JP2010231509A - Overvoltage detection circuit and overvoltage protection circuit - Google Patents

Overvoltage detection circuit and overvoltage protection circuit Download PDF

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Publication number
JP2010231509A
JP2010231509A JP2009078395A JP2009078395A JP2010231509A JP 2010231509 A JP2010231509 A JP 2010231509A JP 2009078395 A JP2009078395 A JP 2009078395A JP 2009078395 A JP2009078395 A JP 2009078395A JP 2010231509 A JP2010231509 A JP 2010231509A
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circuit
output
constant voltage
voltage
resistor
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Japanese (ja)
Inventor
Kiyoshi Morishima
潔 森島
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Seiko Epson Corp
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Seiko Epson Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology for detecting an overvoltage in a simple configuration and an overvoltage protecting method using the same. <P>SOLUTION: One end of a resistor R1 is connected to an output A of the constant voltage circuit 1, one end of a resistor R2 is connected to the output B of a constant voltage circuit 2, and a point C connecting the other end of the resistor R1 with the other end of the resistor R2, wherein the resistor R1 and the resistor R2 are serially connected, is connected to the input of a comparator 1. The resistance values of the resistor R1 and the resistor R2 are set to a large constant resistance value so that they may not overload the outputs of the constant voltage circuit 1, 2. The setting voltage V1 of the comparator 1 is set to a lower voltage than a voltage by which a circuit connected to the output A of the constant voltage circuit 1 and a circuit connected to the output B of the constant voltage circuit 2 are destroyed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は、定電圧回路から出力される異常電圧を検出する過電圧検出回路、その過電圧
検出回路を用いた過電圧保護回路に関する。 The present invention relates to an overvoltage detection circuit for detecting an abnormal voltage output from a constant voltage circuit, and an overvoltage protection circuit using the overvoltage detection circuit.

従来、一つの定電圧回路に対して、出力される異常電圧を検出するためには一つの過電
圧検出回路が必要で有った。そして、過電圧検出回路としては、ツェナーダイオード、ト
ランジスター等の幾つかの部品を組み合わせて回路を構成するか（例えば、特許文献１）
、集積回路（ＩＣ）を利用して回路を構成していた。 Conventionally, one overvoltage detection circuit has been required to detect an abnormal voltage output for one constant voltage circuit. As the overvoltage detection circuit, is a circuit configured by combining several components such as a Zener diode and a transistor (for example, Patent Document 1)?
The circuit is configured using an integrated circuit (IC).

特開平６−１３３５３８号公報JP-A-6-133538

しかしながら、一つの定電圧回路に対して、一つの過電圧検出回路が必要なうえ、ツェ
ナーダイオード、トランジスター等の幾つかの部品を組み合わせて回路を構成していたの
で、基板において過電圧検出回路が占める面積が大きくなるという問題が有った。また、
基板を製作する価格が高くなるという問題も有していた。
本発明は、上記した課題を踏まえ、簡単な構成により過電圧検出をできる技術を提供す
ること、その過電圧検出技術を用いた過電圧保護技術を提供することを目的とする。 However, since one overvoltage detection circuit is required for one constant voltage circuit and the circuit is configured by combining several components such as a Zener diode and a transistor, the area occupied by the overvoltage detection circuit on the substrate There was a problem that became larger. Also,
There was also a problem that the price for manufacturing the substrate was high.
In view of the above problems, an object of the present invention is to provide a technique capable of detecting an overvoltage with a simple configuration and to provide an overvoltage protection technique using the overvoltage detection technique.

本発明は、上述の課題の少なくとも一部を解決するためになされたものであり、以下の
形態または適用例として実現することが可能である。 SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[適用例１]適用例１の過電圧検出回路は、第１の定電圧回路の出力に接続された第１の
抵抗素子と、第２の定電圧回路の出力に接続された第２の抵抗素子と、が直列に接続され
、前記第１の抵抗素子と前記第２の抵抗素子との接続点の電圧を比較器の入力端子に入力
することを特徴とする。適用例１の過電圧検出回路よれば、定電圧回路から出力される電
圧の異常を検出することが可能となる。また、定電圧回路の数よりも少ない数の過電圧検
出回路によって、異常電圧の検出が可能となる。さらに、簡素な構成の過電圧検出回路が
可能となる。 Application Example 1 An overvoltage detection circuit according to Application Example 1 includes a first resistance element connected to the output of the first constant voltage circuit and a second resistance element connected to the output of the second constant voltage circuit. Are connected in series, and a voltage at a connection point between the first resistance element and the second resistance element is input to an input terminal of a comparator. According to the overvoltage detection circuit of Application Example 1, it is possible to detect an abnormality in the voltage output from the constant voltage circuit. Further, an abnormal voltage can be detected by the number of overvoltage detection circuits smaller than the number of constant voltage circuits. Furthermore, an overvoltage detection circuit with a simple configuration is possible.

