TW201547327A - Led lighting device - Google Patents

Abstract

The purpose of the present invention is to enable equalizing the change in the optical output of a light source brought about by a first dimmer that performs forward-phase control of an AC voltage and the change in the optical output of a light source brought about by a second dimmer which performs reverse-phase control of an AC voltage. This LED lighting device (10) is provided with a pair of terminals (1, 2), a diode bridge (3), a conversion unit (4), a light source unit (5), a control circuit (6) and a power source unit (7). The control circuit (6) is provided with a determination unit (8) which has a first function for determining whether a dimmer (21) is a first dimmer which performs phase control of the AC voltage or a second dimmer which performs phase control of the AC voltage, and a second function for determining whether the dimmer (21) is in a conducting state or an interrupted state.

Description

LED lighting device

The present invention relates to an LED (Light Emitting Diode) illumination device, and more particularly to an LED illumination device including an LED as a light source portion.

In the past, a lighting fixture has been proposed, and a lighting power source and a lighting power source for supplying electric power to the lighting load have been proposed (Reference 1 [Japanese Laid-Open Patent Publication No. 2013-186944]).

Lighting load, with illumination source such as LED. The lighting power supply is connected to the AC power source via a dimmer. A dimmer that adjusts the conduction period of the phase control of the AC voltage.

The lighting power supply has a rectifier circuit. The rectifier circuit inputs an AC voltage that is phase-controlled by the dimmer. On the input side of the rectifier circuit, a capacitor for reducing high frequency noise is connected.

As a dimmer, in general, a dimmer that performs forward phase control of an alternating current voltage (hereinafter referred to as a first dimmer) and a reverse phase control of an alternating current voltage are known. Dimmer (hereinafter referred to as the second dimmer). In the first dimmer, when the absolute value of the AC voltage is zero, the self-conduction state is turned off. In the second dimmer, when the absolute value of the AC voltage is other than zero, the self-conduction state is turned off.

In the lighting fixture disclosed in Document 1, the capacitor is connected to the input side of the rectifier circuit in the lighting power source. Therefore, when the illuminating device is connected to the second dimmer, when the second dimmer is turned off from the on state, electric charge may be accumulated in the capacitor. Therefore, in the case where the lighting fixture is connected to the second dimmer, the amount of light emitted from the illumination source may increase as compared with the case of connecting to the first dimmer. In other words, in the lighting fixture, it is difficult to change the amount of light emitted from the illumination source generated by the first dimmer to be the same as the change in the amount of light emitted from the illumination source by the second dimmer.

An object of the present invention is to provide an LED illumination device capable of changing a light emission amount of a light source unit generated by a first dimmer that controls an alternating current voltage in phase, and a second dimming control for performing an inverse phase control of an alternating current voltage. The change in the amount of light emitted by the light source portion generated by the device is the same.

An LED lighting device according to the present invention includes: a pair of terminals; a diode bridge that rectifies an AC voltage; and a conversion unit that converts a full-wave rectified voltage of the diode bridge into a predetermined DC voltage Or a given DC current. Further, the LED lighting device of the present invention includes: a light source unit that can be controlled by the predetermined DC voltage converted by the conversion unit or the predetermined DC current; and a control circuit that controls the conversion unit. Further, the LED lighting device of the present invention includes a power supply unit that supplies the first DC voltage to the control circuit by generating a first DC voltage from the voltage of the full-wave rectification of the diode bridge. The light source unit is provided with an LED. One pair of input terminals of the diode bridge are respectively connected to the pair of terminals. A capacitor for removing noise is connected between the pair of input terminals. The diode bridge is connected in parallel with a normally off switching element. The control circuit includes a determination unit having a function of determining that the dimmer is connected to a series circuit of an AC power source and a dimmer that outputs the AC voltage between the pair of terminals. When the absolute value of the AC voltage is zero, the first dimmer that performs the phase control to turn the ON state into the OFF state and the second phase that controls the ON state when the absolute value of the AC voltage is zero is turned off. Which of the dimmers and the second function determine which state the dimmer is in the on state and the off state. The control circuit determines that the dimmer is the second dimmer by the determination unit, and when the determination unit determines that the dimmer is turned off from the on state, the switching element is turned on. .

(Embodiment 1)

Hereinafter, the LED lighting device 10 of the present embodiment will be described with reference to Figs. 1 to 11 .

In addition, hereinafter, control in which the phase control is performed when the absolute value of the AC voltage is zero, and the conduction state is turned off is referred to as forward phase control. Further, when the absolute value of the AC voltage is other than zero, the phase control is performed so that the conduction state is turned off, which is called reverse phase control.

