A flyback boost converter circuit and a light source driving circuit

Abstract

This invention relates to a flyback boost converter circuit and a light source driving circuit. In the flyback boost converter circuit, a control module outputs a first control signal to a second switching module. The second switching module converts the first control signal into a second control signal, causing a voltage conversion module to sequentially boost and rectify the DC power supply according to the second control signal. The processed energy is then stored in a first energy storage module, which stores the energy and outputs a first high-voltage signal at its first terminal. Therefore, this flyback boost converter circuit can boost the DC power supply to obtain a higher high-voltage signal.

Description

Technical Field

[0001] This invention relates to the field of flyback circuits, and in particular to a flyback boost converter circuit and a light source driving circuit. Background Technology

[0002] Due to the low luminous flux and short lifespan of halogen tungsten filament lamps, most car and truck headlights on the market use automotive metal halide lamps. Automotive metal halide lamps are high-pressure gas discharge lamps filled with a mixture of xenon inert gas; they do not have a halogen filament and are simply called light sources, and can also be referred to as metal halide lamps or xenon lamps.

[0003] Currently, the voltage of automotive on-board power supplies is too low to drive the light source. It is necessary to upgrade the automotive on-board power supply to a higher voltage signal to meet the operating voltage and current required by the light source. Summary of the Invention

[0004] The present invention aims to provide a flyback boost converter circuit and a light source driving circuit, which can realize boost conversion to output a higher voltage signal.

[0005] To address the aforementioned technical problems, the embodiments of the present invention provide the following technical solutions:

[0006] In a first aspect, embodiments of the present invention provide a flyback boost converter circuit, the flyback boost converter circuit including a control module, a second switching module, a voltage conversion module and a first energy storage module;

[0007] The first terminal of the second switch module is used to connect to the first power supply voltage, the second terminal of the second switch module is connected to the first terminal of the control module, and the third terminal of the second switch module is connected to the first terminal of the voltage conversion module.

[0008] The second terminal of the voltage conversion module is connected to a DC power supply, and the third terminal of the voltage conversion module is connected to the first terminal of the first energy storage module.

[0009] The control module is used to output a first control signal to the second switch module;

[0010] The second switch module is used to convert the first control signal to obtain a second control signal;

[0011] The voltage conversion module is used to sequentially boost and rectify the DC power supply according to the second control signal, and store the processed energy in the first energy storage module.

[0012] The first energy storage module stores the energy to output a first high-voltage signal at the first end of the first energy storage module.

[0013] Secondly, embodiments of the present invention provide a light source driving circuit, the light source driving circuit including: the flyback boost converter circuit as described above.

[0014] In some embodiments, the light source driving circuit further includes a trigger circuit;

[0015] The third terminal of the voltage conversion module is connected to the second terminal of the trigger circuit and the third terminal of the trigger circuit, respectively, and the third terminal of the control module is connected to the first terminal of the trigger circuit.

[0016] The sixth terminal of the control module is connected to the first or second terminal of the light source, and the control module is also used to detect the current of the light source;

[0017] The fourth terminal of the trigger circuit is connected to the second terminal of the light source, and the first terminal of the light source is grounded. When the current of the light source is less than or equal to a first preset value, the flyback boost converter circuit is also used to output a first driving signal to the trigger circuit. The trigger circuit is used to convert the first high-voltage signal into a second high-voltage signal according to the first driving signal to ignite the light source.

[0018] In some embodiments, the light source driving circuit further includes a direction adjustment circuit;

[0019] The first terminal of the direction adjustment circuit is connected to the third terminal of the voltage conversion module, the second terminal of the direction adjustment circuit is connected to the fourth terminal of the control module, the third terminal of the direction adjustment circuit is connected to the third terminal of the trigger circuit, the fourth terminal of the direction adjustment circuit is connected to the first terminal of the light source, the second terminal of the light source is connected to the fourth terminal of the trigger circuit, and the fifth terminal of the direction adjustment circuit is grounded. When the current of the light source is greater than or equal to a second preset value, the flyback boost converter circuit is further used to stop outputting the first driving signal to the trigger circuit and output a second driving signal to the direction adjustment circuit. The direction adjustment circuit is used to alternately apply the first high voltage signal to both ends of the light source according to the second driving signal so that the light source is in AC working state.