[適用例２]適用例１の過電圧検出回路と、前記比較器の出力に基づいて、前記第１の定
電圧回路および前記第２の定電圧回路への電源供給を遮断する手段とを備えて、過電圧保
護回路としても良い。適用例２の過電圧保護回路によれば、簡素な構成の回路が可能とな
る。 Application Example 2 An overvoltage detection circuit according to Application Example 1 and means for cutting off power supply to the first constant voltage circuit and the second constant voltage circuit based on the output of the comparator. An overvoltage protection circuit may be used. According to the overvoltage protection circuit of Application Example 2, a circuit having a simple configuration is possible.

過電圧検出回路、その回路を用いた過電圧保護回路を示す回路図である。It is a circuit diagram which shows an overvoltage detection circuit and an overvoltage protection circuit using the circuit. 他の過電圧検出回路、その回路を用いた過電圧保護回路を示す回路図である。It is a circuit diagram which shows another overvoltage detection circuit and an overvoltage protection circuit using the circuit.

以上説明した本発明の構成および作用を一層明らかにするために、以下本発明を適用し
た過電圧検出回路、その回路を用いた過電圧保護回路について説明する。 In order to further clarify the configuration and operation of the present invention described above, an overvoltage detection circuit to which the present invention is applied and an overvoltage protection circuit using the circuit will be described below.

Ａ．実施例
図１は、過電圧検出回路、その回路を用いた過電圧保護回路を示す回路図である。定電
圧回路１の出力Ａに抵抗Ｒ１の一端を接続し、定電圧回路２の出力Ｂに抵抗Ｒ２の一端を
接続し、直列に接続された抵抗Ｒ１の他端と抵抗Ｒ２の他端との接続点Ｃを比較機１の入
力に接続する。抵抗Ｒ１と抵抗Ｒ２は、定電圧回路１の出力、定電圧回路２の出力に対し
て過負荷にならないように大きな定数の抵抗値に設定する。比較機１の設定電圧Ｖ１は、
定電圧回路１の出力Ａに接続される回路、および定電圧回路２の出力Ｂに接続される回路
が破壊に至る電圧よりも低い電圧に設定する。
例えば、定電圧回路１の出力電圧を５Ｖ、定電圧回路２の出力電圧を３Ｖ、抵抗Ｒ１と
抵抗Ｒ２の抵抗値をそれぞれ１００キロオームとする。ここで、定電圧回路１の出力Ａに
接続されている回路が動作不能に至る電圧が１０Ｖ以上とすると、Ａ点の電圧が１０Ｖに
なった時には、電圧異常として検出する必要がある。Ａ点の電圧を１０Ｖとし、Ｂ点の電
圧を３Ｖとすると、Ｃ点の電圧は６．５Ｖとなる。比較機１（ＩＣ１）のリファレンス電
圧Ｖ１を例えば６Ｖに設定しておくと、定電圧回路１の出力Ａに接続されている回路が破
壊される前に異常が検出され、回路の保護が可能となる。 A. FIG. 1 is a circuit diagram showing an overvoltage detection circuit and an overvoltage protection circuit using the circuit. One end of the resistor R1 is connected to the output A of the constant voltage circuit 1, and one end of the resistor R2 is connected to the output B of the constant voltage circuit 2, and the other end of the resistor R1 and the other end of the resistor R2 connected in series are connected. Connect the connection point C to the input of the comparator 1. The resistors R1 and R2 are set to large constant resistance values so as not to overload the output of the constant voltage circuit 1 and the output of the constant voltage circuit 2. The set voltage V1 of the comparator 1 is
The voltage connected to the output A of the constant voltage circuit 1 and the circuit connected to the output B of the constant voltage circuit 2 are set to a voltage lower than the voltage that causes destruction.
For example, the output voltage of the constant voltage circuit 1 is 5V, the output voltage of the constant voltage circuit 2 is 3V, and the resistance values of the resistors R1 and R2 are 100 kilohms, respectively. Here, if the voltage at which the circuit connected to the output A of the constant voltage circuit 1 becomes inoperable is 10 V or more, it is necessary to detect a voltage abnormality when the voltage at the point A becomes 10 V. If the voltage at point A is 10V and the voltage at point B is 3V, the voltage at point C is 6.5V. If the reference voltage V1 of the comparator 1 (IC1) is set to 6 V, for example, an abnormality is detected before the circuit connected to the output A of the constant voltage circuit 1 is destroyed, and the circuit can be protected. Become.

