JP5311131B2 - Light emitting diode lighting device - Google Patents

Description

  The present invention relates to an illumination device capable of dimming an illumination light source, and more particularly, to an illumination device using a light emitting diode (LED) as an illumination light source, and to dimming the LED using a phase control type dimming circuit. It is related with the illuminating device which can be implemented.

  Conventionally, in a lighting device using an incandescent lamp as a light source for illumination, a phase control type dimming circuit that performs dimming using a bidirectional three-terminal thyristor (hereinafter simply referred to as a thyristor) has been widely used. The dimming circuit typically has power supplied to the light source by changing the duty ratio of the commercial AC power supply voltage supplied to the dimming circuit by controlling the conduction angle of the thyristor by the control unit. Dimming is performed by changing the amount.

  In recent years, various illuminating devices capable of dimming with such a phase control type dimming circuit have been proposed even in an illuminating device using a light emitting diode (LED) as a light source for illumination (for example, Patent Documents). 1-3). These lighting devices usually include a lighting circuit for outputting a driving current of the LED, and means for controlling the lighting circuit in accordance with the phase-controlled commercial AC power supply voltage and dimming the LED. Yes.

  For example, the lighting device described in Patent Literature 1 includes a lighting circuit composed of an insulating flyback converter and a conduction width detection circuit that detects a conduction width of a phase-controlled AC voltage. In response to the detection result, the dimming of the LED is performed by controlling the on-duty of the switching element of the lighting circuit. Further, in the lighting device described in Patent Document 2, a lighting circuit including an insulating flyback converter having an arithmetic circuit and an output control circuit on the secondary side, and half-wave conduction in each cycle of phase-controlled AC voltage It has a phase detection circuit that detects the angle, sends the detected conduction angle to the secondary side arithmetic circuit, sets the target current value of the output control circuit based on the arithmetic result, and the primary side of the lighting circuit The LED is dimmed by feedback control. The lighting device described in Patent Document 3 includes a lighting circuit composed of first and second switching elements that are PWM-controlled, and A / D conversion that converts a phase waveform of a commercial AC voltage waveform into a digital signal. A one-chip microcomputer provided with a circuit is further provided. The one-chip microcomputer further includes a PWM signal generation circuit. The PWM signal generates a first and a second in accordance with a voltage waveform A / D converted. The PWM dimming of the LED is performed by controlling the ON time of the switching element.

JP 2007-35403 A JP 2008-104273 A JP 2009-26544 A

  Generally, in the phase control type dimming circuit, there is a phenomenon in which the conduction angles of the positive and negative half-waves in each cycle do not match due to problems such as the electric characteristics of the dimming circuit and the sensitivity characteristics of the thyristor. The driving current supplied to the LED fluctuates finely every half cycle of positive and negative, and particularly when the LED is driven at a low output, there is a problem that the flickering of the light source is easily noticeable. In addition, this causes a problem that a light control range capable of stable light control is narrowed.

  In relation to this problem, in the illuminating device described in Patent Document 1, the conduction width detection circuit converts the phase-controlled AC voltage into a rectangular wave pulse, and then smoothes the DC voltage by the RC filter circuit. Although it has a configuration, this configuration has a problem that control responsiveness to a change in the degree of dimming is low in use at a frequency of about commercial frequency (50 Hz or 60 Hz). Further, since this lighting device is configured to detect the conduction width of the phase-controlled AC voltage, even when the dimming circuit is set to the same conduction angle, for example, 50 Hz and 60 Hz are applied. There is a problem that the brightness of the LED changes if the commercial frequency is different.

