JP2011204554A - Discharge lamp lighting device and lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device, along with an illumination device, capable of suppressing an unnecessary lamp current when a lamp ambient temperature becomes high and a lamp impedance becomes small, thereby extending a lamp life, and moreover capable of reducing a stress to components.SOLUTION: The discharge lamp lighting device 10 and the illumination device include a DC power supply E, an inverter circuit 11 having switching elements Q1, Q2, a resonance circuit 12 composed of an inductor T1 and a capacitor C1. a discharge lamp La to which a resonance voltage is impressed, a detecting circuit 16 for detecting a resonance current or a resonance voltage, a feedback controlling circuit 15 for changing an operation frequency of the inverter circuit 11 so that the power to be supplied to the discharge lamp La may become almost constant against a target output in accordance with the detected value of the detecting circuit 16, an oscillation frequency controlling means 14 for switching over an oscillation frequency of the inverter circuit 11, a temperature detection unit 13 for detecting an ambient temperature, and a means for raising a minimum operation frequency in accordance with the ambient temperature.

Description

  The present invention relates to a discharge lamp lighting device for lighting a discharge lamp and a lighting device equipped with the discharge lamp lighting device.

  2. Description of the Related Art Conventionally, a discharge lamp lighting device and a lighting device that perform constant voltage control when a discharge lamp is lit are known (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2000-12266 (FIG. 1, paragraph numbers 0011 and 0012)

  As shown in FIG. 8, in the discharge lamp lighting device 100 of Patent Document 1, a series circuit of switching elements Q2 and Q3 made of MOSFETs is connected to a DC power source E via a resistor R6. A power supply side terminal of the preheating electrode F1 of the discharge lamp La is connected to a connection point between the DC power supply E and the switching element Q2. A starting capacitor C6 for resonance (and for supplying a preheating current) is connected in parallel between the non-power supply side terminals of the preheating electrodes F1 and F2 of the discharge lamp La. A ballast choke T1, which is an inductance element for resonance (and for current limiting), is provided between a connection point between the power supply side terminal of the preheating electrode F2 of the discharge lamp La and the switching elements Q2, Q3 via a coupling capacitor C5 for cutting DC. Is connected.

  The switching elements Q2 and Q3 are made of MOSFETs and are alternately turned on / off by a drive signal from a control circuit IC2 made of an integrated circuit. In the control circuit IC2, the first pin is a control power supply voltage input terminal, the second and fourth pins are drive signal voltage output terminals, the third pin is a reference voltage output terminal, the fifth pin is an abnormality detection input terminal, and the sixth pin Is a current output terminal for outputting a current for determining the oscillation frequency, Pin 7 is a current input / output terminal for charging / discharging a capacitor for determining the oscillation frequency, and Pin 8 (not shown) is a ground terminal.

  A capacitor C9 is connected to both ends of a resistor R6 connected in series with the switching element Q3 via a resistor R11 and a diode D6, and the terminal voltage of the capacitor C9 is input to the fifth pin of the control circuit IC2. The resistors R6 and R11, the diode D6, and the capacitor C9 constitute an abnormality detection circuit 101. The abnormality detection circuit 101 is a circuit that detects an abnormality of the discharge lamp La.

  The operating power source of the control circuit IC2 is a DC voltage obtained by making the voltage charged in the capacitor C3 from the DC power source E through the resistor R1 into a constant voltage by the Zener diode DZ. This DC voltage is divided by the resistors R9 and R10 of the error amplifier 102 and applied to the non-inverting input terminal of the operational amplifier IC3. A capacitor C2 is connected between the inverting input terminal and the output terminal of the operational amplifier IC3. A voltage obtained by averaging the high-frequency voltage generated in the resistor R6 connected in series with the switching element Q3 by the integrating circuit 103 including the resistor R5 and the capacitor C8 is applied to the inverting input terminal of the operational amplifier IC3. The output terminal of the operational amplifier IC3 is connected to the cathode of the diode D5, and the anode of the diode D5 is connected to the connection point between the resistor R2 and the 6th pin of the control circuit IC2 via the resistor R3. The resistor R2 connected to the 6th pin of the control circuit IC2 and the other end of the capacitor C4 connected to the 7th pin are grounded, and the oscillation frequency of the control circuit IC2 is determined by these time constants.