The LED lighting device 10 includes: a pair of terminals 1 and 2; a diode bridge 3 for full-wave rectification of an alternating current voltage; and a converter unit 4 for converting a voltage of full-wave rectification by the diode bridge 3 into a predetermined one. DC voltage. Further, the LED lighting device 10 includes a light source unit 5 that can be turned on by the predetermined DC voltage, a control circuit 6 that controls the converter unit 4, and a power supply unit 7 that supplies electric power to the control circuit 6.

The LED lighting device 10 can electrically connect the AC power supply 20 that outputs the AC voltage to the series circuit of the dimmer 21 that dims the LED illumination device 10, and electrically connects between the pair of terminals 1 and 2. The AC power source 20 is, for example, a commercial power source. In addition, the LED lighting device 10 does not include an AC power source 20 and a dimmer 21. In the following, for convenience of explanation, one of the pair of terminals 1 and 2 is referred to as "first input terminal 1", and the other terminal 2 is referred to as "second input terminal 2".

The diode bridge 3 has four diodes D1 to D4. The first connection point of the cathode of the diode D1 and the anode of the diode D2 is electrically connected to the first input terminal 1. The second connection point of the cathode of the diode D3 and the anode of the diode D4 is electrically connected to the second input terminal 2. The first connection point and the second connection point correspond to one pair of input ends of the diode bridge 3. In short, one of the pair of diode bridges 3 is connected to a pair of terminals 1, 2, respectively.

A capacitor C1 for removing noise is electrically connected between one of the input terminals of the diode bridge 3.

The diode bridge 3 is connected in parallel with the normally-off switching element Q1. Specifically, the switching element Q1 is electrically connected between one of the output terminals of the diode bridge 3.

The switching element Q1 is, for example, a normally-on type n-channel MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The first main terminal (the 汲 terminal in the present embodiment) of the switching element Q1 is electrically connected to one of the pair of output ends of the diode bridge 3. The second main terminal (the source terminal in the present embodiment) of the switching element Q1 is electrically connected to the other one of the pair of output ends of the diode bridge 3. The control terminal (the gate terminal in the present embodiment) of the switching element Q1 is electrically connected to the control circuit 6.

The converter unit 4 is configured to convert the voltage that is full-wave rectified by the diode bridge 3 into the predetermined DC voltage. Further, the converter unit 4 is configured to output the predetermined DC voltage to the light source unit 5. The converter 4 is, for example, a booster circuit. Thereby, the converter unit 4 can turn on the light source unit 5. Further, the LED lighting device 10 uses a booster circuit as the conversion unit 4, but is not limited thereto. The conversion unit 4 may be, for example, a step-down circuit, a step-up and step-down circuit, or the like. Further, the converter unit 4 is configured to convert the voltage that is full-wave rectified by the diode bridge 3 into the predetermined DC voltage, but is not limited to this configuration. For example, the conversion unit 4 may be configured to convert a voltage that is full-wave rectified by the diode bridge 3 into a predetermined direct current. In this case, the converter 4 is, for example, a constant current circuit.

The light source unit 5 includes a plurality of LEDs 9 (refer to FIG. 11). The LED 9, for example, is an LED chip. Further, in the LED lighting device 10, the number of the LEDs 9 may be plural or one.

The control circuit 6 is, for example, a microcomputer on which a program is mounted. The program, for example, is memorized in the memory of the microcomputer set in advance. Further, although the LED lighting device 10 uses a microcomputer as the control circuit 6, it is not limited thereto. The control circuit 6 can be configured, for example, by combining discrete elements.

The power supply unit 7 is configured to generate a first DC voltage from a voltage that is full-wave rectified by the diode bridge 3. Further, the power supply unit 7 is configured to supply the first DC voltage to the control circuit 6. The power supply unit 7 is, for example, a three-terminal regulator. The input terminal of the 3-terminal regulator is electrically connected to the output terminal of the one of the diode bridges 3. The output terminal of the 3-terminal regulator is electrically connected to the control circuit 6. The ground terminal of the 3-terminal regulator is electrically connected to the grounding end of the LED lighting device 10. Thereby, the power supply unit 7 can supply the first DC voltage to the control circuit 6 by generating the first DC voltage from the voltage of the full-wave rectification of the diode bridge 3. Further, the LED lighting device 10 uses a three-terminal regulator as the power supply unit 7, but is not limited thereto. The power supply unit 7 may be, for example, a DC-DC converter.