比較機１の出力をトランジスターＱ１のベースに接続する。トランジスターＱ１のエミ
ッターをＧＮＤに接続し、コレクターとＶｃｃ間に抵抗Ｒ３を接続する。Ｃ点の電圧が６
．５Ｖの時には、トランジスターＱ１が導通状態となり、コレクターの出力Ｄがロー（Ｌ
ｏｗ）となる。このとき、トランジスターＱ１はスイッチング素子として機能している。
トランジスターＱ１のコレクターは制御ＩＣ１０に接続されており、コレクター出力Ｄが
ローの場合は、制御ＩＣ１０によってスイッチＳＷ１が開放され、電源Ｖから定電圧回路
１および定電圧回路２への電圧供給が遮断される。従って、定電圧回路１からの異常電圧
の供給が停止されるので、定電圧回路１の出力Ａに接続されている回路が保護される。 The output of the comparator 1 is connected to the base of the transistor Q1. The emitter of the transistor Q1 is connected to GND, and a resistor R3 is connected between the collector and Vcc. The voltage at point C is 6
. At 5V, the transistor Q1 becomes conductive and the collector output D is low (L
ow). At this time, the transistor Q1 functions as a switching element.
The collector of the transistor Q1 is connected to the control IC 10, and when the collector output D is low, the switch SW1 is opened by the control IC 10 and the voltage supply from the power source V to the constant voltage circuit 1 and the constant voltage circuit 2 is cut off. The Accordingly, the supply of the abnormal voltage from the constant voltage circuit 1 is stopped, so that the circuit connected to the output A of the constant voltage circuit 1 is protected.

Ｂ．その他の実施例
図２は、その他の過電圧検出回路、その回路を用いた過電圧保護回路を示す回路図であ
る。定電圧回路１の出力Ａに抵抗Ｒ１の一端を接続し、定電圧回路２の出力Ｂに抵抗Ｒ２
の一端を接続し、抵抗Ｒ１の他端と抵抗Ｒ２の他端との接続点Ｃを比較機１と比較機２の
入力に接続する。抵抗Ｒ１と抵抗Ｒ２は、定電圧回路１の出力、定電圧回路２の出力に対
して過負荷にならないように大きな定数の抵抗値に設定する。比較機１の設定電圧Ｖ１は
、定電圧回路１の出力Ａに接続される回路、および定電圧回路２の出力Ｂに接続される回
路が破壊に至る電圧よりも低い電圧に設定する。また、比較機２の設定電圧Ｖ２は、定電
圧回路１の出力Ａに接続されている回路、および定電圧回路２の出力Ｂに接続されている
回路が動作不能に至る電圧よりも高い電圧に設定する。
例えば、定電圧回路１の出力電圧を５Ｖ、定電圧出力２の出力電圧を３Ｖ、抵抗Ｒ１と
抵抗Ｒ２の抵抗値を１００キロオームとする。ここで、定電圧回路１の出力Ａに接続され
ている回路が動作不能に至る電圧が１０Ｖ以上とすると、Ａ点の電圧が１０Ｖになった時
には、電圧異常として検出する必要がある。Ａ点の電圧を１０Ｖとし、Ｂ点の電圧を３Ｖ
とすると、Ｃ点の電圧は６．５Ｖとなる。比較機１（ＩＣ１）のリファレンス電圧Ｖ１を
例えば６Ｖに設定しておくと、定電圧回路１の出力Ａに接続されている回路が破壊される
前に異常が検出され、回路の保護が可能となる。 B. Other Embodiments FIG. 2 is a circuit diagram showing another overvoltage detection circuit and an overvoltage protection circuit using the circuit. One end of the resistor R1 is connected to the output A of the constant voltage circuit 1, and the resistor R2 is connected to the output B of the constant voltage circuit 2
Are connected, and a connection point C between the other end of the resistor R1 and the other end of the resistor R2 is connected to the inputs of the comparator 1 and the comparator 2. The resistors R1 and R2 are set to large constant resistance values so as not to overload the output of the constant voltage circuit 1 and the output of the constant voltage circuit 2. The set voltage V1 of the comparator 1 is set to a voltage lower than the voltage at which the circuit connected to the output A of the constant voltage circuit 1 and the circuit connected to the output B of the constant voltage circuit 2 are destroyed. The set voltage V2 of the comparator 2 is higher than the voltage at which the circuit connected to the output A of the constant voltage circuit 1 and the circuit connected to the output B of the constant voltage circuit 2 become inoperable. Set.
For example, the output voltage of the constant voltage circuit 1 is 5V, the output voltage of the constant voltage output 2 is 3V, and the resistance values of the resistors R1 and R2 are 100 kilohms. Here, if the voltage at which the circuit connected to the output A of the constant voltage circuit 1 becomes inoperable is 10 V or more, it is necessary to detect a voltage abnormality when the voltage at the point A becomes 10 V. The voltage at point A is 10V and the voltage at point B is 3V.
Then, the voltage at the point C is 6.5V. If the reference voltage V1 of the comparator 1 (IC1) is set to 6 V, for example, an abnormality is detected before the circuit connected to the output A of the constant voltage circuit 1 is destroyed, and the circuit can be protected. Become.

