JPH0534581U - Power supply abnormality detection circuit - Google Patents

Power supply abnormality detection circuit

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Publication number
JPH0534581U
JPH0534581U JP10705091U JP10705091U JPH0534581U JP H0534581 U JPH0534581 U JP H0534581U JP 10705091 U JP10705091 U JP 10705091U JP 10705091 U JP10705091 U JP 10705091U JP H0534581 U JPH0534581 U JP H0534581U
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JP
Japan
Prior art keywords
power supply
abnormality detection
resistance
transistor
detection circuit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP10705091U
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Japanese (ja)
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JP2580932Y2 (en
Inventor
幸男 高橋
秀雄 武田
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Yokogawa Electric Corp
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Yokogawa Electric Corp
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Priority to JP10705091U priority Critical patent/JP2580932Y2/en
Publication of JPH0534581U publication Critical patent/JPH0534581U/en
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Publication of JP2580932Y2 publication Critical patent/JP2580932Y2/en
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  • Measurement Of Current Or Voltage (AREA)
  • Testing Electric Properties And Detecting Electric Faults (AREA)
  • Emergency Protection Circuit Devices (AREA)

Abstract

(57)【要約】 【目的】 多数の電源の一つに異常が発生した場合で
も、精度良く電源の異常を検出する。 【構成】 それぞれ異なった電圧(V1,V2,…Vn )を
出力するn個の電源の異常を検出する電源異常検出回路
であって、電源中で最大の電圧V1 を出力する電源と共
通電位点との間に直列に設けられた(n+1)個の抵抗
と、i番目(i=1〜n)の抵抗と(i+1)番目の抵
抗の共通接続点と電圧(Vi )を出力する電源間に接続
したダイオ−ド(Di )と、共通電位点に接続された
(n+1)番目の抵抗とn番目の抵抗との共通接続点に
ベ−スが接続され、エミッタが共通電位点に接続された
トランジスタ(1)と、を設け、コレクタ出力から電源
の故障を検出するようにしている。
(57) [Summary] [Purpose] Even if one of a large number of power supplies fails, the power supply can be detected accurately. [Structure] A power supply abnormality detection circuit for detecting abnormality of n power supplies which respectively output different voltages (V1, V2, ... Vn), the power supply outputting a maximum voltage V1 among the power supplies and a common potential point Between (n + 1) resistances, a common connection point of the i-th (i = 1 to n) resistance and the (i + 1) -th resistance, and a power supply that outputs a voltage (Vi). The base was connected to the common connection point of the connected diode (Di) and the (n + 1) th resistance and the nth resistance connected to the common potential point, and the emitter was connected to the common potential point. A transistor (1) is provided to detect a power supply failure from the collector output.

Description

【考案の詳細な説明】[Detailed description of the device]

【0001】[0001]

【産業上の利用分野】[Industrial applications]

本考案は、電源の異常を検出する電源異常検出回路に関し、更に詳しくは、複 数の異なった電圧Vn を有する電源が設けられた電気回路において、いずれかの 電源に異常が発生しても精度良く電源の異常を検出することができる電源異常検 出回路に関する。 The present invention relates to a power supply abnormality detection circuit for detecting a power supply abnormality. More specifically, in an electric circuit provided with a power supply having a plurality of different voltages Vn, even if one of the power supplies fails, the accuracy is improved. The present invention relates to a power supply abnormality detection circuit capable of well detecting a power supply abnormality.

【0002】[0002]

【従来の技術】[Prior Art]

図3は、従来の電源異常検出回路の回路図である。図中、1はNPNのトラン ジスタで、コレクタが抵抗R10を介して正の電源+Vccに接続され、エミッタが 共通電位点に接続されている。 FIG. 3 is a circuit diagram of a conventional power supply abnormality detection circuit. In the figure, 1 is an NPN transistor, the collector of which is connected to a positive power source + Vcc through a resistor R10 and the emitter of which is connected to a common potential point.

【0003】 R11〜R13は一端がトランジスタ1のベ−スに接続され、他端が電源V1 〜V 3 に接続された抵抗で、抵抗R11、R12、R13にはそれぞれ電流I11、I12、I 13が流れる。R14はトランジスタ1のベ−スと共通電位点に設けられた抵抗であ る。 電源V1 〜V3 によって各抵抗R11〜R13に電流I11〜I13が流れると、トラ ンジスタ1のベ−スにはベ−ス電流IB が流れ、抵抗R14には残りの電流I14が 流れる。R11 to R13 are resistors having one ends connected to the base of the transistor 1 and the other ends connected to the power sources V1 to V3. The resistors R11, R12 and R13 have currents I11, I12 and I13, respectively. Flows. R14 is a resistor provided at the common potential point with the base of the transistor 1. When the currents I11 to I13 flow through the resistors R11 to R13 by the power sources V1 to V3, the base current IB flows through the base of the transistor 1 and the remaining current I14 flows through the resistor R14.