[0020] In various embodiments of the present invention, the control module in the flyback boost converter circuit outputs a first control signal to a second switching module. The second switching module converts the first control signal into a second control signal, causing the voltage conversion module to sequentially boost and rectify the DC power supply according to the second control signal, and store the processed energy in a first energy storage module. The first energy storage module stores the energy and outputs a first high-voltage signal at its first terminal. Therefore, the flyback boost converter circuit can boost the DC power supply to obtain a higher high-voltage signal. Attached Figure Description

[0021] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0022] Figure 1a This is a schematic diagram of the structure of one of the light source driving circuits provided in an embodiment of the present invention;

[0023] Figure 1b This is a schematic diagram of the structure of one of the light source driving circuits provided in an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of one of the power switching circuits provided in an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the circuit structure of one power switching circuit provided in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the structure of one of the flyback boost converter circuits provided in an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the circuit structure of one of the flyback boost converter circuits provided in an embodiment of the present invention;

[0028] Figure 6 This is a schematic diagram of the structure of one type of trigger circuit provided in an embodiment of the present invention;

[0029] Figure 7 This is a schematic diagram of the circuit structure of one of the trigger circuits and direction adjustment circuits provided in an embodiment of the present invention;

[0030] Figure 8 This is a schematic diagram of the structure of one of the direction adjustment circuits provided in an embodiment of the present invention;

[0031] Figure 9This is a schematic diagram of the structure of one of the light source driving circuits provided in an embodiment of the present invention;

[0032] Figure 10 This is a schematic diagram of the circuit structure of one of the light source driving circuits provided in an embodiment of the present invention. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0034] Automotive metal halide lamps are high-pressure gas discharge lamps filled with a mixture of inert gases, including xenon, and without the filament found in halogen lamps. They are also known as HID lamps, metal halide lamps, or xenon lamps.

[0035] In the automotive lighting industry, xenon lamps are also known as HID (High-Intensity Discharge) headlights. They use high-pressure xenon gas encased in quartz instead of traditional tungsten filaments, providing higher color temperature and more concentrated illumination. Because xenon lamps use high-voltage current, they significantly reduce the burden on the vehicle's powertrain. The color temperature of automotive xenon lamps is between 4000K and 6000K, far higher than that of ordinary automotive headlight bulbs. They are also brighter; a 4300K ​​xenon lamp emits white and yellow light. Due to their lower color temperature, they appear more yellowish, and their light penetration is stronger than high color temperature lamps, improving driving safety at night and in foggy conditions. The arc of xenon gas continuously discharges between two electrodes.

[0036] However, to drive such a high-quality light source, a sufficiently high ignition voltage of 23KV must be provided to excite the ionization of metal halides. At the same time, a stable voltage and current of 85V 400mA are also required to maintain this working state. This is where metal halide drive power supplies come in. The common power supply system of fuel vehicles is 12VDC or 24VDC. The purpose of metal halide drive power supplies is to upgrade the 12VDC or 24VDC power system of fuel vehicles to meet the working voltage and current environment required by metal halide gas discharge lamps.

[0037] Different vehicle models have different on-board power supply voltages. For example, the on-board power supply voltage of gasoline vehicles is 12VDC or 24VDC, while the first supply voltage of the load circuit in the drive power supply is generally 12VDC or 5VDC. Therefore, different processing circuits are needed for different on-board power supplies to obtain the corresponding supply voltage.

[0038] Please see Figure 1aThis invention provides a light source driving circuit 100, which includes a power switching circuit 10, a flyback boost converter circuit 20, a trigger circuit 30, and a direction adjustment circuit 40.

