JP6168941B2 - LED lighting device - Google Patents

Description

  The present invention relates to an LED lighting device that uses an LED as a light source and has a mode in which light is emitted at low illuminance and a mode in which light is emitted at high illuminance.

  Lighting devices that can switch between nightlight and normal lighting have been known for a long time. The night light is dark and reddish, and the normal light is bright white. Since this illuminating device is different in light emission color between low illuminance and high illuminance, it can be generalized as an illuminating device in which dimming and toning are linked. For example, Patent Document 1 discloses a color temperature variable illumination device that includes a plurality of light sources having different emission colors, adjusts the ratio of the amount of emitted light of each light source, and can reduce the total amount of emitted light as the color temperature decreases. It is shown.

  Recently, with the widespread use of lighting devices using LEDs as light sources, there has been a demand for lighting devices capable of switching between nightlight and normal lighting using LEDs as light sources. Simply prepare the LED light source and drive circuit for nightlight and the LED light source and drive circuit for normal illumination and combine them into a single lighting device to obtain the desired LED lighting device. It is convenient if the colors are linked.

  For example, in FIG. 1A of Patent Document 2, a red light emitting diode 3R, a green light emitting diode 3G, and a blue light emitting diode 3B are mounted on one illumination light source 3, and each red light green, Illustrated is an illuminating device including a power supply unit 2 that independently controls light emission of blue light emitting diodes 3R, 3G, and 3B. As shown in FIG. 1B of Patent Document 2, the power supply unit 2 drives a control signal input unit 20, an AC / DC conversion unit 21, and red, green, and blue light emitting diodes 3R, 3G, and 3B, respectively. A red LED drive unit 22R, a green LED drive unit 22G, a blue LED drive unit 22B, and a drive signal conversion unit 23. At this time, the control signal input unit 20 passes the control signal to the drive signal conversion unit 23. The AC / DC converter 21 extracts power from the commercial power source and supplies the power to the red, green, and blue LED drive units 22R, 22G, and 22B and the drive signal converter 23.

  This lighting device controls the light emission of the red, green, and blue light emitting diodes 3R, 3G, and 3B independently by the control signal relating to the light control obtained from the controller 1. Note that the driving conditions of the red, green, and blue light emitting diodes 3R, 3G, and 3B are set in advance for the control signal related to the light control. As a result, the lighting device can perform color adjustment in conjunction with light adjustment. By the way, this lighting device approximates the light quantity-color temperature characteristic of an incandescent bulb, and the color temperature is low (reddish) at low illuminance, and the color temperature is high (whited) at illuminance.

JP-A-4-296491 (paragraph 0005) JP2013-168383A (FIG. 1)

The LED illumination device as disclosed in Patent Document 2 uses a plurality of light sources (red, green, and blue light emitting diodes 3R, 3G, and 3B) as separate power sources (red, green, and blue LED driving units 22R and 22G). 22B). In addition, in such an LED lighting device, it is necessary to set driving conditions for each light source in advance according to dimming (total light amount) data and store the driving conditions in a control unit (driving signal conversion unit 23) or the like. . During driving, this condition must be read to generate a driving signal for each light source. That is, such an LED lighting device has a problem that a circuit configuration and a control system become complicated.

  Therefore, the present invention has been made in view of the above problems, and is a low-illuminance emission mode that emits light in the first emission color as dark as a nightlight and a light emission that emits light in the second emission color as in normal illumination. An object of the present invention is to provide an LED lighting device having a mode and a simple circuit configuration and control.

In order to solve the above-described problems, the LED lighting device of the present invention includes a first LED array in which a plurality of LEDs are connected in series in an LED lighting device that emits light with low illuminance and light emission with high illuminance. 2 LED rows, and a power supply circuit having one output terminal for applying a voltage to the first LED rows and the second LED rows, and the plurality of LEDs include at least a first LED that emits light in a first emission color and a second LED. A second LED that emits light in an emission color is included, and the first LED row is different in emission color from the second LED row, and when the voltage output from the power supply circuit is low, only the first LED row is lit; The number of the LEDs included in one LED row is less than the number of the LEDs included in the second LED row, and a current limiting circuit is connected in series to the first LED row, and the plurality of LEDs The LED die mounted on one module substrate and included in the first LED is covered with a first fluorescent member on the upper surface, and the LED die included in the second LED is covered with a second fluorescent member on the upper surface. The first fluorescent member is a variable voltage source in which the first fluorescent member is connected between the LEDs, the second fluorescent member is connected between the second LEDs , and the power supply circuit can change an output voltage, and the first LED row And the second LED string are connected in series to the power supply circuit, and a bypass circuit is provided at a connection portion of the first LED string and the second LED string, and the bypass circuit is cut according to a current flowing through the second LED string. It is turned off .

