JPH0454458A - Current detector - Google Patents
Current detectorInfo
- Publication number
- JPH0454458A JPH0454458A JP16265390A JP16265390A JPH0454458A JP H0454458 A JPH0454458 A JP H0454458A JP 16265390 A JP16265390 A JP 16265390A JP 16265390 A JP16265390 A JP 16265390A JP H0454458 A JPH0454458 A JP H0454458A
- Authority
- JP
- Japan
- Prior art keywords
- current
- resistor
- current detection
- resistance element
- temperature compensation
- 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.)
- Pending
Links
- 238000001514 detection method Methods 0.000 claims abstract description 107
- 238000010438 heat treatment Methods 0.000 claims description 27
- 239000002245 particle Substances 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 2
- 229910052751 metal Inorganic materials 0.000 claims description 2
- 239000000758 substrate Substances 0.000 claims 1
- 238000000034 method Methods 0.000 description 9
- 238000010586 diagram Methods 0.000 description 4
- 238000001816 cooling Methods 0.000 description 3
- 238000000609 electron-beam lithography Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000012212 insulator Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000005476 soldering Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Measurement Of Current Or Voltage (AREA)
- Thermistors And Varistors (AREA)
Abstract
Description
（産業上の利用分野］
本発明は、電流検出装置の改良に関し、とくに、検出す
べき電流が流れる電流通路に電流検出用抵抗を直列に挿
入し、該電流検出用抵抗の両端間電圧を検出して、上記
電流通路に流れる電流値を検知する方式による電流検出
装置の改良に関する。
ｒ従来の技術】
電子線描画装置や走査型電子顕微鏡などの荷電粒子線応
用装置においては、荷電粒子線の集束状態や偏向状態な
どを制御するために、集束レンズコイルや偏向コイルな
ど多くの電磁コイル類が使われている。これら電磁コイ
ルの線材には通常銅線が用いられているため、コイル自
体が有する抵抗値の温度安定性が著しく悪い、このため
、これら電磁コイルに安定な励磁電流を流してやるため
には、何らかの安定化対策を講じることが必要である。
安定な励磁電流を流してやるための対策として、通常は
、電流検出装置を用いて、実際にコイルに流れている電
流を検出し、該検出電流値が本来流すべき電流値と一致
するように制御することが行なわれている。すなわち、
従来一般には、第２図に示すような回路構成を用い、コ
イル３に流れる電流（Ｉ）を電流検出抵抗Ｒｓを用いて
その両端間電圧として検出し、該検出電圧と入力電圧（
Ｖ ｓ ）との差分がゼロ（微小な一定値）となるよう
に、アンプ２を用いて負帰還制御する方式が採られてい
る。このような回路構成としたときのコイル電流工は。
■ ： Ｖｓ／Ｒｓ
・・・・・（１）
となることは周知である。したがって、抵抗値温度係数
の優れた電流検出抵抗を用いれば、入力電圧（Ｖ ｓ
）に対応した安定な電流（Ｉ）をコイル３に流すことが
できる。しかし、電子線描画装置に用いられる偏向アン
プにおけるように、電流（Ｉ）の大きさがランダムに変
化するような場合には、電流検出抵抗Ｒｓの自己発熱量
の変化による抵抗値変化が問題になる。
具体的−例として、電流検出抵抗Ｒｓは、抵抗値が１０
Ω、抵抗温度係数がＩＱｐｐｍ／’Ｃ１電力消費に伴う
自己発熱が１０℃／Ｗであるとする。
このような特性の抵抗Ｒｓに、いま、ＩＡの電流が流れ
たとすると、該抵抗ＲｓはＩＯＷの電力を消費するので
、１００℃の温度上昇が生じる。したがって、室温が変
化しなくても、ＩＡの電流を流したことにより、１１０
００ｐｐの抵抗値変化が生じてしまうことになる。すな
わち、安定であるべき電流は１１０００ｐｐも変化して
しまうことになる。
このような自己発熱による温度上昇によって生じる抵抗
値変化の問題を避けるため、従来は、以下に挙げるよう
な種々の対策方法が採られている。
すなわち、
１）温度上昇が生じないように、多数個の抵抗を使う。
２）比較的多数個の抵抗を使い、各抵抗は温度特性が互
いに打消しあう性質のものを組み合わせて使う。
３）抵抗の表面を水冷などの方法によって冷却する。
上記１）、２）の方法は、最も良く行なわれている方法
ではあるが、抵抗の個数が増えるほど抵抗と抵抗との接
続部材の影響が出てくる０例えば、プリント基板に抵抗
を実装する場合では、基板の銅箔部の持つ抵抗成分の温
度特性の影響や、ハンダ付は部分の熱起電力の影響が出
てくる等、新たな問題が生じてくる。この他にも、高価
な抵抗を多数個使うことはコストアップになるという欠
点もある。
上記３）の方法は、数十Ｗ以上の電力を消費するような
場合に良く使われる方法である。このような冷却方式と
したときの問題は、抵抗体と冷却媒体との間の熱抵抗あ
るいは熱時定数による冷却の遅れが生じることである。
この理由により、流れる電流の大きさが変化すると、こ
れに伴なって抵抗値は最初はやはり変化してしまう、そ
して、徐々に冷やされていくことによって１元の抵抗値
に戻っていくというような変化をする。したがって、レ
ンズ電源などのように、常に一定の大きさの電流を流し
てやるような使い方をする場合には適しているが、偏向
アンプのように、電流の大きさが常に変化するような場
合には適さない。(Industrial Application Field) The present invention relates to improvement of a current detection device, and in particular, a current detection resistor is inserted in series in a current path through which a current to be detected flows, and a voltage across the current detection resistor is detected. This invention relates to an improvement of a current detection device using a method of detecting the value of the current flowing in the current path. rPrior art] In charged particle beam application devices such as electron beam lithography devices and scanning electron microscopes, charged particle beam Many electromagnetic coils, such as focusing lens coils and deflection coils, are used to control the focusing state and deflection state.Since copper wire is usually used for the wire material of these electromagnetic coils, the coil itself The temperature stability of the resistance value of these electromagnetic coils is extremely poor. Therefore, it is necessary to take some stabilization measures in order to supply a stable excitation current to these electromagnetic coils. As a countermeasure, usually a current detection device is used to detect the current actually flowing through the coil, and control is performed so that the detected current value matches the current value that should originally be flowing. ,
