JP2011165400A - Power supply circuit and lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply circuit of simple structure which can control dimming and emission color of a light emitting element, and to provide a lighting system. <P>SOLUTION: The power supply circuit includes: a direct current power generating means for generating direct current power to supply the power to a plurality of semiconductor light emitting elements; an external signal receiving means 160 for receiving an external signal having a variable frequency and a variable duty ratio; a control means 170 for generating a control signal for controlling the current, which flows in the semiconductor light emitting elements, based on the external signal received by the external signal receiving means; and a plurality of current control means for separately controlling the current, which flows in each of the semiconductor light emitting elements, based on the control signal generated by the control means. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a power supply circuit for lighting a semiconductor light emitting element such as an LED (light emitting diode), and an illumination device.

  In recent years, LED lighting devices including LED elements as semiconductor light emitting elements have been put into practical use. The LED lighting device includes a power supply circuit and a semiconductor light emitting element. The power supply circuit boosts and lowers the supplied power. Thus, the power supply circuit controls the current flowing through the semiconductor light emitting element. The semiconductor light emitting device emits light when current is supplied.

  For example, Patent Document 1 discloses a technique for adjusting the brightness of light from a light emitting element by controlling a current flowing through the light emitting element based on an on / off duty ratio of a dimming signal input from the outside. ing.

JP 2007-234415 A

  When LEDs of a plurality of colors are used in the lighting device, the lighting device emits illumination light in which light of a plurality of colors is mixed. With the widespread use of lighting devices using LED elements, a configuration that can adjust the color of illumination light is desired. When changing the color of the illumination light, it is necessary to adjust the light emission amount of each LED element by controlling the currents flowing through the plurality of LED elements having different emission colors.

  However, since the lighting apparatus described in Patent Document 1 described above is only a signal instructing light brightness and darkness, the current flowing through a plurality of light emitting elements is individually controlled to perform color adjustment. It can't be done.

  In view of the above, an object of the present invention is to provide a power supply circuit and a lighting device that can control light control and light emission color of a light emitting element with a simple configuration.

  The power supply circuit according to claim 1 generates DC power and supplies DC power to a plurality of semiconductor light emitting elements; and external signal receiving means that receives an external signal whose frequency and duty ratio are variable; Control means for generating a control signal for controlling the current flowing in the semiconductor light emitting element based on the external signal received by the external signal receiving section; and each of the semiconductors based on the control signal generated by the control means A plurality of current control means for individually controlling currents flowing through the light emitting elements.

  In the present invention and each of the following inventions, each configuration is as follows unless otherwise specified.

  The semiconductor light emitting element is, for example, a light emitting diode or an organic EL element. The plurality of semiconductor light emitting elements are provided with at least two kinds of semiconductor light emitting elements that emit light of different wavelengths. The number of each semiconductor light emitting element is appropriately used according to a desired light amount and color.

  According to the present invention, the power supply circuit can individually control the light emission amount of each semiconductor light emitting element according to the input external signal. That is, the power supply circuit determines the light emission amount and the light emission color of the semiconductor light emitting element according to the external signal. Thereby, the power supply circuit can control the total amount of light emission and the light emission color. As a result, the power supply circuit can control the light emission color without changing the light emission amount. The power supply circuit can control the light emission amount without changing the light emission color.

  A power supply circuit according to a second aspect is the power supply circuit according to the first aspect, wherein the control means is a dimming table for determining a total light emission amount of the semiconductor light emitting element; A toning table for determining a ratio; and the dimming table includes information indicating either the duty ratio of the external signal or the frequency of the external signal and the total amount of light emission of the semiconductor light emitting element. And the toning table indicates the ratio of the duty ratio of the external signal or the frequency of the external signal that is not used for the association of the dimming table and the light emission amount of each of the semiconductor light emitting elements. Information is stored in association with each other, and the control means determines a total light emission amount of the semiconductor light emitting element based on the external signal and the dimming table, and determines the frequency of the external signal and the toning table. Based on the bets, determining the ratio of the light emission amount of each of the semiconductor light emitting element, characterized in that.