  The LED lighting device of the present invention includes a low illumination emission mode in which only the first LED array emits light and a high illumination emission mode in which both the first LED array and the second LED array emit light, and light emission is performed in the low illumination emission mode and the high illumination emission mode. The color is different. At this time, the power supply circuits that supply power to the first LED array and the second LED array are common, and further, power is supplied from the common output terminal to the first LED array and the second LED array. The switching between the low illuminance light emission mode and the high illuminance light emission mode is controlled by the voltage of the output terminal of the power supply circuit. That is, the LED illumination device of the present invention switches between the low illuminance light emission mode and the high illuminance light emission mode by the output voltage of one output terminal of one power supply circuit, so that the circuit configuration and control are simplified.

Wherein said 1LED is arranged at the center of the module substrate, the observed first 2LED takes the first 1LED circumference, said first 1LED is surrounded by the first dam member of circular, said first 2LED and the first dam member Is surrounded by a circular second dam material, and the bypass circuit may be disposed on the module substrate and surrounded by a rectangular third dam material and a part of the second dam material.

  Even if the color temperature of the light emission color of the first LED is lower than the color temperature of the light emission color of the second LED, the proportion of the first LED included in the first LED row is greater than the proportion of the first LED included in the second LED row. good.

  As described above, the LED illumination device of the present invention switches between the low illuminance light emission mode and the high illuminance light emission mode according to the output voltage of one output terminal of one power supply circuit, so that the circuit configuration and control are simplified.

The LED lighting apparatus shown as 1st Embodiment of this invention. The circuit diagram which made the light emission part block in the circuit diagram of FIG. Sectional drawing of the light emission part of FIG. The LED lighting apparatus shown as 2nd Embodiment of this invention. The circuit diagram which made the light emission part block in the circuit diagram of FIG. Sectional drawing of the light emission part of FIG.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. In the description of the drawings, the same or equivalent elements will be denoted by the same reference numerals, and redundant description will be omitted. Moreover, the relationship with the invention specific matter described in the claims is described in parentheses.

(First embodiment)
The LED lighting device 100 shown as the first embodiment of the present invention will be described with reference to FIGS.

  First, the circuit configuration of the LED lighting device 100 will be described with reference to FIG. FIG. 1 is a circuit diagram of the LED lighting device 100. In FIG. 1, a constant current driver 101 (power circuit) included in the LED lighting device 100 has a control signal input terminal 102 to which a control signal 102a for setting a current value to be output is input and a power input to which a power line 103a is connected. There are a terminal 103, a ground terminal 104 that is the ground level 104a of the control signal 102a and the power line 103a, an output terminal 105 that outputs a current to the load, and a current feedback terminal 106 from which the current returns from the load.

  A plurality of LEDs 108a (first LEDs) are connected in series to form a first LED row 108, and similarly, a plurality of LEDs 109a (second LEDs) constitute a second LED row 109. Both the anode of the first LED array 108 and the anode of the second LED array 109 are connected to the output terminal 105 of the constant current driver 101. Note that the number of LEDs 108 a included in the first LED array 108 is smaller than the number of LEDs 109 a included in the second LED array 109. The cathode of the first LED array 108 is connected to the current feedback terminal 106 of the constant current driver 101 via a current limiting circuit 110 including a depletion type FET 111 (hereinafter referred to as FET) and a resistor 112, and the cathode of the second LED array 109 is directly connected. Specifically, it is connected to the current feedback terminal 106 of the constant current driver 101. In the current limiting circuit 110, the drain of the FET 111 is connected to the cathode of the first LED string 108, the source is connected to the right terminal of the resistor 112, and the gate is connected to the left terminal of the resistor 112 and the current feedback terminal 106 of the constant current driver 101. ing.