  Further, the lighting device described in Patent Document 2 detects the conduction angle of only one half wave in each cycle of the phase-controlled AC voltage in the phase detection circuit (the other half wave is detected). This is to deal with the problem of variation in conduction angle between positive and negative half-waves. However, in this configuration, when two power supply devices each including a lighting circuit and a phase detection circuit are connected to one dimming circuit, each half-wave is detected by each phase detection circuit, and thereby each lighting There is a problem that the brightness of the LEDs connected to the circuit is different. Furthermore, this lighting device has an arithmetic circuit and an output control circuit on the secondary side of the lighting circuit, sends the conduction angle detected by the phase detection circuit to the secondary side arithmetic circuit, and the calculation result Since the reference current value of the output control circuit is set based on the above and the primary side of the lighting circuit is feedback-controlled, there is a problem that the circuit scale increases.

  Moreover, although the illuminating device described in patent document 3 is an illuminating device which can light-control LED according to the control of the conduction angle in a light control circuit, each cycle of the phase-controlled alternating voltage as mentioned above No consideration is given to the point at which the conduction angles of the positive and negative half-waves do not match and cause flickering of the light source. Further, since this lighting device performs dimming of the LED by so-called PWM dimming that adjusts the blinking duty ratio, normally, although flickering is not visually felt, the lighting device blinks. There is a possibility that fatigue will accumulate in the eyes.

  The present invention has been made in view of the above problems, and provides an illumination device capable of dimming control of a direct current supplied to an LED in accordance with a conduction angle of a phase-controlled alternating voltage with high accuracy. The purpose is to do.

  The following aspects of the present invention exemplify the configuration of the present invention, and will be described separately for easy understanding of various configurations of the present invention. Each section does not limit the technical scope of the present invention, and some of the components of each section are replaced, deleted, or further, while referring to the best mode for carrying out the invention. Those to which the above components are added can also be included in the technical scope of the present invention.

(1) A dimming circuit that controls the phase of the current supplied to the light emitting diode by controlling the conduction angle of the alternating current supplied from the light emitting diode and the commercial AC power supply, and the alternating current output from the dimming circuit A rectifying circuit that rectifies the voltage, a smoothing circuit that smoothes a DC voltage output from the rectifying circuit, and a lighting circuit that outputs a DC current that causes the light emitting diode to emit light according to the voltage smoothed by the smoothing circuit In a light emitting diode illuminating device that controls dimming of the light emitting diode, the voltage waveform output from the rectifier circuit is formed into a substantially rectangular wave shape, disposed between the rectifier circuit and the smoothing circuit. The conduction angle waveform shaping circuit to be performed and the output signal from the conduction angle waveform shaping circuit are input, and the waveform data for two consecutive half cycles is set as one unit of waveform data. Both the conduction angle detection circuit for calculating the average value of the waveform data of one unit, the control signal calculation circuit for calculating the control signal by inputting the output signal of the conduction angle detection circuit, and the output of the control signal calculation circuit A control signal generating circuit that inputs a signal and outputs a control signal to the lighting circuit, and the lighting circuit detects a current flowing through the light emitting diode and feeds it back to the control signal arithmetic circuit And the control signal calculation circuit calculates a control signal for causing a predetermined current to flow through the light emitting diode based on an output signal of the conduction angle detection circuit and a feedback signal from the current detection circuit. A light-emitting diode illuminating device.

(2) In the light-emitting diode illuminating device according to item (1), the lighting circuit supplies a continuous DC current to the light-emitting diode, and the DC current is supplied in accordance with a control signal input from the control signal generation circuit. A light-emitting diode illuminating device, wherein the light-emitting diode is current-modulated by changing the current.

(3) The light-emitting diode illuminating device according to (1) or (2), wherein the average value is a moving average value.

(4) In the light-emitting diode illuminating device according to any one of (1) to (3), the lighting circuit includes a DC-DC converter, and the conduction angle detection circuit includes the conduction angle waveform shaping circuit. A first A / D converter circuit that receives the output signal of the first A / D converter, and an average value circuit that receives the signal from the first A / D converter circuit and calculates an average value of at least one unit of waveform data. A light-emitting diode illuminating device comprising:

(5) In the light-emitting diode illuminating device according to the item (4), the DC-DC converter is a non-insulated type, and the detection current detected by the current detection circuit passes through a second A / D conversion circuit. A light-emitting diode illuminating device fed back to the control signal arithmetic circuit.

