JP2000097972A - Current sensor - Google Patents

Current sensor

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Publication number
JP2000097972A
JP2000097972A JP10272200A JP27220098A JP2000097972A JP 2000097972 A JP2000097972 A JP 2000097972A JP 10272200 A JP10272200 A JP 10272200A JP 27220098 A JP27220098 A JP 27220098A JP 2000097972 A JP2000097972 A JP 2000097972A
Authority
JP
Japan
Prior art keywords
voltage
temperature
hall element
current
conversion element
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.)
Withdrawn
Application number
JP10272200A
Other languages
Japanese (ja)
Inventor
Soichi Kurino
荘一 栗野
Takeki Matsui
雄毅 松居
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Asahi Kasei Electronics Co Ltd
Original Assignee
Asahi Kasei Electronics Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Asahi Kasei Electronics Co Ltd filed Critical Asahi Kasei Electronics Co Ltd
Priority to JP10272200A priority Critical patent/JP2000097972A/en
Publication of JP2000097972A publication Critical patent/JP2000097972A/en
Withdrawn legal-status Critical Current

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Abstract

PROBLEM TO BE SOLVED: To make reducible a temperature drift by amplifying 2 output difference voltage of a magnetoelectric transducer driven by a heat-bonded constant current means, and controlling a mid-point voltage constantly. SOLUTION: The voltage of an output terminal of a Hall element 12 is divided, its voltage is applied to a non-inverting terminal of an amplifier 30, and a voltage of the other output terminal of the element 12 is applied to an inverting terminal of the amplifier 30 through a resistor 31. The difference voltage of the both is amplified by a differential amplifier 3, its gain is regulated by dividing an output of the amplifier 30 and negatively feeding back it. A temperature compensator 11 is heat coupled to the element 12 to increase or decrease a current value flowing from a positive power source to the element 12 according to rise or fall of the temperature of the sensor. The current from the element 12 is supplied to an output terminal of an amplifier 15, positive input voltage of the element 12 is applied to the inverting terminal through a resistor 16, the output voltage of the amplifier 15 is fed back through resistors 17=16, and the non-inverting terminal is grounded through a bias current compensating resistor 18. Thus, a mid-point voltage is controlled to the ground voltage.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、磁電変換素子を有
する電流センサに関する。
[0001] The present invention relates to a current sensor having a magnetoelectric conversion element.

【0002】[0002]

【従来の技術】従来から、エアコン、冷蔵庫、送風ファ
ン、送水ポンプ、コンベアのベルト駆動等のインバータ
モータの電流制御や、工作機械、電気自動車、ソーラ発
電システムのインバータモータ等の電流制御に、電流セ
ンサが使用されてきた。
2. Description of the Related Art Conventionally, current control for inverter motors such as an air conditioner, a refrigerator, a blower fan, a water pump, a belt drive of a conveyor, and current control of an inverter motor for a machine tool, an electric vehicle, and a solar power generation system has been performed. Sensors have been used.

【0003】広い使用温度で安定した動作をする電流セ
ンサとしては、図5に示す磁気計測型電流センサが知ら
れている。この電流センサは、ホール素子2としてIn
Asホール素子が用いられていて、ホール素子2の感度
が温度補償回路1により補償され、ホール素子2の2つ
の出力の差電圧が差動増幅回路3により増幅されるよう
になっている。
As a current sensor that operates stably at a wide operating temperature, a magnetic measurement type current sensor shown in FIG. 5 is known. This current sensor uses In as the Hall element 2.
As Hall elements are used, the sensitivity of the Hall element 2 is compensated by the temperature compensation circuit 1, and the differential voltage between the two outputs of the Hall element 2 is amplified by the differential amplifier circuit 3.

【0004】ホール素子2の感度はホール素子2に流す
電流に比例し、温度が上昇するにつれて減少する。この
ホール素子2の温度−感度特性の一例を図6に示す。
[0004] The sensitivity of the Hall element 2 is proportional to the current flowing through the Hall element 2, and decreases as the temperature rises. FIG. 6 shows an example of the temperature-sensitivity characteristics of the Hall element 2.