【0004】 抵抗R14に電流I14が流れ、抵抗R14の電圧降下がベ−ス−エミッタ電圧VBE 以上になると、トランジスタ1は、オンとなり、出力端子V0 は各電源V1 〜V 3 が正常に動作している状態を示すロ−レベル信号を出力する。 しかし、電源V1 が故障したような場合、抵抗R4 に流れる電流I14は、I12 +I13−IB となり、抵抗R14における電圧降下は、トランジスタ1をオンする ことができるベ−ス−エミッタ電圧VBEに達しないため、出力端子V0 はフェイ ル信号であるハイレベル状態に反転する。When the current I14 flows through the resistor R14 and the voltage drop across the resistor R14 becomes equal to or higher than the base-emitter voltage VBE, the transistor 1 is turned on, and the power supply V1 to V3 operates normally at the output terminal V0. A low level signal indicating that the state is in progress. However, when the power source V1 fails, the current I14 flowing through the resistor R4 becomes I12 + I13-IB, and the voltage drop at the resistor R14 does not reach the base-emitter voltage VBE that can turn on the transistor 1. Therefore, the output terminal V0 is inverted to a high level state which is a fail signal.

【0005】[0005]

【考案が解決しようとする課題】[Problems to be solved by the device]

このような従来の電源異常検出回路は、トランジスタに接続される電源の数が 増えるにしたがって、各電源から各抵抗に流れる電流を小さな値にしなければな らないため、一つの電源に故障があっても抵抗R14を流れる電流I14の変化が小 さくなるため、電源の故障を正確に検出できないということがあった。 In such a conventional power supply abnormality detection circuit, as the number of power supplies connected to the transistors increases, the current flowing from each power supply to each resistance must be made a small value, so there is a failure in one power supply. However, since the change in the current I14 flowing through the resistor R14 is small, the failure of the power supply may not be accurately detected.

【0006】 本考案は、このような点に鑑みてなされたもので、回路中の電源の数が増えて も正確に各電源の動作を監視することができるようにしたもので、多数の電源の 一つに異常が発生した場合でも、精度良く電源の異常を検出することができる電 源異常検出回路を提供することを目的としている。The present invention has been made in view of the above circumstances, and is designed to enable accurate monitoring of the operation of each power supply even when the number of power supplies in the circuit is increased. It is an object of the present invention to provide a power supply abnormality detection circuit that can detect a power supply abnormality with high accuracy even if one of them occurs.

【0007】[0007]

【課題を解決するための手段】[Means for Solving the Problems]

それぞれ異なった電圧(V1,V2,…Vn )を出力するn個の電源の異常を検出 する電源異常検出回路であって、 前記電源中で最大の電圧V1 を出力する電源と共通電位点との間に直列に設け られた(n+1)個の抵抗と、 i番目(i=1〜n)の抵抗と(i+1)番目の抵抗の共通接続点と前記電圧 (Vi )を出力する電源間に接続したダイオ−ド(Di )と、 共通電位点に接続された(n+1)番目の抵抗とn番目の抵抗との共通接続点 にベ−スが接続され、エミッタが共通電位点に接続されたトランジスタ(1)と 、 を設け、いずれかの電源に故障が発生した時、前記トランジスタ(1)のコ レクタ出力から前記電源の故障を検出するようにしたことを特徴としている。 A power supply abnormality detection circuit for detecting abnormality of n power supplies which respectively output different voltages (V1, V2, ... Vn). The power supply outputs the maximum voltage V1 among the power supplies and a common potential point. Connected between (n + 1) resistances connected in series, a common connection point of the i-th (i = 1 to n) resistance and the (i + 1) th resistance, and the power supply that outputs the voltage (Vi). A transistor whose base is connected to the common connection point of the diode (Di) and the (n + 1) th resistance and the nth resistance which are connected to the common potential point and whose emitter is connected to the common potential point. (1) and (1) are provided, and when a failure occurs in any of the power supplies, the failure of the power supply is detected from the collector output of the transistor (1).