(6) In the light-emitting diode illuminating device according to (5), the conduction angle detection circuit including at least the first A / D conversion circuit and the average value circuit, the control signal calculation circuit, and the control signal A light-emitting diode illuminating device comprising a one-chip microcomputer in which a generation circuit and the second A / D conversion circuit are integrated.

(7) In the light-emitting diode illuminating device according to (4), the DC-DC converter is an insulation type, and the detected current detected by the current detection circuit is a digital signal generation circuit, an insulation circuit, and a digital signal reception. A light-emitting diode illuminating device fed back to the control signal arithmetic circuit via a circuit.

(8) In the light-emitting diode illuminating device according to (7), the digital signal generation circuit includes a comparator that inputs a detection current and a carrier signal detected by the current detection circuit and outputs a pulse signal. A light-emitting diode illumination device.

(9) In the light-emitting diode illuminating device according to item (7), the digital signal generation circuit includes a third A / D conversion circuit that inputs a detection current detected by the current detection circuit, and the third A / D conversion circuit. A light-emitting diode illuminating device comprising: a PWM signal generation circuit that inputs an output signal from an A / D conversion circuit and outputs a pulse signal.

(10) In the light-emitting diode illuminating device according to item (7), the digital signal generation circuit includes a fourth A / D conversion circuit for inputting a detection current detected by the current detection circuit, and the fourth A / D conversion circuit. A light-emitting diode illuminating device comprising a communication signal generation circuit for inputting an output signal from an A / D conversion circuit and outputting a pulse signal.

(11) In the light-emitting diode illuminating device according to item (7), the conduction angle detection circuit including at least the first A / D conversion circuit and the average value circuit, the control signal calculation circuit, and the control signal A light-emitting diode illuminating device comprising a one-chip microcomputer in which a generation circuit and the digital signal receiving circuit are integrated.

(12) In the light-emitting diode illuminating device according to (6) or (11), the one-chip microcomputer outputs a control signal for obtaining a desired dimming characteristic by rearranging software for executing the operation. A light-emitting diode illuminating device.

  The present invention provides a lighting device capable of dimming and controlling the DC current supplied to the LED with high accuracy in accordance with the conduction angle of the AC voltage subjected to phase control. Is possible.

It is a circuit block diagram of the light emitting diode illuminating device in 1st Embodiment of this invention. In the light emitting diode illuminating device shown in FIG. 1, it is a figure which shows the current waveform of each point. It is a circuit block diagram of the light emitting diode illuminating device in 2nd Embodiment of this invention. It is a circuit block diagram of the light emitting diode illuminating device in 3rd Embodiment of this invention. FIG. 5 is a diagram illustrating a specific configuration example of a digital signal generation circuit in the light-emitting diode illuminating device illustrated in FIG. 4, where (a) illustrates a configuration example using a comparator, and (b) illustrates a PWM signal generation circuit. Configuration example, (c) is a circuit configuration diagram showing a configuration example using a communication signal generation circuit.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
(First embodiment)
A light emitting diode (LED) lighting device (hereinafter also simply referred to as a lighting device) 1 shown in FIG. 1 has a conduction angle of alternating current supplied from a light emitting diode (LED) module 7 that is a light source for illumination and a commercial AC power supply Vac. The dimming circuit 2 that controls the phase of the current supplied to the LED module 7 by controlling, the rectifying circuit 3 that rectifies the AC voltage output from the dimming circuit 2, and the DC voltage output from the rectifying circuit 3 And a lighting circuit 6 that causes the LED module 7 to emit light in accordance with the voltage smoothed by the smoothing circuit 5. In the present embodiment, the LED module 7 is formed by connecting a plurality of individual LED elements in series. However, the configuration of the LED module 7 in the lighting device 1 according to the present invention is limited to this mode. It is not intended to include any illumination light source composed of one or more LED elements.