  The total amount of light emitted from the semiconductor light emitting elements is the sum of the luminous fluxes emitted from each semiconductor light emitting element. The ratio of the light emission amount is the ratio of the light emission amounts of the semiconductor light emitting elements that emit light having different wavelengths, and corresponds to the color of the combined light of the light from the semiconductor light emitting elements.

  The information stored in the toning table may be any information that can be recognized by the current control means.

  According to the present invention, the power supply circuit determines the light emission amount of the semiconductor light emitting element by referring to the dimming table according to either the duty ratio or the frequency of the input external signal, The light emission color of the semiconductor light-emitting element is determined by referring to the toning table according to the duty ratio or frequency of the external signal not used for the correspondence, and the control signal is generated according to the determined light emission amount and light emission color. To do. Thereby, the power supply circuit can control the light emission amount and the light emission color of the synthesized light of the semiconductor light emitting element based on one external signal.

  Further, as one means for realizing the present invention, for example, the current control means includes a switch for controlling ON / OFF of a current flowing through the semiconductor light emitting element, and receives a control signal received from the control means. On the basis of this, it is conceivable to realize this by controlling ON / OFF of the switch and controlling the effective value of the current flowing through the semiconductor light emitting element. Thus, the power supply circuit controls the light emission amount of each semiconductor light emitting element by individually controlling ON / OFF of the current flowing through each semiconductor light emitting element in accordance with the input external signal. As a result, the power supply circuit can control the emission amount and emission color of the combined light of the semiconductor light emitting element based on one external signal.

  The current control unit includes a capacitor connected in parallel with the semiconductor light emitting element, and a switch connected between the capacitor and the DC power generation unit, and receives control from the control unit. It may be realized by controlling ON / OFF of the switch based on a signal, controlling a voltage generated between both terminals of the capacitor, and controlling a current value of a current flowing through the semiconductor light emitting element. As a result, the power supply circuit individually controls the current value of the current flowing through each semiconductor light emitting element by controlling the charge of the capacitor connected in parallel with each semiconductor light emitting element in accordance with the input external signal. The light emission amount of each semiconductor light emitting element is controlled. As a result, the power supply circuit can control the emission amount and emission color of the combined light of the semiconductor light emitting element based on one external signal.

  According to a third aspect of the present invention, there is provided a lighting device comprising: a plurality of semiconductor light emitting elements; a power supply circuit according to the first or second aspect; and a fixture body provided with the power supply circuit.

  According to the present invention, the lighting device can individually control the light emission amount of each semiconductor light emitting element in accordance with an input external signal. Thereby, the illuminating device which can control the total amount of emitted light amount and emitted light color can be provided.

  According to the first aspect of the present invention, the power supply circuit can individually control the light emission amount of each semiconductor light emitting element according to the input external signal. Thereby, the power supply circuit can control the total amount of light emission and the light emission color.

  According to the invention of claim 2, the power supply circuit determines the light emission amount of the semiconductor light emitting element by referring to the light adjustment table according to either the duty ratio or the frequency of the input external signal. The light emission color of the semiconductor light emitting element is determined by referring to the toning table according to the duty ratio or frequency of the external signal that is not used for the correspondence of the light table, and controlled according to the determined light emission amount and light emission color. Generate a signal. Thereby, the power supply circuit can control the light emission amount and the light emission color of the synthesized light of the semiconductor light emitting element based on one external signal.

  According to invention of Claim 3, the illuminating device can control the light-emission quantity of each semiconductor light-emitting element individually according to the external signal input. Thereby, the illuminating device which can control the total amount of emitted light amount and emitted light color can be provided.