【0008】[0008]

【作用】[Action]

電源中で最大の電圧を有する電源と共通電位点との間に直列接続された(n+ 1)個の抵抗の各分圧点には、分圧電圧より大きな電圧の電源が接続され、共通 電位点に接続された抵抗の分圧点にはトランジスタのベ−スが接続されている。 各電源が正常な場合は、最大の電圧を有する電源からの電流によってトランジ スタはオンしていて、電源のいずれかに異常が発生するとトランジスタはオフさ れ、トランジスタのコレクタ出力から電源の故障が検知される。 A power source having a voltage higher than the divided voltage is connected to each of the voltage dividing points of the (n + 1) resistors connected in series between the power source having the maximum voltage in the power source and the common potential point, and the common potential is The base of the transistor is connected to the voltage dividing point of the resistor connected to the point. When each power supply is normal, the transistor is turned on by the current from the power supply with the maximum voltage, and if an abnormality occurs in any of the power supplies, the transistor is turned off, and the power supply fails from the collector output of the transistor. Detected.

【0009】[0009]

【実施例】【Example】

以下、図面を用いて本考案の一実施例を詳細に説明する。図1は、本考案の電 源異常検出回路の一実施例を示す回路図である。尚、本実施例では、回路中の電 源が3個の場合を例に挙げて説明してあるが、更に個数が増えたような場合でも 動作は同じで、異なることはない。 図中、1はNPNのトランジスタで、コレクタが抵抗R10を介して正の電源+ Vccに接続され、エミッタが共通電位点に接続されている。 V1 〜V3 は異なった電圧Vを有する電源で、それぞれの電圧値はV1 >V2 >V3 の関係になっている。 An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a circuit diagram showing an embodiment of the power supply abnormality detection circuit of the present invention. In the present embodiment, the case where the number of power sources in the circuit is three has been described as an example, but the operation is the same even when the number of power sources is further increased, and there is no difference. In the figure, 1 is an NPN transistor, the collector of which is connected to a positive power source + Vcc through a resistor R10 and the emitter of which is connected to a common potential point. V1 to V3 are power supplies having different voltages V, and the respective voltage values have a relationship of V1> V2> V3.

【0010】 R1 〜R4 は電源中V1 〜V3 で最大の電圧値を有する電源V1 と共通電位点 との間に直列に接続された抵抗で、抵抗R1 と抵抗R2 の接続点aは、逆極性の ダイオ−ドD1 を介して電源V2 に接続され、抵抗R2 と抵抗R3 の接続点bは 、逆極性のダイオ−ドD2 を介して電源V3 に接続されている。 そして、抵抗R3 と抵抗R4 の接続点cは、トランジスタ1のベ−スに接続さ れている。R1 to R4 are resistors connected in series between the power source V1 having the maximum voltage value in the power sources V1 to V3 and the common potential point, and the connection point a of the resistors R1 and R2 has a reverse polarity. Is connected to the power source V2 via the diode D1 and the connection point b between the resistors R2 and R3 is connected to the power source V3 via the opposite polarity diode D2. The connection point c between the resistors R3 and R4 is connected to the base of the transistor 1.

【0011】 尚、接続点aの電位V2*は、電源V2 よりも低く、接続点bの電位V3*は、電 源V3 よりも低くなるように、抵抗R1 〜R3 によって設定されている。The potential V2 * at the connection point a is set lower than the power supply V2, and the potential V3 * at the connection point b is set lower than the power supply V3 by the resistors R1 to R3.

【0012】 次にこのように構成された電源異常検出回路の動作を説明する。 各電源が正常な場合 ダイオ−ドD1,2 は逆バイアスになっているので、電源V2,3 側から電流が抵 抗R1 〜R4 に流れ込むことも、電源V1 による電流I1 が電源V2,3 に流れ込 むこともない。Next, the operation of the power supply abnormality detection circuit configured as described above will be described. When each power supply is normal, the diodes D1,2 are reverse biased, so current may flow from the power supply V2,3 side to the resistors R1 to R4, or the current I1 from the power supply V1 may flow to the power supply V2,3. It doesn't flow.

【0013】 すなわち正常時は、電源V1 からの電流I1 のみがトランジスタ1のベ−スと 抵抗R4 に流れるようになっている。この時、トランジスタ1のベ−スにはベ− ス電流IB が流れ、抵抗R4 には残りの電流I4 、すなわちI1 −IB が流れる 。That is, under normal conditions, only the current I1 from the power source V1 flows through the base of the transistor 1 and the resistor R4. At this time, the base current IB flows through the base of the transistor 1, and the remaining current I4, that is, I1-IB flows through the resistor R4.

【0014】 抵抗R4 に流れた電流I4 によって、トランジスタ1はオンとなり、コレクタ の出力端子V0 は各電源V1 〜V3 が正常に動作している状態を示すロ−レベル 信号を出力する。The transistor 1 is turned on by the current I4 flowing through the resistor R4, and the output terminal V0 of the collector outputs a low level signal indicating that the power sources V1 to V3 are operating normally.