  Here, the dimming circuit 2 includes a thyristor Q0, and typically supplies a trigger to the thyristor Q0 at a predetermined conduction angle of the commercial AC power supply Vac to turn on the thyristor Q0. A control unit (not shown) and a variable resistor for changing the degree of dimming of the LED 7 by setting the predetermined conduction angle in various ways are included.

  The rectifier circuit 3 is a full-wave rectifier circuit configured as a known diode bridge including four diodes D1 to D4, and the smoothing circuit 5 includes a diode D5 and a capacitor C1. The lighting circuit 6 is a non-insulated DC-DC converter having a switching element Q1 made of, for example, a MOS-FET, a diode D6, a choke coil L1, and a capacitor C2, and a control signal from a control signal generation circuit 10 described later. Based on the above, an appropriate direct current is output to the LED module 7. The lighting circuit 6 includes a current detection circuit (detection resistor) R1 that detects a direct current flowing through the LED module 7 and feeds it back to a control signal calculation circuit 9 described later.

  The illuminating device 1 in the present embodiment includes a conduction angle waveform shaping circuit 4 that shapes a voltage waveform output from the rectifier circuit 3 into a substantially rectangular wave shape between the rectifier circuit 3 and the smoothing circuit 5. Specifically, as shown in FIG. 2, the AC waveform (A) supplied from the commercial AC power supply Vac has a conduction angle (90 ° to 180 ° in the example of FIG. 2) set in the dimming circuit 2. And a waveform (B) having 270 ° to 360 °), and further converted into a pulsating flow waveform (C) having the same conduction angle by the rectifier circuit 3. Then, the conduction angle waveform shaping circuit 4 shapes the output voltage waveform from the rectifier circuit 3 into a substantially rectangular wave shape having a pulse width corresponding to each conduction angle (C). In this example, a rectangular wave having a pulse width t1-t2 is equivalent to a waveform for a positive half cycle having a conduction angle of 90 ° to 180 °, and a rectangular wave having a pulse width t3-t4 is equivalent to a conduction angle of 270 ° to Equivalent to a 360 ° negative half-cycle waveform.

  Further, the lighting device 1 receives the output signal from the conduction angle waveform shaping circuit 4 and sets the waveform data for two consecutive half cycles as one unit of waveform data, and an average value of at least one unit of waveform data. The conduction angle detection circuit 8 for calculating the control signal, the output signal of the conduction angle detection circuit 8 is input, the control signal calculation circuit 9 for calculating the control signal, the output signal of the control signal calculation circuit 9 is input, and the lighting circuit 6 has a control signal generation circuit 10 for outputting a control signal.

  The conduction angle detection circuit 8 has, for example, a rectangular wave (for example, a pulse width t1-t2 in the example of FIG. 2) equivalent to a waveform corresponding to a positive half cycle in a waveform of one cycle, for each input waveform of each cycle. The waveform data of a rectangular wave (a rectangular wave having a pulse width of t3 to t4 in the example of FIG. 2) equivalent to the waveform of a negative half cycle and a rectangular wave is defined as one unit of waveform data, and the average for this one unit. The value is calculated and the waveform data of the averaged rectangular wave is output.

  Here, one unit of waveform data is a rectangular wave equivalent to the waveform of the negative half cycle in the waveform of one cycle and a rectangular wave equivalent to the waveform of the positive half cycle in the waveform of the next one cycle. The average value may be calculated using waveform data of 2 units or more. Further, the average value of the waveform data is obtained by using, as one unit of waveform data, waveform data of a rectangular wave equivalent to a waveform for a positive half cycle in a waveform of one cycle and a rectangular wave equivalent to a waveform for a negative half cycle, The average value is calculated, and then the rectangular wave waveform data equivalent to the waveform for the negative half cycle used for the calculation of the average value, and the rectangular waveform equivalent to the waveform for the positive half cycle in the next one cycle It may be a so-called moving average value obtained by repeating calculations such as calculating the average value of the waveform data of the wave as one unit of waveform data.