【0005】差動増幅回路3では、ホール素子2の一方
の出力端子の電圧が抵抗32と抵抗33により分圧さ
れ、得られた分圧がオペアンプ30の非反転端子に入力
され、ホール素子2の他方の出力端子の電圧が抵抗31
を介してオペアンプ30の反転端子に入力され、反転端
子の電圧と非反転端子の電圧の差電圧が増幅される。こ
の差動増幅回路3のゲインを調整するため、オペアンプ
30の出力電圧が可変抵抗36と抵抗35により分圧さ
れ、得られた分圧が負帰還抵抗34を介して反転端子に
帰還されている。
In the differential amplifier circuit 3, the voltage of one output terminal of the Hall element 2 is divided by the resistors 32 and 33, and the obtained divided voltage is input to the non-inverting terminal of the operational amplifier 30. Of the other output terminal of the
To the inverting terminal of the operational amplifier 30 to amplify the difference voltage between the inverting terminal voltage and the non-inverting terminal voltage. In order to adjust the gain of the differential amplifier circuit 3, the output voltage of the operational amplifier 30 is divided by the variable resistor 36 and the resistor 35, and the obtained divided voltage is fed back to the inverting terminal via the negative feedback resistor 34. .

【0006】温度補償回路1はホール素子2と熱結合さ
れていて、この電流センサの温度が上昇すると、上昇温
度に応じてホール素子2に流す電流値を大きくし、温度
が下降すると、下降温度に応じてホール素子2に流す電
流値を小さくするようになっていて、温度の変動に起因
する感度の変動を軽減させることができる。
The temperature compensating circuit 1 is thermally coupled to the Hall element 2. When the temperature of the current sensor rises, the value of the current flowing through the Hall element 2 increases according to the temperature rise. , The value of the current flowing through the Hall element 2 is reduced, and fluctuations in sensitivity due to fluctuations in temperature can be reduced.

【0007】[0007]

【発明が解決しようとする課題】しかし、温度の上昇に
つれて中点電圧が高くなるという問題があり、この電流
センサには、0.05%/℃の温度ドリフトがあった。
ホール素子2の温度−中点電圧特性の一例を図7に示
す。中点電圧とは、無磁界時におけるホール素子出力電
圧をいい、ホール素子駆動電源の正側電圧と負側電圧の
算術平均電圧とほぼ等しい値になる。
However, there is a problem that the midpoint voltage increases as the temperature rises, and this current sensor has a temperature drift of 0.05% / ° C.
One example of the temperature-midpoint voltage characteristic of the Hall element 2 is shown in FIG. The midpoint voltage refers to the Hall element output voltage in the absence of a magnetic field, and has a value substantially equal to the arithmetic average voltage of the positive voltage and the negative voltage of the Hall element driving power supply.

【0008】この中点電圧の変動に起因する温度ドリフ
トは、オペアンプ30と、抵抗31〜35と、可変抵抗
36によりなる差動増幅回路(図5)の同相信号除去比
(CMRR; common mode rejection ratio)を高くす
ることにより軽減することができるが、感度調整用の可
変抵抗36が負帰還系に挿入されていてこの抵抗値が不
定であるので、CMRRを高くするには限界があった。
The temperature drift caused by the fluctuation of the midpoint voltage is caused by the common mode signal rejection ratio (CMRR; common mode) of the differential amplifier circuit (FIG. 5) including the operational amplifier 30, the resistors 31 to 35, and the variable resistor 36. The rejection ratio can be reduced by increasing the rejection ratio. However, since the variable resistor 36 for adjusting the sensitivity is inserted in the negative feedback system and the resistance value is indefinite, there is a limit in increasing the CMRR. .

【0009】また、この問題は、感度調整部分をさらに
別の増幅器を設置して解決することができるが、このよ
うにするには、差動増幅回路の抵抗に高精度のものを使
用するとともに、オペアンプとしても高CMRRのもの
を採用する必要があり、却って、電流センサのコストが
高くなるという問題があった。
This problem can be solved by installing another amplifier in the sensitivity adjusting portion. To achieve this, a high-precision resistor must be used for the differential amplifier circuit. In addition, it is necessary to employ an operational amplifier having a high CMRR, and there is a problem that the cost of the current sensor is rather increased.

【0010】そこで、本発明の目的は、上記のような問
題点を解決し、温度ドリフトをより低減することができ
る電流センサを提供することにある。
Accordingly, an object of the present invention is to provide a current sensor which can solve the above-described problems and can further reduce temperature drift.