Next, light emission and circuit blocks included in the LED lighting device 100 shown in FIG. 1 will be described. The LED 108a emits light at a color temperature (first emission color) of 2700K, and the LED 109a emits light at a color temperature (second emission color) of 5400K. That is, when operating in the low-illuminance light emission mode like a night light, only the first LED array 108 is lit, and the emission color becomes the reddish first emission color. On the other hand, the first LED array 108 when operating in the high-illuminance emission mode as in normal illumination.
And the second LED array 109 emit light, and the emission color is bluish white. Note that the emission color in the high-illuminance emission mode is lower than 5400K because the emission of the first LED array 108 and the emission of the second LED array 109 are mixed.

  As described above, the number of LEDs 108a is smaller than the number of LEDs 109a. Therefore, the threshold value Vth1 of the first LED array 108 configured by connecting LEDs 108a in series is smaller than the threshold value Vth2 of the second LED array 109 configured by connecting LEDs 109a in series. The threshold value of the first LED string 108 is the product of the forward voltage drop of the LED 108a and the number of series stages thereof. Similarly, the threshold value of the second LED string 109 is the product of the forward voltage drop of the LED 109a and the number of series stages thereof.

  In the current limiting circuit 110, if the voltage Vgs between the gate and the drain of the FET 111 is higher than the threshold value of the FET 111, the current Ids flows between the source and the drain. In the current limiting circuit 110, the maximum current Imax that can be passed through the current limiting circuit 110 is determined from the relationship between the voltage Vgs and the current Ids and the voltage drop of the resistor 112 due to the current Ids. The current limiting circuit 110 can be replaced with another current limiting circuit such as a constant current diode.

  Finally, the overall operation of the LED lighting device 100 shown in FIG. 1 will be described. In the low illuminance light emission mode, the constant current driver 101 outputs a current I smaller than the maximum current Imax of the current limiting circuit 110 from the output terminal 105. At this time, all the current I flows through the first LED array 108, and the voltage V of the output terminal 105 becomes slightly larger than the threshold voltage Vth1 of the first LED array 108.

  On the other hand, the constant current driver 101 outputs a current I larger than the maximum current Imax of the current limiting circuit 110 from the output terminal 105 in the high illuminance light emission mode. At this time, a part of the current I flows through the first LED array 108 and the remaining part flows through the second LED array 109. The value of the current flowing through the first LED array 108 is the current Imax, and the voltage V at the output terminal 105 is slightly larger than the threshold value Vth2 of the second LED array 109. The LED lighting device 100 may be dimmed by adjusting the setting of the current I in the high illuminance light emission mode.

  As described above, the LED lighting device 100 includes the low illuminance light emission mode in which only the first LED row 108 emits light and the high illuminance light emission mode in which both the first LED row 108 and the second LED row 109 emit light. The emission color is different in the illuminance emission mode. At this time, the constant current driver 101 (power supply circuit) that supplies current (power) to the first LED array 108 and the second LED array 109 supplies current from the output terminal 105 to the first LED array 108 and the second LED array 109. The constant current driver 101 switches between the low illuminance light emission mode and the high illuminance light emission mode with the current I, but the output voltage V is adjusted for each of the low illuminance light emission mode and the high illuminance light emission mode to make the output current constant. Therefore, it can be said that each light emission mode is controlled by the output voltage V.

  As described above, since the LED lighting device 100 switches between the low illuminance light emission mode and the high illuminance light emission mode only by the output voltage V of the one output terminal 105 of the constant current driver 101, the circuit configuration and control become simple. ing.

Next, the light emitting unit of the LED lighting device 100 shown in FIG. 1 will be described with reference to FIG. FIG. 2 is a circuit diagram showing the light emitting unit of the LED lighting device 100 and the current limiting circuit 110 as a block. The light emitting unit is a circuit including the first and second LED rows 108 and 109 in FIG. In FIG. 2, the output terminal 105 of the constant current driver 101 is connected to the electrode 114 of the LED module 113 which is a light emitting unit, and the other electrode 115 of the LED module 113 is connected to the right terminal of the current limiting circuit 110 and the LED. Still another electrode 116 of the module 113 is connected to the left terminal of the current limiting circuit 110 and the current feedback terminal 106 of the constant current driver 101. The electrode 114 is connected to the anode of the first LED array 108 (see FIG. 1) and the second LED array 109 (see FIG. 1), and the electrodes 115 and 116 are connected to the cathodes of the first LED array 108 and the second LED array 109, respectively. .