  The control signal calculation circuit 9 receives the output signal of the conduction angle detection circuit 8 which is the waveform data averaged in this way, and the current value flowing through the LED module 7 detected by the current detection circuit R1. Is fed back, and the control signal calculation circuit 9 calculates a control signal for causing a predetermined current to flow through the LED module 7 based on these.

  Although the present invention is not limited to a specific mode of the control signal calculation circuit 9, for example, the control signal calculation circuit 9 holds a target current value to be passed through the LED module 7 according to the conduction angle. The target current value corresponding to the conduction angle obtained from the waveform data input from the conduction angle detection circuit 8 is compared with the current value fed back from the current detection circuit R1, and the output current of the lighting circuit 6 is compared. An increase, decrease, or status quo is discriminated, and an output signal for instructing the control signal generation circuit 10 to generate an appropriate control signal is generated according to the result, and output to the control signal generation circuit 10. .

  In the present embodiment, the control signal output from the control signal generation circuit 10 to the lighting circuit 6 is a gate voltage signal for driving the switching element Q1 of the lighting circuit 6, and the control signal generation circuit 10 performs control signal calculation. Based on the signal input from the circuit 9, an appropriate gate voltage signal is generated, for example, the output current of the lighting circuit 6 is adjusted by changing the on-duty of the switching element Q1, and the dimming of the LED module 7 is adjusted. To implement. That is, the control signal generation circuit 10 increases the on-duty of the switching element Q1 when the signal from the control signal calculation circuit 9 instructs to increase (or decrease) the output current of the lighting circuit 6. A control signal to be (or decreased) is generated and output to the switching element Q1 of the lighting circuit 6.

  As described above, the lighting circuit 6 supplies the LED module 7 with a continuous DC current, and changes the DC current in accordance with the control signal input from the control signal generation circuit 10 to thereby change the LED module 7 into a current. Light control.

  The lighting device 1 according to the present embodiment uses two consecutive half-cycle waveform data as one unit of waveform data, calculates an average value of at least one unit of waveform data, and generates a control signal based on the average value. Therefore, due to problems such as the electrical characteristics of the dimming circuit 2 and the sensitivity characteristics of the thyristor Q0, high responsiveness to changes in dimming can be achieved even when the actual conduction angles of the positive and negative half cycles in each cycle do not match. High-precision light control can be performed while being held, flickering of LED module 7 and variations in luminance can be prevented, and the light control range can be expanded. At this time, it is possible to further increase the light control accuracy by increasing the number of units of the waveform data to be averaged. If the moving average value is used as the average value, the light control can be moderated by smoothing the transition of the average value.

  Moreover, in the illuminating device 1 in this embodiment, the waveform data for two continuous half cycles are set as one unit of waveform data, and the average value of at least one unit of waveform data is calculated. The brightness of the LED module 7 is the same even if the input connection of the subsequent circuit connected to is reversed. In addition, since the conduction angle is used for control, the brightness is the same even when the commercial frequency is different, and the versatility is high, compared to the case where the conduction width is used for control. Furthermore, since current dimming is performed and the LED module 7 does not blink, there is less eye fatigue compared to PWM dimming.

(Second Embodiment)
Next, the light-emitting diode illuminating device 1a according to the second embodiment of the present invention will be described. In the following, components corresponding to the components of the illuminating device 1 according to the first embodiment described above are denoted by the same reference numerals. Therefore, the description of the parts common to the lighting device 1 in the first embodiment will be omitted as appropriate, and the differences will be mainly described.

