JP2011044678A - Led lighting device for commercial power source - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problem: although there is a growing need for illumination using a commercial power source due to the spread of white LED, many circuit components are required for conversion to a low voltage and for driving the white LED with a constant current, because a driving voltage of the white LED is 4 to 6 volts dependently upon a bandgap voltage of a light-emitting element and must be converted to a low voltage in the case of using the white LED with the commercial power source. <P>SOLUTION: A white LED driving voltage is set to a high voltage near a voltage of the commercial power source, whereby a driving current is reduced and a power source circuit and a driving circuit are simplified. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a configuration in which a driving circuit is simplified by using a high voltage driving light emitting diode in a light emitting diode lighting device using a commercial power source.

A conventional light emitting diode illuminating device for a commercial power source using a light emitting diode has a configuration as shown in FIG. The voltage after full-wave rectification by the diode is stepped down to a voltage close to the driving voltage of the light emitting diode by the switching power supply circuit, then smoothed by a large capacity electrolytic capacitor and supplied to the light emitting diode through the constant current circuit. ing. In this circuit configuration, since the drive current is large, the circuit configuration becomes complicated and a large-capacity electrolytic capacitor is required, which is a major constraint factor for the spread of light-emitting diodes in terms of life.

With the widespread use of white light emitting diodes, there is an increasing need for commercializing small lighting fixtures using commercial power sources. In particular, with the increase in efficiency of white light-emitting diodes, its widespread use is desired because it is overwhelmingly more efficient than incandescent bulbs. Under such circumstances, there is an extremely high need for cost reduction and miniaturization of a light emitting diode drive circuit. For this purpose, in particular, it is necessary to put into practical use a simple drive circuit that does not require the use of large, life-limited parts such as electrolytic capacitors.

Japanese Patent Application No. 2009-35861 Japanese Patent Application No. 2009-132525

Japanese Patent Application No. 2007-84614

Ishizuka Electronics Co., Ltd. CRD (Current Regulative Diode) catalog Cat. No. 113G (issued in April 2009)

The limiting factors for the widespread use of light-emitting diode illuminating devices lie in the large number of power supply components for efficiently driving the light-emitting diodes and large components such as electrolytic capacitors, which have limited lifetime. The number of parts is increased in order to reduce the voltage from the commercial voltage to the driving voltage of the light emitting diode, stabilize the voltage, and supply a constant current. The driving voltage of the light emitting diode is determined by the band gap voltage of the light emitting element, and cannot be driven at a higher voltage. If there is a light-emitting diode that operates at a high voltage, it can be driven from a commercial AC power supply through a simple power supply circuit such as a rectifier circuit, and the drive current can be reduced accordingly. It can be simplified. In addition, since the drive current is reduced, a circuit can be configured with a small-capacitance capacitor, so that a film capacitor or a ceramic capacitor with no lifespan can be used instead of an electrolytic capacitor with a limited lifespan. Become. However, practically, such a light emitting diode operating at a high voltage has not been put into practical use.

In order to respond to such problems and needs, the present invention uses a light emitting diode that is driven at a high voltage near the commercial power supply voltage to simplify and drive a high-voltage power supply circuit formed from the commercial power supply. The constant current circuit is simplified by reducing the current. As a result, a light-emitting diode illuminating device that is low in cost and has no limitation on the lifetime is realized.

As a high-voltage light-emitting diode, an element that can be driven at a high voltage is realized by forming a number of electrically isolated light-emitting parts on the substrate on which the light-emitting diode is formed and connecting them in series in multiple stages. Yes (see Patent Document 1). For example, it is possible to configure a light emitting element that operates at 90 volts by configuring 20 light emitting elements with a driving voltage of 4.5 volts in series. In this manner, a high voltage drive light emitting diode element can be realized. The drive current is a current for driving one light emitting unit, and the drive current for obtaining the same luminance can be lowered by the number of stages connected in series. With 20 stages of series connection, the drive current can be dramatically reduced to 1/20. That is, in the light emitting diodes of the 20 light emitting elements connected in series, the driving voltage is 20 times and the driving current can be reduced to 1/20.