The control circuit 6 is configured to input a second DC voltage V1 corresponding to a voltage that is full-wave rectified by the diode bridge 3. The LED lighting device 10 is provided with a resistor divider circuit 23. The resistor divider circuit 23 is a series circuit of a resistor R1 and a resistor R2. One end of the resistor R1 is electrically connected to the output end of the one of the diode bridges 3. The other end of the resistor R1 is electrically connected to one end of the resistor R2. In addition, one end of the resistor R2 is electrically connected to the control circuit 6. The other end of the resistor R2 is electrically connected to the ground end of the LED lighting device 10. Thereby, a voltage (voltage across the resistor R2) that divides the voltage that is full-wave rectified by the diode bridge 3 by the resistor divider circuit 23 is input to the control circuit 6. In other words, the control circuit 6 receives the second DC voltage V1 corresponding to the voltage that is full-wave rectified by the diode bridge 3. That is, in the LED lighting device 10, the voltage across the resistor R2 corresponds to the second DC voltage V1.

The control circuit 6 includes a differentiation circuit 13 that differentiates the second DC voltage V1. The differentiation circuit 13 can be constituted, for example, by an operational amplifier, a resistor, and a capacitor.

Further, the control circuit 6 includes a determination unit 8 having a function of determining the first function of the first dimmer that controls the AC voltage in the forward phase and the second phase of the reverse phase control of the AC voltage. Which of the dimmers and the second function determine which state the dimmer 21 is in the on state and the off state. The dimmer 21 is in an on state, and means that the opening and closing portion of the dimmer 21 is set in an ON state in advance. The dimmer 21 is in a disconnected state, and means that the opening and closing portion of the dimmer 21 is in an OFF state. The opening and closing unit is connected in series with the AC power source 20. The opening and closing unit is, for example, a bidirectional thyristor when the dimmer 21 is a first dimmer. Further, in the case where the dimmer 21 is the second dimmer, the opening and closing unit is, for example, a MOSFET or an IGBT (Insulated Gate Bipolar Transistor).

The determination unit 8 includes a first determination unit 11 that determines whether the dimmer 21 is a dimmer of the first dimmer and the second dimmer, and a second determination unit 12 that determines the dimmer 21 Which state is in the on state and the off state.

The first determination unit 11 is configured to determine which of the first dimmer and the second dimmer the dimmer 21 is based on the waveform of the second DC voltage V1.

The first determination unit 11 is configured to determine whether or not the dimmer 21 is the first dimmer based on the degree of matching between the waveform of the second DC voltage V1 and the first reference waveform (see FIG. 3) stored in advance. The first determination unit 11 is configured by, for example, combining an arithmetic circuit provided in advance in the microcomputer with the above program. The first reference waveform is a voltage waveform in a case where the dimmer 21 is the first dimmer. Further, the first reference waveform is stored in the memory. The vertical axis of Figure 3 represents the voltage. The horizontal axis of Figure 3 shows time.

Further, the first determination unit 11 is configured to determine whether or not the dimmer 21 is the second dimmer based on the degree of matching between the waveform of the second DC voltage V1 and the second reference waveform (see FIG. 4) stored in advance. The second reference waveform is a voltage waveform in a case where the dimmer 21 is a second dimmer. Further, the second reference waveform is stored in the memory. The vertical axis of Figure 4 represents the voltage. The horizontal axis of Figure 4 shows time.

In the LED illumination device 10, the first determination unit 11 is configured to determine whether or not the dimmer 21 is the first dimmer based on the degree of matching between the waveform of the second DC voltage V1 and the first reference waveform, but is not limited thereto. this. Further, in the LED illumination device 10, the first determination unit 11 is configured to determine whether or not the dimmer 21 is the second dimmer based on the degree of matching between the waveform of the second DC voltage V1 and the second reference waveform. Not limited to this. The first determining unit 11 may be configured to determine which of the first dimmer and the second dimmer is to be adjusted by the dimmer 21 based on the degree of matching between the waveform of the second DC voltage V1 and the first reference waveform. Light. Alternatively, the first determining unit 11 can determine whether the dimmer 21 is the first dimmer and the second dimmer depending on the degree of matching between the waveform of the second DC voltage V1 and the second reference waveform. Light modulator.

The second determination unit 12 is configured to determine which state of the dimmer 21 is in the on state and the off state based on the second DC voltage V1. The second determining unit 12 is configured to determine the dimmer when the voltage value of the voltage V2 differentiated by the differentiating circuit 13 is greater than or equal to a threshold value Vth (see FIG. 7). The 21 self-conduction state is turned off. The second determination unit 12 is, for example, a determination circuit provided in advance to the microcomputer. T10 in Fig. 7 indicates the time point when the dimmer 21 is turned from the on state. Further, t11 in Fig. 7 indicates a time point at which the voltage value of the voltage V2 becomes a value equal to or lower than the threshold value Vth.