FIG. 1 is an explanatory diagram for explaining a configuration example of a lighting apparatus according to an embodiment of the present invention. FIG. 2 is an explanatory diagram for describing an example of a dimming table stored in the illumination device illustrated in FIG. 1. FIG. 3 is an explanatory diagram for explaining the relationship between the duty ratio and the brightness in the lighting apparatus shown in FIG. 1. FIG. 4 is an explanatory diagram for describing an example of a toning table stored in the lighting device illustrated in FIG. 1. FIG. 5 is an explanatory diagram for explaining the relationship between the frequency and the color in the lighting apparatus shown in FIG. 1. FIG. 6 is an explanatory diagram for describing another configuration example of the lighting circuit of the lighting device illustrated in FIG. 1. FIG. 7 is an explanatory diagram for explaining still another configuration example of the lighting circuit of the lighting device illustrated in FIG. 1.

  Hereinafter, a power supply circuit and an illumination device according to an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an explanatory diagram for explaining a configuration example of a lighting apparatus according to an embodiment of the present invention.
The illumination device 100 includes a red LED 200, a green LED 300, and a blue LED 400. The illuminating device 100 implement | achieves various light emission colors by controlling the light emission amount of each LED.

  The lighting device 100 includes a power system 110, a noise filter 111, a rectifier circuit 112, a power factor correction circuit 120, and a first control circuit 121. In addition, the lighting device 100 operates the lighting circuit 130 that controls the light emission of the red LED 200, the second control circuit 131 that controls the operation of the lighting circuit 130, the lighting circuit 180 that controls the light emission of the green LED 300, and the operation of the lighting circuit 180. A second control circuit 181 for controlling, a lighting circuit 190 for controlling light emission of the blue LED 400, and a second control circuit 191 for controlling the operation of the lighting circuit 190 are provided. Furthermore, the lighting device 100 includes a controller 160 and a third control circuit 170.

  Since the lighting circuit 180 and the lighting circuit 190 have the same configuration as the lighting circuit 130, detailed description thereof is omitted.

  The power system 110 is an AC power source. The power system 110 may be a connection terminal connected to an AC power source.

  The noise filter 111 includes a capacitor C1, a reactor L1, and a capacitor C2. The capacitor C1 and the capacitor C2 are connected in parallel with the power system 110. Reactor L2 is connected between capacitors C1 and C1. The noise filter 111 prevents noise generated by the lighting device 100 from leaking to the power system 110.

  The rectifier circuit 112 includes a rectifier bridge including diodes D1, D2, D3, and D4. The rectifier circuit 112 rectifies AC power supplied from the power system 110 into DC power.

  The power factor correction circuit 120 includes a reactor L2, a transistor Tr1, a diode D5, and capacitors C3 and C4. The transistor Tr1 and the capacitor C4 are connected in parallel with the capacitor C3. Reactor L2 is connected between transistor Tr1 and capacitor C3. The diode D5 is connected between the transistor Tr1 and the capacitor C4. The power factor correction circuit 120 functions as a boosting unit.

  The first control circuit 121 controls ON / OFF of the transistor Tr1 based on a preset timing. Thereby, the power factor correction circuit 120 controls the voltage generated across the capacitor C4. That is, the power factor correction circuit 120 boosts and outputs the voltage generated across the capacitor C3.

  The lighting circuit 130 includes a step-down circuit 140 and a constant current circuit 150.

  The step-down circuit 140 includes a transistor Tr2, a diode D6, a reactor L3, and a capacitor C5. The diode D6 and the capacitor C5 are connected in parallel with the capacitor C4. The transistor Tr2 is connected between the capacitor C4 and the diode D6. Reactor L3 is connected between diode D6 and capacitor C5. The step-down circuit 140 functions as a step-down unit.

  The second control circuit 131 controls ON / OFF of the transistor Tr2 based on the control of the third control circuit 170. Thereby, the step-down circuit 140 controls the voltage generated at both ends of the capacitor C5, and controls the maximum value of the current flowing through the LED 200.

