JP2005253171A - Constant current source circuit and its control method - Google Patents

Constant current source circuit and its control method Download PDF

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JP2005253171A
JP2005253171A JP2004058710A JP2004058710A JP2005253171A JP 2005253171 A JP2005253171 A JP 2005253171A JP 2004058710 A JP2004058710 A JP 2004058710A JP 2004058710 A JP2004058710 A JP 2004058710A JP 2005253171 A JP2005253171 A JP 2005253171A
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voltage
constant current
constant
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Isamu Sho
蒋偉
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Azbil Corp
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Azbil Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To constantly stabilize internal power consumption irrespective of the number of load apparatuses. <P>SOLUTION: This constant current source circuit comprises: a constant voltage source CVS; a constant current part 1 that is inserted between the constant voltage source CVS and the load apparatus DDC, and feeds a constant current I<SB>S</SB>to the load apparatus DDC; and a voltage adjustment part 2 that adjusts an output voltage V<SB>S</SB>so that both-end voltages V<SB>D</SB>of the constant current part 1 are constant values. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、例えばカレントループ通信に使用される定電流源回路とその制御方法に関するものである。   The present invention relates to a constant current source circuit used for, for example, current loop communication and a control method thereof.

カレントループ通信は、電流の変化によって信号を伝送する通信方式であり、ケーブル延伸時にケーブルの抵抗による影響を受けにくい特徴がある（例えば、非特許文献１参照）。このようなカレントループ通信用の電源としては、ドロッパ方式の定電流源回路が用いられている（例えば、非特許文献２参照）。   Current loop communication is a communication method for transmitting a signal by a change in current, and has a feature that it is not easily affected by the resistance of the cable when the cable is extended (for example, see Non-Patent Document 1). As such a power supply for current loop communication, a dropper type constant current source circuit is used (for example, see Non-Patent Document 2).

図４は従来の定電流源回路の構成を示すブロック図である。定電流源回路は、定電圧源ＣＶＳと、定電流部１１とを有する。ＮＰＮトランジスタＱ１１と抵抗Ｒ１１，Ｒ１２とツェナダイオードＤ１１とからなるドロッパ方式の定電流部１１は、カレント通信用の一定電流ＩS を生成する。図４の定電流源回路では、出力端子１２，１３間に直列に接続される負荷機器ＤＤＣの台数が想定し得る最大数のときの負荷電圧ＶO に合わせて定電圧源ＣＶＳの出力電圧ＶS が予め設定される。定電流部１１は、定電圧源ＣＶＳの出力電圧ＶS と負荷電圧ＶO との差の電圧（ドロップ電圧）ＶD により動作する。定電圧源ＣＶＳの出力電圧ＶS は一定なので、定電流部１１の両端電圧ＶD は負荷機器ＤＤＣの台数により変動する。 FIG. 4 is a block diagram showing a configuration of a conventional constant current source circuit. The constant current source circuit includes a constant voltage source CVS and a constant current unit 11. A dropper type constant current unit 11 including an NPN transistor Q11, resistors R11 and R12, and a Zener diode D11 generates a constant current I S for current communication. In the constant current source circuit of FIG. 4, the output voltage V O of the constant voltage source CVS is matched to the load voltage V O when the number of load devices DDC connected in series between the output terminals 12 and 13 is the maximum number that can be assumed. S is preset. The constant current unit 11 operates by a voltage (drop voltage) V D that is a difference between the output voltage V S of the constant voltage source CVS and the load voltage V O. Since the output voltage V S of the constant voltage source CVS is constant, the voltage V D across the constant current unit 11 varies depending on the number of load devices DDC.