In the configuration of the present invention, it is possible to configure a direct current power supply with a simple circuit from a commercial power supply by driving the light emitting diode to a high voltage, and the number of parts of the power supply circuit can be greatly simplified. In addition, the lower drive current eliminates the need for large components such as electrolytic capacitors for power supply stabilization, and the use of small components such as film capacitors and ceramic capacitors that do not have a limited lifespan. It becomes possible. At the same time, by reducing the drive current, the constant current circuit can be a simple constant current circuit such as a junction FET constant current element, and the number of components can be greatly reduced (see Patent Document 2 and Non-Patent Document 1). reference). Further, even when a switching power supply is used as the power supply, the drive current is reduced, so that it can be realized with a simple circuit.

Since the light-emitting diode illumination system of the present invention can be driven by a simple power supply system, it can be reduced in size and cost, and a high-efficiency light-emitting system possessed by the light-emitting diode can be provided in a small size at low cost. . Further, by eliminating the use of an electrolytic capacitor and eliminating the restriction on the life of the power supply circuit components, the characteristics of the long-life light emitting diode can be exhibited. In the future, the present invention will have a significant impact on the industry when light-emitting diodes with high luminous efficiency are used in place of energy savings to replace household lamps.

  Circuit diagram of a light-emitting diode illuminating device using a conventional commercial power supply   The circuit block diagram of the light-emitting-diode illuminating device using the commercial power source of this invention   Another embodiment of FIG. 2 (see Patent Document 1)   Configuration diagram of high voltage drive light emitting diode   Junction FET type constant current circuit diagram and characteristic diagram   Configuration and mounting diagram of junction FET type constant current circuit according to the present invention   Operational explanation of small pulsation full-wave rectifier circuit from commercial power supply in FIG.   Examples of specifications and specifications of lighting equipment using high-voltage light-emitting diodes

The circuit configuration of the light-emitting diode illuminating device of the present invention is shown in FIG. 2-a is a block diagram, and FIGS. 2-b, 2-c and 2-d are circuit diagrams. 2B, 10 is an AC power source, 11 is a fuse, 12 is a phase control circuit, 13 is a full-wave rectifier circuit A, 14 is a full-wave rectifier circuit B, 15 is a waveform synthesis circuit, 16 is a constant current circuit element, 17 Indicates a high voltage drive light emitting diode. The adoption of the high voltage drive light emitting diode 17 makes it possible to simplify the power supply circuit from the commercial power supply, and the simple constant current element 16 can be adopted by reducing the drive current. The voltage output waveform of the full-wave rectifier circuit B14 generates a full-wave rectified voltage delayed by 90 degrees by the phase control circuit 12 with respect to the output voltage waveform of the full-wave rectifier circuit A13. This waveform is rectified while pulsating at a frequency four times that of a commercial AC power supply. Since the driving current is small, the capacitor of the phase control circuit 12 can be a film capacitor or a ceramic capacitor. Details of the voltage waveform are shown in FIG.

FIG. 2C shows an example in which an inductor is used as the phase control circuit from the embodiment of FIG. In an example in which 200 volts is used as a commercial power supply, it is often advantageous to use an inductor as shown in FIG. The voltage waveform of the circuit will be described with reference to FIG. 7. In the case of using a full-wave rectification, the phase is delayed by 90 degrees from the commercial power source when using a capacitor, and the phase is advanced by 90 degrees when having an inductor. This 90 degree delay and advance result in the same operation and the same effect is obtained.

FIG. 2D shows an example in which a switching power supply is added to the power supply circuit to reduce the heat loss in the constant current element and the efficiency of the power supply power is improved with respect to the embodiment of FIG. Since the drive current is reduced by the high-voltage driven light emitting diode, the switching power supply is configured by a simple switching power supply 39 that switches the MOS transistor 42 for flowing the current to the load side at a high speed and smoothes it by the capacitor Co44. Can do. The fact that the drive current is greatly reduced is an advantage that can be configured with such a simple circuit. Further, in this example, the constant current circuit 37 is configured using a MOS transistor which is the same component as the switching circuit. This is a constant current circuit having a known current mirror configuration. The operation of this part is performed following the description of FIG.

