JP2018201298A - Light source lighting device and lighting apparatus - Google Patents

Abstract

To provide a light source lighting device and a lighting apparatus receiving power from a DC power source, capable of reducing flickering of a light source due to power supply fluctuation and reducing in-rush current, and capable of downsizing.SOLUTION: A light source lighting device 1 according to the present invention includes: a lighting circuit 14 receiving power from a DC power source 100 to light a light source; and a flickering reduction circuit 2 connected in parallel with the DC power source between the DC power source and the lighting circuit. The flickering reduction circuit includes: a capacitive element 6; an impedance element 4 connected in series with the capacitive element on the high potential side of the capacitive element; and a first diode 5 whose anode is connected to a junction of the impedance element and the capacitive element, and whose cathode is connected on the high potential side of the lighting circuit.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light source lighting device and a lighting fixture that receive power from a DC power source.

  Patent Document 1 discloses a light source lighting device and a lighting fixture to which DC power is supplied from a DC power source. Moreover, the power supply device shown in Patent Document 2 includes a smoothing element for smoothing or storing DC power from a DC power supply. In Patent Document 2, an inrush current prevention circuit is provided in the power supply device in order to suppress an inrush current flowing through the smoothing element when the power is turned on. This inrush current prevention circuit has a parallel circuit of a resistor and a thyristor as a current limiting element between a DC power source and a smoothing element. The inrush current when the power is turned on is suppressed by the resistor, and when the oscillation of the power supply circuit starts, the thyristor is turned on to bypass the resistor.

Japanese Patent No. 5199658 JP 2013-70583 A

  In a DC power supply, power supply fluctuation may occur due to a short-time power supply voltage drop or interruption due to an abnormality in the DC power supply. In a lighting fixture that uses a DC power source as a power source, flicker may occur in the light source due to fluctuations in the power source. In order to suppress flickering of the light source, it is effective to provide a capacitive element in the light source lighting device. Thus, the light source can be kept on with the electric power stored in the capacitive element during a short-time power fluctuation.

  Here, as shown in Patent Document 2, an inrush current may flow through the capacitive element when the power is turned on. For this reason, when a capacitive element is provided in the light source lighting device, an inrush current suppression circuit is generally required. For this reason, the circuit for suppressing the flickering of the light source with respect to a short-time power supply fluctuation may increase in size and cost.

  The present invention has been made to solve the above-described problems, and is to obtain a light source lighting device and a lighting fixture capable of suppressing flickering of a light source and inrush current with respect to power supply fluctuation and capable of being downsized. Objective.

  A light source lighting device according to the present invention includes a lighting circuit that turns on a light source by receiving power from a DC power source, a flicker suppression circuit that is connected in parallel with the DC power source between the DC power source and the lighting circuit, The flicker suppression circuit includes a capacitive element, an impedance element connected in series with the capacitive element on a high potential side of the capacitive element, and a connection point between the impedance element and the capacitive element. A first diode having an anode connected thereto and a cathode connected to a high potential side of the lighting circuit.

  In the light source lighting device according to the present invention, the electric power from the DC power source is stored in the capacitive element via the impedance element. For this reason, inrush current can be suppressed. Further, when the DC power supply is cut off or lowered, the power stored in the capacitive element is supplied to the light source side via the first diode. For this reason, flicker can be suppressed. Further, since the inrush current and the flicker can be suppressed with a simple configuration, the light source lighting device can be downsized.

2 is a circuit block diagram of the lighting fixture according to Embodiment 1. FIG. 3 is a circuit block diagram of a lighting fixture according to a comparative example of Embodiment 1. FIG. It is a figure which shows the current voltage waveform at the time of power activation of the lighting fixture which concerns on the comparative example of Embodiment 1. FIG. It is a figure which shows the current voltage waveform at the time of power activation of the lighting fixture which concerns on Embodiment 1. FIG. It is a figure which shows the current voltage waveform at the time of the power supply fluctuation | variation of the lighting fixture which concerns on the comparative example of Embodiment 1. FIG. It is a figure which shows the current voltage waveform at the time of the power supply fluctuation | variation of the lighting fixture which concerns on Embodiment 1. FIG.