【0011】[0011]

【課題を解決するための手段】本発明の電流センサは、
磁界の強さを電圧に変換する磁電変換素子と、該磁電変
換素子と熱結合してあり該磁電変換素子を定電流駆動す
る定電流駆動手段と、該定電流駆動手段により定電流駆
動された磁電変換素子の出力差電圧を増幅する差動増幅
器と、前記磁電変換素子の中点電圧を所定の電圧になる
ように制御する制御手段とを備えている。
The current sensor according to the present invention comprises:
A magnetoelectric conversion element for converting the strength of the magnetic field into a voltage, a constant current driving means thermally coupled to the magnetoelectric conversion element and driving the magnetoelectric conversion element at a constant current, and a constant current drive by the constant current driving means. A differential amplifier for amplifying the output difference voltage of the magnetoelectric conversion element, and control means for controlling the midpoint voltage of the magnetoelectric conversion element to a predetermined voltage are provided.

【0012】定電流駆動手段は温度に応じた電流を前記
磁電変換素子に流し込むことができる。定電流駆動手段
は温度に応じた電流を前記磁電変換素子から流し出すこ
とができる。
[0012] The constant current driving means can supply a current corresponding to the temperature to the magnetoelectric conversion element. The constant current driving means can supply a current according to the temperature from the magnetoelectric conversion element.

【0013】制御手段は、磁電変換素子の一方の入力端
子の電圧と電圧が等しく極性が異なる電圧を該磁電変換
素子の他方の入力端子に印加することができる。
The control means can apply to the other input terminal of the magnetoelectric conversion element a voltage having the same voltage as the voltage of one input terminal of the magnetoelectric conversion element and having a different polarity.

【0014】[0014]

【発明の実施の形態】以下、本発明の実施の形態を図面
を参照して詳細に説明する。本発明は以下の実施の形態
に限定されるものでないことは勿論である。
Embodiments of the present invention will be described below in detail with reference to the drawings. The present invention is, of course, not limited to the following embodiments.

【0015】<第1実施の形態>図1は本発明の第1の
実施の形態を示す。これは磁気計測型電流センサの例で
ある。図1において、12はホール素子であって、In
Asホール素子であり、図5に示すホール素子2と同一
特性を有する。3は差動増幅回路であって、図5と同一
部分を示し、ホール素子12の一方の出力端子の電圧を
抵抗32と抵抗33により分圧し、得られた分圧をオペ
アンプ30の非反転端子に印加させ、ホール素子2の他
方の出力端子の電圧を抵抗31を介してオペアンプ30
の反転端子に印加させ、反転端子の電圧と非反転端子の
電圧の差電圧を増幅するものであり、この差動増幅回路
3のゲインを調整するため、オペアンプ30の出力電圧
を可変抵抗36と抵抗35により分圧し、得られた分圧
を負帰還抵抗34を介して反転端子に帰還させている。
11は温度補償回路であって、図5に示す温度補償回路
1と同一構成を有し、ホール素子12と熱結合してあ
り、この電流センサの温度が上昇すると、上昇温度に応
じて正電源からホール素子12に流す電流値を大きく
し、温度が下降すると、下降温度に応じて正電源からホ
ール素子12に流す電流値を小さくするようになってい
る。
<First Embodiment> FIG. 1 shows a first embodiment of the present invention. This is an example of a magnetic measurement type current sensor. In FIG. 1, reference numeral 12 denotes a Hall element,
This is an As Hall element and has the same characteristics as the Hall element 2 shown in FIG. Reference numeral 3 denotes a differential amplifier circuit, which is the same as that shown in FIG. 5, and divides the voltage of one output terminal of the Hall element 12 by the resistors 32 and 33, and divides the obtained voltage into the non-inverting terminal , And the voltage of the other output terminal of the Hall element 2 is applied via the resistor 31 to the operational amplifier 30.
To amplify the difference voltage between the voltage of the inverting terminal and the voltage of the non-inverting terminal. In order to adjust the gain of the differential amplifier circuit 3, the output voltage of the operational amplifier 30 is connected to the variable resistor 36. The voltage is divided by the resistor 35, and the obtained voltage is fed back to the inverting terminal via the negative feedback resistor 34.
Reference numeral 11 denotes a temperature compensating circuit which has the same configuration as the temperature compensating circuit 1 shown in FIG. 5, is thermally coupled to the Hall element 12, and when the temperature of the current sensor rises, a positive power supply When the temperature decreases, the value of the current flowing from the positive power supply to the Hall element 12 decreases in accordance with the temperature decrease.