[0039] The input terminal of the power switching circuit 10 is used to connect to the DC power supply 200, and the output terminal of the power switching circuit 10 is connected to the power supply terminal of the flyback boost converter circuit 20 and the power supply terminal of the trigger circuit 30.

[0040] The first terminal of the flyback boost converter circuit 20 is connected to the DC power supply 200. The second terminal of the flyback boost converter circuit 20 is connected to the first terminal of the direction adjustment circuit 40 and the second terminal of the trigger circuit 30, respectively. The third terminal of the flyback boost converter circuit 20 is connected to the first terminal of the trigger circuit 30, and the fourth terminal of the flyback boost converter circuit 20 is connected to the second terminal of the direction adjustment circuit 40. The output terminal of the power switching circuit 10 is also connected to the direction adjustment circuit 40, and the power supply voltage output by the power switching circuit 10 supplies power to it. The direction adjustment circuit 40 can also be powered by other power sources.

[0041] The third terminal of the direction adjustment circuit 40 is connected to the third terminal of the trigger circuit 30, the fourth terminal of the direction adjustment circuit 40 is connected to the first terminal of the light source 300, the fifth terminal of the direction adjustment circuit 40 is grounded, the second terminal of the light source 300 is connected to the fourth terminal of the trigger circuit 30, and the second terminal of the trigger circuit 30 is connected to the first terminal of the direction adjustment circuit 40 and the second terminal of the flyback boost converter circuit 20.

[0042] The light source driving circuit 100 is used to drive the light source 300, which can be an HID lamp. The following description uses an HID lamp as an example to illustrate the light source driving circuit 100. As mentioned above, the light source driving circuit 100 needs to boost the vehicle power supply to a voltage and current environment suitable for the metal halide gas discharge lamp.

[0043] Specifically, in combination Figure 1a The working principle of the light source driving circuit 100 can be described as follows:

[0044] The DC power supply 200 includes a first DC power supply and a second DC power supply, which are vehicle-mounted power supplies. The power switching circuit 10 switches between the first and second DC power supplies according to the different DC power supplies 200, and performs different processing according to the different DC power supplies 200 to obtain the corresponding supply voltage. This supply voltage powers other circuits of the light source drive circuit 100, specifically the flyback boost converter circuit 20, the trigger circuit 30, and the direction adjustment circuit 40. It can also supply other internal circuits of the light source drive circuit 100 that require power. The circuits powered by the supply voltage are collectively referred to as load circuits.

[0045] The flyback boost converter circuit 20 boosts the voltage of the DC power supply 200 and obtains a first high voltage signal at its second terminal. This first high voltage signal can be used by the subsequent trigger circuit 30 to convert the first high voltage signal into a second high voltage signal to ignite the light source 300. The voltage of the second high voltage signal is much greater than the voltage of the first high voltage signal.

[0046] In this embodiment, the second end of the light source 300 is connected to the third end of the direction adjustment circuit 40 through the fourth and third ends of the trigger circuit 30. When the first end of the direction adjustment circuit 40 is connected to the third end, the second end of the light source 300 can be connected to the second end of the flyback boost converter circuit 20, i.e., it can receive the first high-voltage signal. When the fourth and fifth ends of the direction adjustment circuit 40 are connected, the first end of the light source 300 can be grounded through the fourth and fifth ends of the direction adjustment circuit 40. When the first terminal of the direction adjustment circuit 40 is connected to the third terminal of the direction adjustment circuit 40, and the fourth terminal of the direction adjustment circuit 40 is connected to the fifth terminal of the direction adjustment circuit 40, the second terminal of the flyback boost converter circuit 20, the first terminal of the direction adjustment circuit 40, the third terminal of the direction adjustment circuit 40, the third terminal of the trigger circuit 30, the fourth terminal of the trigger circuit 30, the second terminal of the light source 300, the first terminal of the light source 300, the fourth terminal of the direction adjustment circuit 40, and the fifth terminal of the direction adjustment circuit 40 form a first drive circuit.