  Next, the structure of the LED module 113 will be described with reference to FIG. In FIG. 2, the LED module 113 simulates an actual shape (plan view), and FIG. 3 is a cross-sectional view of the LED module 113. In FIG. 3, the LED module 113 includes electrodes 114, 115, 116 (see FIG. 2) and wiring electrodes (not shown) formed on the upper surface of the module substrate 117, and double and circular dam materials 118, 119. The first fluorescent member 121 is filled in a region inside the dam member 119, and the second fluorescent member 120 is filled in a region outside the dam member 119 and inside the dam member 118. In FIG. 3, the LED 108a (see FIG. 1) included in the first LED array 108 (see FIG. 1) is obtained by covering the LED die 108b with the first fluorescent member 121 and included in the second LED array 109 (see FIG. 1). The LED 109a (see FIG. 1) is obtained by covering the LED die 109b with the second fluorescent member 120. The LED dies 108b and 109b are die-bonded on the module substrate 117 and are electrically connected to wiring electrodes (not shown) by wires 122.

  The module substrate 117 is made of a plate material having high surface reflectivity and good thermal conductivity, such as ceramics or a metal substrate whose surface is insulated. The LED dies 108b and 109b are both blue light emitting diodes. The first fluorescent member 121 contains a phosphor that emits green to yellow light and a phosphor that emits red light in a silicone resin. When the LED die 108b emits light, the LED 108a emits reddish light (2700K). The second fluorescent member 120 contains a phosphor that emits yellow light in a silicone resin. When the LED die 109b emits light, the LED 109a emits white light (5400K) having a high color temperature.

  In the LED module 113 of the LED lighting device 100, a plurality of LEDs 108 a (first LEDs) and LEDs 109 a (second LEDs) are mounted on one module substrate 117. However, the LED lighting device of the present invention is not limited to this structure, and the first LED and the second LED may be mounted on separate substrates. If the first and second LEDs are mounted on one substrate as in the LED lighting device 100, handling is facilitated, and additional optical members such as lenses can be miniaturized.

  Further, in the LED lighting device 100, the LED 108a (first LED) has the upper surface of the LED die 108b covered with the first fluorescent member 121, and the LED 109a (second LED) has the upper surface of the LED die 109b covered with the second fluorescent member 120. It was a thing. Further, the first fluorescent member 121 is connected between the LEDs 108a, the second fluorescent member 120 is connected between the LEDs 109a, and the LEDs 109a are arranged outside the region where the LEDs 108a are arranged. However, in the LED lighting device of the present invention, each LED is not limited to such a shape and arrangement, and may be a discrete component, for example, one by one. Further, the LED may not include a fluorescent member. For example, an LED die that emits red light as the first LED may be used without the fluorescent member. In addition, by adopting a small discrete LED such as a surface mount type, the first and second LEDs can be arranged in a desired arrangement to improve color mixing in the high-illuminance emission mode. On the other hand, if the first and second LEDs are configured as in the LED lighting device 100, miniaturization and density increase are promoted, so that it is effective for additional optical members such as handling and lenses as described above. .

Further, in the LED lighting device 100, the color temperature of the emission color of the LED 108a (first LED) is lower than the color temperature of the emission color of the LED 109a (second LED), the first LED column 108 includes only the LED 108a, and the second LED column 109 includes Only the LED 109a was included. However, in the LED lighting device of the present invention, the second LED may be partially included in the first LED row, and conversely, the first LED may be included in the second LED row. At this time, if the ratio of the first LEDs included in the first LED array is larger than the ratio of the first LEDs included in the second LED array, the low-illuminance emission mode in which only the first LED array is lit, the first and second LED arrays emit light simultaneously. The color temperature is lower than in the high light emission mode, making it easier to use for night lights and guide lights. In addition, when using low illumination light emission mode for uses other than a nightlight, the color temperature of high illumination light emission mode may become lower than low illumination light emission mode.