  Next, the configuration of the Emires detection circuit 104 will be described. The Emires detection circuit 104 including the error amplifier 102 and the integration circuit 103 is a circuit that detects the Emires lighting of the discharge lamp La and outputs a voltage for controlling the oscillation frequency, and generates a high frequency current flowing through the discharge lamp La. Detected by the detection resistor R6, the high frequency voltage detected by the detection resistor R6 is averaged by the integration circuit 103 composed of the resistor R5 and the capacitor C8, and the output voltage of the integration circuit 103 is connected to the resistors R9 and R10 of the error amplifier 102. The current flowing into the resistor R3 is controlled by changing the output voltage of the operational amplifier IC3 so that the reference voltage obtained at the point becomes equal.

  When the DC power supply E is turned on in the inverter circuit 105, a current flows in a closed loop of the DC power supply E → starting resistor R1 → control power supply capacitor C3 → DC power supply E, and the control power supply capacitor C3 is charged. The voltage of the control power supply capacitor C3 is applied to the first pin of the control circuit IC2. When the voltage of the control power supply capacitor C3 rises and reaches the operating voltage of the control circuit IC2, the control circuit IC2 starts oscillating. Due to this oscillation, a voltage is alternately applied at a high frequency from the second pin of the control circuit IC2 to the gate of the switching element Q2, and from the fourth pin to the gate of the switching element Q3, and the switching elements Q2 and Q3 are alternately turned on and off. The inverter circuit 105 oscillates at a high frequency.

  As a result, when the switching element Q3 is on, the inverter circuit 105 causes the DC power source E → preheating electrode F1 → starting capacitor C6 → preheating electrode F2 → coupling capacitor C5 → ballast choke T1 → switching element Q3 → detection resistor R6 → When the switching element Q2 is on in the closed loop of the DC power source E, the current flows in the closed loop of the coupling capacitor C5 → preheating electrode F2 → starting capacitor C6 → preheating electrode F1 → switching element Q2 → ballast choke T1 → coupling capacitor C5. The high frequency current flows through the series circuit of the ballast choke T1, the coupling capacitor C5, the preheating electrode F2, the starting capacitor C6, and the preheating electrode F1 alternately.

  At this time, there is a relationship of (capacitance of the coupling capacitor C5) >> (capacitance of the starting capacitor C6), and a resonant high voltage is generated in the starting capacitor C6 due to LC series resonance of the ballast choke T1 and the starting capacitor C6. Is applied to the discharge lamp La, and the discharge lamp La lights up.

  In the high frequency voltage waveform generated in the resistor R6 when the discharge lamp La is normally lit as shown in FIG. 9A, and the high frequency voltage waveform generated in the resistor R6 when the discharge lamp La is not lit as shown in FIG. When La is connected, a high-frequency voltage is generated in the detection resistor R6 of the abnormality detection circuit 101, but the voltage of the smoothing capacitor C9 is the peak value V1 of this high-frequency voltage due to the rectification action of the rectifier diode D6. Therefore, since the relationship with the operating voltage V5 of the abnormality detection input terminal (5th pin) of the control circuit IC2 to which the peak value VI is applied is set to satisfy V1 <V5, the oscillation of the control circuit IC2 Is continuing.

  On the other hand, the high-frequency voltage generated in the detection resistor R6 is averaged by the integration circuit 103 of the Emiles detection circuit 104, and this DC voltage is input to the inverting input terminal of the operational amplifier IC3 of the error amplifier 102. By the way, the oscillation frequency of the control circuit IC2 is determined by the capacitance value of the capacitor C4 and the current value flowing out from the current output terminal (6th pin) of the control circuit IC2 to the main oscillation resistors R2 and R3. The oscillation frequency is high. The current flowing from the current output terminal (No. 6 pin) to the resistor R3 changes according to the change in the output voltage of the operational amplifier IC3, thereby controlling the oscillation frequency of the control circuit IC2. Therefore, the control of the oscillation frequency of the control circuit IC2 is performed by controlling the output voltage of the operational amplifier IC3 so that the output voltage of the integrating circuit 12 becomes equal to the reference voltage of the non-inverting input terminal of the operational amplifier IC3. As a result, the average value of the high-frequency current flowing through the detection resistor R6, that is, the sum of the power consumed by the preheating electrodes F1 and F2 of the discharge lamp La is kept constant. In this way, the Emires detection circuit 104 controls the oscillation frequency of the control circuit IC2 so that the high-frequency average current flowing through the detection resistor R6 is held at the value set by the Emiless detection circuit 104.