  A light source lighting device and a lighting fixture according to an embodiment of the present invention will be described with reference to the drawings. The same or corresponding components are denoted by the same reference numerals, and repeated description may be omitted.

Embodiment 1 FIG.
FIG. 1 is a circuit block diagram of a lighting fixture 80 according to the first embodiment. The lighting fixture 80 includes the light source lighting device 1 and the light source 200. In FIG. 1, components other than the DC power source 100 and the light source 200 are components of the light source lighting device 1. The light source lighting device 1 includes a flicker suppression circuit 2 and a lighting device 14. The lighting device 14 includes a lighting circuit 16, a control unit 13, and a drive circuit 8. The lighting circuit 16 is supplied with electric power from the DC power supply 100 and turns on the light source 200.

  The DC power supply 100 supplies DC power to the light source lighting device 1. The DC power supply 100 is a battery, for example. The DC power supply 100 may be a power supply obtained by rectifying an AC power supply. Here, the AC power supply may be a commercial power supply. The DC power supply 100 has a positive polarity which is an output on the high potential side and a negative polarity which is an output on the low potential side. The output on the high potential side of the DC power supply 100 is connected to the connector T1 of the light source lighting device 1. The output on the low potential side of the DC power supply 100 is connected to the connector T2 of the light source lighting device 1.

  The light source 200 includes, for example, a plurality of LEDs connected in series. However, the light source 200 may include at least one LED. Further, the plurality of LEDs may be connected in parallel or in series-parallel. However, the present invention is not limited to this, and the light source 200 only needs to include a light emitting element. For example, the light source 200 may include an organic EL or a fluorescent lamp.

  The flicker suppression circuit 2 is connected in parallel with the DC power supply 100 between the DC power supply 100 and the lighting circuit 16. The flicker suppression circuit 2 includes a series circuit 20. The series circuit 20 is connected in parallel with the DC power supply 100. The series circuit 20 includes a capacitive element 6 and an impedance element 4 connected in series with the capacitive element 6. The impedance element 4 is connected to the high potential side of the capacitive element 6.

  In the present embodiment, the impedance element 4 is a resistor, for example. However, the impedance element 4 may be other than a resistor as long as it has an impedance component. The capacitive element 6 is a capacitor, for example. In the present embodiment, the capacitive element 6 is an electrolytic capacitor having polarity. The high potential side of the capacitive element 6 has a positive polarity. The low potential side of the capacitive element is negative. The capacitive element 6 may be a nonpolar capacitor. However, the capacitive element 6 may be other than a capacitor as long as it has a capacitance.

  The flicker suppression circuit 2 includes a first diode 5. The anode of the first diode 5 is connected to a connection point between the impedance element 4 and the capacitive element 6. The cathode of the first diode 5 is connected to the high potential side of the lighting circuit 16. The cathode of the first diode 5 is connected to one end of the impedance element 4, the cathode of the second diode 3, and the high potential side input of the lighting device 14.

  The flicker suppression circuit 2 further includes a second diode 3. The anode of the second diode 3 is connected to the high potential side output of the DC power supply 100 via the connector T1. The cathode of the second diode 3 is connected to the high potential side of the series circuit 20. One end on the high potential side of the impedance element 4, the cathode of the first diode 5, and the high potential side input of the lighting device 14 are connected to the cathode of the second diode 3.

  The lighting circuit 16 includes a switching element 7. The drain of the switching element 7 is connected to an input on the high potential side of the lighting device 14. The source of the switching element 7 is connected to the cathode of the diode 11 and one end of the inductor 9. The gate of the switching element 7 is connected to the drive circuit 8. The anode of the diode 11 is connected to the output on the low potential side of the DC power supply 100. The other end of the inductor 9 is connected to the positive electrode of the capacitor 10 and the connector T3. The negative electrode of the capacitor 10 is connected to the output on the low potential side of the DC power supply 100.