When the first determining unit 11 determines that the dimmer 21 is the second dimmer, and the second determining unit 12 determines that the dimmer 21 is turned off from the on state, the control unit 6 causes the switching element Q1 to be turned off. It is in the ON state. In other words, when the determination unit 8 determines that the dimmer 21 is the second dimmer, and the determination unit 8 determines that the dimmer 21 is turned off from the on state, the control unit 6 causes the switching element to be turned on. Q1 is in the ON state.

In the case of the inventor of the present invention, an LED lighting device (hereinafter referred to as an LED lighting device of a comparative example) having a control circuit different from the control circuit 6 is considered. In the LED lighting device of the comparative example, the same components as those of the LED lighting device 10 are denoted by the same reference numerals, and description thereof will be appropriately omitted. In the following, for the convenience of explanation, the control circuit 6 in the LED illumination device 10 is referred to as "the first control circuit 6", and the control circuit in the LED illumination device of the comparative example is referred to as the "second control circuit". The situation.

Further, the inventors of the present invention considered the case where the first dimmer is connected as the dimmer 21 between the pair of terminals 1 and 2 in the LED illumination device of the comparative example, and the second dimmer is connected as the dimmer. 21 situation.

The second control circuit is configured to maintain the switching element Q1 in an OFF state regardless of whether the dimmer 21 is the first dimmer or the second dimmer, and the dimmer 21 is in an on state or a disconnected state.

In the case of the LED lighting device of the comparative example, the dimmer 21 is the first dimmer, and the voltage waveform of the input voltage V3 in the LED illumination device of the comparative example and the current of the input current I1 in the LED illumination device of the comparative example. The waveform is shown in Figure 5. In Fig. 5, t1 and t3 indicate the time point at which the dimmer 21 is turned on from the cut-off state. In the case of t2 and t4 in Fig. 5, the time point at which the dimmer 21 is turned from the on state is shown.

Further, in the LED lighting device of the comparative example, the dimmer 21 is the second dimmer, and the voltage waveform of the input voltage V3 in the LED illumination device of the comparative example and the input current I1 in the LED illumination device of the comparative example. The current waveform is shown in Figure 6. T5 and t8 in Fig. 6 indicate time points at which the dimmer 21 is turned off from the on state. Reference numerals t6 and t9 in Fig. 6 indicate time points at which the electric charge of the capacitor C1 stored in the LED lighting device of the comparative example is discharged in advance. Reference numeral t7 in Fig. 6 indicates a point in time at which the dimmer 21 is turned on from the cut-off state.

In the LED lighting device of the comparative example, the relationship between the conduction angle generated by the dimmer 21 shown in FIG. 8 and the amount of light emitted from the light source unit 5 is obtained. The vertical axis of Fig. 8 indicates the magnitude of the amount of light emitted from the light source unit 5. The horizontal axis of Fig. 8 indicates the magnitude of the conduction angle generated by the dimmer 21. The curve indicated by the solid line in Fig. 8 shows the case where the dimmer 21 is the second dimmer. The curve indicated by one of the chain lines in Fig. 8 shows the case where the dimmer 21 is the first dimmer.

In the LED illumination device of the comparative example, the amount of light emitted from the light source unit 5 in the case where the dimmer 21 is the second dimmer is as shown in Fig. 8, which is the smallest as compared with the conduction angle generated by the dimmer 21, respectively. The amount of light emitted from the light source unit 5 in the case where the dimmer 21 other than the light amount of the light source unit 5 corresponding to the value and the maximum value is the first dimmer becomes large. In the case of the LED lighting device of the comparative example, when the dimmer 21 is the second dimmer, even if the dimmer 21 is turned off from the on state, electric charge is accumulated in the capacitor C1 of the LED lighting device of the comparative example. possibility. Therefore, in the LED lighting device of the comparative example, the electric charge stored in the capacitor C1 may be supplied to the light source unit 5, and the amount of light emitted from the light source unit 5 may be, for example, higher than that of the light source unit 5 set by the dimmer 21. The possibility of a larger amount of light. Therefore, in the LED illumination device of the comparative example, it is difficult to make the change in the amount of light emitted from the light source unit 5 generated by the first dimmer the same as the amount of light emitted from the light source unit 5 generated by the second dimmer.

In the first control circuit 6 of the LED illumination device 10, when the determination unit 8 determines that the dimmer 21 is the second dimmer, and the determination unit 8 determines that the dimmer 21 is in the off state, the dimming device 21 is turned off. The switching element Q1 is turned on. As a result, in the LED lighting device 10, when the dimmer 21 of the second dimmer is turned off from the on state, the electric charge stored in the capacitor C1 in advance can be discharged. The electric charge accumulated in the capacitor C1 in advance is discharged by the diode D2, the switching element Q1, and the diode D3 when the switching element Q1 is turned from the OFF state.