  Next, the operation when the discharge lamp La is not lit due to the end of life or failure of the discharge lamp La will be described. Even when a high frequency current flows through the series circuit of the ballast choke T1, the coupling capacitor C5, the preheating electrode F1, the starting capacitor C6, and the preheating electrode F2, the discharge lamp La is in a state of consuming abnormal power at the end of its life. The oscillation frequency of the control circuit IC2 is controlled so that the Emires detection circuit 104 operates and the high-frequency average current flowing through the detection resistor R6 is held at the set value.

However, when the discharge lamp La is at the end of its life or defective, there is a relationship of (capacitance of the coupling capacitor C5) >> (capacitance of the starting capacitor C6). Resonant high voltage is generated in this, and this resonant high voltage is applied to the discharge lamp La, but the discharge lamp La is not lit.
At this time, a high-frequency voltage is generated in the detection resistor R6 of the abnormality detection circuit 101, but the voltage of the smoothing capacitor C9 is almost at the peak value V3 of this high-frequency voltage due to the rectifying action of the rectifier diode D6, and the peak value V3 is Since the relationship between the applied voltage V5 of the abnormality detection input terminal (5th pin) of the applied integrated circuit IC2 is set to satisfy V3> V5, the oscillation of the control circuit IC2 is stopped. The oscillation stop state is held by the current supplied from the DC power source E via the starting resistor R1.

  Next, when the discharge lamp La is at the end of its life and the discharge lamp La is in an emiless lighting state in which the power is excessively consumed, the discharge lamp La is in a state in which the electron emitting material applied to the preheating electrodes F1 and F2 is consumed. Since the lamp is lit in the Emires state (electron emission failure state), the voltage of the discharge lamp La increases. However, the error amplifier 102 causes the output voltage of the operational amplifier IC3 to be higher than when the discharge lamp La is normally lit. As a result, the oscillation frequency of the control circuit IC2 becomes high, and the sum of the power consumed by the discharge lamp La is kept constant as in the case of normal lighting.

  Thus, in the discharge lamp lighting device 100, the voltage of the detection resistor R6 connected in series with the switching element Q3 is detected and feedback control is performed by the operational amplifier IC3, and the power is consumed both when the normal discharge lamp is lit and when the end-of-life discharge lamp is lit. At the same time as controlling to be constant, when the discharge lamp La becomes abnormal and does not light up, the oscillation is stopped by utilizing the high voltage of the detection resistor R6. Safety can be increased.

  However, the discharge lamp lighting device 100 of the above-mentioned Patent Document 1 is used during normal lighting in addition to considering a state where the lamp voltage is high at the end of the life, that is, a state where the lamp impedance is increased, when performing constant power control. The ambient temperature characteristics of the discharge lamp must be considered. That is, the impedance of the discharge lamp La is temperature-dependent, and the lamp impedance changes depending on the coldest spot temperature in a general fluorescent lamp mercury lamp and the temperature of the amalgam enclosed in an amalgam-containing lamp.

  As shown in FIG. 10, the lamp impedance decreases as the ambient temperature increases at room temperature or higher in single lamp lighting. In other words, when the lamp is used in an appliance, the lamp impedance changes depending on the appliance shape and the lamp installation direction. Therefore, when the constant power control is performed near the rated lamp power of the discharge lamp La using the constant power control as in the discharge lamp lighting device 100 of the above-mentioned Patent Document 1, an appliance for installing the lamp at the normal temperature in the state of including the appliance. For example, the lamp impedance is completely different between the structure in which the discharge lamp is covered with an instrument and the structure in which the discharge lamp is exposed. That is, even in the same discharge lamp, the ambient temperature of the discharge lamp is higher in the illumination device having a structure covering the discharge lamp and the illumination device having a structure in which the discharge lamp is exposed. Therefore, the lamp impedance is also different, and the lamp impedance is smaller in the illumination device that covers the discharge lamp than the illumination device with the bare structure, so that the current exceeding the rated lamp current of the discharge lamp flows to the discharge lamp, and the discharge lamp It will result in a short life.

  As shown in FIG. 11, when the discharge lamp La is at a high temperature, the lamp impedance is lowered and the frequency is changed to fch, whereby the current is increased. As a result, a current greater than the rated lamp current flows through the discharge lamp La, so that stress on the components increases.