  The light source lighting device 1 includes connectors T3 and T4 at the output end. A light source 200 is connected between the connector T3 and the connector T4. A resistor 12 is provided between the connector T4 and the negative electrode of the capacitor 10. One end of the resistor 12 is connected to the control unit 13. The output of the control unit 13 is connected to the drive circuit 8.

  The lighting circuit 16 supplies power to the light source 200 by turning on and off the switching element 7. In the present embodiment, the lighting circuit 16 includes a step-down chopper circuit. By the on / off control of the switching element 7, the voltage supplied from the DC power supply 100 is stepped down by the inductor 9. The current flowing through the inductor 9 is smoothed by the capacitor 10 and flows to the light source 200. As a result, the light source 200 is turned on. The diode 11 provides a current path for the inductor 9 when the switching element 7 is turned off.

  The resistor 12 is provided in series with the light source 200. For this reason, a current flowing through the light source 200 flows through the resistor 12. The resistor 12 detects a voltage corresponding to the current flowing through the light source 200. The control unit 13 controls on / off of the switching element 7 according to the detection voltage of the resistor 12. The control unit 13 controls on / off of the switching element 7 so that the power supplied to the light source 200 is constant. In the lighting device 14 of the present embodiment, the control unit 13 controls the switching element 7 so that the voltage applied across the resistor 12 is constant. Thereby, the current flowing through the light source 200 is subjected to constant current control.

  The control unit 13 is a microcomputer, for example. The control unit 13 controls on / off of the switching element 7 via the drive circuit 8. The drive circuit 8 supplies a gate signal for controlling on / off of the switching element 7 to the gate of the switching element 7 in accordance with a signal from the control unit 13.

  In the first embodiment, the lighting circuit 16 includes the step-down chopper circuit. The lighting circuit 16 only needs to be a circuit that receives power supplied from the DC power supply 100 and lights the light source 200.

  FIG. 2 is a circuit block diagram of a lighting fixture 180 according to a comparative example of the first embodiment. The luminaire 180 includes a light source lighting device 101. The light source lighting device 101 does not include the flicker suppression circuit 2. The light source lighting device 101 includes a capacitive element 6 between the DC power supply 100 and the lighting device 14. The capacitive element 6 is connected in parallel with the DC power source 100.

  FIG. 3 is a diagram illustrating a current-voltage waveform when the lighting fixture 180 according to the comparative example of the first embodiment is turned on. With reference to FIG. 3, operation | movement of each part at the time of power activation of the lighting fixture 180 is demonstrated. Here, as shown in FIG. 2, the point A is the output on the high potential side of the DC power supply 100. Point B is an input on the high potential side of the lighting device 14. Iin is a current flowing from the DC power source 100 to the light source lighting device 101.

  In FIG. 3, the rise of the voltage at point A indicates the timing when the DC power supply 100 is turned on. As shown in FIG. 2, point B has the same potential as point A. For this reason, the voltage waveform at point B is the same as that at point A. When the power is turned on, the capacitive element 6 is not charged. For this reason, a current for charging the capacitive element 6 flows immediately after the power is turned on. For this reason, as shown in the current waveform of Iin, an excessive current flows from the DC power supply 100 in a short time immediately after the power is turned on. This is called inrush current. After the capacitive element 6 is charged, Iin becomes a value corresponding to the current flowing through the lighting device 14 during constant current control. For this reason, Iin is constant.

  If the inrush current of the light source lighting device 1 is large, there is a possibility that the number of lighting fixtures 180 connected to one breaker may be limited depending on the specifications of the breaker overcurrent protection. Further, when the DC power supply 100 is turned off / on with a wall switch, there is a possibility that the contact of the switch is welded due to an inrush current. For this reason, it may be necessary to suppress inrush current.

