JP2009283839A - Light emitting diode driving device and illuminator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To integrally constitute a switch part to turn on/off a power input and a driving circuit part to drive a light source, and reduce the cost of a whole device and improve the processability. <P>SOLUTION: A light emitting diode driving device is constituted of a DC/DC converter 3, a voltage detection circuit 4, a current detection circuit 5, a control circuit part 6, and a current control part 7. The driving circuit part containing the DC/DC converter 3 contains, in an input part, the switch part 2 having a relay switch SW to open/close a power input path to the driving circuit part; and the driving circuit part and the switch part are constituted as the same unit. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a light emitting diode driving device that drives a light emitting diode used as a light source, and a lighting device including the same.

  In the lighting of vehicles such as automobiles, light emitting diodes (LEDs) are used as light sources in addition to halogen lamps and discharge lamps, and interior lights (room lamps), headlamps (headlights), and taillights (rear combination lamps). It is also being used for daytime running lights (DRL: headlights for improving visibility from oncoming vehicles in the daytime), which are being adopted in Europe.

  In current lighting systems using light-emitting diodes, a relay switch that opens and closes the power input path is provided, and the power supply path from the power supply is opened and closed by the relay in response to a switch signal input from the driver. It has become. In this case, the relay for opening / closing the power input and the drive circuit portion of the light emitting diode are separated from each other.

For example, in the light emitting diode driving device and the lighting device disclosed in Patent Document 1, a driving circuit unit that drives a plurality of light emitting diodes connected in series, and a relay switch that opens and closes a power input of the driving circuit unit And are arranged separately.
Japanese Patent Laying-Open No. 2006-210835, FIG.

  As described above, in a lighting device using a light emitting diode as a light source, when a power input of an in-vehicle lighting system or the like is turned on / off by a relay, conventionally, a driving circuit including a switch unit including a relay, a DC-DC converter, and the like. The parts are separated from each other and have a separate structure. For this reason, the casing of the switch section and the casing of the drive circuit section are required, and the parts cost and the number of assembly steps are increased. Therefore, the cost cannot be reduced beyond a certain level, which is an obstacle to the cost reduction.

  The present invention has been made in view of the above circumstances, and it is possible to integrally form a switch part for turning on / off a power input and a drive circuit part for driving a light source, thereby reducing the cost of the entire apparatus and improving workability. An object of the present invention is to provide a light emitting diode driving device and a lighting device.

The present invention is a light emitting diode driving device that drives a light emitting diode used as a light source by receiving power supply from a DC power supply, and includes a DC / DC converter that boosts or steps down output power from the DC power supply to a required voltage. There is provided a light emitting diode drive device comprising: a drive power supply unit including: a switch unit that is configured by the same unit as the drive power supply unit and opens and closes a power input path from the DC power supply to the drive power supply unit.
With the above configuration, the switch unit for turning on / off the power input and the drive circuit unit for driving the light source can be integrally configured, thereby reducing the cost of the entire apparatus and improving the workability. At this time, the housing of the drive circuit section and the switch section can be shared, so that the component cost can be reduced and the assembly cost can be reduced, so that the cost of the entire lighting system can be reduced.

Further, the present invention is the light emitting diode drive device described above, further comprising an inrush current reducing element connected in series to an output path of the DC / DC converter, and the switch unit from the DC power supply to the drive power supply unit. Two-contact relay switch having a first switch for opening and closing the power input path, and a second switch that closes with a predetermined time delay after the first switch is closed and bypasses the inrush current reducing element Including those that are configured.
With the above configuration, an inrush current to the light emitting diode can be reduced with an inexpensive configuration, and a configuration that contributes to reducing the stress of the light emitting diode can be realized. In this case, the life of the light emitting diode can be extended, and the options for the light emitting diode that can be used as a system can be expanded.

  Further, the present invention is the light emitting diode drive device described above, wherein an input terminal for inputting a power supply voltage supplied from the DC power supply and a switch signal supplied to the switch unit, and an output from the DC / DC converter. An output terminal that outputs drive power to the light emitting diode, and the input terminal and the output terminal are externally provided in a separate or integral shape in a housing of the unit on which the drive power supply unit and the switch unit are mounted. And those that can be connected to external wiring.