  The constant current circuit 150 includes voltage sources E1 and E2, resistors R1, R2, and R3, diodes D7 and D8, transistors Tr3 and Tr4, and an operational amplifier 151. The transistor Tr3 is connected in series with the LED 200. The resistor R3 is connected to the emitter of the transistor Tr3.

  A transistor Tr4 is connected between the base of the transistor Tr3 and GND. A diode D8, an operational amplifier 151, and a voltage source E2 are connected between the base of the transistor Tr3 and GND. Further, a resistor R2 and a voltage source E1 are connected between the base of the transistor Tr3 and GND. Furthermore, a resistor R1 and a diode D7 are connected between the collector of the transistor Tr3 and the voltage source E1. The constant current circuit 150 controls the current value of the current flowing through the LED 200.

  For example, when the voltage between the base and the emitter of the transistor Tr3 exceeds a predetermined value, the transistor Tr3 turns on the current path. Further, when the voltage between the base and the emitter of the transistor Tr3 becomes less than a predetermined value, the transistor Tr3 turns off the current path. That is, since ON / OFF of the transistor Tr3 is switched according to the current value of the current flowing through the LED 200, the constant current circuit 150 can keep the current value of the current flowing through the LED 200 constant.

  Further, the second control circuit 131 controls ON / OFF of the transistor Tr4 based on the control of the third control circuit 170. Thereby, the second control circuit 131 controls ON / OFF of the transistor Tr3. The constant current circuit 150 controls the effective value of the current flowing through the LED 200 by controlling ON / OFF of the transistor Tr3 based on the control of the third control circuit 170. As a result, the constant current circuit 150 can control the light emission amount of the LED 200.

  The controller 160 is an input terminal to which an external signal is input from an external controller. It may be a receiving device that receives infrared rays or radio waves transmitted from a remote control or the like.

  The third control circuit 170 determines the frequency and duty ratio of the external signal input from the controller 160. The third control circuit 170 includes a memory 171 that stores a dimming table that associates the duty ratio of the external signal with the brightness of the entire lighting device 100.

  2 and 3 are explanatory diagrams showing examples of the dimming table. The dimming table stores the total amount of luminous flux emitted from the LED 200, the LED 300, and the LED 400 in association with the duty ratio of the external signal.

  The third control circuit 170 determines the duty ratio of the external signal input from the controller 160, and reads information indicating brightness corresponding to the determined duty ratio from the dimming table. The third control circuit 170 transmits a control signal to the second control circuits 131, 181 and 191 so as to control the light emission amount of the entire lighting device 100 based on the information read from the dimming table. Accordingly, the third control circuit 170 controls the total light emission amount of the LED 200, the LED 300, and the LED 400.

  Further, the third control circuit 170 includes a memory 172 that stores a toning table in which the frequency of the external signal and the color of the illumination light of the illumination device 100 are associated with each other.

  4 and 5 are explanatory diagrams showing examples of the toning table. The toning table stores the light emission amount of the LED 200, the light emission amount of the LED 300, the light emission amount of the LED 400, and the frequency of the external signal in association with each other.

  The third control circuit 170 determines the frequency of the external signal input from the controller 160, and reads information corresponding to the determined frequency from the toning table. The third control circuit 170 transmits a control signal for controlling the light emission amount of each light emitting element of the lighting device 100 to the second control circuits 131, 181, and 191 based on the information read from the toning table. To do. Thereby, the 3rd control circuit 170 controls the light emission amount of LED200, LED300, and LED400 separately.

  That is, the third control circuit 170 refers to the dimming table based on the duty ratio of the external signal, and determines the total light emission amount of the LED 200, LED 300, and LED 400. Furthermore, the third control circuit 170 refers to the toning table based on the frequency of the external signal, and determines the ratio of the light emission amounts of the LED 200, LED 300, and LED 400 within the determined light emission amount. The third control circuit 170 generates control signals to be transmitted to the second control circuits 131, 181, and 191 based on the determined light emission amount and ratio, respectively.