  FIG. 4 is a diagram illustrating a current-voltage waveform when the lighting fixture 80 according to Embodiment 1 is turned on. As shown in FIG. 1, point A is the output on the high potential side of the DC power supply 100. Point B is an input on the high potential side of the lighting device 14. Iin is a current flowing from the DC power source 100 to the light source lighting device 1. Further, the point C is on the high potential side of the capacitive element 6. A voltage waveform at the point C indicates a voltage applied to both ends of the capacitive element 6.

  Similar to the comparative example, the voltage rises at the timing when the DC power supply 100 is turned on at the point A. In the present embodiment, the point B is connected to the point A via the second diode 3. For this reason, when the power is turned on, the point B becomes a potential lower than the point A by the voltage drop of the second diode 3. Since the voltage drop of the second diode 3 is smaller than the potential at point A, the potentials at point A and point B are considered to be substantially the same. For this reason, when the DC power supply 100 is turned on, the voltage at the point A rises, and the voltage at the point B rises accordingly.

  In the present embodiment, the capacitive element 6 is charged via the impedance element 4 when the power is turned on. For this reason, the voltage applied to the capacitive element 6 rises according to the time constants of the capacitive element 6 and the impedance element 4. When the power is turned on, the step-down chopper circuit is not operating. For this reason, the current for charging the capacitive element 6 occupies most of Iin. Here, the current for charging the capacitive element 6 is limited by the impedance element 4. Therefore, in this embodiment, it is possible to suppress an excessive current from flowing in a short time as compared with the comparative example.

  The maximum value of the inrush current that flows when the power is turned on is substantially equal to the value obtained by dividing the power supply voltage of the DC power supply 100 by the resistance value of the impedance element 4. For this reason, in this Embodiment, the peak value of the rush current at the time of power activation is suppressed rather than a comparative example. The current for charging the capacitive element 6 decreases with time as the capacitive element 6 is charged. After the capacitive element 6 is charged, Iin becomes a value corresponding to the current flowing through the lighting device 14 during constant current control. For this reason, Iin is kept constant.

  FIG. 5 is a diagram illustrating a current-voltage waveform at the time of power supply fluctuation of the lighting fixture 180 according to the comparative example of the first embodiment. With reference to FIG. 5, operation | movement of each part when a power supply voltage is fluctuate | varied during steady operation in the lighting fixture 180 which concerns on a comparative example is demonstrated. As shown in FIG. 2, Iout is a current flowing through the light source 200. In a steady state, a stable DC voltage is supplied from the DC power source 100 to the lighting device 14. For this reason, a constant DC voltage is applied to the points A and B. Also, Iout is constant.

  Here, due to an abnormality in the DC power supply 100, the power supply voltage may be reduced or cut off for a short time. As shown in the voltage waveform at point A in FIG. 5, it is assumed that the power supply voltage of the DC power supply 100 has dropped during the steady operation of the lighting device 14. At this time, the voltage waveform at the point B is the same as that at the point A as in the case of FIG.

  In the lighting device 14, the detection voltage of the resistor 12 is fed back to the control unit 13. The control unit 13 controls the current flowing through the light source 200 to be constant according to the detection voltage. Here, when the voltage at point B, which is the voltage supplied to the lighting device 14, fluctuates, the response speed of the feedback of the lighting device 14 may not follow. At this time, the lighting device 14 may not be able to control the current flowing through the light source 200 to be constant. In this case, Iout decreases in synchronization with the voltage at point B. Since Iout is a current flowing through the light source 200, fluctuations in Iout cause flickering of light emitted from the light source 200.