FIG. 3 shows another embodiment of the present invention. The block diagram is shown in FIG. 3-a, and the circuit diagram is shown in FIGS. 3-b and 3-c. 3B, 50 is a commercial power source, 51 is a fuse, 54 is a full-wave rectifier circuit A, 55 is a full-wave rectifier circuit B, 58 is a phase control circuit, 66 is a waveform synthesis circuit, 67 is a constant current circuit element, 68 Is a high voltage drive light emitting diode. The voltage between 56 points and 77 points, which is the output of the full wave rectifier circuit A, and the voltage between 59 points and 60 points, which is the output of the full wave rectifier circuit B, are full wave rectified voltages having the same phase, and the resistance output of the phase control circuit. The voltage between 63 points and 64 points is in phase with it, and the voltage between 61 points and 62 points of the capacitor output is delayed by 90 degrees. Thereby, the voltage waveform 65-64 point voltage after waveform synthesis becomes as shown in FIG. Details of this portion will be described with reference to FIG. The avalanche diode in the phase control circuit 58 has a breakdown voltage of 40 volts and reduces the breakdown voltage of the ceramic capacitor. This is not always necessary when using a capacitor with a withstand voltage. FIG. 3C shows an example in which the full wave rectifier circuit is doubled to single with respect to FIG. 3B to obtain the capacitive drive and resistance drive of the phase control circuit from the same full wave rectifier circuit 70. 71 is a phase control circuit, and 72 is a waveform synthesis circuit.

A high voltage light emitting diode used in the present invention is shown in FIG. FIG. 4-a is a plan view of the element. Reference numeral 81 denotes a high voltage drive light emitting diode, which shows a state in which 20 optical microcells are connected in series (see Patent Document 1). Each light microcell is a light emitting element, and the drive voltage is 4.5 volts in this case. In this example, it is composed of optical microcells separated into 4 columns × 5 rows, and shows a state in which they are connected in series to constitute one light emitting element, 81 is a P-type terminal, and 82 is an N-type. Terminals are shown. The driving voltage Vd of the high voltage driving light emitting diode is 20 volts in series with 20 light emitting elements. The drive current is a current value for driving the light emitting element of one optical microcell. In order to obtain the same luminance, the conventional light emitting diode can be reduced to 1/20. In FIG. 4-b, 83 shows the equivalent circuit diagram.

FIG. 4C shows a cross-sectional view of the light emitting diode mounted on the package. Reference numeral 84 denotes a light emitting diode having sapphire as a substrate, and 85 and 86 are schematic views of simplified sectional views of the optical microcell light emitting element. The light emitting element is a GaAlN semiconductor, and 87 is a light emitting active layer of the light emitting element portion. This figure shows a state in which the two elements 85 and 86 are separated on the sapphire substrate, but actually the elements are separated and arranged on a matrix of 4 columns × 5 rows as shown in FIG. (See Patent Document 1). The individual elements are wired on the sapphire substrate so that they are connected in series with each other. In the circuit diagram, 81 and 82 are taken out through the flip chip bump electrodes 88 and 89, and are connected to the conductor electrodes 91 and 91 on the package substrate 90. 92 is taken out of the package. This is sealed by a side wall 93 and a cap 94 of the package. The light from the light emitting part is irradiated on the phosphor 95 through the sapphire substrate, and is collected in the direction of the light collecting direction 96 as light having a long wavelength. In the case of using this package, in order to improve the light emission efficiency, a light emitting element is formed on a sapphire substrate, light is emitted from the back surface of the element, an electrode is taken out from the element surface, and mounted by flip chip electrode technology (patent) Reference 1). This configuration reduces the thermal resistance. In this case, the thermal resistance is as low as 5 ° C./watt. Even though light-emitting diodes for lighting are efficient, they generate heat of several watts, so a package with low thermal resistance and mounting technology are required. This example uses a mounting method that suits its purpose.

According to the high voltage driving light emitting diode of this configuration, in the case of a 4.5 watt light emitting diode, a driving current of 1 ampere is required when using a 4.5 volt light emitting diode with a normal driving voltage. The high voltage drive light-emitting diodes connected in series in 20 stages according to the invention are characterized in that the drive voltage Vd is 90 volts and the drive current is as low as 1/20, 50 milliamperes.

