JP6971878B2 - Light emitting element lighting control circuit - Google Patents

Light emitting element lighting control circuit Download PDF

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JP6971878B2
JP6971878B2 JP2018028523A JP2018028523A JP6971878B2 JP 6971878 B2 JP6971878 B2 JP 6971878B2 JP 2018028523 A JP2018028523 A JP 2018028523A JP 2018028523 A JP2018028523 A JP 2018028523A JP 6971878 B2 JP6971878 B2 JP 6971878B2
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light emitting
emitting element
lighting control
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JP2019145339A (en
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茂 村田
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Stanley Electric Co Ltd
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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection

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Description

本発明は、ＬＥＤなどの発光素子の点灯状態を制御するための技術に関する。 The present invention relates to a technique for controlling a lighting state of a light emitting element such as an LED.

近年、車両用灯具など種々の照明装置においてＬＥＤなどの発光素子が広く用いられている。発光素子の点灯状態の制御には、例えばＤＣ−ＤＣコンバータを含んだ昇降圧回路が用いられる（例えば、特許文献１参照）。また、過電流からの保護のため、発光素子に対して並列に保護素子（例えばツェナーダイオード）が接続される場合もある。 In recent years, light emitting elements such as LEDs have been widely used in various lighting devices such as vehicle lighting devices. A buck-boost circuit including, for example, a DC-DC converter is used to control the lighting state of the light emitting element (see, for example, Patent Document 1). Further, in order to protect from overcurrent, a protection element (for example, a Zener diode) may be connected in parallel with the light emitting element.

ところで、昇降圧回路を用いて発光素子の点灯状態を制御する場合に、電源投入時に発光素子と並列接続された保護素子に対して過電流が流れ、保護素子を破損する場合がある。これは、電源投入時に昇降圧回路の出力側に接続されるコンデンサの電荷がチャージされていないため、電源から保護素子を伝ってコンデンサへ至る電流経路が形成され、突入電流が生じてしまうことに起因する。 By the way, when the lighting state of the light emitting element is controlled by using the buck-boost circuit, an overcurrent may flow to the protection element connected in parallel with the light emitting element when the power is turned on, and the protection element may be damaged. This is because the charge of the capacitor connected to the output side of the buck-boost circuit is not charged when the power is turned on, so a current path is formed from the power supply to the capacitor through the protection element, and an inrush current is generated. to cause.

特開２０１３−１０９９３９号公報Japanese Unexamined Patent Publication No. 2013-109939

本発明に係る具体的態様は、発光素子の点灯制御装置において、電源投入時における保護素子への突入電流が生じるのを抑制可能な技術を提供することを目的の１つとする。 One of the specific aspects of the present invention is to provide a technique capable of suppressing an inrush current to a protective element when a power is turned on in a lighting control device for a light emitting element.

［１］本発明に係る一態様の点灯制御装置は、（ａ）発光素子と当該発光素子に対して並列接続された保護素子とを含む光源の点灯制御を行うための装置であって、（ｂ）電源に繋がる電流経路に一端が接続された誘導性素子と、（ｃ）前記誘導性素子の他端と基準電位端の間に接続されたスイッチング素子と、（ｄ）前記誘導性素子の他端と前記基準電位端の間に接続された容量性素子と、（ｅ）一端が前記電源に繋がる電流経路及び前記発光素子のカソードに接続され、他端が前記容量性素子と前記発光素子のアノードに接続されたバイパス用ダイオードと、を含む、点灯制御装置である。
［２］本発明に係る一態様の照明装置は、上記の点灯制御装置と、当該点灯制御装置によって制御される光源とを含む、照明装置である。 [1] The lighting control device of one aspect according to the present invention is a device for (a) controlling lighting of a light source including a light emitting element and a protection element connected in parallel to the light emitting element (a). b) an inductive element whose one end is connected to the current path connected to the power supply, (c) a switching element connected between the other end of the inductive element and the reference potential end, and (d) the inductive element. A capacitive element connected between the other end and the reference potential end, and (e) one end is connected to the current path connected to the power supply and the cathode of the light emitting element, and the other end is the capacitive element and the light emitting element. A lighting control device, including a bypass diode connected to the anode of the.
[2] One aspect of the lighting device according to the present invention is a lighting device including the above-mentioned lighting control device and a light source controlled by the lighting control device.