Conventionally, in general, using a circuit configuration as shown in FIG. 2, the current (I) flowing through the coil 3 is detected as the voltage across it using a current detection resistor Rs, and the detected voltage and the input voltage (
A negative feedback control method is adopted using the amplifier 2 so that the difference with Vs) becomes zero (a small constant value). What is the coil electric current when the circuit is configured like this? ■: Vs/Rs (1) It is well known that. Therefore, if a current detection resistor with an excellent temperature coefficient of resistance value is used, the input voltage (V s
) can be passed through the coil 3. However, when the magnitude of the current (I) changes randomly, such as in a deflection amplifier used in an electron beam lithography system, resistance value changes due to changes in the self-heating amount of the current detection resistor Rs become a problem. Become. Specifically, as an example, the current detection resistor Rs has a resistance value of 10
Ω, resistance temperature coefficient is IQppm/'C1, self-heating due to power consumption is 10°C/W. If a current of IA flows through a resistor Rs having such characteristics, the resistor Rs consumes power of IOW, resulting in a temperature rise of 100°C. Therefore, even if the room temperature does not change, by passing a current of IA, 110
This results in a resistance value change of 00 pp. In other words, the current that should be stable changes by as much as 11,000 pp. In order to avoid the problem of resistance value change caused by temperature rise due to self-heating, various countermeasures such as those listed below have been conventionally adopted. That is, 1) Use a large number of resistors to prevent temperature rise. 2) A relatively large number of resistors are used, and each resistor is a combination of resistors whose temperature characteristics cancel each other out. 3) Cool the surface of the resistor by water cooling or other methods. Methods 1) and 2) above are the most commonly used methods, but as the number of resistors increases, the influence of the connecting members between the resistors increases.For example, mounting resistors on a printed circuit board In some cases, new problems arise, such as the influence of the temperature characteristics of the resistance component of the copper foil part of the board, and the influence of thermoelectromotive force of the soldering part. Another drawback is that using a large number of expensive resistors increases costs. Method 3) above is often used in cases where several tens of W or more of power is consumed. A problem with such a cooling method is that there is a delay in cooling due to thermal resistance or thermal time constant between the resistor and the cooling medium. For this reason, when the magnitude of the flowing current changes, the resistance value initially changes accordingly, and then gradually returns to the original resistance value as it cools down. make a change. Therefore, it is suitable for applications where a constant amount of current always flows, such as in a lens power supply, but it is suitable for applications where the current magnitude always changes, such as in a deflection amplifier. is not suitable.
以上説明してきたように、従来の電流検出装置における
電流検出抵抗の抵抗値変化防止対策には、それぞれ一長
一短があり、全ての要請に同時に応え得るような最適な
抵抗値変化防止対策は無いというのが現状である。
したがって、本発明の目的は、電流検出抵抗に流れる電
流の大きさが変化しても、そのことによっては該電流検
出抵抗の抵抗値に変化が生じないように構成された電流
検出装置を提供することである。As explained above, each of the measures to prevent changes in resistance value of the current detection resistor in conventional current detection devices has its advantages and disadvantages, and there is no optimal measure to prevent changes in resistance value that can simultaneously meet all demands. is the current situation. Therefore, an object of the present invention is to provide a current detection device configured such that even if the magnitude of the current flowing through the current detection resistor changes, the resistance value of the current detection resistor does not change due to the change in the magnitude of the current flowing through the current detection resistor. That's true.