【0015】 いずれかの電源に異常が発生した場合 例えば、電源V2 に異常が発生したような場合、電源V2 と接続点aの電圧の 関係がV2*>V2 に反転し、ダイオ−ドD1 は順バイアスになる。この為、電源 V1 の電流I1 は、電源V2 に向かって流れ込み、抵抗R4 に流れる電流I4 は ゼロになる。 トランジスタ1は、抵抗R4 に流れる電流I4 がゼロになるためにオフとなり 、出力端子V0 は、フェイル信号であるハイレベル信号に反転する。When an abnormality occurs in any of the power supplies, for example, when an abnormality occurs in the power supply V2, the relation between the voltage of the power supply V2 and the voltage at the connection point a is inverted to V2 *> V2, and the diode D1 is It becomes a forward bias. Therefore, the current I1 of the power source V1 flows toward the power source V2, and the current I4 of the resistor R4 becomes zero. The transistor 1 is turned off because the current I4 flowing through the resistor R4 becomes zero, and the output terminal V0 is inverted to a high level signal which is a fail signal.

【0016】 図2は、本考案の電源異常検出回路の他の実施例を示した回路図である。正の 電源が設けられている回路は先に説明した実施例と同様なので、ここでは負の電 源が設けられた回路についてのみ説明する。FIG. 2 is a circuit diagram showing another embodiment of the power supply abnormality detection circuit of the present invention. Since the circuit provided with the positive power source is the same as that of the above-described embodiment, only the circuit provided with the negative power source will be described here.

【0017】 2はPNPのトランジスタで、エミッタがトランジスタ1のエミッタに接続さ れ、コレクタが共通電位点に接続されている。 −V1〜−V3は負の電源、R1-〜R4-は電源−V1と抵抗R4との間に直列に接 続された抵抗で、抵抗R4と抵抗R4-の接続点が共通電位点に接続されている。 接続点a-はダイオードD1-を介して電源V2-に接続され、接続点b-はダイオー ドD2-を介して電源V3-に接続されている。接続点a-及びb-は、接続された電源 電圧−V2、−V3より、高い電位に設定されていて、各ダイオードD1-、D2-は、 共に逆バイアスになっている。 一方、抵抗R3-〜R4‐の接続点c-は、トランジスタ2のベースに接続される 。A PNP transistor 2 has an emitter connected to the emitter of the transistor 1 and a collector connected to a common potential point. -V1 to -V3 are negative power supplies, R1- to R4- are resistors connected in series between power supply -V1 and resistor R4, and the connection point of resistors R4 and R4- is connected to the common potential point. Has been done. The connection point a- is connected to the power supply V2- via the diode D1-, and the connection point b- is connected to the power supply V3- via the diode D2-. The connection points a- and b- are set to a potential higher than the connected power supply voltages -V2 and -V3, and the diodes D1- and D2- are both reverse biased. On the other hand, the connection point c- of the resistors R3--R4- is connected to the base of the transistor 2.

【0018】 次に、このように構成された電源異常検出回路において、電源−V2に故障が 発生した場合を例に挙げて説明する。 尚、各電源が正常な場合、電流I1、I1-は以下に示す関係になっていて、トラ ンジスタ1、2は、共にオンとなっている。 I1=I4+IB I1-=I4-+IB- 電源−V2が故障すると、接続点a-と電源−V2の電圧の関係が−V2*<−V2 に反転し、ダイオードD1-は、順バイアスになる。この為、電流は、−V2から− V1に流れ、抵抗R4-に流れる電流I4-はゼロになり、トランジスタ1、2はオ フとなる。 よって、出力端子V0は、フェイル信号であるハイレベルに反転する。Next, a case where a failure occurs in the power supply −V2 in the power supply abnormality detection circuit configured as described above will be described as an example. When each power supply is normal, the currents I1 and I1- have the following relationships, and the transistors 1 and 2 are both on. I1 = I4 + IB I1- = I4- + IB- When the power supply -V2 fails, the relationship between the voltage at the connection point a- and the power supply -V2 is inverted to -V2 * <-V2, and the diode D1- becomes forward biased. Therefore, the current flows from -V2 to -V1, the current I4- flowing through the resistor R4- becomes zero, and the transistors 1 and 2 are turned off. Therefore, the output terminal V0 is inverted to a high level which is a fail signal.