  Further, the present invention includes the light emitting diode driving device described above, wherein a housing of a unit on which the driving power supply unit and the switch unit are mounted is configured by a resin case.

  According to another aspect of the present invention, there is provided a light emitting diode driving device according to any one of the above, a light emitting unit connected to the light emitting diode driving device, and configured by connecting a plurality of light emitting diodes, the light emitting diode driving device, and the light emitting device. An illumination device is provided that includes an instrument body that holds the unit.

  Further, the present invention is a light-emitting diode driving device according to any one of the above, and a light-emitting unit connected to the light-emitting diode driving device, configured by connecting a plurality of light-emitting diodes, and disposed in a vehicle interior of a vehicle, A vehicle interior lighting device is provided.

  Further, the present invention is a light-emitting diode driving device according to any one of the above, a light-emitting unit that is connected to the light-emitting diode driving device and is configured by connecting a plurality of light-emitting diodes, and irradiates light around the vehicle, A vehicle lighting device is provided.

  According to the present invention, a light emitting diode driving device and an illumination that can integrally form a switch unit that turns on and off a power input and a driving circuit unit that drives a light source, and that can reduce the cost of the entire device and improve workability. Equipment can be provided.

  In the following embodiments, as an example of a light-emitting diode driving device and a lighting device, a configuration example in the case of being used for a headlamp mounted on a vehicle is shown.

(Embodiment 1)
FIG. 1 is a diagram showing a circuit configuration of a light emitting diode driving apparatus according to Embodiment 1 of the present invention. The light emitting diode driving device of this embodiment includes a DC power source 1 such as an automobile battery, a DC / DC converter 3, a voltage detection circuit 4, a current detection circuit 5, a control circuit unit 6, a current control unit 7, and a light emitting unit 8. Configured. Here, the DC / DC converter 3, the voltage detection circuit 4, the current detection circuit 5, the control circuit unit 6, and the current control unit 7 constitute a drive circuit unit that drives the light emitting unit 8. The DC power source 1 and the light emitting unit 8 are usually provided and connected separately from the drive circuit unit.

  The DC-DC converter 3 functions as a DC-DC converting means for stepping up or down the DC power supply voltage supplied from the DC power supply 1 to a required voltage. The DC-DC converter 3 includes a switch unit 2 having a relay switch SW that opens and closes a power input path to the drive circuit unit at an input unit. The DC-DC converter 3, the switch unit 2, Are composed of the same unit.

  The output terminal in the drive circuit unit of the present embodiment has an output terminal AB where a light emitting diode having a high forward voltage Vf is connected in parallel, and an output terminal CD where a light emitting diode is connected in parallel. . A light emitting unit 8 composed of a plurality of light emitting diodes is connected to the output terminals AB and CD. The light emitting unit 8 is configured by light emitting diodes LED1 and LED2 being connected in series and parallel in two systems, corresponding to the output terminals AB and CD.

  The voltage detection circuit 4 detects the voltage applied to both ends of the series-parallel light emitting diode group of the light emitting unit 8. The current detection circuit 5 detects a current flowing through the light emitting diode group of the light emitting unit 8. The current control unit 7 includes a variable resistor VR that is connected in parallel with the output terminal A-B to which the light emitting diode having a high forward voltage Vf is connected and whose resistance value can be varied.

  The control circuit unit 6 includes a reference current setting unit 11, a comparator unit 12, a PWM control unit 13, and a driver unit 14. The reference current setting unit 11 sets a reference value for the drive current based on the detection voltage Vx output from the voltage detection circuit 4. The comparator unit 12 compares the reference value output from the reference current setting unit 11 with the detection voltage Vy indicating the current detection value output from the current detection circuit 5. The PWM control unit 13 outputs a PWM signal for adjusting the on-duty ratio of the switching element Q1 of the DC-DC converter 3 based on the comparison result in the comparator unit 12. The driver unit 14 turns the switching element Q1 on and off at an on-duty ratio corresponding to the PWM signal output from the PWM control unit 13.