(Second Embodiment)
The LED lighting device 100 shown in FIGS. 1 to 3 is a constant current driver 101 whose power supply circuit can change the output current, and the first LED array 108 and the second LED array 109 are connected to the constant current driver 101 (power supply circuit). The current limiting circuit 110 was connected in series to the first LED row 108 in parallel. The constant current driver 101 sets a current value to be output based on a control signal 102a sent from a remote controller or a sensor. The constant current driver 101 adjusts the voltage applied to the first and second LED arrays 108 and 109 which are loads in order to output the set current. That is, the LED illumination device 100 indirectly controls the load with the voltage through monitoring the output current, and switches between the low illuminance light emission mode and the high illuminance light emission mode. On the other hand, the output voltage of the power supply circuit may be set directly to control the first LED array and the second LED array that are loads. Therefore, an LED lighting device 200 including a variable voltage source 201 that can directly change an output voltage as a power supply circuit will be described as a second embodiment with reference to FIGS. 4 to 6.

  First, the circuit configuration of the LED lighting device 200 will be described with reference to FIG. FIG. 4 is a circuit diagram of the LED lighting device 200. In FIG. 4, the variable voltage source 201 (power supply circuit) included in the LED lighting device 200 has a control signal input terminal 202 to which a control signal 202a for setting a voltage value to be output is input and a power input to which a power line 203a is connected. There are a terminal 203, a ground terminal 204 that is the ground level 204a of the control signal 202a and the power line 203a, an output terminal 205 that applies a voltage to the load, and a current feedback terminal 206 from which a current returns from the load.

  A plurality of LEDs 207a (first LEDs) are connected in series to form a first LED row 207. Similarly, a plurality of LEDs 208a (second LEDs) constitute a third LED row 208, and a plurality of LEDs 209a (second LEDs) constitute a fourth LED row 209. Configure. The first, third, and fourth LED strings 207, 208, and 209 are connected in series, and the anode of the first LED string 207 is connected to the output terminal 205 of the variable voltage source 201. Note that the third LED array 208 and the fourth LED array 209 constitute a second LED array that emits light together with the first LED array 207 in the high illumination emission mode. A bypass circuit 210 including a depletion type FET 210a (hereinafter referred to as a depletion type FET) and a resistor 210b is connected to a connection portion between the first LED row 207 and the third LED row 208. Similarly, a bypass circuit 211 including an FET 211a and a resistor 211b is connected to a connection portion between the third LED array 208 and the fourth LED array 209, and a current limiting circuit 212 including an FET 212a and a resistor 212b is connected to the cathode of the fourth LED array 209. doing. The resistors 210b, 211b, and 212b are current detection resistors.

Next, the light emission block included in the LED lighting device 200 shown in FIG. 4 will be described. In the LED lighting device 200, the light emission block is a circuit including the first, third, and fourth LED rows 207, 208, and 209, the bypass circuits 210 and 211, and the current limiting circuit 212. The LED 207a emits light at a color temperature (first emission color) of 2700K, and the LED 208a and the LED 209a emit light at a color temperature (second emission color) of 5400K. That is, only the first LED row 207 is lit in the low-illuminance light emission mode like a night light, and the emission color becomes the reddish first emission color. On the other hand, in the high illuminance light emission mode as in normal illumination, both the first LED row 207 and the third and fourth LED rows 208 and 209 emit light, and the emission color is bluish white. The emission color in the high illuminance emission mode is lower than 5400K because the emission of the first LED row 207 and the emission of the third and fourth LED rows 208 and 209 (second LED row) are mixed.

  Here, the number of LEDs 207a is smaller than the number of LEDs 208a and 209a. Therefore, the threshold value Vth1 of the first LED array 207 configured by connecting LEDs 207a in series is smaller than the threshold values Vth3 and VTh4 of the third and fourth LED arrays 208 and 209 configured by connecting LEDs 208a and 209a in series. . The threshold value of the first LED string 207 is the product of the forward voltage drop of the LED 207a and the number of series stages thereof. Similarly, the threshold values Vth3 and Vth4 of the third and fourth LED strings 208 and 209 are the order of the LEDs 208a and 209a, respectively. It is the product of the directional voltage drop and the number of series stages.

  The FETs 210a, 211a, and 212a included in the bypass circuit 210 and the like have a current Ids flowing between the source and the drain if the gate-drain voltage Vgs is higher than the FET-specific threshold, while the current detection resistors 210b, 211b, and 212b. Get negative feedback from As a result, when the output voltage V of the variable voltage source 201 is sufficiently higher than the threshold value Vth1 of the first LED string 207, the bypass circuit 210 is lower than the sum of the threshold value Vth1 of the first LED string 207 and the threshold value Vth2 of the third LED string 208. Constant current operation. At this time, current flows only in the first LED row 207, and only the first LED row 207 is lit. This state is the low illumination light emission mode. Note that when the output voltage V of the variable voltage source 201 is sufficiently higher than the sum of the threshold value Vth1 of the first LED string 207 and the threshold value Vth3 of the third LED string 208, and the current also flows through the third LED string 208, it is included in the bypass circuit 210. FET 210a to be cut off.