なお、本明細書において「接続」とは、ある回路要素と別の回路要素とが直接的に接続されている場合のほか、他の要素を介在させて間接的に接続されている場合も含む概念である。 In addition, in this specification, "connection" includes not only the case where a certain circuit element and another circuit element are directly connected, but also the case where they are indirectly connected by interposing another element. It is a concept.

上記構成によれば、発光素子の点灯制御装置において、電源投入時における保護素子への突入電流が生じるのを抑制することができる。 According to the above configuration, in the lighting control device for the light emitting element, it is possible to suppress the inrush current to the protection element when the power is turned on.

図１は、一実施形態の車両用灯具の全体構成を示すブロック図である。FIG. 1 is a block diagram showing an overall configuration of a vehicle lamp according to an embodiment. 図２は、一実施形態の点灯制御回路の詳細構成を示す回路図である。FIG. 2 is a circuit diagram showing a detailed configuration of the lighting control circuit of one embodiment. 図２は、比較例の点灯制御回路の詳細構成を示す回路図である。FIG. 2 is a circuit diagram showing a detailed configuration of a lighting control circuit of a comparative example.

図１は、一実施形態の車両用灯具の全体構成を示すブロック図である。図示の車両用灯具は、バッテリ３から電力供給を受けて光照射を行うものであり、制御基板１と光源２を含んで構成されている。バッテリ３と制御基板１の間にはリレー４が接続されている。光源２は、１つ以上の発光素子（例えばＬＥＤ）を含んで構成されている。 FIG. 1 is a block diagram showing an overall configuration of a vehicle lamp according to an embodiment. The illustrated vehicle lamp is supplied with electric power from the battery 3 to irradiate light, and includes a control board 1 and a light source 2. A relay 4 is connected between the battery 3 and the control board 1. The light source 2 is configured to include one or more light emitting elements (for example, LEDs).

制御基板１は、入力コネクタ１１、逆接保護回路１２、入力フィルタ１３、点灯制御回路（点灯制御装置）１４および電流検出回路１５を含んで構成されている。入力コネクタ１１は、制御基板１１とバッテリ３を接続するためのコネクタである。逆接保護回路１２は、バッテリ３と点灯制御回路１４の間に接続されており、バッテリ３に対して点灯制御回路１４が逆接続された際に点灯制御回路１４を保護するために電圧を遮断するものである。入力フィルタ１３は、雑音成分等が点灯制御回路１４に入力されないようにするフィルタ回路である。 The control board 1 includes an input connector 11, a reverse connection protection circuit 12, an input filter 13, a lighting control circuit (lighting control device) 14, and a current detection circuit 15. The input connector 11 is a connector for connecting the control board 11 and the battery 3. The reverse connection protection circuit 12 is connected between the battery 3 and the lighting control circuit 14, and cuts off the voltage to protect the lighting control circuit 14 when the lighting control circuit 14 is reversely connected to the battery 3. It is a thing. The input filter 13 is a filter circuit that prevents noise components and the like from being input to the lighting control circuit 14.

点灯制御回路１４は、バッテリ３から電力供給を受けて光源２に含まれる発光素子の点灯状態を制御するためのものであり、ＤＣ−ＤＣコンバータ等を含んで構成されている。電流検出回路１５は、光源２の発光素子に流れる電流を検出する。点灯制御回路１４は、この電流検出回路１５により検出される電流の大きさが一定となるように点灯制御を行う。 The lighting control circuit 14 is for controlling the lighting state of the light emitting element included in the light source 2 by receiving electric power from the battery 3, and includes a DC-DC converter and the like. The current detection circuit 15 detects the current flowing through the light emitting element of the light source 2. The lighting control circuit 14 performs lighting control so that the magnitude of the current detected by the current detection circuit 15 is constant.

図２は、一実施形態の点灯制御回路の詳細構成を示す回路図である。なお、説明を簡素化するために電流検出部１５については図示を省略している。図示の点灯制御回路１４は、コイル（誘導性素子）２１、ダイオード２２、トランジスタ２３、コンデンサ（容量性素子）２４、バイパス用ダイオード２５を含んで構成されている。これらのうち、少なくともコイル２１、トランジスタ２３、コンデンサ２４を含んで昇圧回路（ＤＣ−ＤＣコンバータ）が構成されている。 FIG. 2 is a circuit diagram showing a detailed configuration of the lighting control circuit of one embodiment. The current detection unit 15 is not shown for the sake of simplicity. The illustrated lighting control circuit 14 includes a coil (inductive element) 21, a diode 22, a transistor 23, a capacitor (capacitive element) 24, and a bypass diode 25. Of these, a booster circuit (DC-DC converter) is configured including at least a coil 21, a transistor 23, and a capacitor 24.