電流検出抵抗に流れる電流の大きさが変化しても、該電
流検出抵抗の抵抗値が変わらないようにするためには、
流れる電流値が変化して該電流検出抵抗の消費電力が変
わっても、該電流検出抵抗の温度が変わらないような手
段を講じてやればよい。
このために、本発明においては、電流が流れる通路に抵
抗要素を直列に挿入し、該抵抗要素の両端間電圧を検出
して、上記電流の大きさを検知する電流検出装置におい
て、上記抵抗要素を外部から加熱する手段と、該抵抗要
素に流れる電流の大きさに応じて、上記加熱手段による
該抵抗要素の加熱量を制御する手段とを付設し、もって
、該抵抗要素に流れる電流の大きさの如何によらず、該
抵抗要素の温度を一定に保持してやることを特徴として
いる。
典型的には、上記抵抗要素に流れる電流による該抵抗要
素の自己加熱量と上記加熱手段による該抵抗要素の外部
加熱量との総和が常に一定となるように、上記抵抗要素
に流れる電流値に応じて、上記加熱手段による該抵抗要
素の外部加熱量を制御してやるものである。
本発明のさらに具体的な構成例においては、以下に示す
二つの手段が講じられている。
第１の手段：
Ｒ工、Ｒ，なる二つの抵抗で電流検出抵抗を構成する。
そして、面抵抗Ｒ１、Ｒ２は、両者間に熱伝導性の良い
絶縁物を介在させてなるべく密着した構造とするなどに
より、両者間に良好な熱的結合状態を保つようにしてお
く。
第２の手段：
いま、抵抗Ｒ１を電流検出用の抵抗（抵抗値Ｒ□）。
抵抗Ｒ２を温度補償用の抵抗（抵抗値Ｒ２）とし、抵抗
Ｒ，，Ｒ，に流れる電流をそれぞれＩ、、Ｉ２で、面抵
抗Ｒ１とＲ２との双方で消費される総電力をＰで表わし
たとき、常に、
Ｐ＝Ｉ□”Ｒ１＋Ｉ、”Ｒ，＝一定 ・・・・・（２
）なる関係を満足するような電流■２を温度補償用抵抗
Ｒ２に流す手段を講じる。
つまり、温度補償用抵抗Ｒ１を、電流検出用抵抗Ｒ１を
外部から加熱するための加熱用ヒーターとして使い、電
流検出用抵抗Ｒ１の温度が常に一定になるように、電流
検出用抵抗Ｒ１に流れる電流１１の値が変化するのに応
じて、温度補償用抵抗Ｒ２に流す電流工、を制御してや
るというものである。なお、外部加熱用ヒーターとして
抵抗素子を使うのは、その方が制御性が良いという理由
による。制御性をある程度犠牲にしてもよい場合には、
いわゆる通常の加熱用ヒーターを用いてもよいことはも
ちろんである。In order to prevent the resistance value of the current detection resistor from changing even if the magnitude of the current flowing through the current detection resistor changes,
Even if the value of the flowing current changes and the power consumption of the current detection resistor changes, it is sufficient to take measures such that the temperature of the current detection resistor does not change. For this purpose, in the present invention, in a current detection device that detects the magnitude of the current by inserting a resistance element in series in a path through which the current flows and detecting the voltage across the resistance element, the resistance element and a means for controlling the amount of heating of the resistance element by the heating means according to the magnitude of the current flowing through the resistance element. Regardless of the temperature, the temperature of the resistance element is kept constant. Typically, the value of the current flowing through the resistance element is set such that the sum of the amount of self-heating of the resistance element due to the current flowing through the resistance element and the amount of external heating of the resistance element by the heating means is always constant. Accordingly, the amount of external heating of the resistance element by the heating means is controlled. In a more specific configuration example of the present invention, the following two measures are taken. First method: Configure a current detection resistor with two resistors R and R. The sheet resistances R1 and R2 are made to have a structure in which they are in close contact with each other as much as possible by interposing an insulator with good thermal conductivity between them, so as to maintain a good thermal bonding state between them. Second means: Now, the resistor R1 is a resistor for current detection (resistance value R□). Let the resistor R2 be a temperature compensation resistor (resistance value R2), the currents flowing through the resistors R, , R, and I2 be respectively, and the total power consumed by both the sheet resistances R1 and R2 be P. When, P=I□"R1+I,"R,=constant...(2
) A means is taken to cause a current (2) that satisfies the following relationship to flow through the temperature compensation resistor R2. In other words, the temperature compensation resistor R1 is used as a heater for heating the current detection resistor R1 from the outside, and the current flowing through the current detection resistor R1 is set such that the temperature of the current detection resistor R1 is always constant. The current flowing through the temperature compensation resistor R2 is controlled in accordance with the change in the value of the temperature compensation resistor R2. Note that the reason why a resistance element is used as an external heater is that it provides better controllability. If you are willing to sacrifice some control,
Of course, a so-called normal heating heater may also be used.
【作用】
このような構成の電流検出装置において、いま、電流検
出用抵抗Ｒ１に流れる偏向電流工、が増加した場合を考
える。この場合、偏向電流■１が増加した分だけ、電流
検出用抵抗Ｒ１で消費される電力は増加するが、これに
対応して、該電流検出用抵抗Ｒ８と熱的に結合されてい
る温度補償用抵抗Ｒ２で消費される電力が逆に減少する
ように、温度補償用抵抗Ｒ２に流す電流値工２が制御さ
れるので、結果として電流検出用抵抗Ｒ，の温度は上昇
しないことになる。すなわち、偏向電流工、が増加して
も、電流検出用抵抗Ｒ１の抵抗値は常に一定に保たれる
という作用効果が得られることになる。
上記とは逆に、偏向電流工、が減少した場合を考える。
この場合には、電流検出用抵抗Ｒ１で消費される電力は
減少するが、その分だけ、温度補償用抵抗Ｒ３で消費さ
れる電力が増加するように、温度補償用抵抗Ｒ３に流す
電流値工、が制御されるので、結果として電流検出用抵
抗Ｒ１の温度は低下しないことになる。
すなわち、本発明の電流検出装置における電流検出抵抗
の構成およびその制御方法によれば、電流検出用抵抗Ｒ
１に流れる被検出電流の大きさの如何に拘らず、電流検
出用抵抗Ｒ□の抵抗値は常に一定に保たれるという作用
効果が得られる。[Operation] In the current detection device having such a configuration, let us now consider the case where the deflection current flowing through the current detection resistor R1 increases. In this case, the power consumed by the current detection resistor R1 increases by the amount that the deflection current ■1 increases, but correspondingly, the temperature compensation that is thermally coupled to the current detection resistor R8 increases. Since the current value 2 flowing through the temperature compensating resistor R2 is controlled so that the power consumed by the resistor R2 decreases, the temperature of the current detecting resistor R does not rise as a result. In other words, even if the deflection current increases, the resistance value of the current detection resistor R1 is always kept constant. Contrary to the above, consider the case where the deflection current is decreased. In this case, although the power consumed by the current detection resistor R1 decreases, the current value applied to the temperature compensation resistor R3 is adjusted so that the power consumed by the temperature compensation resistor R3 increases accordingly. , is controlled, and as a result, the temperature of the current detection resistor R1 does not drop. That is, according to the configuration of the current detection resistor in the current detection device and the control method thereof of the present invention, the current detection resistor R
Regardless of the magnitude of the detected current flowing through the current detection resistor R□, the resistance value of the current detection resistor R□ is always kept constant.