In the case where the dimmer 21 is the second dimmer in the LED illumination device 10, the voltage waveform of the input voltage V3 in the LED illumination device 10 and the current waveform of the input current I1 in the LED illumination device 10 are shown in FIG. . T12 and t14 in Fig. 9 indicate the time point at which the dimmer 21 is turned off from the on state. T13 in Fig. 9 indicates the time point at which the dimmer 21 is turned on from the cut-off state.

In the LED illumination device 10, the relationship between the conduction angle generated by the dimmer 21 shown in FIG. 10 and the amount of light emitted from the light source unit 5 is obtained. The vertical axis of Fig. 10 indicates the magnitude of the amount of light emitted from the light source unit 5. The horizontal axis of Fig. 10 indicates the magnitude of the conduction angle generated by the dimmer 21. The curve indicated by the solid line in FIG. 10 shows the case where the dimmer 21 is the first dimmer and the case where the dimmer 21 is the second dimmer.

In the LED illumination device 10, the amount of light emitted from the light source unit 5 in the case where the dimmer 21 is the second dimmer is as shown in FIG. 10, and the conduction angle generated by the dimmer 21 is increased, and the dimmer 21 is used. The change in the amount of light emitted from the light source unit 5 in the case of the first dimmer is similarly changed. Thereby, the LED illumination device 10 can change the amount of light emitted from the light source unit 5 in the case where the dimmer 21 is the first dimmer, and the light source unit 5 in the case where the dimmer 21 is the second dimmer. The amount of light emitted is the same. In other words, in the LED illumination device 10, the change in the amount of light emitted from the light source unit 5 by the first dimmer can be made the same as the change in the amount of light emitted from the light source unit 5 by the second dimmer.

The LED lighting device 10, for example, as shown in Fig. 11, is an LED bulb. The LED lighting device 10 includes a module substrate having a pair of terminals 1 and 2, a capacitor C1, a diode bridge 3, a switching element Q1, a resistor divider circuit 23, a converter 4, a control circuit 6, and a power supply unit 7. . Further, the LED lighting device 10 includes a casing 15 that houses a module substrate, a base 16 , a light source unit 5 that is attached to one surface of the casing 15 , and a bulb 17 that diffuses light emitted from the light source unit 5 . In addition, A1 in FIG. 11 shows an area in which the module substrate is disposed.

The module substrate is electrically connected to form a pair of terminals 1 and 2, a capacitor C1, a diode bridge 3, a switching element Q1, a resistor divider circuit 23, and a conversion unit 4, respectively. And a plurality of electronic components of the control circuit 6 and the power supply unit 7.

The material of the casing 15 is, for example, a material having higher thermal conductivity than the resin. A material having a higher thermal conductivity than the resin, such as aluminum.

The light source unit 5 includes a plurality of LEDs 9 , a metal base printed wiring board 18 electrically mounted with a plurality of LEDs 9 , and a fluorescent member 19 covering a plurality of LEDs 9 .

The luminescent color of the light source unit 5 is, for example, white. Each of the LEDs 9 is, for example, an LED chip that emits blue light. The connection relationship of the LEDs 9 can be, for example, a series connection, a parallel connection, a combination of a series connection and a parallel connection. The metal base printed wiring board 18 is thermally coupled to the casing 15 via the heat sink having electrical insulation and thermal conductivity on the one surface of the casing 15. The fluorescent member 19 is formed, for example, by a yellow phosphor that is excited by blue light emitted from each LED 9 and emits a broad spectrum of yellow light, and a mixture of a light-transmitting resin (hereinafter referred to as a first resin). The first resin is, for example, a silicone resin.

The material of the bulb 17 is, for example, a light transmissive material. The light transmissive material may be, for example, a resin having light transmissivity (hereinafter referred to as a second resin), glass, or the like. The second resin is, for example, an acrylic resin.

In the present embodiment, the LED light bulb 10 is exemplified as the LED light bulb, but is not limited thereto. The LED lighting device 10 may be, for example, an LED lighting device including an LED bulb and an appliance body that holds the LED bulb. LED lighting fixtures, such as ceiling lights.