[0047] It can be understood that the third terminal of the trigger circuit 30 and the fourth terminal of the trigger circuit 30 are connected inside the trigger circuit 30.

[0048] The sixth terminal of the flyback boost converter circuit 20 is connected to either the first or second terminal of the light source 300. Through this connection, the sixth terminal of the flyback boost converter circuit 20 can detect the current in the first drive circuit, i.e., the current of the light source 300, and drive the direction adjustment circuit 40 and the trigger circuit 30 to operate based on the magnitude of the light source 300's current. Specifically, when the current of the light source 300 is less than or equal to a first preset value, the flyback boost converter circuit 20 outputs a first drive signal to the trigger circuit 30 through its third terminal. When the current of the light source 300 is greater than or equal to a second preset value, the flyback boost converter circuit 20 outputs a second drive signal to the drive direction adjustment circuit 40 through its fourth terminal.

[0049] The sixth terminal of the flyback boost converter circuit 20 can be directly or indirectly connected to the first or second terminal of the light source 300.

[0050] The trigger circuit 30 converts the first high-voltage signal into a second high-voltage signal according to the first driving signal. The second high-voltage signal acts on both ends of the HID lamp, causing the xenon electrons in the HID lamp to ionize and generate a light source between the two electrodes of the HID lamp. This light source produces a white, ultra-intense electric arc, which ignites the HID lamp. After successful ignition, the HID lamp is broken down, and its two ends become conductive. The voltage across the HID lamp drops rapidly. Furthermore, after successful ignition, when the flyback boost converter circuit 20 detects that the current flowing through the HID lamp is greater than or equal to a second preset value, it will stop outputting the first driving signal to the trigger circuit 30, causing the trigger circuit 30 to exit the ignition state.

[0051] The direction adjustment circuit 40 can alternately apply a first high-voltage signal to both ends of the HID lamp according to the second driving signal. This first high-voltage signal can sequentially pass through the third terminal of the direction adjustment circuit 40, the third terminal of the trigger circuit 30, and the fourth terminal of the trigger circuit 30 to the second terminal of the HID lamp. The first terminal of the HID lamp can be grounded through the fourth terminal and the fifth terminal of the direction adjustment circuit 40. The fourth and fifth terminals of the direction adjustment circuit 40 are connected. The first high-voltage signal can also sequentially pass through the... The fourth terminal of the direction adjustment circuit 40 acts on the first terminal of the HID lamp. The second terminal of the HID lamp can be grounded through the fourth terminal of the trigger circuit 30, the third terminal of the trigger circuit 30, the third terminal of the direction adjustment circuit 40, and the fifth terminal of the direction adjustment circuit 40. The third terminal and the fifth terminal of the direction adjustment circuit 40 are connected, so that the first high voltage signal alternately acts on the two ends of the HID lamp to maintain the two ends of the HID lamp in AC state, which can extend the service life of the HID lamp electrodes and ensure the working life of the HID lamp.

[0052] In some embodiments, the direction adjustment circuit 40 may be omitted, such as... Figure 1b As shown, in this embodiment, the second terminal of the flyback boost converter circuit 20 is connected to the second terminal and the third terminal of the trigger circuit 30, respectively. The third terminal of the flyback boost converter circuit 20 is connected to the first terminal of the trigger circuit 30. The sixth terminal of the flyback boost converter circuit 20 is connected to the first or second terminal of the light source 300. The fourth terminal of the trigger circuit 30 is connected to the second terminal of the light source 300. The first terminal of the light source 300 is grounded.

[0053] The flyback boost converter circuit 20 boosts the voltage of the DC power supply 200 and obtains a first high voltage signal at its second terminal. This first high voltage signal directly acts on the positive terminal (second terminal) of the light source 300, while the negative terminal of the light source 300 is grounded. At this time, the first high voltage signal causes the two ends of the light source 300 to operate in a DC state.