  The relay switch SW of the switch unit 2 is composed of, for example, a semiconductor element, and is mounted on a circuit board of a light emitting diode driving circuit on which the DC / DC converter 3 is mounted. Thus, the configuration in which the switch unit 2 is integrally provided in the drive circuit unit and mounted on the circuit board of the drive circuit unit contributes to eliminating the loss between the switch unit and the drive circuit unit as compared with the conventional configuration. is doing.

  The DC-DC converter 3 is formed of a known flyback type, and includes a switching element Q1, a transformer T, a diode D1, and a smoothing capacitor C0 in addition to the relay switch SW of the switch unit 2. The switching element Q1 is composed of a power MOSFET or the like, and is turned on / off by the control circuit unit 6. One end of the primary winding of the transformer T is connected to the positive electrode of the DC power source 1 via the relay switch SW of the switch unit 2, and the other end is connected to the negative electrode of the DC power source 1 via the switching element Q1. The anode of the diode D1 is connected to one end of the secondary winding of the transformer T, and the smoothing capacitor C0 is connected between the cathode of the diode D1 and the other end of the secondary winding of the transformer T.

  In the DC-DC converter 3, when the switching element Q1 is turned on by the control circuit unit 6, current flows in the primary winding of the transformer T, energy is stored in the transformer T, and the switching element Q1 is turned off. In this case, the energy stored in the transformer T is supplied from the secondary winding to the smoothing capacitor C0 via the diode D1. Therefore, by performing PWM control of the switching element Q1 by the control circuit unit 6, a desired output voltage V2 can be obtained from a voltage higher than the power supply voltage of the DC power supply 1 to a lower voltage.

  Here, the basic operation of the light emitting diode driving device of the present embodiment will be described. When a lighting on instruction is given by a driver signal or the like from the driver, the relay switch SW of the switch unit 2 is closed and turned on, and the control circuit unit 6 operates the DC-DC converter 3 to output the DC voltage V2. Then, the DC voltage V2 is applied to the light emitting unit 8, and a DC current I0 flows. The control circuit unit 6 adjusts the output voltage V2 of the DC-DC converter 3 by PWM control of the switching element Q1 so that the detection value Vy of the current detection circuit 5 is constant.

  For example, in the case where the light emitting unit 8 is configured by connecting four series connection circuits of four light emitting diodes in parallel, assuming that the rated value of the forward voltage Vf of each light emitting diode is 3.5 V, in a steady state, The output voltage V2 of the DC-DC converter 3 is set to 3.5V × 4 = 14V. As a result, the rated forward DC current I 0 can flow through the light emitting unit 8. Further, since the DC-DC converter 3 of the present embodiment can perform either a step-up operation or a step-down operation by the control circuit unit 6, when a vehicle battery is used as the DC power source 1, the power supply voltage of the battery is 12V. In this case, the DC-DC converter 3 may be boosted, and if the power supply voltage is 24V or 48V, the DC-DC converter 3 may be stepped down. As a result, the light emitting unit 8 can be driven at a constant current regardless of the power supply voltage of the DC power supply 1.

  In the first embodiment, the switch unit 2 that opens and closes the power supply path from the DC power source 1 to the drive circuit unit in accordance with a switch signal from the driver is connected to the drive circuit unit together with the DC-DC converter 3 and the like. The same unit is configured as a single unit and is housed in the drive circuit unit. As a result, conventionally, a process for mounting the relay part and the drive circuit part separately was required as construction work, but with this integrated structure, the work process during assembly can be reduced and construction efficiency can be reduced. Can be improved. Further, the relay unit and the drive circuit unit can share the housing, and the cost of the entire apparatus can be reduced.

(Embodiment 2)
FIG. 2 is a diagram illustrating a circuit configuration of a light emitting diode driving apparatus according to Embodiment 2 of the present invention, and FIG. 3 is a diagram illustrating a circuit configuration of a switch unit according to Embodiment 2. The second embodiment is an example in which the configuration of the switch unit of the first embodiment is changed.