また、定電圧回路２の出力Ｂに接続されている回路が動作不能に至る電圧が１Ｖ以下と
すると、Ｂ点の電圧が１Ｖになった時には、電圧異常として検出する必要がある。Ａ点の
電圧を５Ｖ、Ｂ点の電圧を１Ｖとすると、Ｃ点の電圧は３Ｖとなる。比較機２（ＩＣ２）
のリファレンス電圧Ｖ２を例えば４Ｖに設定しておくと、定電圧回路２の出力Ｂに接続さ
れている回路が動作不能に至る前に異常が検出され、回路動作の維持が可能となる。
比較機１の出力７をＡＮＤ回路５の入力３に接続し、比較機２の出力１をＡＮＤ回路５
の入力２に接続する。ＡＮＤ回路５の出力１は制御ＩＣ１０に接続されている。定電圧回
路１の出力または定電圧回路２の出力に異常があると、Ｃ点の電圧がそれぞれ比較器２の
入力２、比較器１の入力５に入力され、ＡＮＤ回路５の出力１にロー（Ｌｏｗ）が出力さ
れる（通常のＡＮＤ回路５の出力１はハイ（Ｈｉｇｈ）となる）。ＡＮＤ回路５の出力１
は制御ＩＣ１０に接続されているので、ＡＮＤ回路５の出力１がローの場合は、制御ＩＣ
１０によってスイッチＳＷ１が開放され、電源Ｖから定電圧回路１および定電圧回路２へ
の電圧供給が遮断される。従って、定電圧回路１からの異常電圧の供給が停止されるので
、定電圧回路１の出力Ａに接続されている回路が保護される。 If the voltage at which the circuit connected to the output B of the constant voltage circuit 2 becomes inoperable is 1 V or less, it is necessary to detect a voltage abnormality when the voltage at the point B becomes 1 V. If the voltage at point A is 5V and the voltage at point B is 1V, the voltage at point C is 3V. Comparison machine 2 (IC2)
If the reference voltage V2 is set to 4 V, for example, an abnormality is detected before the circuit connected to the output B of the constant voltage circuit 2 becomes inoperable, and the circuit operation can be maintained.
The output 7 of the comparator 1 is connected to the input 3 of the AND circuit 5, and the output 1 of the comparator 2 is connected to the AND circuit 5.
Connect to input 2 of. The output 1 of the AND circuit 5 is connected to the control IC 10. If the output of the constant voltage circuit 1 or the output of the constant voltage circuit 2 is abnormal, the voltage at the point C is input to the input 2 of the comparator 2 and the input 5 of the comparator 1, respectively, and the output 1 of the AND circuit 5 is low. (Low) is output (output 1 of the normal AND circuit 5 becomes High). Output 1 of AND circuit 5
Is connected to the control IC 10, so if the output 1 of the AND circuit 5 is low, the control IC
The switch SW1 is opened by 10 and the voltage supply from the power source V to the constant voltage circuit 1 and the constant voltage circuit 2 is cut off. Accordingly, the supply of the abnormal voltage from the constant voltage circuit 1 is stopped, so that the circuit connected to the output A of the constant voltage circuit 1 is protected.