コイル２１は、一端側がバッテリ３に繋がる電流経路に接続され、他端側がダイオード２２のアノードおよびトランジスタ２３のドレインと接続されている。ダイオード２２は、アノード側がコイル２１の他端およびトランジスタ２３のドレインと接続され、カソード側がコンデンサ２４の一端側および光源２の発光素子３１のアノード側と接続されている。 One end of the coil 21 is connected to a current path connected to the battery 3, and the other end is connected to the anode of the diode 22 and the drain of the transistor 23. The anode side of the diode 22 is connected to the other end of the coil 21 and the drain of the transistor 23, and the cathode side is connected to one end side of the capacitor 24 and the anode side of the light emitting element 31 of the light source 2.

トランジスタ２３は、ゲートが図示しない制御部と接続され、ドレインがコイル２１とダイオード２２の中間接続点と接続されており、ソースが基準電位端（接地端）と接続されている。ゲートには制御部から制御信号が与えられる。なお、ここではスイッチング素子の一例として電界効果型トランジスタを用いているが、バイポーラトランジスタを用いてもよい。 In the transistor 23, the gate is connected to a control unit (not shown), the drain is connected to the intermediate connection point between the coil 21 and the diode 22, and the source is connected to the reference potential end (grounded end). A control signal is given to the gate from the control unit. Although a field effect transistor is used here as an example of the switching element, a bipolar transistor may be used.

コンデンサ２４は、一端側がダイオード２２と光源２の発光素子３１の中間接続点と接続され、他端側が基準電位端と接続されている。バイパス用ダイオード２５は、一端側がバッテリ３に繋がる電流経路に接続され、他端側がダイオード２２の他端側およびコンデンサ２４の一端側と接続されている。 One end of the capacitor 24 is connected to an intermediate connection point between the diode 22 and the light emitting element 31 of the light source 2, and the other end is connected to the reference potential end. One end of the bypass diode 25 is connected to the current path connected to the battery 3, and the other end is connected to the other end of the diode 22 and one end of the capacitor 24.

光源２は、発光素子３１と、この発光素子３１に対して並列接続されたツェナーダイオード（保護素子）３２を含んで構成されている。発光素子３１は、アノード側が点灯制御回路１４と接続され、カソード側がバッテリ３に繋がる電流経路に接続されている。 The light source 2 includes a light emitting element 31 and a Zener diode (protection element) 32 connected in parallel to the light emitting element 31. The light emitting element 31 is connected to the lighting control circuit 14 on the anode side and connected to the current path connected to the battery 3 on the cathode side.

ツェナーダイオード３２は、アノード側が発光素子３１のカソード側と接続され、カソード側が発光素子３１のアノード側と接続されている。別言すると、ツェナーダイオード３２は、アノード側がバッテリ３に繋がる電流経路に接続され、カソード側が点灯制御回路１４と接続されている。 The anode side of the Zener diode 32 is connected to the cathode side of the light emitting element 31, and the cathode side is connected to the anode side of the light emitting element 31. In other words, the Zener diode 32 has an anode side connected to a current path connected to the battery 3 and a cathode side connected to a lighting control circuit 14.

このような点灯制御回路１４の電源投入時における電流の流れは図中に太い点線で示したような流れとなる。具体的には、バッテリ３に繋がる電流経路から流れる電流は、バイパス用ダイオード２５を通ってコンデンサ２４に至り、コンデンサ２４に電荷をチャージする。コンデンサ２４に電荷がチャージされることで、光源２のツェナーダイオード３２の両端の電位差がなくなるので、ツェナーダイオード３２に過電流が流れるのを防止することができる。 The current flow when the power of the lighting control circuit 14 is turned on is as shown by the thick dotted line in the figure. Specifically, the current flowing from the current path connected to the battery 3 reaches the capacitor 24 through the bypass diode 25, and charges the capacitor 24. By charging the capacitor 24 with an electric charge, the potential difference between both ends of the Zener diode 32 of the light source 2 disappears, so that it is possible to prevent an overcurrent from flowing through the Zener diode 32.