  Similarly, the output voltage V of the variable voltage source 201 is sufficiently higher than the sum of the threshold value Vth1 of the first LED string 207 and the threshold value Vth3 of the third LED string 208, and the threshold value Vth1 of the first LED string 207 and the threshold value Vth3 of the third LED string 208 are When lower than the sum of the threshold values Vth4 of the fourth LED array 209, the bypass circuit 211 operates at a constant current. At this time, a current flows through the first LED row 207 and the third LED row 208, and the first LED row 207 and the third LED row 208 are lit. This state is a light emission mode with an intermediate illuminance. Note that the output voltage V of the variable voltage source 201 is sufficiently higher than the sum of the threshold value Vth1 of the first LED string 207, the threshold value Vth3 of the third LED string 208, and the threshold value Vth4 of the fourth LED string 209, so that the current also flows through the fourth LED string 209. Then, the bypass circuit 211 is cut off.

  When the output voltage V of the variable voltage source 201 becomes sufficiently higher than the sum of the threshold value Vth1 of the first LED string 207, the threshold value Vth3 of the third LED string 208, and the threshold value Vth4 of the fourth LED string 209, the current limiting circuit 212 operates at a constant current. . At this time, a current flows through the first LED string 207, the third LED string 208, and the fourth LED string 209, and the first LED string 207, the third LED string 208, and the fourth LED string 209 are turned on. This state is a high illumination light emission mode. The second LED array that emits light in the high-illuminance light emission mode includes a third LED array 208 and a fourth LED array 209.

As described above, the LED device 200 switches between the low illuminance light emission mode, the intermediate illuminance light emission mode, and the high illuminance light emission mode according to the output voltage V of the variable voltage source 201. The LED lighting device 200 performs dimming in three stages. When finer dimming is performed, the number of partial LED strings connected in series may be increased to finely control the output voltage of the variable voltage source. In the LED lighting device 200, the current detection resistors 201b, 211b, and 212b are provided in a distributed manner for each of the bypass circuits 210 and 211 and the current limiting circuit 212. However, the current detection resistors may be combined in one place. In this case, an operation equivalent to that of the LED lighting device 200 can be realized by applying the divided voltage of the current detection resistor to the gate of the FET included in the bypass circuit or the like. FET
210a, 211a, 212a may be replaced with other elements such as enhancement type FETs. In this case, it is necessary to add a circuit for performing feedback and cutoff.

  Next, referring to FIG. 5, the light emitting unit of the LED lighting device 200 shown in FIG. 4 will be described. FIG. 5 is a circuit diagram showing the light emitting unit of the LED lighting device 200 as a block. Here, the light emitting unit is a circuit including first, third, and fourth LED rows 207, 208, and 209, bypass circuits 210 and 211, and a current limiting circuit 212 in FIG. In FIG. 5, the output terminal 205 of the variable voltage source 201 is connected to the electrode 215 of the LED module 214 which is a light emitting unit, and the other electrode 216 of the LED module 214 is connected to the current feedback terminal 206 of the variable voltage source 201. ing. The electrode 215 is connected to the anode of the first LED row 207 (see FIG. 4), and the electrode 216 is connected to the current detection resistor 210b (see FIG. 4) of the bypass circuit 211 (see FIG. 4).