FIG. 5 shows the configuration of a constant current element used in the present invention. By reducing the drive current, a constant current element can be used instead of the constant current circuit. FIG. 5A shows a circuit diagram of the junction FET. It is known that a constant current can be obtained between the drain and the source by connecting the gate of the FET having a negative threshold voltage to the source. A constant current characteristic is obtained at an applied voltage Vf or higher which becomes a constant current (see Patent Document 2 and Non-Patent Document 1). Vf is usually a small value of about 1 volt or less. The voltage-current characteristic is shown in FIG. The direction in which the applied voltage is positive is determined by the threshold voltage, electron mobility, and element size. For the direction in which the applied voltage is negative, the diode has a forward current characteristic due to the parasitic diode inside the element. Further, the element size of this junction FET is a small silicon element of about 0.5 mm × 0.5 mm as shown in FIG. 5C, and a structure in which a drain is taken out from the front surface and a source / gate is taken out from the back surface is general. This is sealed in a general-purpose mold package. (See Non-Patent Document 1)

The junction FET type constant current circuit is sealed in a small general-purpose diode package, and a circuit having a driving capability of about 10 milliamperes has been put into practical use. It is put into practical use under the trade name CRD (see Non-Patent Document 1). However, the light emitting diode used for illumination requires about 5 watts, and the drive current needs about 50 milliamperes. For this reason, it is necessary to use a plurality of general-purpose package products. Further, the constant current value of the junction FET has two problems, that is, the constant current value usually varies by about 10% due to the variation in the manufacturing process and the constant current value changes due to heat generation due to the large temperature coefficient. When using a plurality, the current value can be selected and combined to reduce the total tolerance, but it is complicated to select and use the CRD product.

FIG. 6 shows the structure of a junction FET used in the present invention in which this poor characteristic is improved. 6A shows a circuit diagram in which a plurality of general-purpose junction FETs are used in parallel. In this configuration, four elements are used for each of the drain 1 and the drain 2. 6B shows the structure of the power package 100 used in the present invention. Reference numerals 101 and 106 denote drain 1 terminals, and 103 and 104 denote drain 2 terminals. The drains 1 and 2 are connected and used at the time of mounting. Reference numerals 102 and 105 denote source / gate electrodes. This package has a heat sink like 107 and has a low thermal resistance of 20 ° C./W. FIG. 6C is a perspective view showing a state in which eight elements, that is, eight elements a, b, c, d, e, f, g, and h are mounted. In order to obtain 50 mA with a constant current, the constant current value of each element is 6.25 mA. An element h 108 is one of them. The element has a bonding pad formed on the surface and serves as a drain electrode. The back side is a common electrode for the source and drain, and is plated with gold so that it can be easily connected to the substrate. All the elements are die-bonded to the lead frames 102 and 105, and the source and gate of all the elements are connected to the lead frames 102 and 105 through the substrate of each element. The drains of the elements a, b, c, and d are connected to the lead frames 101 and 106 by wire bonds, and the drains of the elements e, f, g, and h are connected to the lead frames 103 and 104 by wire bonds. By connecting the lead frames 101 and 106 and the lead frames 103 and 104 on the mounting substrate, the drains of eight elements a, b, c, d, e, f, g, and h are connected to one. These elements are small silicon elements of 0.3 mm × 0.3 mm meters, and when the elements are die-bonded from the wafer, the constant current values of the individual elements are measured in advance so that the necessary total constant current values are obtained. It is possible to mount a combination of elements. In this way, by combining elements whose characteristics are known on the wafer, even if there is a variation of 10% in tolerance among elements, it is possible to easily make a tolerance of 1% by combining eight elements. At the stage of use, a high-precision junction FET can be realized. FIG. 6-d is an equivalent circuit diagram thereof.

By using a package with a low thermal resistance as shown in FIG. 6B and dividing the FET element, the heat transfer from the element to the lead frame can be dispersed, the thermal resistance to the heat sink can be divided, and the temperature of the element can be increased. Can be suppressed. Thus, by adopting a multi-chip mounting system as a constant current element, many merits such as a reduction in tolerance and a reduction in thermal resistance can be created. Thus, the junction FET type constant current element used in the present invention simultaneously compensates for the weak point that the characteristic tolerance is large and the large temperature dependency.

The characteristics of the junction FET type constant current element used in FIGS. 2B, 2C, 3B, and 3C as in this example are as follows: 50 mA current drive, 30 V average voltage drop. The temperature rise in the 20 ° C./watt package can be suppressed to about 30 ° C. for a heat generation of 5 watts. If it is this level, the temperature coefficient of a constant current will not become a big problem practically.