  The switch unit 2A according to the second embodiment has two switches SW1 and SW2 as shown in FIG. The switch SW1 as the first switch of the switch unit 2A is arranged on the power input path from the DC power source 1 to the DC / DC converter 3 as in the switch unit 2 of the first embodiment. Further, the switch SW2 as the second switch of the switch unit 2A is connected in parallel to the resistor 19 serving as an inrush current reducing element connected in series to the output path of the DC / DC converter 3 in the previous stage of the output terminal C. Thus, an inrush current reducing circuit 10 that reduces the inrush current to the light emitting unit 8 is configured.

  As shown in FIG. 3, the switch unit 2A is configured by a relay switch having a two-contact relay configuration having a switch SW1 and a switch SW2. In the switch unit 2A, the drive inputs of the switch SW1 and the switch SW2 are connected in parallel, and a delay circuit 18 is provided between the drive inputs of one switch SW2. The drive inputs of these switches SW1 and SW2 are connected to the DC power supply 17 for driving the relay and the switch SW0, and when the switch SW0 is turned on / off by a switch signal supplied according to the driver's operation or the like, The switch SW1 is turned on / off, and the switch SW2 is turned on / off with a slight delay. The delay time by the delay circuit 18 is, for example, about several milliseconds to several tens of milliseconds. Here, one switch SW1 constitutes a switch that opens and closes a power input path to the drive circuit unit, and the other switch SW2 constitutes a switch that inserts / passes the inrush current reduction circuit 10.

  Further, the current control unit 7A includes a transistor Tr that is variable in resistance and is connected in parallel with the output terminal A-B to which the light emitting diode having a high forward voltage Vf is connected. In addition to the configuration of the first embodiment shown in FIG. 1, the control circuit unit 6A includes a Vf detection unit 15 that detects the forward voltage Vf of the light emitting diode, and the transistor Tr of the current control unit 7A based on the forward voltage Vf. And a base current control unit 16 that controls the base current and varies the resistance value of the current control unit 7A.

  In the second embodiment, when a lighting ON instruction is given by a switch signal from the driver and the switch SW0 is turned on, the switch SW1 is first closed and turned on in the two-contact relay switch of the switch unit 2A, and then the switch SW1 is turned on. The switch SW2 is closed and turned on with a delay of about several milliseconds to several tens of milliseconds.

  In the light emitting diode driving circuit, since the discharge current from the capacitor at the output stage of the DC / DC converter instantaneously flows to the light emitting diode at the time of start-up, electrical stress may be generated on the light emitting diode. Therefore, in the present embodiment, the inrush current reduction circuit 10 is provided, and the inrush current reduction circuit 10 is switched on and off at the start-up by using a relay switch having a plurality of contacts, and the inrush current reduction circuit is applied only for a predetermined time immediately after the drive circuit unit is turned on. 10 is connected. As a result, the current flowing to the light emitting unit 8 at the time of startup is passed through the resistor 19 to be absorbed, and the inrush current at the time of starting the light emitting diode can be suppressed, so that the electrical stress of the light emitting diode can be reduced. At this time, after about several msec to several tens of msec after the switch SW1 is turned on, the switch SW2 is closed and the resistor 19 is bypassed. Therefore, in the subsequent operation, the power loss in the resistor 19 of the inrush current reducing circuit 10 is reduced. Does not occur.

  According to the second embodiment, in addition to the effect of the first embodiment, there is an effect that the inrush current to the light emitting diode can be reduced with an inexpensive configuration. As a result, the lifetime of the light-emitting diode can be extended, and the choices of light-emitting diodes that can be used as a system can be expanded.

  In the following embodiments, some configuration examples of the unit configuration of the light emitting diode driving device will be shown.

(Embodiment 3)
4 is a perspective view showing an external configuration of a drive circuit unit including a light emitting diode driving device according to Embodiment 3 of the present invention, and FIG. 5 is a diagram showing a schematic configuration of an illumination device including the light emitting diode driving device of Embodiment 3. is there.

  In the third embodiment, the circuit board on which the driving circuit unit of the light emitting diode driving device of the first embodiment shown in FIG. 1 or the second embodiment shown in FIG. It is a structural example. On the circuit board inside the drive circuit unit 21, circuits of a DC / DC converter 3, a voltage detection circuit 4, a current detection circuit 5, a control circuit unit 6, and a current control unit 7 that are integrated with a switch unit are mounted. .