Ｃ．その他の実施形態
以上、本発明の実施の形態について説明したが、本発明はこうした実施の形態に何ら限
定されるものではなく、本発明の趣旨を逸脱しない範囲内において様々な形態で実施し得
ることは勿論である。
例えば、定電圧回路の出力電圧の違いを問わず、また、定電圧回路の数が三つ以上であ
っても、本発明を実施し得る。 C. Other Embodiments Although the embodiment of the present invention has been described above, the present invention is not limited to such an embodiment, and can be implemented in various forms without departing from the spirit of the present invention. Of course.
For example, the present invention can be implemented regardless of the difference in output voltage of the constant voltage circuit, and even when the number of constant voltage circuits is three or more.

１…定電圧回路１、２…定電圧回路２、３…比較機１、４…比較機２、
５…ゲートＩＣ（ＩＣ３）、６…抵抗Ｒ１、７…抵抗Ｒ２、８…抵抗Ｒ３
９…トランジスターＱ１、１０…制御ＩＣ。 DESCRIPTION OF SYMBOLS 1 ... Constant voltage circuit 1, 2 ... Constant voltage circuit 2, 3 ... Comparator 1, 4 ... Comparator 2,
5 ... Gate IC (IC3), 6 ... Resistor R1, 7 ... Resistor R2, 8 ... Resistor R3
9 ... Transistors Q1, 10 ... Control IC.

Claims (2)

第１の定電圧回路の出力に接続された第１の抵抗素子と、
第２の定電圧回路の出力に接続された第２の抵抗素子と、が直列に接続され、
前記第１の抵抗素子と前記第２の抵抗素子との接続点の電圧を比較器の入力端子に入力
する過電圧検出回路。 A first resistance element connected to the output of the first constant voltage circuit;
A second resistance element connected to the output of the second constant voltage circuit, and connected in series;
An overvoltage detection circuit that inputs a voltage at a connection point between the first resistance element and the second resistance element to an input terminal of a comparator. 請求項１に記載の過電圧検出回路と、
前記比較器の出力に基づいて、前記第１の定電圧回路および前記第２の定電圧回路への
電源供給を遮断する手段と、を備える過電圧保護回路。 An overvoltage detection circuit according to claim 1;
An overvoltage protection circuit comprising: means for cutting off power supply to the first constant voltage circuit and the second constant voltage circuit based on an output of the comparator;
JP2009078395A 2009-03-27 2009-03-27 Overvoltage detection circuit and overvoltage protection circuit Withdrawn JP2010231509A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2009078395A JP2010231509A (en) 2009-03-27 2009-03-27 Overvoltage detection circuit and overvoltage protection circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2009078395A JP2010231509A (en) 2009-03-27 2009-03-27 Overvoltage detection circuit and overvoltage protection circuit

Publications (1)

Publication Number Publication Date
JP2010231509A true JP2010231509A (en) 2010-10-14

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ID=43047254

Family Applications (1)

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JP2009078395A Withdrawn JP2010231509A (en) 2009-03-27 2009-03-27 Overvoltage detection circuit and overvoltage protection circuit

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102110977A (en) * 2011-01-21 2011-06-29 南车株洲电力机车研究所有限公司 Over-voltage protection method for DC bus voltage of wind power current transformer and circuit adopting same
KR20160029644A (en) * 2013-10-29 2016-03-15 삼성전자주식회사 Inverter circuit, and air conditioner and refrigerator using the same
CN108459646A (en) * 2017-02-22 2018-08-28 苏州普源精电科技有限公司 Constant resistance control loop

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102110977A (en) * 2011-01-21 2011-06-29 南车株洲电力机车研究所有限公司 Over-voltage protection method for DC bus voltage of wind power current transformer and circuit adopting same
KR20160029644A (en) * 2013-10-29 2016-03-15 삼성전자주식회사 Inverter circuit, and air conditioner and refrigerator using the same
KR102374725B1 (en) * 2013-10-29 2022-03-16 삼성전자주식회사 Inverter circuit, and air conditioner and refrigerator using the same
CN108459646A (en) * 2017-02-22 2018-08-28 苏州普源精电科技有限公司 Constant resistance control loop
CN108459646B (en) * 2017-02-22 2021-06-04 普源精电科技股份有限公司 Constant resistance control loop

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A300 Withdrawal of application because of no request for examination

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Effective date: 20120605