FIG. 7 shows an example of specific power supply voltage waveforms and operating points according to the configuration of the present invention. FIG. 7 is a diagram for explaining how the operation of the full-wave small pulsation rectifier circuit is formed from the commercial power supply of FIG. FIG. 7A shows the input voltage signal of the full-wave rectifier circuit A13 of FIG. 2-B, the waveform of the A waveform and its negative phase voltage, and the B waveform. The higher voltage on the positive voltage side of both waveforms, that is, the ridge line The voltage is the output voltage of the full-wave rectifier circuit A13, which is the E waveform in FIG. 7B shows the input voltage signal of the full-wave rectifier circuit B14 of FIG. 2-B, that is, the output voltage of the phase control circuit, the C waveform and its opposite phase voltage, and the D waveform. The voltage, that is, the ridge line voltage, is the output voltage of the full-wave rectifier circuit B14, and has the F waveform in FIG. The output related to FIG. 7B is a waveform whose phase is delayed by 90 degrees with respect to FIG. FIG. 7-c shows the input voltage waveform of the waveform synthesis circuit, that is, the output of the full-wave rectifier circuit A, the output of the full-wave rectifier circuit B that is 90 degrees behind the waveform E, and the waveform F. The ridge voltage is the output voltage of the waveform synthesis circuit. FIG. 7-d shows the waveform, G waveform. This voltage waveform pulsates between Vmax and Vmin according to a trigonometric function. When the commercial power source is AC 100 volts, it is a known fact that Vmax is 141 volts. Vmin is 100 volts. This can be easily calculated from the point where the output values of sine (SIN) and cosine (COS) having Vmax as a vertex coincide.

This voltage waveform is a voltage between 25 and 24 in FIG. 2B and is applied to the constant current circuit 16 and the high voltage light emitting diode 17. Similarly, the voltage between 33 and 31 in FIG. 2-c, the voltage between 45 and 35 in FIG. 2-d, the voltage between 65 and 64 in FIG. 3-b, The voltage applied between the high voltage light emitting diode between 79 points and 76 points and the constant current circuit. By setting this voltage to a voltage obtained by adding the driving voltage Vd (90 volts) of the high voltage driving light emitting diode and Vf (about 0.5 volts) of the constant current element, that is, Vd + Vf or more, stable light emission can be achieved. .

The above voltage waveforms have been described with reference to the phase control circuit using the capacitor of FIG. 2-a, but the operation of the phase control circuit using the inductor as shown in FIGS. 2-c and 2-d is similar. The 7-d G waveform is exactly the same. When phase control using an inductor is performed instead of phase control using a capacitor, the waveform diagram corresponding to FIG. 7B is 90 degrees behind the phase of FIG. 7A, but 90 degrees behind and 90 degrees ahead. The difference is 180 degrees, and since the full-wave rectification waveform is used, the difference is completely eliminated. Detailed explanation is omitted because it is easy to understand.

Thus, since Vmin is always larger than Vd + Vf, the light emitting diode is always lit. When Vmin is smaller than Vd + Vf, the light emitting diode is lit at a frequency four times the AC frequency of the commercial power supply. Although this is not a problem in terms of illumination, it is generally not preferable because flickering occurs in synchronization with the driving cycle of an electronic camera or the like and many disadvantages occur in practice.

A method using a simple constant current element as a constant current circuit as in the case of FIGS. 2-b, 2-c, 3-b, and 3-c is optimal for cost reduction and miniaturization. However, when the drive voltage is Vd + Vf or more, the voltage is wasted to drive the light emitting diode, that is, when the voltage is Vd + Vf or more, power is consumed in the constant current circuit. For this purpose, it is desirable that the voltage difference between Vmax and Vd + Vf be as small as possible. The power supply circuit of the present invention has a simple circuit configuration and can substantially reduce the difference between Vmax and Vmin. It is a great feature for a configuration aimed at low cost and miniaturization.

On the other hand, it may be desired to improve the power supply efficiency as much as possible in the case of an application pursuing the illumination efficiency of the light emitting diode. Although the configuration is a little more complicated than in FIG. 2B, the drive current is reduced while the drive current is reduced by using the high-voltage drive light emitting diode, which is a feature of the present invention, and the power supply circuit is simplified. FIG. 2D shows a simple configuration of the switching power supply and the constant current circuit, taking advantage of the above feature.