  In the drive circuit unit 21, an input terminal 23 to which a power supply voltage supplied from a battery or the like and a switch signal supplied according to a driver's operation or the like is input is disposed on the side surface of the housing, and power is supplied to the light emitting unit 8. Is provided on the upper surface of the housing. In the third embodiment, the input terminal 23 and the output terminal 22 are separated from each other, and are arranged on surfaces that intersect with each other substantially perpendicularly.

  FIG. 5 shows a configuration in which the drive circuit unit 21 is attached to a headlamp 26 as a lighting device. The headlamp 26 is arranged such that a light emitting diode 24 as a light source irradiates forward, and a heat dissipating component 25 is arranged behind the light emitting diode 24. A drive circuit unit 21 is attached to the bottom surface of the headlamp 26. In this case, the input terminal 23 on the rear side surface of the drive circuit unit 21 is formed of a waterproof connector, and the input terminal 23 is connected to a connector for wiring to the vehicle body. The output terminal 22 on the upper surface of the drive circuit unit 21 is connected to a socket for wiring to the light emitting diode 24 side in the lamp. Then, a power supply voltage and a switch signal are input from the outside to the input terminal 23 of the drive circuit unit 21, and output drive power is supplied from the output terminal 22 to the light emitting diode 24.

  The third embodiment has a structure in which the input unit and the output unit of the drive circuit unit are separated from each other, and is useful when the directions of the input unit and the output unit are different. Further, it is useful in a configuration in which wiring from the vehicle body is connected to the drive circuit unit.

(Embodiment 4)
FIG. 6 is a perspective view showing an external configuration of a drive circuit unit including a light emitting diode driving device according to Embodiment 4 of the present invention, and FIG. 7 is a diagram showing a schematic configuration of an illumination device including the light emitting diode driving device of Embodiment 4. is there.

  The fourth embodiment is a modification of the third embodiment, and is a configuration example in which the input terminal and the output terminal are arranged on the same surface. In the drive circuit unit 21A of the fourth embodiment, an input / output terminal 27 composed of the same or a plurality of couplers is arranged on the upper surface of the casing. The input / output terminal 27 includes an input terminal to which a power supply voltage and a switch signal are input, and an output terminal from which driving power of the light emitting diode is output.

  FIG. 7 shows a configuration in which a drive circuit unit 21A is attached to a headlamp 26A as a lighting device. The headlamp 26A is a partial modification of the configuration shown in FIG. 5, and an external terminal 28 for connecting wiring from the vehicle main body is provided on the rear surface. The drive circuit unit 21A is attached to the socket at the bottom of the headlamp 26A. In this case, the input / output terminal 27 on the upper surface of the drive circuit unit 21A is connected to the wiring in the lamp, and the external terminal 28 of the headlamp lamp 26A is connected to the wiring to the vehicle body. Then, the power supply voltage and the switch signal are input from the outside to the input / output terminal 27 of the drive circuit unit 21A through the external terminal 28 of the headlamp 26A, and the output drive power is supplied from the input / output terminal 27 to the light emitting diode 24. Is done.

  The fourth embodiment is useful when the input unit and the output unit of the drive circuit unit are arranged in the same direction. Further, it is useful in a configuration in which wiring from the vehicle body is connected to the lamp and input / output wiring is connected to the drive circuit unit of the drive circuit unit in the lamp.

(Embodiment 5)
8A and 8B are diagrams showing an external configuration of a drive circuit unit including a light emitting diode drive device according to Embodiment 5 of the present invention, where FIG. 8A is a perspective view, FIG. 8B is a side view, and FIG. 8C is a bottom view. FIG. 9 is a diagram illustrating a schematic configuration of an illumination device including the light-emitting diode driving device according to the fifth embodiment.