【0016】15はオペアンプであり、この出力端子に
は、ホール素子12からの電流を吸い込ませ、反転端子
には、ホール素子12の正側入力電圧を抵抗16を介し
て印加させるとともに、このオペアンプ15の出力電圧
を抵抗17(抵抗16と抵抗17は抵抗値が同一であ
る)を介して帰還させてあり、非反転端子はバイアス電
流補償用抵抗18を介してグランドに接続してある。
Numeral 15 denotes an operational amplifier. An output terminal of the operational amplifier sucks a current from the Hall element 12, and an inverting terminal of the operational amplifier applies a positive input voltage of the Hall element 12 through a resistor 16. The output voltage 15 is fed back via a resistor 17 (the resistors 16 and 17 have the same resistance value), and the non-inverting terminal is connected to the ground via a bias current compensation resistor 18.

【0017】本実施の形態の電流センサは、抵抗16と
抵抗17の抵抗値を同一にしたので、ホール素子12の
一方の入力端子の電圧をVhとした場合、オペアンプ1
5の出力端子の電圧が−Vhになり、ホール素子12の
他方の入力端子の電圧が−Vhになる。従って、中点電
圧Vmは、
In the current sensor according to the present embodiment, since the resistance values of the resistor 16 and the resistor 17 are the same, when the voltage of one input terminal of the Hall element 12 is Vh, the operational amplifier 1
5, the voltage at the output terminal becomes -Vh, and the voltage at the other input terminal of the Hall element 12 becomes -Vh. Therefore, the midpoint voltage Vm is

【0018】[0018]

【数1】 Vm={(ホール素子12の一方の入力端子の電圧)+
(ホール素子12の他方の入力端子の電圧)}/2 =(Vh+(−Vh))/2 =0 となり、中点電圧Vmがグランド電圧になるように制御
される。温度−中点電圧の関係の一例を図2に示す。図
2から分かるように、本実施の形態での温度ドリフト
(図2に*で示す)は、従来例の温度ドリフト(図2に
■で示す)より軽減されている。
Vm = {(voltage of one input terminal of Hall element 12) +
(The voltage of the other input terminal of the Hall element 12)} / 2 = (Vh + (− Vh)) / 2 = 0, and the midpoint voltage Vm is controlled to be the ground voltage. FIG. 2 shows an example of the relationship between the temperature and the midpoint voltage. As can be seen from FIG. 2, the temperature drift (indicated by * in FIG. 2) in the present embodiment is less than the temperature drift in the conventional example (indicated by Δ in FIG. 2).

【0019】<第2の実施の形態>図3は本発明の第2
の実施の形態を示す。図3において、3,12は図1と
同一部分を示す。21は温度補償回路であって、ホール
素子12と熱結合してあり、電流センサの温度が上昇す
ると、上昇温度に応じて負電源に流す電流、すなわち、
ホール素子12から流れ出す電流値を大きくし、温度が
下降すると、下降温度に応じて負電源に流す電流、すな
わち、ホール素子12から流れ出す電流値を小さくする
ようになっている。25はオペアンプであり、この出力
端子からホール素子12に電流を流し込み、反転端子に
は、ホール素子12の他方の入力端子の電圧を抵抗26
を介して印加させるとともに、このオペアンプ15の出
力電圧を抵抗27(抵抗26と抵抗27は抵抗値が同一
である)を介して帰還させてあり、非反転端子はバイア
ス電流補償用抵抗28を介してグランドに接続してあ
る。
<Second Embodiment> FIG. 3 shows a second embodiment of the present invention.
An embodiment will be described. 3, reference numerals 3 and 12 denote the same parts as in FIG. Reference numeral 21 denotes a temperature compensation circuit, which is thermally coupled to the Hall element 12 and, when the temperature of the current sensor rises, a current flowing to a negative power supply according to the rise temperature, that is,
When the current value flowing out of the Hall element 12 is increased and the temperature decreases, the current flowing to the negative power supply according to the temperature decrease, that is, the current value flowing out of the Hall element 12 is reduced. Reference numeral 25 denotes an operational amplifier. A current flows from the output terminal to the Hall element 12, and the voltage of the other input terminal of the Hall element 12 is supplied to the inverting terminal by a resistor 26.
And the output voltage of the operational amplifier 15 is fed back via a resistor 27 (the resistors 26 and 27 have the same resistance value), and the non-inverting terminal is passed through a bias current compensation resistor 28. Connected to ground.