  FIG. 6 is a diagram illustrating a current-voltage waveform when the power supply of the lighting fixture 80 according to Embodiment 1 is varied. In a steady state, a stable DC voltage is supplied from the DC power source 100 to the lighting device 14. For this reason, a constant DC voltage is applied to the points A and B. At this time, the lighting device 14 is in a steady operation. Here, the steady operation indicates a state in which the lighting device 14 supplies a constant power to the light source 200. At this time, Iout which is a current flowing through the light source 200 is constant.

  Next, it is assumed that the power supply voltage of the DC power supply 100 decreases during the steady operation of the lighting device 14 as shown in the voltage waveform at the point A in FIG. In the present embodiment, the second diode 3 is provided between the points A and B. The anode of the second diode 3 is connected to the DC power supply 100 side. The cathode of the second diode 3 is connected to the lighting device 14 side. For this reason, when the potential at the point B is higher than the potential at the point A, the second diode 3 prevents the current from flowing from the point B to the point A. For this reason, the B point maintains a higher potential than the A point.

  During the period when the potential at the point A is decreasing, the electric power stored in the capacitive element 6 is supplied from the point C to the point B via the first diode 5. At this time, the point B has a potential lower than the point C by the voltage drop of the first diode 5. Here, since the voltage drop of the first diode 5 is sufficiently smaller than the potential at the point B, the potential at the point B and the potential at the point C are substantially equal. The electric charge of the capacitive element 6 supplied to the point B is consumed for operating the lighting device 14. Further, during the period when the potential at the point A is lowered, no power is supplied from the DC power source 100 to the light source 200 side by the second diode 3. For this reason, the potential at the point C decreases with time. As the potential at point C decreases, the potential at point B also decreases.

  When the DC power supply 100 returns from the drop in the power supply voltage, the potential at the point A is restored. In this case, the operations at points B and C are different. When the potential at the point A is restored, a current flows through the second diode 3. For this reason, point B is immediately at the same potential as point A. On the other hand, since the capacitive element 6 is charged via the impedance element 4, the potential at the point C increases with time.

  Next, Iout will be described. The response speed of the feedback of the lighting device 14 may not be able to follow the fluctuation of the voltage at point B, which is the voltage supplied to the lighting device 14. At this time, Iout decreases in synchronization with the potential at point B. Here, in the light source lighting device 101 according to the comparative example, the voltage fluctuation at the point A is reflected in Iout. On the other hand, in the present embodiment, by providing the second diode 3, it is possible to suppress the voltage fluctuation at the point A from being reflected on Iout as shown in FIG.

  In the present embodiment, when the power supply voltage of the DC power supply 100 varies, the potential at the point B does not follow the point A. The potential at point B decreases as the charge stored in the capacitive element 6 decreases. For this reason, even when the response speed of the feedback of the lighting device 14 cannot follow the fluctuation of the power supply voltage, the fluctuation of Iout can be suppressed as compared with the comparative example 180. The fluctuation of Iout appears as flickering of light emitted from the light source 200. Therefore, flickering of the light source 200 can be suppressed in this embodiment.

  From the above, in the lighting fixture 80 according to the present embodiment, the flickering of the light source 200 and the inrush current can be suppressed with respect to power supply fluctuations. Further, in the flicker suppression circuit 2, a circuit that suppresses flicker and a circuit that suppresses inrush current are integrated. For this reason, it is not necessary to provide a circuit for suppressing inrush current separately from a circuit for suppressing flicker. Further, in the present embodiment, the inrush current and the flicker can be suppressed by the flicker suppression circuit 2 having a simple configuration. Therefore, in the present embodiment, the light source lighting device 1 can be downsized. Moreover, the light source lighting device 1 can be obtained at low cost.

  By providing the flicker suppression circuit 2 as described above, the flicker of the light source 200 can be suppressed even when the feedback of the lighting device 14 cannot follow the fluctuation of the power source. The second diode 3 can prevent the electric charge stored in the capacitive element 6 from flowing to the DC power supply 100 side. Here, when the configuration for preventing the current from flowing from the light source lighting device 1 is provided on the DC power supply 100 side, the flicker suppression circuit 2 may not include the second diode 3. In this case, the configuration of the flicker suppression circuit 2 can be further simplified.