In FIG. 2D, the switching power supply is operated so that the driving voltage of the constant current circuit becomes the minimum voltage necessary for the constant current operation. In this example, a constant current drive voltage, 49-point voltage Vi, is set to operate at 1.5 ± 0.2 volts. When Vi is higher than 1.5 volts, the MOS transistor 41 is turned off and the power supply MOS transistor 42 is turned off to stop the supply of the applied voltage. As a result, the constant current is supplied by the accumulated charge of the smoothing capacitor Co44. As a result, when Vo and Vi drop and Vi drops below 1.5 volts, the MOS transistor 41 is turned on, the power supply MOS transistor 42 is turned on to supply the power supply voltage, and the constant current supply and smoothing are performed. The capacitor Co44 is charged. As a result, when Vo and Vi rise and Vi becomes higher than 1.5 volts again, the MOS transistor is turned off. This is one cycle. The main factor that determines this period is the 48-point time constant determined by the resistors r6 and Cd. In this case, V ₀ oscillates at a frequency of 10 μS and a frequency of 100 KHz. Voltage amplitude its frequency is determined by the value of the constant current value and the V ₀ voltage smoothing capacitor Co44. Thus, in this example, the amplitude value is 0.2 volts and the frequency is 100 kHz.
The V ₀ point voltage oscillates at Vd + 1.5 ± 0.2 volts.

In this way, Vi is controlled with an amplitude of about 0.2 volts centered on 1.5 volts, and heat loss in the constant current circuit can be minimized. The heat loss is very small at 75 milliwatts at 50 milliamperes × 1.5 volts, and the heat loss is negligible compared to the power consumption in the light emitting diode. Further, if such high-speed switching is performed, the capacitor 44 may be 1 μF or less, so that a film capacitor or a ceramic capacitor having no limit in life can be used. It is an extremely efficient switching power supply circuit.

The operation of the constant current circuit in FIG. The constant current circuit can be easily made by the current mirror circuit 37 of the MOS transistor, the ratio of the sizes of the MOS transistors constituting the mirror circuit, and the resistance value r1 of the resistor 38. The power supply 40 for determining the power supply of the comparator and the reference voltage 46 is a simple power supply circuit and forms 5 volts.

Although FIG. 2D shows a constant current circuit and a switching power source using MOS transistors as examples, a general-purpose circuit can be easily configured. In any circuit configuration, since the drive current is reduced, the circuit can be simplified and downsized.

As shown in FIG. 7-d, in the case of AC 50 Hz, one cycle is 20 milliseconds, and the output waveform pulsates at a quarter of that, 200 Hz, but the light emitting diode emits light stably and statically. To do. When dimming is required, the amount of light can be easily adjusted by driving the entire high-voltage light-emitting diode at a frequency higher than this pulsation frequency and changing the duty ratio at a high frequency that does not affect other devices. Can do. Since this technique is a known technique not directly related to the present invention, it will not be mentioned.

In FIG. 8, the example of the design value of the application example of this invention is shown. FIG. 8A shows a specification example of the characteristic value. The commercial power supply is 100 VAC, the frequency of the power supply is 50 Hz, the applied voltage of the light emitting diode is 90 volts, and the light emitting diode is formed by 20 stages of 4.5 volt drive in series. The driving constant current value is 50 milliamperes, and the power consumption is 4.5 watts.

FIG. 8B shows specifications in the case of the circuit diagram 2-b of the present invention under these conditions. Light emitting diode heat generation is 4.5 watts, and constant current element heat generation is about 1 watt. The thermal resistance of the light emitting diode package is 5 ° C./W, the device temperature is as low as 22.5 ° C. with respect to the ambient temperature, the thermal resistance of the constant current device is 20 ° C./W, and the device temperature is the ambient temperature. On the other hand, the temperature rise is as low as 30 ° C., and it can be stably used as a light emitting system using a commercial power source.

In the case of FIG. 2D using a switching power supply, the heat loss of the constant current portion is as extremely small as 75 milliwatts. Therefore, the overall efficiency of the light emitting diode illumination device can be improved. Whether to adopt the configuration of FIG. 2-b or the configuration of FIG. 2-d depends on the purpose in terms of cost, size, and efficiency.