第１図は１本発明を電子線描画装置の偏向アンプに適用
した場合の一実施例を示している。同図において、１は
Ｄ／Ａ変換器、２はアンプ、３は偏向コイルである。４
は本発明になる電流検出装置を構成する電流検出抵抗で
あり、これは互いに熱的に密に結合された二つの抵抗、
すなわち、電流検出用抵抗Ｒ１と温度補償用抵抗Ｒ２と
から構成されている。そして、５は上記電流検出抵抗４
の全消費電力を常に一定に保つための電力制御部であり
、偏向コイル３および電流検出用抵抗Ｒ１に流れる偏向
電流工、の変化に応じて温度補償用抵抗Ｒ３に流す電流
Ｉ２を制御して、電流検出抵抗４全体としての消費電力
Ｐを一定に保持するように動作する。
上記の構成において、入力端子１０に入力されたディジ
タル偏向データＤユは、Ｄ／Ａ変換器１によって、対応
するアナログ偏向電圧Ｖｓに変換される。Ｄ／Ａ変換Ｉ
１１の次段に接続されているアンプ２は、その２人力間
の電圧差がなくなるように動作するものとする。その結
果、電流検出抵抗４の両端間には電圧Ｖｓが印加される
ことになるから、偏向コイル３にはＩ、＝Ｖｓ／Ｒ１な
る偏向電流が流れることとなる。かくして、入力データ
Ｄｉに対応した偏向電流工、が偏向コイル３に流れるこ
とになる。
一方、前述した如く、入力偏向データＤｉ、すなわち、
偏向コイル３に流れる偏向電流工、の変化に従って電流
検出用抵抗Ｒ１の温度ひいてはその抵抗値が変化しよう
とするのを防止し、偏向電流工、の如何に拘らず該電流
検出用抵抗Ｒ１の温度ひいてはその抵抗値が常に一定値
に保持されるように制御するために、入力偏向データＤ
ｉは、電力制御部５にも与えられている。該電力制御部
５は、入力偏向データＤｉの変化（つまり、偏向コイル
３および電流検出用抵抗Ｒ□に流れる偏向電流Ｉｉの変
化）に応じて、温度補償用抵抗Ｒ２に流す電流工２を制
御して該温度補償用抵抗Ｒ２の消費電力を制御して、電
流検出抵抗４全体での総消費電力Ｐを常に一定に保持す
るように動作する。
温度補償用抵抗Ｒ２の消費電力を制御することによって
、電流検出用抵抗Ｒ１の温度を一定に保つだめには、両
抵抗Ｒ１、Ｒ３間の熱伝導特性が良好でなければならな
い。このためには、面抵抗間の電気的絶縁が保たれる限
りにおいて、両抵抗がなるべく密着していることが望ま
しい。
第３図には、電流検出抵抗４のいくつかの代表的な構成
例を示している。第３図（Ａ）は、同じ材質の抵抗体、
例えば、金属抵抗材を使って電流検出用抵抗Ｒ１と温度
補償用抵抗Ｒ２とを作り、両抵抗を熱伝導性の良い絶縁
物７を介して密着させてなる構造例を示している。この
構造は、サンドインチ構造であるため熱伝導性能は非常
に優れているが、いくぶん特殊な構造であるため多少製
作し難いという欠点はある。
第３図（Ｂ）は、抵抗体として巻線抵抗を使った場合の
構成例を示している。すなわち、電気的特性の等しい２
本の巻線抵抗Ｒ，，Ｒ，を、図示のように、ボビン８に
一緒に巻きつけて作製する。このように、両抵抗Ｒ１，
Ｒ２を一緒に巻きつける構造とすると、面抵抗間は比較
的良好な熱伝達特性が得られるが、その構造上からして
インダクタンス成分が大きくなるため、高周波帯域で用
いるのには適さない。
第３図（Ｃ）は、１枚の抵抗基板上に２つの抵抗Ｒユ、
Ｒ２を平面的に構成した場合の例を示している。第３図
（Ａ）の構成例と比べ、平面的に広がっている分だけ熱
伝導特性が若干悪くなるが、製作しやすいという利点が
ある。市販されている一般的なアレー抵抗は、通常この
様な平面的構造になっているので、２素子のアレー抵抗
を利用しても良い。
さて、上記したような構造の電流検出抵抗４を使用した
第１図示の偏向アンプ回路において、電流検出用抵抗Ｒ
１で消費される電力と温度補償用抵抗Ｒ２で消費される
電力との和（全消費電力）Ｐが一定に保たれるための電
流工、と工、との関係は。
前出の（２）式より。
Ｉ、＝ −−Ｉ、 ・・・・・（３
）ただし、Ａ＝Ｐ／Ｒ，、Ｂ＝Ｒ□／Ｒ。
となる。
第１図における電力制御部５は、この（３）式に従って
、温度補償用抵抗Ｒ２に流す電流値Ｉ２の制御を行なう
機能部であり、この部分の詳細な構成例を第４図に示す
、第４図において、１１はメモリー、１２はＤ／Ａ変換
器である。その他の部分については、第１図の場合と同
じであるので、図示を省略しである。ここで、メモリー
１１には。
予め上記（３）式に従って算出された工２値、すなわち
、偏向データ値Ｄｉとそれに対して温度補償のために必
要な電流値工、との関係がストアーされているものとす
る。以下、電力制御部５の動作について説明する。
入力端子１０に、偏向データＤｉが入力されると、それ
に対応した大きさの偏向電流工、が、偏向コイル３およ
び電流検出用抵抗Ｒ１に流されることは、前述した通り
である。一方、偏向データＤｉによってメモリー１１の
対応アドレスが指定されると、この指定アドレスの内容
、つまり、前記（３）式に従って予め計算されて記憶さ
れていた電流値工２のコードデータが、メモリー１１か
ら出力され、この出力データが次段のＤ／Ａ変換器１２
によって、上記電流値工２を流すために必要な電圧値に
変換されて出力される。当然のことながら、この出力電
圧は、両抵抗Ｒ１，Ｒ，によって消費される合計電力を
常に一定とするような電圧値であり、温度補償用抵抗Ｒ
２に所定値の電流工２を流し、両抵抗Ｒ□、Ｒ２の温度
が変化しないような電力を与える。すなわち、このよう
な回路構成とすることによって、電流検出用抵抗Ｒユに
流れる偏向電流工、の大きさが変化し、抵抗Ｒ１自体の
自己発熱量は変化しても、該抵抗Ｒ１の温度、ひいては
、抵抗値の変化は全く生じないので、偏向電流供給□の
変化に関係なく、常に正確な偏向電流供給呂を行なって
、アンプ２を介して正確かつ安定な偏向電流供給を行な
うことが可能になる。
第５図は、電力制御部５の別の構成例を示している。第
５図において、１３．１４はいずれも掛算器、１５はア
ンプ、１６は平方根演算器である。
ここでの電力制御部５の入力側端子は電流検出用抵抗Ｒ
１の電流検出端（電圧出力端）に接続されている。その
他の部分については、第１図の場合と同じであるので、
図示を省略しである。
以下、第５図の回路構成における動作について説明する
。抵抗Ｒ１に流れる電流■、（すなわち、抵抗Ｒ１の両
端間電圧）は、（３）式に従って、掛算器１３で２乗（
Ｌ”）され、さらに、掛算器１４で８倍される。この出
力（Ｂ・工□′）が減算器１１で定数Ａから減算され、
減算結果（Ａ −Ｂ・工、′）が平方根演算器１２で平
方根演算された後、抵抗Ｒ２に所要の電流工２を流すた
めの電圧を与える。
すなわち、これらの回路によって、（３）式に示した演
算が行われることになる。
以上の実施例では、電流検出抵抗４は］個であるものと
して説明してきたが、使用する抵抗体の許容電力の制約
から、複数個の電流検出抵抗を用いることが必要な場合
もある。このような場合には、第６図に示すように、電
流検出用抵抗Ｒ２と温度補償用抵抗Ｒ２とを各グループ
毎にそれぞれ並列接続して用いる。このようにすれば、
見掛は上１つの電流検出抵抗で許容電力が十分に大きい
ものとすることができる。第７図は、同様の目的で、電
流検出用抵抗Ｒ１と温度補償用抵抗Ｒ２とを各グループ
毎にそれぞれ直列接続して用いる場合の実施例を示して
いる。この場合にも前記と同じように、見掛は上１つの
電流検出抵抗とすることができる。しかし、あまりにも
抵抗体の数が増えてくると、従来技術の項で述べたのと
同様な問題が新たに生じてくるという難点は避けられな
いことである。
電流検出抵抗４における電流検出用抵抗Ｒ□と温度補償
用抵抗Ｒ２とは、両者間の熱伝導性を良くしたいという
観点から、１枚の抵抗基板上に構成されることが望まし
いが、市販されている一般的な形状の抵抗体であっても
、例えば第８図に示すように、抵抗体同志を密着させて
配置した上で、上述した本発明による電力制御方法を適
用すれば、何も対策しない場合に比べ、電流検出用抵抗
Ｒ１の抵抗変化をより少なくすることが可能になる。
複数個の電流検出抵抗を使う場合にも、上記と同様に抵
抗体同志を密着配置して用いるのが有効であるが、この
ような場合には、さらに、電流検出用抵抗Ｒ１と温度補
償用抵抗Ｒ２とが交互に並ぶように配列すれば、その分
さらに熱伝導性が良くなり、抵抗値の温度補償効果がよ
り良好となる。FIG. 1 shows an embodiment in which the present invention is applied to a deflection amplifier for an electron beam lithography system. In the figure, 1 is a D/A converter, 2 is an amplifier, and 3 is a deflection coil. 4
is a current detection resistor constituting the current detection device according to the present invention, which consists of two resistors that are thermally closely coupled to each other,