【0019】[0019]

【考案の効果】[Effect of the device]

以上、詳細に説明したように本考案の電源異常検出回路は、故障を警告するト ランジスタの駆動を、常に、一つ電源のみによって行っているためトランジスタ のオン/オフを精度良く行うことができるので、電源の数を任意に増やしても電 源の故障の管理が正確に行うことができる。また、このため、トランジスタのベ −ス−エミッタ電圧のバラツキや温度特性も考慮して制御を行うことが可能であ る。 As described above in detail, the power supply abnormality detection circuit of the present invention can accurately turn on / off the transistor because the transistor that warns of a failure is always driven by only one power supply. Therefore, even if the number of power sources is arbitrarily increased, the power source failure can be accurately managed. Therefore, the control can be performed in consideration of the variation in the base-emitter voltage of the transistor and the temperature characteristic.

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

【図1】本考案の電源異常検出回路の一実施例を示す回
路図である。
FIG. 1 is a circuit diagram showing an embodiment of a power supply abnormality detection circuit of the present invention.

【図2】本考案の電源異常検出回路の他の実施例を示し
た回路図である。
FIG. 2 is a circuit diagram showing another embodiment of the power supply abnormality detection circuit of the present invention.

【図3】従来の電源異常検出回路の回路図である。FIG. 3 is a circuit diagram of a conventional power supply abnormality detection circuit.

【符号の説明】[Explanation of symbols]

1、2 トランジスタ V1 〜V3 、−V1 〜−V3 電源 R1 〜R4 、R1- 〜R4- 抵抗 D1,2 、D1-,2- ダイオ−ド 1, 2 transistors V1 to V3, -V1 to -V3 power supplies R1 to R4, R1- to R4- resistors D1,2, D1-, 2-diode

Claims (1)

【実用新案登録請求の範囲】[Scope of utility model registration request] 【請求項1】 それぞれ異なった電圧(V1,V2,…Vn
)を出力するn個の電源の異常を検出する電源異常検
出回路であって、 前記電源中で最大の電圧V1 を出力する電源と共通電位
点との間に直列に設けられた(n+1)個の抵抗と、 i番目(i=1〜n)の抵抗と(i+1)番目の抵抗の
共通接続点と前記電圧(Vi )を出力する電源間に接続
したダイオ−ド(Di )と、 共通電位点に接続された(n+1)番目の抵抗とn番目
の抵抗との共通接続点にベ−スが接続され、エミッタが
共通電位点に接続されたトランジスタ(1)と、 を設け、いずれかの電源に故障が発生した時、前記トラ
ンジスタ(1)のコレクタ出力から前記電源の故障を検
出するようにしたことを特徴とした電源異常検出回路。
1. Different voltages (V1, V2, ... Vn)
) Output power source abnormality detection circuit for detecting abnormality of n power sources, wherein (n + 1) number of power source abnormality detection circuits are provided in series between the power source outputting the maximum voltage V1 in the power source and the common potential point. And a diode (Di) connected between a common connection point of the i-th (i = 1 to n) resistance and the (i + 1) -th resistance and a power source outputting the voltage (Vi), and a common potential. A transistor (1) having a base connected to the common connection point of the (n + 1) th resistance and the nth resistance connected to the point, and an emitter connected to the common potential point; A power supply abnormality detection circuit characterized in that, when a power supply failure occurs, the power supply failure is detected from the collector output of the transistor (1).
JP10705091U 1991-08-27 1991-12-25 Power failure detection circuit Expired - Lifetime JP2580932Y2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10705091U JP2580932Y2 (en) 1991-08-27 1991-12-25 Power failure detection circuit

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP6814091 1991-08-27
JP3-68140 1991-08-27
JP10705091U JP2580932Y2 (en) 1991-08-27 1991-12-25 Power failure detection circuit

Publications (2)

Publication Number Publication Date
JPH0534581U true JPH0534581U (en) 1993-05-07
JP2580932Y2 JP2580932Y2 (en) 1998-09-17

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
JP10705091U Expired - Lifetime JP2580932Y2 (en) 1991-08-27 1991-12-25 Power failure detection circuit

Country Status (1)

Country Link
JP (1) JP2580932Y2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001231158A (en) * 1999-12-30 2001-08-24 Deutsche Thomson Brandt Gmbh Power supply unit and protection circuit therefor

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001231158A (en) * 1999-12-30 2001-08-24 Deutsche Thomson Brandt Gmbh Power supply unit and protection circuit therefor
JP4507229B2 (en) * 1999-12-30 2010-07-21 ドイチエ トムソン−ブラント ゲゼルシヤフト ミツト ベシユレンクテル ハフツング Switching power supply unit with protection circuit

Also Published As

Publication number Publication date
JP2580932Y2 (en) 1998-09-17

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