  The fifth embodiment is another modification of the third embodiment, and is an example in which the input terminal and the output terminal are arranged on the same surface, and are configured in different shapes. In the drive circuit unit 21B according to the fifth embodiment, an input terminal 31 and an output terminal 32 configured by metal terminals are disposed on the bottom surface of the casing. The input terminal 31 is configured in a male shape (convex shape), and is connected to a female-shaped (concave shape) connector or socket so that a power supply voltage and a switch signal are input. The output terminal 32 is configured in a female shape (concave shape), and is connected to a male-shaped (convex shape) connector or socket for wiring to the light emitting unit so that driving power to the light emitting diode is output.

  FIG. 9 shows a configuration in which a drive circuit unit 21B is connected to a headlamp 26B as a lighting device. The headlamp 26 </ b> B is a partial modification of the configuration of FIG. 5, and wiring for supplying driving power extends from the rear surface and is connected to the relay box 33. The relay box 33 is connected to a wiring to the vehicle body to which a power supply voltage and a switch signal are input. For this reason, the drive output of light emitting diodes, such as a headlamp, can be controlled by incorporating the drive circuit unit 21B into the relay box 33. The drive circuit unit 21B is attached to the relay box 33, and the input terminal 31 and the output terminal 32 are connected thereto. In this case, the input terminal 31 of the drive circuit unit 21B is connected to the wiring to the vehicle body, and the power supply voltage and the switch signal are input from the outside. In addition, the output terminal 32 of the drive circuit unit 21B is connected to the wiring of the headlamp 26B, and output drive power is supplied to the light emitting diode 24.

  The in-vehicle relay box is usually in the engine room with the hood of the vehicle opened or in the vicinity of the driver's seat or passenger's seat in the vehicle, so if a drive circuit unit is provided in the relay box, it can be easily replaced. Workability is good. On the other hand, for example, in the case of a light-emitting diode drive circuit for a headlamp, in the configuration as in Embodiment 3 or 4 described above, the drive circuit unit is disposed on the lower surface of the headlamp, so that man-hours are required for replacement work. Cost. In some cases, it is necessary to remove the entire headlamp and attach the drive circuit unit after replacement. On the other hand, in the configuration of the fifth embodiment, inspection can be performed in the relay box, and a unit with extremely good maintainability can be configured. In addition, workability is expected to improve when assembling lamps or vehicles.

(Other embodiments)
As another embodiment, in the drive circuit unit in which the switch unit is integrated with the drive circuit unit as shown in FIGS. 4, 6, and 8, the housing is configured by a resin case. This embodiment is configured to contribute to weight reduction of the system, and since the drive circuit unit in which the drive circuit unit and the switch unit are integrated is housed in the resin case, it is easy to handle.

  As still another embodiment, a lighting fixture is provided that includes a drive circuit unit of the light-emitting diode driving device of each of the above embodiments, a light-emitting unit, and a fixture body that holds the drive circuit unit and the light-emitting unit. Or the light-emitting part is provided in vehicle interiors, such as a motor vehicle, and the drive circuit part comprises the illuminating device for vehicle interiors provided in the relay box etc. in the vehicle. Alternatively, a vehicle lighting device (headlight device) in which a light-emitting unit composed of a series-parallel circuit of high-intensity light-emitting diodes is used for a headlamp of a vehicle such as an automobile, and a drive circuit unit is provided in a lamp or the like. Configure. Even in such various lighting devices, by applying each of the above-described embodiments, when using a light emitting unit using a light emitting diode, the switch unit and the drive circuit unit can be configured integrally, thereby reducing the overall cost of the device. Workability can be improved.

  As described above, in this embodiment, construction efficiency is improved by integrating and storing the switch part by the relay switch that opens and closes the power input path from the DC power supply to the drive circuit part in the drive circuit unit. can do. In addition, since the casing of the switch unit and the drive circuit unit can be shared, the parts cost can be reduced and the assembly cost can be reduced, so that the cost of the entire lighting system can be reduced.

  Furthermore, by providing a relay switch having a plurality of contacts, an inrush current to the light emitting diode can be reduced with an inexpensive configuration, and a configuration that contributes to reducing the stress of the light emitting diode can be realized. In this case, the life of the light emitting diode can be extended, and the options for the light emitting diode that can be used as a system can be expanded.

  It should be noted that the present invention is not limited to those shown in the above-described embodiments, and those skilled in the art can also make changes and applications based on the description in the specification and well-known techniques. Yes, included in the scope of protection.