  The present invention has been made to solve the above-described problems, and its purpose is to extend the life of the lamp by suppressing useless lamp current when the lamp ambient temperature becomes high and the lamp impedance becomes small. It is another object of the present invention to provide a discharge lamp lighting device and a lighting device that can reduce stress on components.

  A discharge lamp lighting device according to the present invention includes a DC power supply, an inverter circuit having a switching element for switching the output of the DC power supply at a high frequency, a resonance circuit including an inductor and a capacitor to which the high frequency output of the inverter circuit is applied, A discharge lamp to which a resonance voltage of the circuit is applied, a detection circuit for detecting a resonance current or a resonance voltage of the resonance circuit, and an electric power supplied to the discharge lamp according to a detection value of the detection circuit are substantially constant with respect to a target output. Accordingly, a feedback control circuit that varies the operating frequency of the inverter circuit, an oscillation frequency control unit that switches the oscillation frequency of the inverter circuit, a temperature detection unit that detects the ambient temperature, and a unit that increases the minimum operating frequency according to the ambient temperature are provided. .

  The discharge lamp lighting device according to the present invention includes means for increasing the minimum operating frequency when the ambient temperature becomes equal to or higher than a certain temperature by the temperature detector.

  In the discharge lamp lighting device according to the present invention, the temperature detection unit is disposed close to the switching element of the inverter circuit unit or the inductor of the resonance circuit.

  An illumination device according to the present invention includes a main body on which a discharge lamp lighting device is mounted, and a discharge lamp to which electric power is supplied from the discharge lamp lighting device.

  According to the discharge lamp lighting device and the lighting device of the present invention, when the lamp ambient temperature becomes high and the lamp impedance becomes small, it is possible to suppress the useless lamp current and extend the lamp life and There is an effect that stress can be reduced.

The external appearance perspective view seen from diagonally downward of the illuminating device equipped with the discharge lamp lighting device of 1st Embodiment which concerns on this invention. Circuit diagram of the discharge lamp lighting device of FIG. Detailed circuit configuration diagram of the discharge lamp lighting device of FIG. Operating frequency graph when ambient temperature is high in the discharge lamp lighting device of FIG. The circuit block diagram of the discharge lamp lighting device of 2nd Embodiment which concerns on this invention The top view of the circuit board in the illuminating device equipped with the discharge lamp lighting device of 3rd Embodiment concerning this invention. The bottom view of the circuit board in the illuminating device equipped with the discharge lamp lighting device of 4th Embodiment concerning this invention. Circuit diagram of a conventional discharge lamp lighting device (A) is a high-frequency voltage waveform diagram during normal lighting, and (B) is a high-frequency voltage waveform diagram during non-lighting. Lamp impedance graph when ambient temperature rises Operating frequency graph when ambient temperature is high

  Hereinafter, a discharge lamp lighting device and a lighting device according to a plurality of embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
As shown in FIG. 1, the lighting device 1 according to the first embodiment of the present invention has a main body 2 equipped with a discharge lamp lighting device 10, and the discharge lamp La is attached to two pairs of sockets 3 included in the main body 2. ing.
As shown in FIGS. 2 and 3, the discharge lamp lighting device 10 according to the first embodiment of the present invention includes a DC power source E, an inverter circuit 11 that converts the DC power source E into a high-frequency voltage, a ballast choke T1, and a capacitor. A resonance circuit 12 composed of C1, a discharge lamp La connected in parallel with the capacitor C1, a temperature detection unit 13 for detecting the ambient temperature and changing the operating frequency of the oscillation frequency control circuit 14 according to the temperature, preheating, starting, lighting , And an oscillation frequency control circuit 14 that is applied to the inverter circuit 11, a feedback circuit 15, an integrated circuit IC, and a detection circuit 16 that includes a resistor R1.

  The inverter circuit 11 includes a switching element Q1 that is an N-channel FET, a switching element Q2 that is also an N-channel FET, and a detection resistor R1 that constitutes the detection circuit 16. The detection resistor R1 detects a current flowing through the switching element Q1 and converts the voltage. In the inverter circuit 11, the output terminal of the DC power source E is connected to the drain terminal of the switching element Q1, and the source terminal of the switching element Q1 is connected to the drain terminal of the switching element Q2. The source terminal of the switching element Q2 is connected to the detection resistor R1 of the detection circuit 16, and the detection resistor R1 is connected to the circuit ground. The gate terminal of the switching element Q1 and the gate terminal of the switching element Q2 are connected to the oscillation frequency control circuit 14, and the output terminal 17 of the inverter circuit 11 is connected to the ballast choke T1 of the resonance circuit 12.

