field applied to the third and fourth magnetoresistance effect elements. The current sensing device according to claim 1, wherein the compensation current line is configured as described above.
上記絶縁層の少なくとも1層において、絶縁層上または絶縁層内、または両方に少なくとも1つの集磁部材を備えたことを特徴とする請求項1から請求項4のうちいずれか1項記載の電流検知デバイス。  5. The current according to claim 1, wherein at least one of the insulating layers includes at least one magnetism collecting member on the insulating layer, in the insulating layer, or both. Detection device.
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