なお、出願人は、本明細書に記載した先行技術文献情報で特定される先行技術文献以外には、本発明に関連する先行技術文献を出願時までに発見するには至らなかった。
“通信の基本用語−カレントループ−”，［online］，株式会社ラインアイ，［平成１６年１月２７日検索］，インターネット＜http://www.lineeye.co.jp/html/term＿current.html＞ “３端子レギュレータの基本動作と正しい使い方”，［online］，トランジスタ技術編集部，［平成１６年１月２７日検索］，インターネット＜http://www.cqpub.co.jp/hanbai/pdf/34391＿onboard/34391＿onboard.pdf ＞ The applicant has not yet found prior art documents related to the present invention by the time of filing other than the prior art documents specified by the prior art document information described in this specification.
“Basic Terms of Communication-Current Loop”, [online], Line Eye, Inc. [searched on January 27, 2004], Internet <http://www.lineeye.co.jp/html/term_current.html > “Basic operation and correct usage of three-terminal regulator”, [online], Transistor Technology Editorial Department, [Search January 27, 2004], Internet <http://www.cqpub.co.jp/hanbai/pdf/ 34391_onboard / 34391_onboard.pdf>

図４に示した定電流源回路では、定電流部１１の両端電圧ＶD は負荷機器ＤＤＣの台数により変動し、負荷機器ＤＤＣの台数が少ないほど両端電圧ＶD は大きくなる。定電流部１１の両端電圧ＶD が必要以上に大きくなると、定電流部１１で無駄な電力を消費してしまい、定電流部１１の発熱が大きくなるという問題点があった。図５は、図４の定電流源回路の問題点を説明するための図であり、横軸は負荷機器ＤＤＣの台数、縦軸は電力である。図４の定電流源回路の場合、定電圧源ＣＶＳから入力される電力ＰはＰ＝ＶS×ＩSで一定である。これに対して、負荷機器ＤＤＣに出力される電力は、負荷機器ＤＤＣが減少すると低下し、一方、負荷機器ＤＤＣの減少による電圧ＶD の上昇により定電流部１１で消費される内部消費電力は増大する。このような定電流部１１の無駄な発熱を解決するために、定格の大きい部品の使用やヒートシンクの追加などの対策を行う必要があり、その結果、定電流源回路のサイズが大きくなってしまい、電源の小型化の阻害要因となっていた。電気製品の省エネルギーと省スペース設計は世の中の潮流となっており、カレントループ通信用の定電流源回路においても省エネルギーと省スペースが重要な設計事項となっている。 In the constant current source circuit shown in FIG. 4, the voltage V D at both ends of the constant current unit 11 varies depending on the number of load devices DDC, and the voltage V D at both ends increases as the number of load devices DDC decreases. When the voltage V D at both ends of the constant current portion 11 becomes larger than necessary, useless power is consumed in the constant current portion 11 and heat generation of the constant current portion 11 increases. FIG. 5 is a diagram for explaining problems of the constant current source circuit of FIG. 4, where the horizontal axis represents the number of load devices DDC and the vertical axis represents power. In the case of the constant current source circuit of FIG. 4, the power P input from the constant voltage source CVS is constant at P = V S × I S. On the other hand, the power output to the load device DDC decreases when the load device DDC decreases. On the other hand, the internal power consumption consumed by the constant current unit 11 due to the increase in the voltage V D due to the decrease in the load device DDC is Increase. In order to solve such a wasteful heat generation of the constant current section 11, it is necessary to take measures such as using a component with a large rating or adding a heat sink, resulting in an increase in the size of the constant current source circuit. This was an impediment to downsizing the power supply. Energy saving and space saving design of electrical products are a trend in the world, and energy saving and space saving are important design items even in a constant current source circuit for current loop communication.

本発明は、上記課題を解決するためになされたもので、内部消費電力を負荷機器の台数によらずに常に一定にすることができる定電流源回路とその制御方法を提供することを目的とする。   The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a constant current source circuit capable of constantly keeping internal power consumption constant regardless of the number of load devices, and a control method thereof. To do.