  The second control circuits 131, 181, and 191 control ON / OFF of the transistor Tr4 based on the control signal transmitted from the third control circuit 170. Thereby, the second control circuits 131, 181, and 191 individually control the effective values of the currents flowing through the LED 200, the LED 300, and the LED 400.

  For example, the second control circuits 131, 181, and 191 generate a PWM signal for controlling ON / OFF of the transistor Tr4 based on the received control signal. In this case, the second control circuits 131, 181, and 191 set the duty ratio of the PWM signal based on the received control signal. The second control circuits 131, 181, and 191 control the ON / OFF of the transistor Tr4 by inputting the generated PWM signal to the base of the transistor Tr4.

  That is, the second control circuit 131 controls the light emission amount of the LED 200 based on the control signal transmitted from the third control circuit 170. The second control circuit 181 controls the light emission amount of the LED 300 based on the control signal transmitted from the third control circuit 170. The second control circuit 191 controls the light emission amount of the LED 400 based on the control signal transmitted from the third control circuit 170.

  Thereby, the illuminating device 100 controls the mixed color (color of illumination light) and the amount of light emitted from the LED 200, the LED 300, and the LED 400 based on the external signals input to the pair of control signal terminals. I can do it. As a result, it is possible to provide a power supply circuit and a lighting device that can control the emission color of the light emitting element with a simple configuration. Note that the color of the illumination light described above is, for example, the color temperature, chromaticity, or hue of the mixed color.

  Further, the LED 200 is a red LED, the LED 300 is a green LED, and the LED 400 is a blue LED. However, each light emitting element may emit light of any wavelength. In addition, the present invention can be implemented by any number of light emitting elements included in the lighting device 100 as long as the number is at least two.

  For example, the light emitting element included in the lighting device 100 may be configured by a white LED including a blue LED and a yellow phosphor, and a red LED. In this case, the red LED can supplement the light emitted from the white LED with less red band light. As a result, the color rendering properties (Ra value) of the lighting device 100 can be improved. Further, by controlling the ratio of the light emission amount of the red LED and the light emission amount of the white LED, the light emission color of the lighting device 100 is controlled in the range between the neutral white color and the light bulb color (for example, color temperature = 3000K to 5000K). I can do it.

  Further, the LEDs 200, 300, and 400 may be configured to be removable from the power supply circuit of the lighting device 100. In this case, the illumination device 100 includes a terminal to which an LED or another light emitting element can be attached.

  In the above-described embodiment, the dimming table stores the duty ratio of the external signal and the light emission amount in association with each other, and the toning table stores the frequency of the external signal and the light emission color in association with each other. However, it is not limited to this configuration. For example, the dimming table may store the frequency of the external signal and the light emission amount in association with each other, and the toning table may store the duty ratio of the external signal in association with the light emission color. In this case, the third control circuit 170 determines the light emission amount based on the frequency of the external signal, and determines the light emission color (ratio of the light emission amount of each light emitting element) based on the duty ratio of the external signal.

  The light emission amount stored in advance in the dimming table is a value corresponding to the maximum output value of the light emission amount of the single color LED. By configuring the dimming table in this way, the lighting device 100 can keep the light emission amount constant regardless of the color of the light emission.

  In addition, the ratio of the light emission amount of each light emitting element is stored in advance in the toning table, but the present invention is not limited to this configuration. The information stored in the toning table may be any information as long as it can be recognized by the second control circuits 131, 181, and 191. For example, the configuration may be such that the duty ratio of the PWM signal for controlling the transistor Tr4 is stored in advance in the toning table.

  Further, in the above-described embodiment, the lighting circuit 130 has been described as a configuration in which the constant current circuit 150 controls the effective value of the current flowing through the LED 200, but is not limited to this configuration. The lighting circuit 130 may be configured to control the effective value of the current flowing through the LED 200 by the step-down circuit 140.