The LED lighting device 10 of the present embodiment described above includes a pair of terminals 1 and 2, a diode bridge 3 for full-wave rectification of an alternating current voltage, and a converter unit 4 which is fully integrated by a diode bridge 3. The voltage of the wave rectification is converted to a predetermined DC voltage or a predetermined DC current. Further, the LED illumination device 10 includes a light source unit 5 that can be turned on by the predetermined DC voltage converted by the conversion unit 4 or the predetermined DC current, and the control circuit 6 to control the conversion unit 4. Further, the LED lighting device 10 includes a power supply unit 7, and supplies a first DC voltage to the control circuit 6 by generating a first DC voltage from the voltage of the full-wave rectification of the diode bridge 3. The light source unit 5 is provided with an LED 9. One pair of input terminals of the diode bridge 3 are respectively connected to the pair of terminals 1, 2. A capacitor C1 for removing noise is connected between the pair of input terminals. The diode bridge 3 is connected in parallel with the normally-off switching element Q1. The control circuit 6 includes a determination unit 8 having a function of determining a dimmer when the series circuit of the AC power source 20 and the dimmer 21 that outputs the AC voltage is connected between the pair of terminals 1 and 2; 21 is a first dimmer that performs phase control when the absolute value of the AC voltage is zero, and turns on the off state, and performs phase control to turn off the conduction state when the absolute value of the AC voltage is zero. Which of the second dimmers in the state is the dimmer; and the second function determines which state the dimmer 21 is in the on state and the off state. When the determination unit 8 determines that the dimmer 21 is the second dimmer, and the determination unit 8 determines that the dimmer 21 is turned off from the on state, the control unit 6 turns the switching element Q1 ON. . Thereby, the LED illumination device 10 can change the amount of light emitted from the light source unit 5 by the first dimmer that controls the AC voltage in the forward phase, and the second dimmer that controls the AC voltage in the reverse phase. The change in the amount of light emitted by the light source unit 5 is the same.

The control circuit 6 is configured to input a second DC voltage V1 corresponding to a voltage that is full-wave rectified by the diode bridge 3. The determination unit 8 includes a first determination unit 11 that determines whether the dimmer 21 is a dimmer of the first dimmer and the second dimmer, and a second determination unit 12 that determines the dimmer What is the state of the 21-series conduction state and the disconnection state. The first determination unit 11 is configured to determine which of the first dimmer and the second dimmer is the dimmer 21 based on the waveform of the second DC voltage V1. The second determination unit 12 is configured to determine which state the dimmer 21 is in the on state and the off state based on the second DC voltage V1. When the first determining unit 11 determines that the dimmer 21 is the second dimmer, and the second determining unit 12 determines that the dimmer 21 is in the off state, the control unit 6 causes the switching element to be turned off. Q1 is in the ON state. Thereby, the LED illumination device 10 can change the amount of light emitted from the light source unit 5 by the first dimmer that controls the AC voltage in the forward phase, and the second dimmer that controls the AC voltage in the reverse phase. The change in the amount of light emitted by the light source unit 5 is the same.

The control circuit 6 includes a differentiation circuit 13 that differentiates the second DC voltage V1. When the voltage value of the voltage V2 differentiated by the differentiating circuit 13 is greater than or equal to the threshold value Vth set in advance, the second determining unit 12 determines that the dimmer 21 is self-conducting. Cut off the state. Thereby, the second determination unit 12 can immediately determine when the dimmer 21 is in the off state from the on state.

The switching element Q1 is connected between one of the pair of output terminals of the diode bridge 3. Thereby, in the LED illumination device 10, as the switching element Q1, for example, a normally-off type n-channel MOSFET can be used.

The switching element Q1 is a normally-off type n-channel MOSFET. The first main terminal (the 汲 terminal in the present embodiment) of the switching element Q1 is connected to one of the pair of output ends of the diode bridge 3. The second main terminal (the source terminal in the present embodiment) of the switching element Q1 is connected to the other of the pair of output terminals. The control terminal (the gate terminal in the present embodiment) of the switching element Q1 is connected to the control circuit 6. In the LED lighting device 10, when the dimmer 21 of the second dimmer is turned off from the on state, the control circuit 6 can be accumulated in advance by turning on the switching element Q1. The charge of the capacitor C1 is discharged.

(Embodiment 2) The basic configuration of the LED illumination device 30 of the present embodiment is the same as that of the LED illumination device 10 of the first embodiment. However, as shown in Fig. 12, the switching element Q2 is connected to the diode bridge 3. The point between the pair of input terminals is different from that of the first embodiment. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be appropriately omitted.

The switching element Q2 includes a light emitting diode 14 and a photo triac 22 . The switching element Q2 is configured to optically couple the light emitting diode 14 to the optical bidirectional rectifier 22. As the switching element Q2, for example, an optical bidirectional rectifying coupler (for example, model number APT1221) manufactured by Panasonic Corporation may be used.