  Further, for example, as the capacitance of the capacitive element 6 is increased, the fluctuation of the voltage at the point C due to the consumption of the charge of the capacitive element 6 can be suppressed. For this reason, by increasing the capacitance of the capacitive element 6, it is possible to further suppress fluctuations in Iout when the power supply fluctuates. Therefore, by increasing the capacitance of the capacitive element 6, it is possible to make it difficult for the user to recognize flicker when the power supply voltage varies.

  On the other hand, the larger the capacitance of the capacitive element 6, the longer the time until the capacitive element 6 is charged. For this reason, the time from when the power is turned on until the flicker suppression circuit 2 can operate becomes longer. That is, the time until the lighting fixture 80 can stand by becomes longer.

  For this reason, the capacitance of the capacitive element 6 may be adjusted in consideration of how long the flicker is suppressed when the power supply voltage is reduced or cut off. Further, the capacitance of the capacitive element 6 may be selected in consideration of the power consumed by the lighting device 14 and the light source 200. Moreover, it is good also as what operates the illuminating device in which the flicker suppression circuit 2 was actually mounted, and selects the capacitive element 6 of appropriate electrostatic capacitance.

  Next, an example of a method for selecting the resistance value of the impedance element 4 will be described. Generally, the number of lighting devices such as the light source lighting device 1 or the lighting fixture 80 that can be connected to one breaker is determined in consideration of the rated current of the breaker and the overcurrent characteristics of the lighting device.

  For example, the number of lighting devices that can be connected to the breaker is calculated so that the total value of the rated currents of a plurality of lighting devices connected to the breaker is smaller than the rated current of the breaker. Next, the number of lighting devices that can be connected to the breaker is calculated so that the total value of the overcurrent values of a plurality of lighting devices connected to the breaker is smaller than the rated current of the breaker. The smaller of the number of connected devices calculated from the rated current of the lighting device and the number of connected devices calculated from the overcurrent value of the lighting device is the number of lighting devices that can be connected to one breaker.

  Therefore, the smaller the rated current and overcurrent value of the lighting device, the more lighting devices that can be connected to one breaker. Here, since the rated current is determined by the specifications of the lighting device, adjustment is difficult. On the other hand, in this Embodiment, an overcurrent can be suppressed by suppressing an inrush current with the flicker suppression circuit 2. FIG. For this reason, by controlling the inrush current so that the number of light source lighting devices 1 that can be connected to one breaker is determined by the rated current of the light source lighting device 1, a plurality of light source lighting devices 1 are efficiently connected to the breaker. it can.

  Breaker breaking characteristics vary from product to product. That is, the overcurrent value for breaking the breaker and the period during which the overcurrent for breaking the breaker is different for each product. However, in many products, the breaker is often not cut off even if a current of 200% of the rated current of the breaker flows for a few seconds. For this reason, in this Embodiment, the rush current value of the light source lighting device 1 connected to a breaker is suppressed within 200% of the rated current of the light source lighting device 1. By making the inrush current value of the light source lighting device 1 less than twice the rated current of the light source lighting device 1, the number of light source lighting devices 1 that can be connected to one breaker is not the inrush current value but the rated current. It can be determined by the value.

  The peak value of the inrush current is substantially equal to the value obtained by dividing the power supply voltage by the resistance value of the impedance element 4. For this reason, in the present embodiment, the resistance value of the impedance element 4 is set to be equal to or greater than the value obtained by dividing the power supply voltage of the DC power supply 100 by a value twice the rated current value input from the DC power supply 100. Thereby, the peak value of the inrush current can be suppressed to 2 times or less of the rated current of the light source lighting device 1.