[0054] The sixth terminal of the flyback boost converter circuit 20 detects the current of the light source 300. When the current of the light source 300 is less than or equal to a first preset value, the flyback boost converter circuit 20 outputs a first driving signal to the trigger circuit 30 through its third terminal. The trigger circuit 30 converts the first high-voltage signal into a second high-voltage signal according to the first driving signal to ignite the light source 300.

[0055] In summary, the light source driving circuit 100 can provide the ignition voltage required for the light source 300 to operate through the trigger circuit 30, and maintain the voltage and current for the normal operation of the light source 300 through the direction adjustment circuit 40, thereby realizing the function of driving the light source 300. Furthermore, the light source driving circuit 100 is compatible with different vehicle power supplies through the power switching circuit 10, thus making it suitable for different vehicle models and offering greater flexibility and convenience.

[0056] The DC power supply 200 can have a voltage of 12V or 24V. The supply voltage can be 12V or 5V. The first high-voltage signal can be between 17V and 28V, and the second high-voltage signal can be 23KV.

[0057] In some embodiments, please refer to Figure 2 , Figure 2 This is a schematic diagram of a power switching circuit provided in an embodiment of the present invention, as shown below. Figure 2 As shown, the power switching circuit 10 includes a selection circuit 11, a voltage regulation circuit 12, and a voltage conversion circuit 13. The output terminal of the power switching circuit 10 includes a first output terminal, which is port PT1. Correspondingly, the power supply voltage includes a first power supply voltage.

[0058] The first terminal of the selection circuit 11 is connected to the DC power supply 200, the second terminal of the selection circuit 11 is connected to the first terminal of the voltage regulation circuit 12, and the third terminal of the selection circuit 11 is connected to the first terminal of the voltage conversion circuit 13. The first terminal of the selection circuit 11 serves as the input terminal of the power switching circuit 10, and the second terminals of both the voltage regulation circuit 12 and the voltage conversion circuit 13 serve as the first output terminals of the power switching circuit 10.

[0059] The DC power supply 200 includes a first DC power supply and a second DC power supply. When the DC power supply 200 is the first DC power supply, the first terminal of the selection circuit 11 is connected to the second terminal of the selection circuit 11, so that the first DC power supply acts on the first terminal of the voltage regulation circuit 12, so that the voltage regulation circuit 12 performs voltage regulation on the first DC power supply and outputs a first supply voltage to supply power to the load circuit.

[0060] When the DC power supply 200 is the second DC power supply, the first terminal of the selection circuit 11 is connected to the third terminal of the selection circuit 11, so that the second DC power supply acts on the first terminal of the voltage conversion processing circuit 13, so that the voltage conversion processing circuit 13 performs voltage conversion processing on the second DC power supply and outputs the first supply voltage to supply power to the load circuit.

[0061] Voltage conversion processing can be either boost or buck conversion.

[0062] The voltage of the first DC power supply is lower than the voltage of the second DC power supply. For example, if the DC power supply is an automotive power supply, the voltage of the first DC power supply can be 12V, and the voltage of the second DC power supply can be 24V. In other embodiments, the voltages of the first and second DC power supplies can also be changed depending on the type of DC power supply.

[0063] The load circuit can be any circuit module in the light source driver circuit that requires power supply, or it can be a load module of the light source driver circuit, such as the light source 300.

[0064] Therefore, this power switching circuit can automatically switch the corresponding processing circuit to handle the DC power supply based on its type, and then output the first supply voltage to the load circuit. This power switching circuit is compatible with different vehicle power supplies, making it more versatile and flexible. Compared to situations requiring multiple vehicle power supply systems, this power switching circuit reduces circuit costs and losses.

[0065] like Figure 2 As shown, the selection circuit 11 includes a first voltage regulator module 111 and a first switch module 112.