【0020】本実施の形態の電流センサは、抵抗26と
抵抗27の抵抗値を同一にしたので、ホール素子12の
一方の入力端子の電圧をVhとした場合、オペアンプ1
5の出力端子の電圧が−Vhになり、ホール素子12の
他方の入力端子の電圧が−Vhになる。従って、中点電
圧Vmは、
In the current sensor of the present embodiment, since the resistances of the resistor 26 and the resistor 27 are the same, when the voltage of one input terminal of the Hall element 12 is Vh, the operational amplifier 1
5, the voltage at the output terminal becomes -Vh, and the voltage at the other input terminal of the Hall element 12 becomes -Vh. Therefore, the midpoint voltage Vm is

【0021】[0021]

【数2】 Vm={(ホール素子12の一方の入力端子の電圧)+
(ホール素子12の他方の入力端子の電圧)}/2 =(Vh+(−Vh))/2 =0 となり、中点電圧Vmがグランド電圧になるように制御
される。この場合の温度−中点電圧の関係も図2に示す
ようになり、図2から、本実施の形態でも、温度ドリフ
ト(図2に*で示す)が従来例の温度ドリフト(図2に
■で示す)より軽減されていることが分かる。
Vm = {(voltage of one input terminal of Hall element 12) +
(The voltage of the other input terminal of the Hall element 12)} / 2 = (Vh + (− Vh)) / 2 = 0, and the midpoint voltage Vm is controlled to be the ground voltage. In this case, the relationship between the temperature and the midpoint voltage is also as shown in FIG. 2. From FIG. 2, it can be seen from FIG. It can be seen that it is reduced.

【0022】<第3の実施の形態>図4は本発明の第3
の実施の形態を示す。図4において、3,11,12は
図1と同一部分を示す。45はオペアンプであり、反転
端子には、ホール素子12の一方の出力端子の電圧を抵
抗46を介して印加してあり、非反転端子はバイアス電
流補償用抵抗48を介してグランドに接続してあり、出
力端子はホール素子12の他方の入力端子に接続してあ
る。
<Third Embodiment> FIG. 4 shows a third embodiment of the present invention.
An embodiment will be described. 4, 3, 11, and 12 indicate the same parts as those in FIG. Reference numeral 45 denotes an operational amplifier. The voltage of one output terminal of the Hall element 12 is applied to the inverting terminal via a resistor 46, and the non-inverting terminal is connected to ground via a bias current compensating resistor 48. The output terminal is connected to the other input terminal of the Hall element 12.

【0023】本実施の形態の電流センサは、このように
構成したので、ホール素子12の一方の出力端子は、常
に、グランド電圧になるように、オペアンプ45により
制御され、ホール素子12の他方の出力端子には、ホー
ル素子12の受ける磁界の強さに比例した出力電圧が現
れる。
Since the current sensor of the present embodiment is configured as described above, one output terminal of the Hall element 12 is controlled by the operational amplifier 45 so as to be always at the ground voltage, and the other output terminal of the Hall element 12 is controlled. At the output terminal, an output voltage proportional to the strength of the magnetic field received by the Hall element 12 appears.

【0024】ホール素子12の一方の出力端子が常にグ
ランド電圧になるので、ホール素子12の出力を増幅す
るオペアンプ30と、抵抗31〜35と、可変抵抗36
とによりなる増幅回路のCMRRが低くても、入力電圧
変動に起因するドリフトを排除することができる。
Since one output terminal of the Hall element 12 is always at the ground voltage, the operational amplifier 30 for amplifying the output of the Hall element 12, the resistors 31 to 35, and the variable resistor 36
Even if the CMRR of the amplifier circuit is low, it is possible to eliminate drift caused by input voltage fluctuation.