The oscillation frequency control circuit 14 includes resistors R2, R3, R4, R5, and R6, a variable resistor R7, and capacitors C2, C3, and C4, and includes a positive temperature coefficient thermistor PTH1 that constitutes the temperature detection unit 13. . The positive temperature coefficient thermistor PTH1 is connected to the port Rosc of the integrated circuit IC.
The feedback circuit 15 includes an operational amplifier OP1, a diode D1 connected to the output terminal of the operational amplifier OP1, resistors R8 and R9, and a capacitor C5.
The detection circuit 16 is connected to the negative terminal of the operational amplifier OP1 through the resistor R10.

  The oscillation frequency control circuit 14 switches the switch in the integrated circuit IC after a time set by the resistance value and the capacitance value by the resistors R2 and R3 connected to the port Rpre and the port Rstr of the integrated circuit IC after the power is turned on. Is switched. Thus, the oscillation frequency control circuit 14 drives the inverter circuit 11 while changing the frequency stepwise from the preheating mode (frequency fa) to the start mode (frequency fb) to the lighting mode (frequency fc).

  The feedback circuit 15 converts the resonance current generated by the resonance circuit 12 into a voltage by the detection resistor R1, and this voltage is applied to the negative terminal of the operational amplifier OP1 through the resistor R10. Then, the operational amplifier OP1 compares the voltage appearing at the − terminal and the reference voltage applied to the + terminal to vary the operating frequency of the inverter circuit 11 so that both voltages are substantially equal. Here, the voltage appearing at the negative terminal of the operational amplifier OP1 changes in inverse proportion to the power consumption of the resonance circuit 12. And most of the power consumption of the resonance circuit 12 is occupied by the output voltage of the resonance circuit 12. That is, the feedback circuit 15 varies the operating frequency of the inverter circuit 11, that is, performs constant voltage control so that the output voltage of the discharge lamp La slides substantially constant.

Further, the feedback circuit 15 does not operate in the preheating and starting modes, and in the lighting mode, the output voltage of the discharge lamp La is made substantially constant between fc and fmin by the lamp impedance depending on the type of the discharge lamp or the ambient temperature. Thus, the operation of changing the operating frequency of the inverter circuit 11 is performed.
Since the temperature detection unit 13 is connected to the port Rosc of the integrated circuit IC because the positive characteristic thermistor PTH1 is connected to the temperature detection unit 13, the minimum operating frequency fmin is set by the resistance value of the resistor R4 connected to the port Rosc. It is determined by the capacity of R4 + positive characteristic thermistor PTH1.
In addition, as the temperature detection part 13, it may replace with positive characteristic thermistor PTH1, and may detect the temperature of negative characteristic thermistors, etc., and may use various elements from which resistance changes.

  As shown in FIG. 4, the discharge lamp lighting device 10 can gradually increase the minimum operating frequency fmin at a high temperature as the temperature is increased by the temperature detector 13, whereby the frequency fch is clamped at the frequency fmin. As a result, current can be suppressed at a high temperature, and excessive stress on the components can be reduced.

Therefore, in the discharge lamp lighting device 10 of the first embodiment, the ambient temperature is detected by the temperature detector 13 and the minimum operating frequency is increased by the ambient temperature.
Thereby, in the discharge lamp lighting device 10 of the first embodiment, when the lamp ambient temperature becomes high and the lamp impedance becomes small, the minimum operating frequency fmin is gradually increased as the temperature becomes high, and the frequency fch is increased. By clamping at fmin, it is possible to suppress the useless lamp current at a high temperature and extend the lamp life. In addition, in the discharge lamp lighting device 10 of the first embodiment, excessive stress on the components can be reduced.

  Further, in the illumination device 1 of the first embodiment, since the current can be suppressed by the discharge lamp lighting device 10 at a high temperature, long life illumination is achieved by reducing excessive stress on the discharge lamp La. A device 1 can be provided.

(Second Embodiment)
Next, a discharge lamp lighting device according to a second embodiment of the present invention will be described. In the following embodiments, components that are the same as those in the first embodiment described above or functionally similar components are simplified or omitted by giving the same reference numerals or equivalent symbols in the drawings. To do.