  As shown in FIG. 3, in the illuminating device 1 a according to the present embodiment, the conduction angle detection circuit 8 a includes a first A / D conversion circuit 11 and an average value circuit 12. The waveform data of the input substantially rectangular wave pulse (see D in FIG. 2) is input to the first A / D conversion circuit 11 and converted into digital data, and then the average value circuit 12 performs each cycle. An average value of at least one unit of waveform data is calculated as digital data. The conduction angle detection circuit 8a, the control signal calculation circuit 9, and the control signal generation circuit 10 are integrated in a one-chip microcomputer 14.

  The detected current of the current detection circuit (detection resistor) R1 is input to the second A / D conversion circuit 13 and converted into digital data, and then fed back to the control signal calculation circuit 9. In the present embodiment, the second A / D conversion circuit 13 is also integrated in the one-chip microcomputer 14.

  In the present embodiment, each circuit integrated in the one-chip microcomputer 14 does not need to be implemented as hardware for executing a specific function, and each circuit is built in the one-chip microcomputer 14. Alternatively, it may be stored in a connected storage means and may include software that executes all or part of the function of each circuit. In the present embodiment, the term “circuit” integrated in the one-chip microcomputer 14 is used in this sense.

The lighting device 1a in the present embodiment has the same effects as the lighting device 1 in the first embodiment described above, and in addition, its conduction angle detection circuit 8a, control signal arithmetic circuit 9, and control signal generation circuit 10 Is integrated in the one-chip microcomputer 14, the number of parts can be reduced, and the desired dimming characteristics can be easily adjusted by rearranging software for executing the one-chip microcomputer 14.

(Third embodiment)
Next, the light-emitting diode illuminating device 1b according to the third embodiment of the present invention will be described. In the following, components corresponding to the components of the illuminating device 1 according to the first embodiment described above are denoted by the same reference numerals. Therefore, the description of the parts common to the lighting device 1 in the first embodiment will be omitted as appropriate, and the differences will be mainly described.

  As shown in FIG. 4, in the illuminating device 1b according to the present embodiment, the lighting circuit 6a is an insulated DC-DC converter having a switching element Q1 made of, for example, a MOS-FET, a diode D6, a high-frequency transformer T1, and a capacitor C2. Yes, based on a control signal from the control signal generation circuit 10, an appropriate direct current is output to the LED module 7 connected to the secondary side of the lighting circuit 6a. Further, a current detection circuit (detection resistor) R1 for detecting a current flowing through the LED module 7 is provided on the secondary side of the lighting circuit 6a.

  Furthermore, in the illuminating device 1b, the conduction angle detection circuit 8a includes a first A / D conversion circuit 11 and an average value circuit 12, and a substantially rectangular wave-shaped pulse (see FIG. 5) input from the conduction angle waveform shaping circuit 4. 2 (see D of 2) is input to the first A / D conversion circuit 11 and converted into digital data, and then the average value of the waveform data of at least one unit for each cycle is obtained by the average value circuit 12. Calculated as digital data. The conduction angle detection circuit 8a, the control signal calculation circuit 9, and the control signal generation circuit 10 are integrated in the one-chip microcomputer 14a and connected to the primary side of the lighting circuit 6a.

  The detection current of the current detection circuit (detection resistor) R1 provided on the secondary side of the high-frequency transformer T1 is converted into digital data by the digital signal generation circuit 15 and then passed through an insulation circuit 16 made of, for example, a photocoupler. And input to the one-chip microcomputer 14a on the primary side. A digital signal receiving circuit 17 for receiving a detection current converted into digital data is also integrated in the one-chip microcomputer 14a, and the detection current is fed back to the control signal calculation circuit 9 via the digital signal receiving circuit 17. Is done.

  In the present embodiment, each circuit integrated in the one-chip microcomputer 14a does not need to be mounted as hardware for executing a specific function, and each circuit is built in the one-chip microcomputer 14a. Alternatively, it may be stored in a connected storage means and may include software that executes all or part of the function of each circuit. In the present embodiment, the term “circuit” integrated in the one-chip microcomputer 14a is used in this sense.