【0025】以上、第1ないし第3の実施の形態では、
磁電変換素子としてInAsホール素子を使用した例を
説明したが、インジウムアンチモン、ガリウム砒素のホ
ール素子か、あるいは、それらの2種以上からなる3元
または4元の化合物半導体から作られたホール素子やシ
リコンホール素子を使用しても良い。また、いわゆる量
子効果素子も使用できる。当然、温度により感度やオフ
セット電圧が小さいものが好適に使用できる。さらに、
強磁性体MRやGMRあるいは半導体MRといった他の
磁電変換素子も好適に使用できる。また、電流センサに
作り込むために、より薄いあるいはより小さい磁電変換
素子が好ましい。
As described above, in the first to third embodiments,
An example in which an InAs Hall element is used as the magnetoelectric conversion element has been described. However, a Hall element made of indium antimony or gallium arsenide, or a Hall element made of a ternary or quaternary compound semiconductor composed of two or more of these elements, A silicon Hall element may be used. Also, a so-called quantum effect element can be used. Naturally, those having a small sensitivity or offset voltage depending on the temperature can be suitably used. further,
Other magnetoelectric elements, such as ferromagnetic MR, GMR, or semiconductor MR, can also be used suitably. In addition, a thinner or smaller magneto-electric conversion element is preferable in order to incorporate it into the current sensor.

【0026】[0026]

【発明の効果】以上説明したように、本発明によれば、
上記のように構成したので、温度ドリフトをより低減さ
せることができる。
As described above, according to the present invention,
With the configuration described above, the temperature drift can be further reduced.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明の第1の実施の形態を示す回路図であ
る。
FIG. 1 is a circuit diagram showing a first embodiment of the present invention.

【図2】温度−ドリフト特性の一例と、温度−中点電圧
特性の一例とを示す図である。
FIG. 2 is a diagram illustrating an example of a temperature-drift characteristic and an example of a temperature-midpoint voltage characteristic.

【図3】本発明の第2の実施の形態を示す回路図であ
る。
FIG. 3 is a circuit diagram showing a second embodiment of the present invention.

【図4】本発明の第3の実施の形態を示す回路図であ
る。
FIG. 4 is a circuit diagram showing a third embodiment of the present invention.

【図5】従来の電流センサの構成を示す回路図である。FIG. 5 is a circuit diagram showing a configuration of a conventional current sensor.

【図6】ホール素子の温度特性の一例を示す図である。FIG. 6 is a diagram showing an example of a temperature characteristic of a Hall element.

【図7】温度−中点電圧特性の一例を示す図である。FIG. 7 is a diagram illustrating an example of a temperature-midpoint voltage characteristic.

【符号の説明】[Explanation of symbols]

2 ホール素子 3 差動増幅回路 11,21 温度補償回路 15,25,30,45 オペアンプ 2 Hall element 3 Differential amplifier circuit 11, 21 Temperature compensation circuit 15, 25, 30, 45 Operational amplifier

───────────────────────────────────────────────────── フロントページの続き Fターム(参考) 2G025 AA08 AB02 5J090 AA03 AA42 AA47 CA02 CA12 CA13 CN01 FA05 FA08 FA09 FA17 FN01 FN10 FN14 HA25 HA26 HA42 HN07 HN14 KA01 KA02 KA05 KA17 KA28 KA48 MA13 MA20 MA23 MN02 MN04 NN03 NN06 TA01 TA04  ──────────────────────────────────────────────────続 き Continuing on the front page F term (reference) 2G025 AA08 AB02 5J090 AA03 AA42 AA47 CA02 CA12 CA13 CN01 FA05 FA08 FA09 FA17 FN01 FN10 FN14 HA25 HA26 HA42 HN07 HN14 KA01 KA02 KA05 KA17 KA28 KA48 MA13 MA20 MA03 NN

Claims (4)