[0066] The first terminal of the first voltage regulator module 111 is connected to the DC power supply 200, the second terminal of the first voltage regulator module 111 is connected to the fourth terminal of the first switch module 112, the first terminal of the first switch module 112 is connected to the DC power supply 200, the second terminal of the first switch module 112 is connected to the first terminal of the voltage regulation processing circuit 12, and the third terminal of the first switch module 112 is connected to the first terminal of the voltage conversion processing circuit 13.

[0067] The first terminal of the first voltage regulator module 111 and the first terminal of the first switch module 112 both serve as the first terminal of the selection circuit 11, the second terminal of the first switch module 112 serves as the second terminal of the selection circuit 11, and the third terminal of the first switch module 112 serves as the third terminal of the selection circuit 11.

[0068] When the DC power supply 200 is the second DC power supply, the first voltage regulator module 111 is in the on state, so that the first terminal of the first switch module 112 is connected to the third terminal of the first switch module 112. When the DC power supply 200 is the first DC power supply, the first voltage regulator module 111 is in the off state, so that the first terminal of the first switch module 112 is connected to the second terminal of the first switch module 112.

[0069] like Figure 2 As shown, the first switch module 112 includes a first switch unit 1121, a second switch unit 1122, and a third switch unit 1123.

[0070] The first terminal of the first switching unit 1121 is connected to the DC power supply 200, the second terminal of the first switching unit 1121 is connected to the second terminal of the first voltage regulator module 111, and the third terminal of the first switching unit 1121 is connected to the third terminal of the second switching unit 1122.

[0071] The first terminal of the second switching unit 1122 is connected to the DC power supply 200, and the second terminal of the second switching unit 1122 is connected to the first terminal of the voltage regulation circuit 12.

[0072] The first terminal of the third switching unit 1123 is connected to the DC power supply 200, the second terminal of the third switching unit 1123 is connected to the first terminal of the voltage conversion processing circuit 13, and the third terminal of the third switching unit 1123 is connected to the fourth terminal of the first switching unit 1121.

[0073] When the DC power supply is the second DC power supply, the first voltage regulator module 111 is reverse-broken down, the first switching unit 1121 is in the on state, the second switching unit 1122 is in the off state, and the third switching unit 1123 is in the on state, so that the second DC power supply is connected to the first terminal of the voltage conversion processing circuit 12, and the voltage conversion processing circuit 12 performs voltage conversion processing on the second DC power supply and outputs the first supply voltage.

[0074] When the DC power supply is the first DC power supply, the first voltage regulator module 111 is not broken down, the first switching unit 1121 is in the off state, the second switching unit 1122 is in the on state, and the third switching unit 1123 is in the off state, so that the first DC power supply is connected to the first terminal of the voltage regulation circuit 13, and the voltage regulation circuit 13 outputs the first supply voltage after voltage regulation.

[0075] When the first voltage regulator module 111 is reversely broken down, the first voltage regulator module 111 is in the conducting state; when the first voltage regulator module 111 is not broken down, the first voltage regulator module 111 is in the cut-off state.

[0076] The use of multiple switching units to achieve automatic switching of DC power supply 200 improves the reliability of the system.

[0077] like Figure 2 As shown, the voltage regulation circuit 12 includes a second voltage regulation module 121 and a first unidirectional conduction module 122.

[0078] The first end of the second voltage regulator module 121 is connected to the second end of the selection circuit 11, and the second end of the second voltage regulator module 121 is connected to the first end of the first unidirectional conduction module 122. The second voltage regulator module 121 is used to regulate the voltage of the first DC power supply.

[0079] The second terminal of the first unidirectional conduction module 122 serves as the second terminal of the voltage regulation circuit 12. The first unidirectional conduction module 122 is used to prevent the first power supply voltage output from the second terminal of the first unidirectional conduction module 122 from flowing back to the second voltage regulation module 121.