本発明の定電流源回路は、定電圧源と負荷との間に直列に挿入され、前記定電圧源から出力される電圧を入力として一定電流を前記負荷に供給する定電流部と、前記定電圧源と前記定電流部との間に設けられ、前記定電流部の両端電圧が一定値となるように前記定電圧源から前記定電流部に出力される電圧を調整する電圧調整部とを有するものである。本発明では、定電流部の両端に必要以上の電圧を加えないために、定電圧源から定電流部に出力される電圧を負荷電圧に比例して調整するようにした。
また、本発明の定電流源回路の１構成例において、前記電圧調整部は、前記定電圧源から出力される電圧をスイッチングしてパルス電圧に変換するスイッチング素子と、前記パルス電圧を整流平滑して前記定電流部に供給する整流平滑回路と、前記定電流部の両端電圧が一定値となるように前記スイッチング素子のオン／オフする時間を制御する制御回路とを備えるものである。 The constant current source circuit of the present invention is inserted in series between a constant voltage source and a load, and receives a voltage output from the constant voltage source and supplies a constant current to the load. A voltage adjusting unit that is provided between the voltage source and the constant current unit and adjusts a voltage output from the constant voltage source to the constant current unit so that a voltage across the constant current unit becomes a constant value; It is what you have. In the present invention, the voltage output from the constant voltage source to the constant current portion is adjusted in proportion to the load voltage in order not to apply an unnecessary voltage across the constant current portion.
Further, in one configuration example of the constant current source circuit of the present invention, the voltage adjusting unit switches a voltage output from the constant voltage source to convert it into a pulse voltage, and rectifies and smoothes the pulse voltage. And a rectifying / smoothing circuit that supplies the constant current part, and a control circuit that controls the time for which the switching element is turned on / off so that the voltage across the constant current part becomes a constant value.

また、本発明の定電流源回路の制御方法は、定電圧源と負荷との間に直列に挿入され、前記定電圧源から出力される電圧を入力として一定電流を前記負荷に供給する定電流部に対して、前記定電流部の両端電圧が一定となるように前記定電圧源から前記定電流部に出力される電圧を調整するようにしたものである。
また、本発明の定電流源回路の制御方法の１構成例は、前記定電圧源から出力される電圧をスイッチング素子でスイッチングしてパルス電圧に変換し、このパルス電圧を整流平滑して得られる電圧を前記定電流部に供給し、前記定電流部の両端電圧が一定値となるように前記スイッチング素子のオン／オフする時間を制御するようにしたものである。 The constant current source circuit control method of the present invention is a constant current that is inserted in series between a constant voltage source and a load, and that supplies a constant current to the load with the voltage output from the constant voltage source as an input. The voltage output from the constant voltage source to the constant current unit is adjusted so that the voltage across the constant current unit is constant.
Also, one configuration example of the constant current source circuit control method of the present invention is obtained by switching the voltage output from the constant voltage source with a switching element to convert it to a pulse voltage, and rectifying and smoothing the pulse voltage. A voltage is supplied to the constant current portion, and the time for turning on / off the switching element is controlled so that the voltage across the constant current portion becomes a constant value.

本発明によれば、定電圧源から定電流部に出力される電圧を調整する電圧調整部を設けることにより、定電流部の両端電圧が常に一定値となるようにすることができ、定電流部の消費電力を負荷の台数によらずに常に一定にすることができる。その結果、定電流部の無駄な発熱を抑えることができるので、定格値の小さい部品の採用やヒートシンクの不採用などの製品の小型化対策を実現することができる。   According to the present invention, by providing the voltage adjusting unit that adjusts the voltage output from the constant voltage source to the constant current unit, the voltage across the constant current unit can be always a constant value. The power consumption of the unit can be kept constant regardless of the number of loads. As a result, it is possible to suppress unnecessary heat generation in the constant current portion, and thus it is possible to realize measures for downsizing the product, such as adoption of parts having a small rated value and non-use of a heat sink.

以下、本発明の実施の形態について図面を参照して詳細に説明する。図１は本発明の実施の形態となる定電流源回路の構成を示すブロック図である。
定電流源回路は、定電圧源ＣＶＳと、定電圧源ＣＶＳと負荷機器ＤＤＣとの間に直列に挿入され、定電圧源ＣＶＳから出力される電圧を入力として一定電流ＩS を負荷機器ＤＤＣに供給する定電流部１と、定電圧源ＣＶＳと定電流部１との間に設けられ、定電流部１の両端電圧ＶD に応じて出力電圧ＶS を調整する電圧調整部２とを有する。 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a constant current source circuit according to an embodiment of the present invention.
The constant current source circuit is inserted in series between the constant voltage source CVS and the constant voltage source CVS and the load device DDC, and receives a voltage output from the constant voltage source CVS as an input, and supplies a constant current I S to the load device DDC. A constant current unit 1 to be supplied, and a voltage adjusting unit 2 that is provided between the constant voltage source CVS and the constant current unit 1 and adjusts the output voltage V S according to the voltage V D across the constant current unit 1 are provided. .