  Here, a specific configuration example of the digital signal generation circuit 15 will be described with reference to FIG. The circuit shown in FIG. 5A includes a comparator 18, and the non-inverting input terminal (+) of the comparator 18 is detected by the current detection circuit R1 (that is, converted into a voltage value by the current detection circuit R1). Detection current) is input, and a carrier signal composed of a triangular wave or a sawtooth wave is input to the inverting input terminal (−). As a result, pulse signals having different pulse widths are output to the output terminal of the comparator 18 in accordance with the magnitude of the detected current. In the circuit shown in FIG. 5B, the third A / D conversion circuit 19 that inputs the detection current detected by the current detection circuit R1 and the output signal from the third A / D conversion circuit 19 are input. PWM signal generation circuit 20 is provided, and pulse signals having different pulse widths are output according to the magnitude of the detected current. In the circuit shown in FIG. 5C, the fourth A / D conversion circuit 21 that inputs the detection current detected by the current detection circuit R1 and the output signal from the fourth A / D conversion circuit 21 are input. The communication signal generating circuit 22 is provided. The communication signal generation circuit 22 is a communication signal generation circuit for serial communication, for example, and outputs a pulse signal based on the specification of serial communication to be used.

  The lighting device 1b in the present embodiment has the same effects as the lighting device 1 in the first embodiment described above, and in addition, the conduction angle detection circuit 8a, the control signal calculation circuit 9, and the control signal generation circuit 10 Is integrated in the one-chip microcomputer 14a, the number of parts can be reduced, and the desired dimming characteristics can be easily adjusted by rearranging software for executing the one-chip microcomputer 14a. Further, in a configuration in which the lighting circuit 6a is an isolated DC-DC converter, a conduction angle detection circuit 8a, a control signal calculation circuit 9, and a control signal generation circuit 10 for performing dimming control are replaced with a one-chip microcomputer 14a. Are provided on the primary side of the lighting circuit 6a, so that the dimming control can be performed with a relatively simple circuit. At this time, the detection current detected by the current detection circuit R1 is converted into digital data by the digital signal generation circuit 15, so that it can be easily and reliably fed back to the primary side.

As mentioned above, although this invention was demonstrated by preferable embodiment, this invention is not limited to embodiment mentioned above, A various deformation | transformation and application are possible within the range of the technical idea of this invention. For example, in the lighting device 1b according to the third embodiment, the insulating circuit 16 is a photocoupler, but is not limited thereto, and may be another insulating circuit such as an insulating transformer.
Moreover, in the illuminating devices 1, 1a, and 1b in the first to third embodiments described above, the rectifier circuit 3 is a full-wave rectifier circuit configured as a diode bridge, but is not limited thereto. The rectifier circuit may be used.

DESCRIPTION OF SYMBOLS 1, 1a, 1b: Light-emitting diode illuminating device, 2: Light control circuit, 3: Rectification circuit, 4: Conduction angle waveform formation circuit, 5: Smoothing circuit, 6, 6a: Lighting circuit, 7: Light-emitting diode (LED) module 8, 8a: conduction angle detection circuit, 9: control signal calculation circuit, 10: control signal generation circuit, 11: first A / D conversion circuit, 12: average value circuit, 13: second A / D conversion Circuit: 14, 14a: 1 chip microcomputer, 15: digital signal generation circuit, 16: insulation circuit, 17: digital signal reception circuit, 18: comparator, 19: third A / D conversion circuit, 20: PWM signal generation Circuit, 21: fourth A / D conversion circuit, 22: communication signal generation circuit, C1, C2: capacitor, D1, D2, D3, D4, D5, D6: diode, L1: choke coil, T1: high-frequency transistor , Q0: bidirectional three-terminal thyristor (thyristor), Q1: Switching element, R1: a current detection circuit (detection resistor), Vac: commercial AC power source

Claims (12)