[0080] The second voltage regulator module 121 can regulate the voltage of the first DC power supply. The first DC power supply is applied to the first terminal of the second voltage regulator module 121. After being regulated by the second voltage regulator module 121, a regulated signal is output through the second terminal of the second voltage regulator module 121. This regulated signal is then output as a first supply voltage through the second terminal of the first unidirectional conduction module 122. When the first supply voltage is output through the second terminal of the first unidirectional conduction module 122, the first unidirectional conduction module 122 can prevent the first supply voltage from flowing back to the second voltage regulator module 121, preventing crosstalk and improving power supply safety.

[0081] like Figure 2 As shown, the power switching circuit 10 further includes a voltage regulation and conversion processing circuit 14. The output terminal of the power switching circuit 10 also includes a second output terminal, and correspondingly, the supply voltage includes a second supply voltage. The first terminal of the voltage regulation and conversion processing circuit 14 is connected to the second terminal of the voltage regulation processing circuit 12 and the second terminal of the voltage conversion processing circuit 13, respectively. The second terminal of the voltage regulation and conversion processing circuit 14 serves as the second output terminal of the power switching circuit 10, which is port PT2. The voltage regulation and conversion processing circuit 14 is used to regulate and convert the first supply voltage to obtain the second supply voltage, and outputs the second supply voltage at port PT2.

[0082] Please see Figure 3 , Figure 3 This is a schematic diagram of the circuit structure of a power switching circuit provided in an embodiment of the present invention. Figure 3 As shown, the first voltage regulator module 111 includes Zener diodes ZD1 and ZD2, the first switching unit 1121 includes transistors Q1, Q2, and Q3, resistors R1, R2, R3, R4, R5, R6, and R7, the second switching unit 1122 includes transistor Q4 and resistor R8, and the third switching unit 1123 includes transistor Q5 and resistor R9.

[0083] Specifically, the anode of Zener diode ZD1 is connected to the cathode of Zener diode ZD2. The anode of Zener diode ZD2 is connected to one end of resistor R2, one end of resistor R1, and one end of resistor R4. The other end of resistor R2 is connected to the base of transistor Q1, and the other end of resistor R4 is connected to the base of transistor Q2. The collector of transistor Q1 is connected to one end of resistor R3 and one end of resistor R6, and the other end of resistor R6 is connected to the base of transistor Q3. The collector of transistor Q2 is connected to one end of resistor R5 and one end of resistor R9, and the other end of resistor R9 is connected to the base of transistor Q5. The collector of transistor Q3 is connected to one end of resistor R7 and one end of resistor R8, and the other end of resistor R8 is connected to the base of transistor Q4. The collector of transistor Q4 is connected to the first terminal of the voltage regulation circuit 12, and the collector of transistor Q5 is connected to the first terminal of the voltage conversion circuit 13.

[0084] The cathode of Zener diode ZD1, the other end of resistor R3, the other end of resistor R5, the other end of resistor R7, the emitter of transistor Q4, and the emitter of transistor Q5 are all connected to the DC power supply 200. The other end of resistor R1, the emitter of transistor Q1, the emitter of transistor Q2, and the emitter of transistor Q3 are all grounded.

[0085] The first terminal of the first voltage regulator module 111 is the cathode of the Zener diode ZD1, and the second terminal of the first voltage regulator module 111 is the anode of the Zener diode ZD2. The first terminal of the first switching unit 1121 is the common connection terminal of resistors R3, R5, and R7, the second terminal of the first switching unit 1121 is the common connection terminal of resistor R2 and Zener diode ZD2, the third terminal of the first switching unit 1121 is the collector of transistor Q3, and the fourth terminal of the first switching unit 1121 is the collector of transistor Q2.

[0086] The first voltage regulator module 111 is in a conducting state when both Zener diodes ZD1 and ZD2 are reverse-biased and broken down; the first voltage regulator module 111 is in a cut-off state when neither Zener diodes ZD1 nor ZD2 are reverse-biased and broken down. The first switching unit 1121 is in a conducting state when transistors Q1 and Q2 are both on, and transistor Q3 is off; the first switching unit 1121 is in a cut-off state when transistors Q1 and Q2 are both off, and transistor Q3 is on. The second switching unit 1122 is in a conducting state when transistor Q4 is on, and the second switching unit 1122 is in a cut-off state when transistor Q4 is off. The third switching unit 1123 is in a conducting state when transistor Q5 is on, and the third switching unit 1123 is in a cut-off state when transistor Q5 is off.