定電流部１は、ＮＰＮトランジスタＱ１と、抵抗Ｒ１，Ｒ２と、ツェナダイオードＤ１とから構成される。
電圧調整部２は、チョッパ回路と制御回路２０とを有し、チョッパ回路は、スイッチング素子であるパワーＭＯＳトランジスタＱ２と、ダイオードＤ２と、チョークコイルＬ１と、コンデンサＣ１とから構成される。 The constant current unit 1 includes an NPN transistor Q1, resistors R1 and R2, and a Zener diode D1.
The voltage adjustment unit 2 includes a chopper circuit and a control circuit 20, and the chopper circuit includes a power MOS transistor Q2, which is a switching element, a diode D2, a choke coil L1, and a capacitor C1.

電圧調整部２のパワーＭＯＳトランジスタＱ２は、定電圧源ＣＶＳの出力電圧をスイッチングしてパルス電圧に変換する。制御回路２０は、パワーＭＯＳトランジスタＱ２のゲート端子に制御パルス電圧Ｖ１を出力することにより、パワーＭＯＳトランジスタＱ２のスイッチング動作を制御する。
ダイオードＤ２とチョークコイルＬ１とコンデンサＣ１とからなる整流平滑回路は、パワーＭＯＳトランジスタＱ２のスイッチングによって発生したパルス電圧を整流平滑して、直流出力電圧Ｖｓに変換する。 The power MOS transistor Q2 of the voltage adjusting unit 2 switches the output voltage of the constant voltage source CVS to convert it into a pulse voltage. The control circuit 20 controls the switching operation of the power MOS transistor Q2 by outputting the control pulse voltage V1 to the gate terminal of the power MOS transistor Q2.
The rectifying / smoothing circuit including the diode D2, the choke coil L1, and the capacitor C1 rectifies and smoothes the pulse voltage generated by the switching of the power MOS transistor Q2, and converts the pulse voltage into the DC output voltage Vs.

定電流部１は、電圧調整部２の出力端子３，４間に、負荷機器ＤＤＣと定電流部１とが直列に接続されるように配置され、電圧調整部２の出力電圧ＶS と負荷電圧ＶO との差の電圧ＶD により動作し、負荷機器ＤＤＣに対して一定電流ＩS を出力する。 The constant current unit 1 is arranged between the output terminals 3 and 4 of the voltage adjustment unit 2 so that the load device DDC and the constant current unit 1 are connected in series, and the output voltage V S of the voltage adjustment unit 2 and the load It operates with the voltage V D that is the difference from the voltage V O, and outputs a constant current I S to the load device DDC.

ここで、定電流源回路の出力端子５，６間の負荷電圧ＶO は、出力端子５，６間に直列に接続された負荷機器ＤＤＣの台数によって変化する。図２は負荷電圧ＶO が低下した場合の定電流源回路の動作を示す波形図である。例えば、負荷機器ＤＤＣの台数が減少した場合、負荷電圧ＶO は低下する。ＶS＝ＶO＋ＶD であり、負荷電圧ＶO が低下した瞬間は電圧調整部２による電圧ＶS の調整が追いつかず、電圧ＶS は一定のままなので、負荷電圧ＶO が図２（ａ）のように低下した瞬間に、定電流部１の両端電圧ＶD は図２（ｂ）のように負荷電圧ＶO の低下分だけ上昇する。 Here, the load voltage V O between the output terminals 5 and 6 of the constant current source circuit varies depending on the number of load devices DDC connected in series between the output terminals 5 and 6. FIG. 2 is a waveform diagram showing the operation of the constant current source circuit when the load voltage V O is lowered. For example, when the number of load devices DDC decreases, the load voltage V O decreases. V S = a V O + V D, the load at the moment when the voltage V O drops not follow the adjustment of the voltage V S by the voltage adjusting unit 2, since the voltage V S remains constant, the load voltage V O in FIG. 2 ( At the moment when the voltage decreases as shown in a), the both-ends voltage V D of the constant current section 1 increases by the decrease in the load voltage V O as shown in FIG.