  FIG. 6 is an explanatory diagram for explaining another example of the lighting circuit 130. Since the lighting circuits 180 and 190 have the same configuration as the lighting circuit 130, detailed description thereof is omitted.

  The second control circuit 131 controls ON / OFF of the transistor Tr2 based on the control of the third control circuit 170. Thereby, the step-down circuit 140 controls the voltage generated across the resistor R3. The second control circuit 131 detects the current value of the current flowing through the resistor R3. As a result, the step-down circuit 140 can control the value of the current flowing through the LED 200. That is, the second control circuit 131 controls the voltage generated at both ends of the resistor R3 by controlling the duty ratio of the PWM signal that controls ON / OFF of the transistor Tr2 based on the light emission amount of the LED 200.

  The lighting circuit 130 may be configured to control the effective value of the current flowing through the LED 200 by replacing the constant voltage source of the constant current circuit 150 with a variable voltage source.

  FIG. 7 is an explanatory diagram for explaining another example of the lighting circuit 130. Since the lighting circuits 180 and 190 have the same configuration as the lighting circuit 130, detailed description thereof is omitted.

  The constant current circuit 150 includes resistors R1, R2, and R3, a diode D7, a transistor Tr3, and a variable voltage source E3. The variable voltage source E3 changes the voltage applied between the base terminal and the emitter terminal of the transistor Tr3 based on the control of the second control circuit 131. When the voltage of the variable voltage source E3 changes, the voltage value of the resistor R3 that turns on the transistor Tr3 changes. Thereby, the constant current circuit 150 can control the current value of the current flowing through the LED 200.

  Even if the resistor R3 is replaced with a variable resistor, the effective value of the current flowing through the LED 200 can be controlled in the same manner.

  In addition, this invention is not limited to the said embodiment as it is, It can implement by changing a component in the range which does not deviate from the summary in an implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

  DESCRIPTION OF SYMBOLS 100 ... Illuminating device, 110 ... Electric power system, 112 ... Rectifier circuit, 120 ... Power factor improvement circuit, 121 ... First control circuit, 130 ... Lighting circuit, 131 ... Second control circuit, 140 ... Step-down circuit, 150 ... Constant current circuit, 160 ... controller, 170 ... third control circuit, 171 ... memory, 172 ... memory, 180 ... lighting circuit, 181 ... second control circuit, 190 ... lighting circuit, 191 ... second control circuit 200 ... LED, 300 ... LED, 400 ... LED.

Claims (3)

DC power generating means for generating DC power and supplying power to a plurality of semiconductor light emitting elements;
An external signal receiving means for receiving an external signal having a variable frequency and duty ratio;
Control means for generating a control signal for controlling the current flowing in the semiconductor light emitting element based on the external signal received by the external signal receiving unit;
A plurality of current control means for individually controlling currents flowing through the semiconductor light emitting elements based on a control signal generated by the control means;
A power supply circuit comprising: The control means includes
A dimming table for determining the total amount of light emitted by the semiconductor light emitting device;
A toning table for determining a ratio of light emission amounts of the semiconductor light emitting elements;
Comprising
The dimming table stores either one of the duty ratio of the external signal or the frequency of the external signal in association with information indicating the total amount of light emission of the semiconductor light emitting element,
The toning table stores the duty ratio of the external signal or the frequency of the external signal, which is not used for the association of the dimming table, and information indicating the ratio of the light emission amount of each semiconductor light emitting element in association with each other. ,
The control means includes
Based on the external signal and the dimming table, determine the total amount of light emission of the semiconductor light emitting element,
Based on the frequency of the external signal and the toning table, the ratio of the light emission amount of each of the semiconductor light emitting elements is determined.
The power supply circuit according to claim 1. A plurality of semiconductor light emitting devices;
A power supply circuit according to claim 1 or 2;
An instrument body provided with the power supply circuit;
An illumination device comprising:

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