The anode of the light-emitting diode 14 is electrically connected to the control circuit 6. The cathode of the light-emitting diode 14 is electrically connected to the output terminal of the other of the diode bridges 3. In short, the cathode of the light-emitting diode 14 is connected to the low potential side of the output terminal of one of the diode bridges 3.

The first main terminal of the optical bidirectional rectifier 22 is electrically connected to one of the input terminals of the diode bridge 3. The second main terminal of the optical bidirectional rectifier 22 is electrically connected to the other input terminal of the diode bridge 3.

When the determination unit 8 determines that the dimmer 21 is the second dimmer, and the determination unit 8 determines that the dimmer 21 is turned off from the on state, the control circuit 6 supplies the light-emitting diode 14 The illuminating signal used for illuminating is output to the illuminating diode 14. In the switching element Q2, when the light-emitting diode 14 emits light, the optical bidirectional rectifier 22 is turned from the OFF state. As a result, when the dimmer 21 of the second dimmer is turned off from the on state, the LED illumination device 30 can discharge the electric charge accumulated in the capacitor C1 in advance. The electric charge accumulated in the capacitor C1 in advance is discharged by the switching element Q2 when the switching element Q2 is turned from the OFF state.

In the LED lighting device 30 of the present embodiment described above, the switching element Q2 is connected between one pair of input terminals of the diode bridge 3. Thereby, the LED lighting device 30 can quickly discharge the electric charge accumulated in the capacitor C1 in advance, for example, when the switching element Q2 is connected between the pair of output terminals of the diode bridge 3.

The switching element Q2 includes a light emitting diode 14 and an optical bidirectional rectifier 22. The switching element Q2 is configured to optically couple the light emitting diode 14 to the optical bidirectional rectifier 22. The anode of the light-emitting diode 14 is connected to the control circuit 6. The cathode of the light-emitting diode 14 is connected to the low potential side of the output terminal of one of the diode bridges 3 (the other output terminal of the diode bridge 3). The first main terminal of the optical bidirectional rectifier 22 is connected to one of the pair of input ends of the diode bridge 3. The second main terminal of the optical bidirectional rectifier 22 is connected to the other of the pair of input terminals. In the LED illumination device 30, when the dimmer 21 of the second dimmer is turned off from the on state, the control circuit 6 can be accumulated in advance by turning on the switching element Q2. The charge of the capacitor C1 is discharged.

1‧‧‧1st input terminal
2‧‧‧2nd input terminal
3‧‧‧Diode Bridge
4‧‧‧Transition Department
5‧‧‧Light source department
6‧‧‧Control circuit
7‧‧‧Power Supply Department
8‧‧‧Decision Department
9‧‧‧LED
10‧‧‧LED lighting device
11‧‧‧1st judgment department
12‧‧‧2nd Division
13‧‧‧Differential circuit
14‧‧‧Lighting diode
15‧‧‧Shell
16‧‧‧ lamp holder
17‧‧‧light ball
18‧‧‧Metal base printed wiring board
19‧‧‧Fluorescent components
20‧‧‧AC power supply
21‧‧‧Dimmer
22‧‧‧Light bidirectional rectifier
23‧‧‧Resistor voltage dividing circuit
30‧‧‧LED lighting device
C1‧‧‧ capacitor
D1～D4‧‧‧ diode
I1‧‧‧ input current
Q1, Q2‧‧‧ switching components
R1, R2‧‧‧ resistance
V1 ~ V3‧‧‧ voltage

Fig. 1 is a circuit diagram of an LED lighting device of the first embodiment. Fig. 2 is a circuit diagram showing a resistor divider circuit and a control circuit in the LED lighting device of the first embodiment. Fig. 3 is a view showing a first reference waveform previously stored in the control circuit in the LED lighting device of the first embodiment. Fig. 4 is a view showing a second reference waveform previously stored in the control circuit in the LED lighting device of the first embodiment. Fig. 5 is a view showing a state in which the switching element of the LED lighting device of the first embodiment is in an OFF state, and a voltage waveform of an input voltage of the LED lighting device and a current waveform of an input current of the LED lighting device. Fig. 6 is a view showing a state in which the switching element of the LED lighting device of the first embodiment is in an OFF state, and a voltage waveform of an input voltage of the LED lighting device and a current waveform of an input current of the LED lighting device. Fig. 7 is a view showing a voltage waveform of a second DC voltage and a voltage waveform of a voltage differentiated by a differentiation circuit in a case where the switching element is in an OFF state in the LED lighting device of the first embodiment. Fig. 8 is a graph showing the correlation between the conduction angle generated by the dimmer and the amount of light emitted from the light source unit in the case where the switching element is in the OFF state in the LED lighting device of the first embodiment. Fig. 9 is a view showing a state in which a switching element of the LED lighting device of the first embodiment is in an ON state, and a voltage waveform of an input voltage of the LED lighting device and a current waveform of an input current of the LED lighting device. Fig. 10 is a diagram showing the correlation between the conduction angle generated by the dimmer and the amount of light emitted from the light source unit in the case where the switching element is turned on in the LED lighting device of the first embodiment. Fig. 11 is a schematic side view showing a partially broken portion of the LED lighting device of the first embodiment. Fig. 12 is a circuit diagram of an LED lighting device of the second embodiment.