  Next, the structure of the LED module 214 will be described with reference to FIG. In FIG. 5, the LED module 214 simulates an actual shape (plan view), and FIG. 6 is a cross-sectional view of the LED module 214. In FIG. 6, the LED module 214 has a rectangular dam member 218 and a double circular dam member 219, 220 in addition to electrodes 215, 216 (see FIG. 2) and wiring electrodes (not shown) on the upper surface of the module substrate 217. The first fluorescent member 223 is filled in the region inside the dam material 220, the second fluorescent member 222 is filled in the region outside the dam material 220 and inside the dam material 219, and the dam material 219 A light-shielding covering member 221 is filled in an area outside the dam material 218. In FIG. 6, the LED 207a included in the first LED row 207 (see FIG. 4) is obtained by covering the LED die 207b with the first fluorescent member 223, and the third and fourth LED rows 208 and 209 (see FIG. 4). The LEDs 208a and 209a included in the LED are obtained by coating the LED dies 208b and 209b with the second fluorescent member 222. Further, parts such as the FETs 210 a and 212 a included in the bypass circuits 210 and 211 and the current limiting circuit 212 are covered with a covering member 221. Components such as the LED dies 207b, 208b, and 209b and the FETs 210a and 212a are die-bonded on the module substrate 217 and electrically connected to wiring electrodes (not shown) by wires 224.

  The module substrate 217 uses a plate material having high surface reflectivity and good thermal conductivity, such as ceramics or a metal substrate whose surface is insulated. The LED dies 207b, 208b, and 209b are all blue light emitting diodes. The first fluorescent member 223 includes a phosphor that emits green to yellow light and a phosphor that emits red light in a silicone resin. When the LED die 208b emits light, the LED 208a emits reddish light (2700K). The second fluorescent member 222 contains a phosphor that emits yellow light in a silicone resin. When the LED dies 208b and 209b emit light, the LEDs 208a and 209a emit light in white (5400K) having a high color temperature.

100, 200 ... LED lighting device,
101 ... Constant current driver (power supply circuit),
102, 202 ... control signal input terminals,
102a, 202a ... control signals,
103, 203 ... power input terminal,
103a, 203a ... power lines,
104, 204 ... ground terminals,
104a, 204a ... ground level,
105, 205 ... output terminals,
106, 206 ... current feedback terminals,
108,207 ... 1st LED row,
108a, 207a ... LED (first LED),
108b, 109b, 207b, 208b, 209b ... LED die,
109 ... 2nd LED row,
109a, 208a, 209a ... LED (second LED),
110, 212 ... current limiting circuit,
111, 210a, 211a, 212a ... depletion type FET,
112, 210b, 211b, 212b ... resistance,
113, 214 ... LED module (light emitting part),
114, 115, 116, 215, 216 ... electrodes,
117, 217 ... module substrate,
118,119,218,219,220 ... dam material,
120, 222 ... second fluorescent member,
121, 223 ... first fluorescent member,
122, 224 ... wire,
208 ... Third LED row,
209 ... 4th LED row,
210, 211 ... bypass circuit,
221: Cover member.

Claims (3)

In LED lighting devices with different emission colors when emitting light with low illuminance and when emitting light with high illuminance,
A first LED row and a second LED row in which a plurality of LEDs are connected in series;
A power supply circuit having one output terminal for applying a voltage to the first LED row and the second LED row,
The plurality of LEDs include at least a first LED that emits light in a first emission color and a second LED that emits light in a second emission color,
The first LED row is different in emission color from the second LED row,
When the voltage output from the power supply circuit is low, only the first LED row is lit,
The number of LEDs included in the first LED row is less than the number of LEDs included in the second LED row,
A current limiting circuit is connected in series to the first LED row,
The plurality of LEDs are mounted on one module substrate,
The LED die included in the first LED has an upper surface covered with a first fluorescent member,
The LED die included in the second LED has an upper surface covered with a second fluorescent member,
The first fluorescent member is connected between the first LEDs, the second fluorescent member is connected between the second LEDs ,
The power supply circuit is a variable voltage source capable of changing an output voltage,
The first LED row and the second LED row are connected in series to the power supply circuit,
A bypass circuit is provided at a connection portion between the first LED row and the second LED row,
The LED lighting device according to claim 1, wherein the bypass circuit is cut off in accordance with a current flowing through the second LED array . Wherein said 1LED is arranged at the center of the module substrate, enclose the first 2LED takes the first 1LED,
The first LED is surrounded by a circular first dam material,
The second LED and the first dam material are surrounded by a circular second dam material,
The LED lighting according to claim 1, wherein the bypass circuit is disposed on the module substrate and is surrounded by a rectangular third dam material and a part of the second dam material. apparatus. The color temperature of the emission color of the first LED is lower than the color temperature of the emission color of the second LED, and the proportion of the first LED included in the first LED row is greater than the proportion of the first LED included in the second LED row. The LED illumination device according to claim 1 or 2, characterized in that

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