That is, it is composed of a current detection resistor R1 and a temperature compensation resistor R2. 5 is the current detection resistor 4
This is a power control unit for keeping the total power consumption constant at all times, and controls the current I2 flowing through the temperature compensation resistor R3 according to changes in the deflection current flowing through the deflection coil 3 and the current detection resistor R1. , operates so as to keep the power consumption P of the current detection resistor 4 as a whole constant. In the above configuration, the digital deflection data D input to the input terminal 10 is converted by the D/A converter 1 into a corresponding analog deflection voltage Vs. D/A conversion I
It is assumed that the amplifier 2 connected to the next stage of the amplifier 11 operates so as to eliminate the voltage difference between the two amplifiers. As a result, the voltage Vs is applied between both ends of the current detection resistor 4, so that a deflection current I,=Vs/R1 flows through the deflection coil 3. Thus, a deflection current corresponding to the input data Di flows through the deflection coil 3. On the other hand, as mentioned above, the input deflection data Di, that is,
This prevents the temperature of the current detection resistor R1 and its resistance value from changing according to changes in the deflection current flowing through the deflection coil 3, and prevents the temperature of the current detection resistor R1 from changing regardless of the deflection current. Furthermore, in order to control the resistance value so that it is always kept at a constant value, the input deflection data D
i is also given to the power control section 5. The power control unit 5 controls the electric current 2 flowing through the temperature compensation resistor R2 in accordance with the change in the input deflection data Di (that is, the change in the deflection current Ii flowing through the deflection coil 3 and the current detection resistor R□). The power consumption of the temperature compensation resistor R2 is controlled so that the total power consumption P of the current detection resistor 4 as a whole is always kept constant. In order to keep the temperature of the current detection resistor R1 constant by controlling the power consumption of the temperature compensation resistor R2, the heat conduction characteristics between the resistors R1 and R3 must be good. For this purpose, it is desirable that the two resistors be in close contact with each other as much as possible as long as electrical insulation between the sheet resistors is maintained. FIG. 3 shows some typical configuration examples of the current detection resistor 4. Figure 3 (A) shows resistors made of the same material,
For example, an example of a structure is shown in which the current detection resistor R1 and the temperature compensation resistor R2 are made of a metal resistance material, and both resistors are brought into close contact with each other via an insulator 7 with good thermal conductivity. Since this structure is a sandwich inch structure, it has very good heat conduction performance, but it has the disadvantage that it is somewhat difficult to manufacture because it has a somewhat special structure. FIG. 3(B) shows a configuration example in which a wire-wound resistor is used as the resistor. That is, two with equal electrical characteristics
The wire-wound resistors R, , R, are made by winding them together around the bobbin 8 as shown in the figure. In this way, both resistors R1,
If R2 is wound together, relatively good heat transfer characteristics can be obtained between the sheet resistances, but the inductance component becomes large due to the structure, so it is not suitable for use in a high frequency band. Figure 3(C) shows two resistors R on one resistor board.