1‧‧‧1st input terminal

2‧‧‧2nd input terminal

3‧‧‧Diode Bridge

4‧‧‧Transition Department

5‧‧‧Light source department

6‧‧‧Control circuit

7‧‧‧Power Supply Department

8‧‧‧Decision Department

10‧‧‧LED lighting device

20‧‧‧AC power supply

21‧‧‧Dimmer

23‧‧‧Resistor voltage dividing circuit

C1‧‧‧ capacitor

D1~D4‧‧‧ Diode

I1‧‧‧ input current

Q1‧‧‧Switching elements

R1, R2‧‧‧ resistance

V1, V3‧‧‧ voltage

Claims (7)

An LED lighting device comprising: a pair of terminals; a diode bridge that rectifies the AC voltage full-wave; and a conversion unit that converts the voltage of the full-wave rectification of the diode bridge into a predetermined DC voltage or a predetermined one a direct current; a light source unit that can be turned on by the predetermined DC voltage converted by the conversion unit or the predetermined DC current; a control circuit that controls the conversion unit; and a power supply unit that is powered by the diode The full-wave rectified voltage of the bridge generates a first DC voltage, and the first DC voltage is supplied to the control circuit. The light source unit includes an LED; and one of the pair of diode bridges and the input end respectively A terminal is connected; a capacitor for removing noise is connected between the pair of input terminals; the diode bridge is connected in parallel with a normally-off type switching element; and the control circuit has a determining unit having the following functions: The first function determines that when the series circuit of the AC power source that outputs the AC voltage and the dimmer is connected between the pair of terminals, the dimmer performs phase control when the absolute value of the AC voltage is zero. guide Which dimmer is the first dimmer in the disconnected state and the second dimmer in which the phase is controlled to be in the off state when the absolute value of the AC voltage is zero; and a function of determining whether the dimmer is in an on state or a disconnected state; the control circuit determining, by the determining unit, the dimmer as the second dimmer, and the determining unit When it is determined that the dimmer is in the off state from the on state, the switching element is turned on. The LED lighting device of claim 1, wherein the control circuit is configured to input a second DC voltage corresponding to a voltage that is full-wave rectified by the diode bridge; the determining unit includes: The determining unit determines whether the dimmer is one of the first dimmer and the second dimmer, and the second determining unit determines that the dimmer is in an on state and a disconnected state Which state is determined by the first determining unit, based on the waveform of the second DC voltage, determining whether the dimmer is a dimmer of the first dimmer or the second dimmer; The second determination unit is configured to determine which state the dimmer is in an on state and a disconnection state based on the second DC voltage; and the control circuit determines the dimmer by the first determination unit When the second determining unit determines that the dimmer is turned off from the on state, the second determining unit turns the switching element into an ON state. The LED lighting device of claim 2, wherein the control circuit includes a differentiating circuit that differentiates the second DC voltage; and the second determining unit is configured to have a voltage value of a voltage differentiated by the differentiating circuit. When the value larger than the preset threshold value is equal to or lower than the threshold value, it is determined that the dimmer is turned off from the on state. The LED lighting device of any one of claims 1 to 3, wherein the switching element is connected between one pair of output ends of the diode bridge. The LED lighting device of claim 4, wherein the switching element is a normally-off type n-channel MOSFET; a first main terminal of the switching element and a pair of output ends of the diode bridge The output end of one of the switching elements is connected; the second main terminal of the switching element is connected to the other of the pair of output terminals; and the control terminal of the switching element is connected to the control circuit. The LED lighting device of any one of claims 1 to 3, wherein the switching element is connected between one of the pair of input terminals of the diode bridge. The LED lighting device of claim 6, wherein the switching element comprises a light emitting diode and an optical bidirectional rectifier, and the switching element is configured to optically couple the light emitting diode to the optical bidirectional rectifier; An anode of the light emitting diode is connected to the control circuit, and a cathode of the light emitting diode is connected to a low potential side of the output end of the diode bridge; a first main terminal of the optical bidirectional rectifier Connecting the input end of one of the pair of input ends of the diode bridge, and the second main terminal of the optical bidirectional rectifier is connected to the input end of the other of the pair of input terminals .