  As shown in FIG. 5, the discharge lamp lighting device 30 according to the second embodiment of the present invention includes a temperature detection unit 13 including a switching element Q3 that is an NPN transistor and resistors R11, R12, and R13. The switching element Q3 has a base terminal connected to the intersection of the resistors R11 and R12, a collector terminal connected to the port Rosc of the integrated circuit IC, and an emitter terminal connected to the intersection of the resistors R13 and R4. As the switching element Q3, switching such as a MOSFET may be applied instead of the NPN transistor.

  In the discharge lamp lighting device 30, when the ambient temperature detected by the temperature detector 13 exceeds a certain temperature, the switching element Q3 is turned on, and the current of the port Rosc of the integrated circuit IC is reduced, so that the minimum operation Increase the frequency fmin.

  Therefore, in the discharge lamp lighting device 30 of the second embodiment, when the ambient temperature exceeds a certain temperature, the minimum operating frequency fmin is increased, thereby suppressing the current at a high temperature and causing excessive stress on the components. Can be reduced.

(Third embodiment)
Next, a discharge lamp lighting device according to a third embodiment of the present invention will be described.
As shown in FIG. 6, the discharge lamp lighting device 40 according to the third embodiment of the present invention has a ballast choke T <b> 1 of the resonance circuit 12 near the end of the upper surface of the circuit board 4 housed in the main body 2 of the lighting device 1. Is disposed, and a positive temperature coefficient thermistor PTH1 is attached in the vicinity of the ballast choke T1.

  Therefore, in the discharge lamp lighting device 40 of the third embodiment, the ballast choke T1 that generates excessive stress can be protected.

(Fourth embodiment)
Next, a discharge lamp lighting device according to a fourth embodiment of the present invention will be described.
As shown in FIG. 7, the discharge lamp lighting device 50 according to the fourth embodiment of the present invention includes an integrated circuit IC, a switching element Q1, and a switching element Q1 at the center of the lower surface of the circuit board 4 housed in the main body 2 of the lighting device 1. A switching element Q2 is arranged, and a positive temperature coefficient thermistor PTH1 is attached in the vicinity of the switching element Q1 and the switching element Q2.

  Therefore, in the discharge lamp lighting device 50 of the fourth embodiment, the switching elements Q1 and Q2 that generate excessive stress can be protected.

  In addition, the electronic components etc. which comprise the inverter circuit 11 and the resonance circuit 12 which were used in each embodiment are not limited to what was illustrated, and can be changed suitably.

DESCRIPTION OF SYMBOLS 1 Illuminating device 2 Main body 10, 30, 40, 50 Discharge lamp lighting device 11 Inverter circuit 12 Resonant circuit 13 Temperature detection part 14 Oscillation frequency control circuit (oscillation frequency control means)
15 Feedback circuit (feedback control circuit)
16 Detection circuit E DC power supply La Discharge lamp Q1, Q2 Switching element T1 Ballast choke (inductor)

Claims (4)

DC power supply,
An inverter circuit having a switching element for switching the output of the DC power supply at a high frequency;
A resonant circuit composed of an inductor and a capacitor to which the high-frequency output of the inverter circuit is applied;
A discharge lamp to which a resonance voltage of the resonance circuit is applied;
A detection circuit for detecting a resonance current or a resonance voltage of the resonance circuit;
A feedback control circuit that varies the operating frequency of the inverter circuit so that the power supplied to the discharge lamp is substantially constant with respect to a target output in accordance with the detection value of the detection circuit;
Oscillation frequency control means for switching the oscillation frequency of the inverter circuit;
A temperature detector for detecting the ambient temperature;
A discharge lamp lighting device comprising: means for increasing a minimum operating frequency according to the ambient temperature. In the discharge lamp lighting device according to claim 1,
A discharge lamp lighting device comprising means for increasing a minimum operating frequency when the ambient temperature becomes equal to or higher than a certain temperature by the temperature detector. In the discharge lamp lighting device according to claim 1 or 2,
A discharge lamp lighting device in which the temperature detection unit is disposed close to a switching element of the inverter circuit unit or an inductor of the resonance circuit. The discharge lamp lighting device according to any one of claims 1 to 3,
A main body on which the discharge lamp lighting device is mounted,
A lighting device comprising: a discharge lamp to which electric power is supplied from the discharge lamp lighting device.

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