An example is shown in which R2 is configured in a planar manner. Compared to the configuration example shown in FIG. 3(A), the heat conduction characteristics are slightly worse due to the planar spread, but it has the advantage of being easier to manufacture. Since commercially available general array resistors usually have such a planar structure, a two-element array resistor may be used. Now, in the deflection amplifier circuit shown in FIG. 1 using the current detection resistor 4 having the structure described above, the current detection resistor R
What is the relationship between current factor and factor in order to keep the sum (total power consumption) P of the power consumed by R1 and the power consumed by temperature compensation resistor R2 constant? From equation (2) above. I, = −I, ......(3
) However, A=P/R, B=R□/R. becomes. The power control unit 5 in FIG. 1 is a functional unit that controls the current value I2 flowing through the temperature compensation resistor R2 according to equation (3), and a detailed configuration example of this part is shown in FIG. In FIG. 4, 11 is a memory, and 12 is a D/A converter. The other parts are the same as those shown in FIG. 1, so illustration is omitted. Here, in memory 11. It is assumed that the relationship between the deflection data value Di calculated according to the above equation (3), that is, the deflection data value Di and the current value required for temperature compensation with respect to it, is stored in advance. The operation of the power control section 5 will be explained below. As described above, when the deflection data Di is input to the input terminal 10, a deflection current having a corresponding magnitude is applied to the deflection coil 3 and the current detection resistor R1. On the other hand, when the corresponding address in the memory 11 is designated by the deflection data Di, the content of this designated address, that is, the code data of the current value controller 2 that has been calculated and stored in advance according to the formula (3) above, is transferred to the memory 11. This output data is sent to the next stage D/A converter 12.
The current value is converted into a voltage value necessary for flowing the current value generator 2 and output. Naturally, this output voltage is such that the total power consumed by both resistors R1 and R is always constant, and the temperature compensation resistor R
A current of a predetermined value is applied to the resistors R□ and R2 so that the temperature of both resistors R□ and R2 does not change. That is, with such a circuit configuration, even if the magnitude of the deflection current flowing through the current detection resistor R changes and the amount of self-heating of the resistor R1 itself changes, the temperature of the resistor R1, Furthermore, since there is no change in resistance value, it is possible to always provide an accurate deflection current supply regardless of changes in the deflection current supply □, and to provide an accurate and stable deflection current supply via the amplifier 2. become. FIG. 5 shows another configuration example of the power control section 5. In FIG. In FIG. 5, 13 and 14 are multipliers, 15 is an amplifier, and 16 is a square root calculator. The input side terminal of the power control unit 5 here is a current detection resistor R
It is connected to the current detection terminal (voltage output terminal) of No. 1. The other parts are the same as in Figure 1, so
Illustrations are omitted. The operation of the circuit configuration shown in FIG. 5 will be described below. The current ■ flowing through the resistor R1 (that is, the voltage across the resistor R1) is squared by the multiplier 13 according to equation (3).
L'') and then multiplied by 8 in the multiplier 14. This output (B・d') is subtracted from the constant A in the subtracter 11,
After the subtraction result (A-B·E,') is subjected to a square root operation in the square root operator 12, a voltage for causing the required current 2 to flow is applied to the resistor R2. That is, these circuits perform the calculation shown in equation (3). In the above embodiments, the number of current detection resistors 4 has been described as being [], but due to restrictions on the allowable power of the resistor used, it may be necessary to use a plurality of current detection resistors. In such a case, as shown in FIG. 6, a current detection resistor R2 and a temperature compensation resistor R2 are connected in parallel for each group. If you do this,
Apparently, the allowable power can be made sufficiently large with just one current detection resistor. FIG. 7 shows an embodiment in which a current detection resistor R1 and a temperature compensation resistor R2 are connected in series for each group and used for the same purpose. In this case, as in the above case, the appearance can be made to be one current detection resistor. However, if the number of resistors increases too much, problems similar to those described in the prior art section will inevitably arise. It is desirable that the current detection resistor R□ and the temperature compensation resistor R2 in the current detection resistor 4 be constructed on one resistor board from the viewpoint of improving the thermal conductivity between them. Even if the resistor has a general shape, for example, as shown in FIG. 8, if the resistors are placed closely together and the power control method according to the present invention described above is applied, nothing Compared to the case where no countermeasure is taken, it becomes possible to further reduce the change in resistance of the current detection resistor R1. When using multiple current detection resistors, it is effective to arrange the resistors closely together in the same way as above, but in such a case, it is also effective to arrange the resistors R1 for current detection and for temperature compensation. If the resistors R2 are arranged alternately, the thermal conductivity will be further improved, and the temperature compensation effect of the resistance value will be better.