【特許請求の範囲】[Claims] 【請求項1】 磁界の強さを電圧に変換する磁電変換素
子と、 該磁電変換素子と熱結合してあり該磁電変換素子を定電
流駆動する定電流駆動手段と、 該定電流駆動手段により定電流駆動された磁電変換素子
の出力差電圧を増幅する差動増幅器と、 前記磁電変換素子の中点電圧を所定の電圧になるように
制御する制御手段とを備えたことを特徴とする電流セン
サ。
1. A magnetoelectric conversion element for converting the strength of a magnetic field into a voltage, a constant current driving means thermally coupled to the magnetoelectric conversion element and driving the magnetoelectric conversion element with a constant current, and a constant current driving means. A current comprising: a differential amplifier for amplifying an output difference voltage of a magnetoelectric conversion element driven by a constant current; and control means for controlling a midpoint voltage of the magnetoelectric conversion element to a predetermined voltage. Sensor.
【請求項2】 請求項1において、前記定電流駆動手段
は、温度に応じた電流を前記磁電変換素子に流し込むこ
とを特徴とする電流センサ。
2. The current sensor according to claim 1, wherein said constant current driving means causes a current corresponding to a temperature to flow into said magnetoelectric conversion element.
【請求項3】 請求項1において、前記定電流駆動手段
は、温度に応じた電流を前記磁電変換素子から流し出す
ことを特徴とする電流センサ。
3. The current sensor according to claim 1, wherein said constant current driving means causes a current corresponding to a temperature to flow out of said magnetoelectric conversion element.
【請求項4】 請求項1において、前記制御手段は、前
記磁電変換素子の一方の入力端子の電圧と電圧が等しく
極性が異なる電圧を該磁電変換素子の他方の入力端子に
印加することを特徴とする電流センサ。
4. The magneto-optical device according to claim 1, wherein the control means applies a voltage having the same voltage as that of one input terminal of the magneto-electric conversion element and having a different polarity to the other input terminal of the magneto-electric conversion element. Current sensor.
JP10272200A 1998-09-25 1998-09-25 Current sensor Withdrawn JP2000097972A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10272200A JP2000097972A (en) 1998-09-25 1998-09-25 Current sensor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10272200A JP2000097972A (en) 1998-09-25 1998-09-25 Current sensor

Publications (1)

Publication Number Publication Date
JP2000097972A true JP2000097972A (en) 2000-04-07

Family

ID=17510502

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10272200A Withdrawn JP2000097972A (en) 1998-09-25 1998-09-25 Current sensor

Country Status (1)

Country Link
JP (1) JP2000097972A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003035730A (en) * 2001-07-24 2003-02-07 Setto Engineering:Kk Current detector
EP1632779A1 (en) * 2004-08-31 2006-03-08 Texas Instruments Deutschland Gmbh Hall sensor module and integrated circuit for use with an external Hall sensor
KR100676212B1 (en) 2006-01-05 2007-01-30 (주)에이디테크놀로지 Hall sensor driving circuit and pointing apparatus thereof
CN100417880C (en) * 2003-05-22 2008-09-10 乐金电子(天津)电器有限公司 Acoustic quality improvement circuit for Internet electric refrigerator
JP2010127636A (en) * 2008-11-25 2010-06-10 Tdk Corp Magnetic proportion system current sensor
JP2014190862A (en) * 2013-03-27 2014-10-06 Asahi Kasei Electronics Co Ltd Hall element driving circuit and hall element driving method
JP2017078646A (en) * 2015-10-21 2017-04-27 甲神電機株式会社 Sensor using bridge type sensor element, and bottom side voltage adjustment circuit of sensor element
JP2022054256A (en) * 2020-09-25 2022-04-06 横河電機株式会社 Current sensor

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003035730A (en) * 2001-07-24 2003-02-07 Setto Engineering:Kk Current detector
CN100417880C (en) * 2003-05-22 2008-09-10 乐金电子(天津)电器有限公司 Acoustic quality improvement circuit for Internet electric refrigerator
EP1632779A1 (en) * 2004-08-31 2006-03-08 Texas Instruments Deutschland Gmbh Hall sensor module and integrated circuit for use with an external Hall sensor
KR100676212B1 (en) 2006-01-05 2007-01-30 (주)에이디테크놀로지 Hall sensor driving circuit and pointing apparatus thereof
JP2010127636A (en) * 2008-11-25 2010-06-10 Tdk Corp Magnetic proportion system current sensor
JP2014190862A (en) * 2013-03-27 2014-10-06 Asahi Kasei Electronics Co Ltd Hall element driving circuit and hall element driving method
JP2017078646A (en) * 2015-10-21 2017-04-27 甲神電機株式会社 Sensor using bridge type sensor element, and bottom side voltage adjustment circuit of sensor element
JP2022054256A (en) * 2020-09-25 2022-04-06 横河電機株式会社 Current sensor

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