図３は、比較例の点灯制御回路の詳細構成を示す回路図である。上記の実施形態の点灯制御回路との違いはバイパス用ダイオード２５が含まれていないことである。このような比較例の点灯制御回路１４ａの電源投入時における電流の流れは図中に太い点線で示したような流れとなる。具体的には、バッテリ３に繋がる電流経路から流れる電流は、光源２のツェナーダイオード３２を通ってコンデンサ２４に至り、コンデンサ２４に電荷をチャージする。コンデンサ２４に電荷がチャージされるまでの間、ツェナーダイオード３２には瞬間的に過電流が流れることになり、破損等の可能性が高まる。 FIG. 3 is a circuit diagram showing a detailed configuration of a lighting control circuit of a comparative example. The difference from the lighting control circuit of the above embodiment is that the bypass diode 25 is not included. The current flow when the power of the lighting control circuit 14a of the comparative example is turned on is as shown by a thick dotted line in the figure. Specifically, the current flowing from the current path connected to the battery 3 reaches the capacitor 24 through the Zener diode 32 of the light source 2 and charges the capacitor 24. Until the capacitor 24 is charged, an overcurrent momentarily flows through the Zener diode 32, increasing the possibility of damage or the like.

以上のような実施形態によれば、発光素子の点灯制御装置において、電源投入時における保護素子（ツェナーダイオード）への突入電流が生じるのを抑制することができる。 According to the above embodiment, in the lighting control device of the light emitting element, it is possible to suppress the inrush current to the protection element (Zener diode) at the time of turning on the power.

なお、本発明は上記した実施形態の内容に限定されるものではなく、本発明の要旨の範囲内において種々に変形して実施をすることが可能である。例えば、上記した実施形態で示した点灯制御回路における昇圧回路の構成は一例であり、これに限定されない。また、光源に含まれる発光素子は複数であってもよい。また、照明装置の一例として車両用灯具を示していたが照明装置の用途はこれに限定されない。 The present invention is not limited to the contents of the above-described embodiment, and can be variously modified and carried out within the scope of the gist of the present invention. For example, the configuration of the booster circuit in the lighting control circuit shown in the above embodiment is an example, and the present invention is not limited thereto. Further, the light source may include a plurality of light emitting elements. Further, although a vehicle lighting device has been shown as an example of a lighting device, the application of the lighting device is not limited to this.

１：制御基板
２：光源
３：バッテリ
１４：点灯制御回路
２１：コイル
２２：ダイオード
２３：トランジスタ
２４：コンデンサ
２５：バイパス用ダイオード
３１：発光素子
３２：ツェナーダイオード 1: Control board 2: Light source 3: Battery 14: Lighting control circuit 21: Coil 22: Diode 23: Transistor 24: Capacitor 25: Bypass diode 31: Light emitting element 32: Zener diode

Claims (3)

発光素子と当該発光素子に対して並列接続された保護素子とを含む光源の点灯制御を行うための装置であって、
電源に繋がる電流経路に一端が接続された誘導性素子と、
前記誘導性素子の他端と基準電位端の間に接続されたスイッチング素子と、
前記誘導性素子の他端と前記基準電位端の間に接続された容量性素子と、
一端が前記電源に繋がる電流経路及び前記発光素子のカソードに接続され、他端が前記容量性素子と前記発光素子のアノードに接続されたバイパス用ダイオードと、
を含む、点灯制御装置。 A device for controlling the lighting of a light source including a light emitting element and a protection element connected in parallel to the light emitting element.
An inductive element with one end connected to the current path connected to the power supply,
A switching element connected between the other end of the inductive element and the reference potential end,
Capacitive elements connected between the other end of the inductive element and the reference potential end,
A bypass diode having one end connected to the current path connected to the power source and the cathode of the light emitting element and the other end connected to the capacitive element and the anode of the light emitting element.
Lighting control device, including. 前記保護素子は、ツェナーダイオードであり、当該ツェナーダイオードは、アノードが前記発光素子のカソードと接続し、カソードが前記発光素子のアノードと接続するように並列接続される、
請求項１に記載の点灯制御装置。 The protection element is a Zener diode, and the Zener diode is connected in parallel so that the anode is connected to the cathode of the light emitting element and the cathode is connected to the anode of the light emitting element.
The lighting control device according to claim 1. 請求項１又は２に記載の点灯制御装置と、当該点灯制御装置によって制御される光源とを含む、照明装置。 A lighting device including the lighting control device according to claim 1 or 2 and a light source controlled by the lighting control device.
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JP2019145339A (en) 2019-08-29
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