以上詳述した如く、本発明の電流検出装置構成によれば
、電流検出用抵抗にながれる電流の大きさが変化しても
、該電流検出用抵抗の温度は常に一定に保たれるため、
該電流検出用抵抗の抵抗値変化は生じない。したがって
、正確かつ安定な電流検出が可能となる。As detailed above, according to the current detection device configuration of the present invention, even if the magnitude of the current flowing through the current detection resistor changes, the temperature of the current detection resistor is always kept constant.
The resistance value of the current detection resistor does not change. Therefore, accurate and stable current detection is possible.
第１図は、本発明による電流検出装置を組み込んでなる
偏向アンプの基本的回路構成図。
第２図は、従来一般の偏向アンプの基本的回路構成図。
第３図は、本発明による電流検出抵抗の構成例を示す概
略構造図。
第４図および第５図は、それぞれ、第１図における電力
制御部の詳細構成例を示す回路図。
第６図、第７図および第８図は、それぞれ、本発明によ
る電流検出抵抗の他の構成例を示す模式％式％
：
：
：
：
：
：
：
：FIG. 1 is a basic circuit configuration diagram of a deflection amplifier incorporating a current detection device according to the present invention. FIG. 2 is a basic circuit configuration diagram of a conventional general deflection amplifier. FIG. 3 is a schematic structural diagram showing a configuration example of a current detection resistor according to the present invention. 4 and 5 are circuit diagrams showing detailed configuration examples of the power control section in FIG. 1, respectively. 6, 7, and 8 are schematic % formulas showing other configuration examples of the current detection resistor according to the present invention, respectively.
Claims (12)
抗要素の両端間電圧を検出して、上記電流の大きさを検
知する電流検出装置において、上記抵抗要素を加熱する
手段を付設し、かつ、該抵抗要素に流れる電流の大きさ
に応じて、上記加熱手段による該抵抗要素の加熱量を制
御する手段を付設してなることを特徴とする電流検出装
置。1. A current detection device that detects the magnitude of the current by inserting a resistance element in series in a path through which a current flows and detecting the voltage across the resistance element, the current detection device including means for heating the resistance element, and . A current detection device, comprising: means for controlling the amount of heating of the resistance element by the heating means according to the magnitude of the current flowing through the resistance element.
抗要素の両端間電圧を検出して、上記電流の大きさを検
知する電流検出装置において、上記抵抗要素を加熱する
手段と、該抵抗要素に流れる電流の大きさに応じて、上
記加熱手段による該抵抗要素の加熱量を制御する手段と
を付設し、もって、該抵抗要素に流れる電流の大きさに
拘らず、該抵抗要素の温度を一定に保持してなることを
特徴とする電流検出装置。2. A current detection device that detects the magnitude of the current by inserting a resistance element in series in a path through which a current flows and detecting the voltage across the resistance element, comprising means for heating the resistance element; means for controlling the amount of heating of the resistance element by the heating means according to the magnitude of the current flowing through the resistance element, thereby controlling the temperature of the resistance element regardless of the magnitude of the current flowing through the resistance element. A current detection device characterized by being kept constant.
両端間電圧を検出して、該検出電圧と上記抵抗要素の抵
抗値とから、上記電流通路に流れる電流値を求める電流
検出装置において、上記抵抗要素を加熱する手段を設け
、かつ、該抵抗要素に流れる電流値の変化に応じて、上
記抵抗要素加熱手段による該抵抗要素の加熱量を制御す
る手段を付設し、もって、該抵抗要素に流れる電流値の
変化に拘らず、該抵抗要素の温度を一定に保持してなる
ことを特徴とする電流検出装置。3. A current detection device in which a resistance element is inserted in series in a current path, a voltage across the resistance element is detected, and a current value flowing in the current path is determined from the detected voltage and a resistance value of the resistance element. A means for heating the resistance element is provided, and a means for controlling the amount of heating of the resistance element by the resistance element heating means according to a change in the value of the current flowing through the resistance element is provided. A current detection device characterized in that the temperature of the resistance element is kept constant regardless of changes in the value of the current flowing through the current detection device.
検出用抵抗の両端間電圧を検出して、上記電流通路に流
れる電流値を検知する電流検出装置において、上記電流
検出用抵抗の近傍に該電流検出用抵抗と熱伝導状態に保
たれた温度補償用抵抗を付設し、かつ、該温度補償用抵
抗に温度補償用の電流を流す手段を付設し、さらに、上
記電流検出用抵抗に流れる電流値に応じて、上記１度補
償用抵抗に流すべき１度補償用電流の電流値を制御する
手段を付設してなることを特徴とする電流検出装置。4. In a current detection device that inserts a current detection resistor in series in a current path, detects the voltage across the current detection resistor, and detects the value of the current flowing in the current path, the current detection resistor is connected in the vicinity of the current detection resistor. A temperature compensation resistor that is maintained in a thermally conductive state with the current detection resistor is attached, and a means is attached for causing a temperature compensation current to flow through the temperature compensation resistor, and further, a temperature compensation resistor is provided that causes a temperature compensation current to flow through the current detection resistor. A current detection device characterized in that it is provided with means for controlling the current value of the one-time compensation current to be passed through the one-time compensation resistor according to the current value.