この定電流部１の両端電圧ＶD は、電圧調整部２の制御回路２０にフィードバックされる。制御回路２０は、入力された電圧ＶD に基づいてＰＷＭ制御を行う。すなわち、制御回路２０は、一定周期Ｔ毎に出力する制御パルス電圧Ｖ１のパルス幅Ｔｗｉｄｔｈを変えてパワーＭＯＳトランジスタＱ２がオン／オフする時間を変えることにより、定電流部１の両端電圧ＶD が一定になるように制御する。 The voltage V D across the constant current unit 1 is fed back to the control circuit 20 of the voltage adjustment unit 2. The control circuit 20 performs PWM control based on the input voltage V D. In other words, the control circuit 20 changes the pulse width Twidth of the control pulse voltage V1 output every fixed period T to change the time during which the power MOS transistor Q2 is turned on / off, whereby the voltage V D across the constant current unit 1 is changed. Control to be constant.

制御回路２０は、定電流部１の両端電圧ＶD が上昇した場合、制御パルス電圧Ｖ１のパルス幅Ｔｗｉｄｔｈを図２（ｃ）のように狭くする。パワーＭＯＳトランジスタＱ２は制御パルス電圧Ｖ１がハイレベルのときオンし、ローレベルのときオフするので、制御パルス電圧Ｖ１のパルス幅Ｔｗｉｄｔｈが狭くなると、一定周期ＴにおいてパワーＭＯＳトランジスタＱ２がオンする期間とオフする期間との比率が変わり、オンする期間が短くなるので、電圧調整部２の出力電圧ＶS は図２（ｄ）のように低下する。 When the both-end voltage V D of the constant current unit 1 increases, the control circuit 20 narrows the pulse width Twidth of the control pulse voltage V1 as shown in FIG. Since the power MOS transistor Q2 is turned on when the control pulse voltage V1 is at a high level and turned off when the control pulse voltage V1 is at a low level, when the pulse width Twidth of the control pulse voltage V1 is narrowed, a period during which the power MOS transistor Q2 is turned on in a certain period T Since the ratio with the OFF period changes and the ON period becomes shorter, the output voltage V S of the voltage adjusting unit 2 decreases as shown in FIG.

前述のとおり、ＶS＝ＶO＋ＶD であり、負荷電圧ＶO は負荷機器ＤＤＣの減少により低下した後は一定値を維持している。したがって、定電流部１の両端電圧ＶD は、図２（ｂ）のように電圧ＶS の低下分だけ降下して、一定値に復帰する。 As described above, V S = V O + V D , and the load voltage V O maintains a constant value after being lowered due to a decrease in the load device DDC. Therefore, the both-ends voltage V D of the constant current unit 1 drops by the drop of the voltage V S as shown in FIG. 2B and returns to a constant value.

図２に示した例は、負荷電圧ＶO が低下した場合であるが、負荷機器ＤＤＣの台数が増えた場合には、負荷電圧ＶO は上昇する。負荷電圧ＶO が上昇した瞬間、定電流部１の両端電圧ＶD は負荷電圧ＶO の上昇分だけ低下する。制御回路２０は、定電流部１の両端電圧ＶD が低下した場合、制御パルス電圧Ｖ１のパルス幅Ｔｗｉｄｔｈを広くする。これにより、一定周期ＴにおいてパワーＭＯＳトランジスタＱ２がオンする期間が長くなるので、電圧調整部２の出力電圧ＶS は上昇する。定電流部１の両端電圧ＶD は、電圧ＶS の上昇分だけ上昇して、一定値に復帰する。 The example shown in FIG. 2 is a case where the load voltage V O decreases, but when the number of load devices DDC increases, the load voltage V O increases. At the instant when the load voltage V O increases, the voltage V D across the constant current section 1 decreases by the increase in the load voltage V O. The control circuit 20 widens the pulse width Twidth of the control pulse voltage V1 when the voltage V D across the constant current unit 1 decreases. As a result, the period during which the power MOS transistor Q2 is turned on in the fixed period T becomes longer, so that the output voltage V S of the voltage adjusting unit 2 rises. The voltage V D at both ends of the constant current unit 1 increases by the increase of the voltage V S and returns to a constant value.