In this case, 100 V is used as the commercial power source, but the same configuration can be adopted for commercial power sources having other voltages. For example, for 200V, a light-emitting diode of a 180 volt specification can be realized by changing the number of light-emitting diode optical microcells from 20 to 40, and a similar effect can be created by using this.

Industrial applicability

Applications of light emitting diodes are expanding for energy saving. According to the present invention, the fact that the drive circuit can be simplified and reduced in size by using a high-voltage driven light emitting diode further promotes the popularization of the light emitting diode in order to save energy in the lighting fixture. In particular, the practical use of low-power consumption, small-sized and long-life light-emitting sources is extremely important in applications where light bulbs are used in closed spaces where importance is placed on the replacement of small-sized light bulbs that support E17 caps and the design of lighting equipment. It is what you have.

DESCRIPTION OF SYMBOLS 1 ... Commercial power supply 2 ... Fuse 3 ... Diode bridge 4 ... Switching power supply 5 ... Electrolytic capacitor 6 ... Constant current circuit 7 ... Light emitting diode 10 ... Commercial power supply 11. ..Fuse 12 ... Phase control circuit 13 with capacitor 13 ... Diode full-bridge full-wave rectifier circuit A
DESCRIPTION OF SYMBOLS 14 ... Diode full bridge full wave rectifier circuit B 15 ... Waveform synthesis circuit 16 ... Constant current element 17 ... High voltage drive light emitting diode 27 ... Phase control circuit by inductor 36 ... High voltage Driving light-emitting diode 37 ... constant current circuit 39 ... switching power supply circuit 41 ... MOS transistor 42 ... P-type MOS transistor 44 ... smoothing capacitor Co 47 ... comparator 50 ... commercial power supply 51 ... Fuse 54 ... Diode full bridge A
55 ... Diode full bridge B
58... Phase control circuit using capacitors and resistors 66... Waveform synthesis circuit 67... Constant current element 68... High-voltage drive light emitting diode 69 ... Avalanche breakdown diode 70. .... Simple phase control circuit 72 ... Waveform synthesis circuit 73 ... Constant current element 74 ... High voltage drive light emitting diode 80 ... Plan view of light emitting diode element 83 ... Circuit of high voltage drive light emitting diode 84... High voltage drive light emitting diode elements 85, 86... GaAlN light emitting element 87... Active layer 88 of light emitting element, 89... Flip chip bump 90. Package electrode 93 ... Package side wall 94 ... Cap 95 ... Phosphor 100 ... Power packages 101, 106 ..Drain terminal lead frames 102 and 105... Source and gate terminal lead frames 103 and 104... Drain terminal lead frame 107... Heat sink 108. body

Claims (6)

A light-emitting diode illuminating device using a commercial power source, comprising a light-emitting diode driven by a high voltage, a full-wave rectifier circuit, a phase control circuit, a waveform synthesizing circuit, and a constant current circuit. The light-emitting diode illuminating device according to claim 1, comprising a light-emitting diode driven at high voltage, a full-wave rectifier circuit, a phase control circuit, a power supply circuit using a waveform synthesis circuit, and a junction FET constant current element In a light-emitting diode illuminating device using a commercial power supply, a high-voltage driven light-emitting diode and one junction FET or a combination thereof, or a junction FET type constant current circuit in which a plurality of junction FET elements are mounted in one package and some AC A light-emitting diode illuminating device comprising a smooth power supply circuit for a power supply A light-emitting diode illuminating device, wherein a switching power supply is added to the power supply circuit according to claims 1, 2, and 3. In a light-emitting diode illuminating device using a commercial power supply, in a light-emitting diode illuminating device using a junction FET type constant current element as a constant current circuit, a plurality of junction FET elements are mounted in the same package. A light-emitting diode illuminating device using the element. In a light-emitting diode illuminating device using a commercial power supply, a power supply circuit comprising a full-wave rectifier circuit using a diode as a power supply circuit, a phase control circuit using a capacitor or an inductor, and a waveform synthesis circuit for synthesizing a full-wave rectifier circuit output / phase control circuit output Light emitting diode lighting device used

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