の電流値を制御する手段は、上記電流検出用抵抗によっ
て消費される電力と上記温度補償用抵抗によって消費さ
れる電力との総和が一定となるように、上記温度補償用
電流の電流値を制御するものであることを特徴とする請
求項４記載の電流検出装置。5. The means for controlling the current value of the temperature compensation current to be passed through the temperature compensation resistor is such that the sum of the power consumed by the current detection resistor and the power consumed by the temperature compensation resistor is constant. 5. The current detection device according to claim 4, wherein the current value of the temperature compensation current is controlled in such a manner.
、互いに同一の抵抗基板上に設けられている金属抵抗で
あることを特徴とする請求項４または５記載の電流検出
装置。6. 6. The current detecting device according to claim 4, wherein the current detecting resistor and the temperature compensating resistor are metal resistors provided on the same resistor substrate.
、互いに同一の基体上に捲設されている巻線抵抗である
ことを特徴とする請求項４または５記載の電流検出装置
。7. 6. The current detecting device according to claim 4, wherein the current detecting resistor and the temperature compensating resistor are wire-wound resistors wound on the same base.
、互いに密着して配置されているものであることを特徴
とする請求項４または５記載の電流検出装置。8. 6. The current detecting device according to claim 4, wherein the current detecting resistor and the temperature compensating resistor are arranged in close contact with each other.
検出用抵抗の両端間電圧を検出して、上記電流通路に流
れる電流値を検知する電流検出装置において、上記電流
検出用抵抗の近傍に該電流検出用抵抗と熱伝導状態に保
たれた温度補償用の発熱体を付設し、かつ、上記電流検
出用抵抗に流れる電流値に応じて、上記温度補償用発熱
体の発熱量を制御する手段を付設してなることを特徴と
する電流検出装置。9. In a current detection device that inserts a current detection resistor in series in a current path, detects the voltage across the current detection resistor, and detects the value of the current flowing in the current path, the current detection resistor is connected in the vicinity of the current detection resistor. A heating element for temperature compensation maintained in a thermally conductive state with the current detection resistor is attached, and the amount of heat generated by the temperature compensation heating element is controlled in accordance with the value of the current flowing through the current detection resistor. A current detection device characterized by being provided with means.
段は、上記電流検出用抵抗の発熱量と上記温度補償用発
熱体の発熱量との総和が一定となるように、上記温度補
償用発熱体の発熱量を制御するものであることを特徴と
する請求項９記載の電流検出装置。10. The means for controlling the amount of heat generated by the heating element for temperature compensation is configured to control the amount of heat generated by the heating element for temperature compensation so that the sum of the amount of heat generated by the current detection resistor and the amount of heat generated by the temperature compensation heating element becomes constant. 10. The current detecting device according to claim 9, wherein the current detecting device controls the amount of heat generated by the current detecting device.
置を用いて偏向コイルに流れる偏向電流を検出し、該偏
向電流の負帰還制御を行なうように構成してなることを
特徴とする偏向コイル駆動用回路。11. A deflection coil drive, characterized in that it is configured to detect a deflection current flowing through the deflection coil using the current detection device according to any one of claims 1 to 10, and perform negative feedback control of the deflection current. circuit.
荷電粒子線応用装置。12. A charged particle beam application device using the deflection coil driving circuit according to claim 11.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16265390A JPH0454458A (en) | 1990-06-22 | 1990-06-22 | Current detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16265390A JPH0454458A (en) | 1990-06-22 | 1990-06-22 | Current detector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0454458A true JPH0454458A (en) | 1992-02-21 |
Family
ID=15758717
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16265390A Pending JPH0454458A (en) | 1990-06-22 | 1990-06-22 | Current detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0454458A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009003395A1 (en) * | 2007-06-29 | 2009-01-08 | Wei Wu | A wide range and high accuracy on-line current and temperature measuring device and method |
| JP2011029068A (en) * | 2009-07-28 | 2011-02-10 | Shimadzu Corp | Current feedback type power source and charged particle beam device |
| JP2014196931A (en) * | 2013-03-29 | 2014-10-16 | 住友重機械工業株式会社 | Charge/discharge inspection system, and calibration device of charge/discharge inspection device and calibration method thereof |
| CN109521252A (en) * | 2018-11-27 | 2019-03-26 | 北京智芯微电子科技有限公司 | The detection device of DC leakage current |
| JPWO2020003841A1 (en) * | 2018-06-27 | 2021-08-12 | ヌヴォトンテクノロジージャパン株式会社 | Battery monitoring device, integrated circuit, and battery monitoring system |
-
1990
- 1990-06-22 JP JP16265390A patent/JPH0454458A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009003395A1 (en) * | 2007-06-29 | 2009-01-08 | Wei Wu | A wide range and high accuracy on-line current and temperature measuring device and method |
| JP2011029068A (en) * | 2009-07-28 | 2011-02-10 | Shimadzu Corp | Current feedback type power source and charged particle beam device |
| JP2014196931A (en) * | 2013-03-29 | 2014-10-16 | 住友重機械工業株式会社 | Charge/discharge inspection system, and calibration device of charge/discharge inspection device and calibration method thereof |
| JPWO2020003841A1 (en) * | 2018-06-27 | 2021-08-12 | ヌヴォトンテクノロジージャパン株式会社 | Battery monitoring device, integrated circuit, and battery monitoring system |
| CN109521252A (en) * | 2018-11-27 | 2019-03-26 | 北京智芯微电子科技有限公司 | The detection device of DC leakage current |
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