  From the above, the number of connected light source lighting devices 1 to the breaker can be determined from the rated current by eliminating the restriction due to the inrush current. Therefore, many light source lighting devices 1 and lighting fixtures 80 can be connected to the breaker. Thereby, a breaker can be used efficiently.

  For example, it is assumed that the power supply voltage of the DC power supply 100 is DC400V in a steady state. Further, it is assumed that the input power from the DC power supply 100 is 100 W and the input current is 0.4 A. That is, the rated current of the light source lighting device 1 is 0.4A. At this time, the inrush current is preferably suppressed to 0.8 A or less. Since DC400 ÷ 0.8A = 500Ω, the resistance value of the impedance element 4 is preferably selected to be 500Ω or more.

  Next, another method for selecting the resistance value of the impedance element 4 will be described. The larger the resistance value of the impedance element 4 is, the longer the time until the capacitive element 6 is charged. That is, the time until the flicker suppression circuit 2 becomes operable becomes longer. It is desirable that the flicker suppression circuit 2 be in an operable state before the light source 200 is turned on after the power is turned on. The time from when the light source lighting device 1 is turned on until the light source 200 is turned on differs depending on the product, but is generally designed to be within one second.

  In the series circuit 20, the capacitive element 6 is charged to 63.2% in the time calculated from the time constant τ = CR. Here, C is the capacitance of the capacitive element 6, and R is the resistance value of the impedance element 4. It takes 3 times the time constant τ to charge the capacitive element 6 by 95% or more. If a margin is set for 1 second, which is the time from power-on to lighting, and the capacitive element 6 can be charged 95% or more within 900 ms, the flicker suppression circuit 2 is stably operated until the light source 200 is turned on. be able to. Therefore, the time constant τ may be equal to or less than one third of 900 ms.

  That is, the time constant τ between the impedance element 4 and the capacitive element 6 may be 300 ms or less. In the present embodiment, the upper limit value of the resistance value R of the impedance element 4 is set so that the time constant τ is 300 ms or less. Here, the capacitance of the capacitive element 6 is 47 μF. From τ = CR, 300 ms ÷ 47 μF = 6382Ω. Therefore, the resistance value R of the impedance element 4 may be 6382Ω or less.

80 lighting equipment, 100 DC power supply, 200 light source, 1 light source lighting device, 2 flicker suppression circuit, 3rd diode, 4 impedance element, 5 1st diode, 6 capacitive element, 7 switching element, 13 control unit, 14 lighting Device, 16 lighting circuit, 20 series circuit

Claims (8)

A lighting circuit that turns on the light source by receiving power from a DC power supply;
A flicker suppression circuit connected in parallel with the DC power source between the DC power source and the lighting circuit,
With
The flicker suppression circuit is
A capacitive element;
An impedance element connected in series with the capacitive element on the high potential side of the capacitive element;
A first diode having an anode connected to a connection point between the impedance element and the capacitive element, and a cathode connected to a high potential side of the lighting circuit;
A light source lighting device comprising: The flicker suppression circuit is
2. The light source lighting device according to claim 1, further comprising: a second diode having an anode connected to an output on a high potential side of the DC power source and a cathode connected to a high potential side of the impedance element.   3. The light source according to claim 1, wherein a resistance value of the impedance element is equal to or greater than a value obtained by dividing a power supply voltage of the DC power supply by a value that is twice the rated current input from the DC power supply. Lighting device.   The light source lighting device according to any one of claims 1 to 3, wherein a time constant between the impedance element and the capacitive element is 300 ms or less.   The light source lighting device according to claim 1, wherein the impedance element is a resistor.   The light source lighting device according to claim 1, wherein the capacitive element is a capacitor. A lighting device comprising the lighting circuit and a control unit;
The lighting circuit supplies power to the light source by turning on and off a switching element,
The light source lighting device according to claim 1, wherein the control unit controls on / off of the switching element to control power supplied to the light source to be constant. The light source lighting device according to any one of claims 1 to 7,
The light source;
A lighting apparatus comprising:

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