以上、説明したように負荷電圧ＶO の増減に応じて電圧調整部２の出力電圧ＶS を自動的に調整することにより、定電流部１の両端電圧ＶD を常に一定値に維持することができる。図３は本実施の形態の効果を説明するための図であり、横軸は負荷機器ＤＤＣの台数、縦軸は電力である。本実施の形態の場合、電圧調整部２の出力電圧ＶS は負荷機器ＤＤＣの台数に応じて自動的に調整され、これにより、電圧調整部２から入力される電力Ｐ＝ＶS×ＩSは負荷機器ＤＤＣの台数に比例して増減することになる。したがって、負荷機器ＤＤＣの台数が減少して負荷電圧ＶO が低下したとしても、電圧調整部２から入力される電力Ｐが自動的に減少するため、定電流部１で消費される内部消費電力が増大することはない。 As described above, the output voltage V S of the voltage adjustment unit 2 is automatically adjusted according to the increase or decrease of the load voltage V O , so that the voltage V D across the constant current unit 1 is always maintained at a constant value. Can do. FIG. 3 is a diagram for explaining the effect of the present embodiment, in which the horizontal axis represents the number of load devices DDC and the vertical axis represents power. In the case of the present embodiment, the output voltage V S of the voltage adjusting unit 2 is automatically adjusted according to the number of load devices DDC, and thereby the power P = V S × I S input from the voltage adjusting unit 2. Increases or decreases in proportion to the number of load devices DDC. Therefore, even if the number of load devices DDC decreases and the load voltage V O decreases, the power P input from the voltage adjustment unit 2 automatically decreases, so the internal power consumption consumed by the constant current unit 1 Will not increase.

こうして、本実施の形態では、定電流部１の消費電力を負荷機器ＤＤＣの台数によらずに常に一定にすることができる。その結果、本実施の形態の定電流源回路では、定電流部１の無駄な発熱を抑えることができるので、定格値の小さい部品の採用やヒートシンクの不採用などの製品の小型化対策を実現することができる。   Thus, in the present embodiment, the power consumption of the constant current unit 1 can always be made constant regardless of the number of load devices DDC. As a result, in the constant current source circuit of the present embodiment, it is possible to suppress wasteful heat generation of the constant current section 1, thereby realizing measures for downsizing of products such as adoption of parts with a small rated value or non-use of a heat sink. can do.

本発明は、例えばカレントループ通信用の定電流源回路に適用することができる。   The present invention can be applied to, for example, a constant current source circuit for current loop communication.

本発明の実施の形態となる定電流源回路の構成を示すブロック図である。It is a block diagram which shows the structure of the constant current source circuit used as embodiment of this invention. 本発明の実施の形態において負荷電圧が低下した場合の定電流源回路の動作を示す波形図である。It is a wave form diagram which shows operation | movement of the constant current source circuit when load voltage falls in embodiment of this invention. 本発明の実施の形態の定電流源回路の効果を説明するための図である。It is a figure for demonstrating the effect of the constant current source circuit of embodiment of this invention. 従来の定電流源回路の構成を示すブロック図である。It is a block diagram which shows the structure of the conventional constant current source circuit. 従来の定電流源回路の問題点を説明するための図である。It is a figure for demonstrating the problem of the conventional constant current source circuit.

符号の説明Explanation of symbols

１…定電流部、２…電圧調整部、ＣＶＳ…定電圧源、ＶO …負荷電圧、ＶS …電圧調整部の出力電圧、ＶD …定電流部の両端電圧、ＩS …定電流部の出力電流。
1 ... constant current section, 2 ... voltage regulator, CVS ... constant voltage source, V O ... load voltage, V S ... output voltage of the voltage regulator, V D ... voltage across the constant current section, I S ... constant current portion Output current.