  The present invention can be configured integrally with a switch part for turning on / off a power input and a drive circuit part for driving a light source, and has the effect of reducing the cost of the entire apparatus and improving workability, and as a light source It is useful as a light emitting diode driving device that drives a light emitting diode to be used, and an illumination device including the same.

The figure which shows the circuit structure of the light emitting diode drive device which concerns on Embodiment 1 of this invention. The figure which shows the circuit structure of the light emitting diode drive device which concerns on Embodiment 2 of this invention. The figure which shows the circuit structure of the switch part of Embodiment 2. The perspective view which shows the external appearance structure of the drive circuit unit containing the light emitting diode drive device which concerns on Embodiment 3 of this invention. The figure which shows schematic structure of the illuminating device containing the light emitting diode drive device of Embodiment 3. FIG. The perspective view which shows the external appearance structure of the drive circuit unit containing the light emitting diode drive device which concerns on Embodiment 4 of this invention. The figure which shows schematic structure of the illuminating device containing the light emitting diode drive device of Embodiment 4. FIG. The figure which shows the external appearance structure of the drive circuit unit containing the light emitting diode drive device which concerns on Embodiment 5 of this invention. The figure which shows schematic structure of the illuminating device containing the light emitting diode drive device of Embodiment 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 DC power supply 2, 2A switch part 3 DC-DC converter 4 Voltage detection circuit 5 Current detection circuit 6, 6A Control circuit part 7, 7A Current control part 8 Light emission part 10 Inrush current reduction circuit 11 Reference current setting part 12 Comparator Unit 13 PWM control unit 14 Driver unit 15 Vf detection unit 16 Base current control unit 18 Delay circuit 19 Resistor 21, 21A, 21B Drive circuit unit 22, 32 Output terminal 23, 31 Input terminal 24 Light emitting diode 25 Heat radiation component 26, 26A , 26B Headlight lamp 27 Input / output terminal 28 External terminal 33 Relay box

Claims (7)

A light-emitting diode driving device that drives a light-emitting diode used as a light source by receiving power supply from a DC power source,
A drive power supply unit including a DC / DC converter that boosts or steps down output power from the DC power supply to a required voltage;
A switch unit configured by the same unit as the drive power supply unit, which opens and closes a power input path from the DC power supply to the drive power supply unit;
A light emitting diode driving device comprising: The light-emitting diode driving device according to claim 1,
An inrush current reducing element connected in series to the output path of the DC / DC converter;
The switch unit includes a first switch that opens and closes a power input path from the DC power source to the drive power source unit, and is closed with a predetermined time delay after the first switch is closed. A light-emitting diode driving device comprising a two-contact relay switch having a second switch to be bypassed. The light-emitting diode driving device according to claim 1 or 2,
An input terminal for inputting a power supply voltage supplied from the DC power supply and a switch signal supplied to the switch unit;
An output terminal that outputs drive power output from the DC / DC converter to a light emitting diode;
The input terminal and the output terminal are light-emitting diode drives that are exposed to the outside in a separate or integral form so that they can be connected to external wiring in a unit housing on which the drive power supply unit and the switch unit are mounted. apparatus. The light-emitting diode driving device according to any one of claims 1 to 3,
A light-emitting diode driving device in which a housing of a unit on which the driving power supply unit and the switch unit are mounted is configured by a resin case. The light emitting diode driving device according to any one of claims 1 to 4,
A light emitting unit connected to the light emitting diode driving device and configured by connecting a plurality of light emitting diodes;
An instrument main body for holding the light emitting diode driving device and the light emitting unit;
A lighting device comprising: The light emitting diode driving device according to any one of claims 1 to 4,
A light emitting unit connected to the light emitting diode driving device, configured by connecting a plurality of light emitting diodes, and disposed in a vehicle cabin;
A vehicle interior lighting device comprising: The light emitting diode driving device according to any one of claims 1 to 4,
A light emitting unit connected to the light emitting diode driving device, configured by connecting a plurality of light emitting diodes, and irradiating light around the vehicle;
A vehicle lighting device comprising:

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