A dimming circuit that controls the phase of the current supplied to the light emitting diode by controlling the conduction angle of the alternating current supplied from the light emitting diode and the commercial AC power supply, and rectifies the AC voltage output from the dimming circuit A rectifying circuit for smoothing, a smoothing circuit for smoothing a DC voltage output from the rectifying circuit, and a lighting circuit for outputting a DC current for causing the light-emitting diode to emit light according to the voltage smoothed by the smoothing circuit. In the light emitting diode illuminating device for controlling the dimming of the light emitting diode,
A conduction angle waveform shaping circuit which is arranged between the rectification circuit and the smoothing circuit and shapes the voltage waveform output from the rectification circuit into a substantially rectangular wave shape, and an output signal from the conduction angle waveform shaping circuit A conduction angle detection circuit that calculates the average value of at least one unit of waveform data, and outputs an output signal of the conduction angle detection circuit, by inputting the waveform data for two consecutive half cycles as one unit of waveform data. And a control signal generating circuit for calculating the control signal and a control signal generating circuit for inputting the output signal of the control signal calculating circuit and outputting the control signal to the lighting circuit, and the lighting circuit Includes a current detection circuit that detects a current flowing through the light emitting diode and feeds back the current to the control signal calculation circuit. The control signal calculation circuit is connected to the output signal of the conduction angle detection circuit. Based on the feedback signal from the current detection circuit, the light-emitting diode illuminating device, characterized by calculating a control signal for supplying a predetermined current to the light emitting diode.   The lighting circuit supplies a continuous direct current to the light emitting diode, and changes the direct current according to a control signal input from the control signal generation circuit, thereby dimming the light emitting diode. The light-emitting diode illuminating device according to claim 1.   The light emitting diode illumination device according to claim 1, wherein the average value is a moving average value.   The lighting circuit includes a DC-DC converter, and the conduction angle detection circuit includes a first A / D conversion circuit that inputs an output signal from the conduction angle waveform shaping circuit, and the first A / D conversion. 4. The light-emitting diode illuminating apparatus according to claim 1, further comprising an average value circuit that inputs a signal from the circuit and calculates an average value of at least one unit of waveform data. 5.   The DC-DC converter is a non-insulated type, and a detection current detected by the current detection circuit is fed back to the control signal calculation circuit via a second A / D conversion circuit. 5. The light-emitting diode illuminating device according to 4.   The conduction angle detection circuit including at least the first A / D conversion circuit and the average value circuit, the control signal calculation circuit, the control signal generation circuit, and the second A / D conversion circuit are integrated. 6. The light-emitting diode illuminating device according to claim 5, further comprising a one-chip microcomputer.   The DC-DC converter is an insulation type, and a detection current detected by the current detection circuit is fed back to the control signal calculation circuit via a digital signal generation circuit, an insulation circuit, and a digital signal reception circuit. The light-emitting diode illuminating device according to claim 4.   The light emitting diode illuminating apparatus according to claim 7, wherein the digital signal generation circuit includes a comparator that inputs a detection current detected by the current detection circuit and a carrier signal and outputs a pulse signal.   The digital signal generation circuit inputs a detection signal detected by the current detection circuit, a third A / D conversion circuit, and an output signal from the third A / D conversion circuit to input a pulse signal. The light-emitting diode illuminating apparatus according to claim 7, further comprising a PWM signal generation circuit for outputting.   The digital signal generation circuit inputs a detection signal detected by the current detection circuit, a fourth A / D conversion circuit, and an output signal from the fourth A / D conversion circuit to input a pulse signal The light emitting diode illuminating device according to claim 7, further comprising a communication signal generating circuit for outputting.   One chip in which the conduction angle detection circuit including at least the first A / D conversion circuit and the average value circuit, the control signal calculation circuit, the control signal generation circuit, and the digital signal reception circuit are integrated. The light-emitting diode illuminating apparatus according to claim 7, further comprising a microcomputer.   12. The light-emitting diode illuminating apparatus according to claim 6, wherein the one-chip microcomputer can output a control signal for obtaining a desired dimming characteristic by rearranging software for executing the operation.

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