Claims (4)

定電圧源と負荷との間に直列に挿入され、前記定電圧源から出力される電圧を入力として一定電流を前記負荷に供給する定電流部と、
前記定電圧源と前記定電流部との間に設けられ、前記定電流部の両端電圧が一定値となるように前記定電圧源から前記定電流部に出力される電圧を調整する電圧調整部とを有することを特徴とする定電流源回路。 A constant current unit that is inserted in series between a constant voltage source and a load, and that supplies a constant current to the load with a voltage output from the constant voltage source as an input;
A voltage adjusting unit that is provided between the constant voltage source and the constant current unit, and adjusts a voltage output from the constant voltage source to the constant current unit so that a voltage across the constant current unit becomes a constant value. And a constant current source circuit. 請求項１記載の定電流源回路において、
前記電圧調整部は、前記定電圧源から出力される電圧をスイッチングしてパルス電圧に変換するスイッチング素子と、前記パルス電圧を整流平滑して前記定電流部に供給する整流平滑回路と、前記定電流部の両端電圧が一定値となるように前記スイッチング素子のオン／オフする時間を制御する制御回路とを備えることを特徴とする定電流源回路。 The constant current source circuit according to claim 1,
The voltage adjusting unit switches a voltage output from the constant voltage source to convert it into a pulse voltage, a rectifying / smoothing circuit that rectifies and smoothes the pulse voltage and supplies the pulsed voltage to the constant current unit, and the constant voltage circuit. A constant current source circuit, comprising: a control circuit that controls a time period during which the switching element is turned on / off so that a voltage across the current portion has a constant value. 定電圧源と負荷との間に直列に挿入され、前記定電圧源から出力される電圧を入力として一定電流を前記負荷に供給する定電流部に対して、前記定電流部の両端電圧が一定となるように前記定電圧源から前記定電流部に出力される電圧を調整することを特徴とする定電流源回路の制御方法。   The voltage across the constant current unit is constant with respect to the constant current unit that is inserted in series between the constant voltage source and the load and supplies a constant current to the load with the voltage output from the constant voltage source as an input. The voltage output from the constant voltage source to the constant current unit is adjusted so that 請求項３記載の定電流源回路の制御方法において、
前記定電圧源から出力される電圧をスイッチング素子でスイッチングしてパルス電圧に変換し、このパルス電圧を整流平滑して得られる電圧を前記定電流部に供給し、前記定電流部の両端電圧が一定値となるように前記スイッチング素子のオン／オフする時間を制御することを特徴とする定電流源回路の制御方法。
In the control method of the constant current source circuit according to claim 3,
The voltage output from the constant voltage source is switched by a switching element to be converted into a pulse voltage, and the voltage obtained by rectifying and smoothing the pulse voltage is supplied to the constant current unit, and the voltage across the constant current unit is A method for controlling a constant current source circuit, comprising: controlling a time during which the switching element is turned on / off so as to be a constant value.
JP2004058710A 2004-03-03 2004-03-03 Constant current source circuit and its control method Pending JP2005253171A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011166987A (en) * 2010-02-12 2011-08-25 Fuji Electric Co Ltd Power supply apparatus
WO2014007255A1 (en) * 2012-07-03 2014-01-09 Ｊｘ日鉱日石エネルギー株式会社 Current control apparatus for solar cell inspection
JP2014100063A (en) * 2014-03-03 2014-05-29 Fuji Electric Co Ltd Power supply device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011166987A (en) * 2010-02-12 2011-08-25 Fuji Electric Co Ltd Power supply apparatus
WO2014007255A1 (en) * 2012-07-03 2014-01-09 Ｊｘ日鉱日石エネルギー株式会社 Current control apparatus for solar cell inspection
JP2014011430A (en) * 2012-07-03 2014-01-20 Jx Nippon Oil & Energy Corp Current controller for solar cell inspection
JP2014100063A (en) * 2014-03-03 2014-05-29 Fuji Electric Co Ltd Power supply device

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