[0087] In this embodiment of the invention, different voltages in the DC power supply 200 result in different operating states for Zener diodes ZD1 and ZD2, thereby controlling the on / off states of the corresponding transistors. The on / off states of the transistors form different paths, causing the DC power supply 200 to act on the first terminal of the voltage regulation circuit 12 or the first terminal of the voltage conversion circuit 13, so that the voltage regulation circuit 12 or the voltage conversion circuit 13 can perform corresponding processing.

[0088] The voltage regulation values ​​of Zener diodes ZD1 and ZD2 can be selected based on the voltages of the first and second DC power supplies. Using two Zener diodes can improve the reliability of the power supply.

[0089] In this embodiment of the invention, transistors Q1, Q2, and Q3 are all NPN transistors, and transistors Q4 and Q5 are both PNP transistors. The NPN transistors can be of model FMMT493, and the PNP transistors can be of model FMMT593.

[0090] like Figure 3 As shown, the second voltage regulator module 121 includes a resistor R10 and a voltage regulator chip U1, and the first unidirectional conduction module 122 includes a diode D1.

[0091] One end of resistor R10 is connected to the second end of the selection circuit 11, the other end of resistor R10 is connected to the input end of voltage regulator chip U1, the output end of voltage regulator chip U1 is connected to the anode of diode D1, and the ground end of voltage regulator chip U1 is grounded.

[0092] One end of resistor R11 is connected to the DC power supply 200, and the other end of resistor R11, together with the cathode of diode D1, serves as the second terminal of the first unidirectional conduction module 122. One end of resistor R10 serves as the first terminal of the second voltage regulator module 121, the output terminal of voltage regulator chip U1 serves as the second terminal of the second voltage regulator module 121, and the anode of diode D1 serves as the first terminal of the first unidirectional conduction module 122.

[0093] In this embodiment of the invention, the voltage regulator chip U1 can be MC7812, which is a three-terminal voltage regulator integrated circuit IC chip, and can be packaged in T0252. The diode D1 can be US1J.

[0094] The second voltage regulator module 121 may further include several filter capacitors, which can be configured at the input and output terminals of the voltage regulator chip U1 to filter the voltage of the first DC power supply and the first supply voltage. Specifically, the second voltage regulator module 121 also includes filter capacitors C1, C2, C3, and C4. One end of filter capacitor C1 and one end of filter capacitor C2 are connected to the input terminal of the voltage regulator chip U1, and the other end of filter capacitor C1 and the other end of filter capacitor C2 are connected to ground. One end of filter capacitor C3 and one end of filter capacitor C4 are connected to the output terminal of the voltage regulator chip U1, and the other end of filter capacitor C3 and the other end of filter capacitor C4 are connected to ground. Filter capacitors C1 and C2 together filter the voltage signal of the first DC power supply, and filter capacitors C3 and C4 together filter the voltage signal of the first supply voltage.

[0095] like Figure 3 As shown, the voltage conversion processing circuit includes a switching power supply chip U2, a resistor R12, a diode D2, a diode D3, a diode D4, a diode D5, an inductor L1, a Zener diode ZD3, a capacitor C11, a capacitor C12, a capacitor C13, a capacitor C14, and a capacitor C15.

[0096] The first terminal of the switching power supply chip U2 is connected to the third terminal of the selection circuit. The second terminal of the switching power supply chip U2 is connected to the cathode of diode D5, one end of capacitor C11, one end of capacitor C12, and one end of capacitor C13. The third terminal of the switching power supply chip U2 is connected to one end of resistor R12 and the other end of capacitor C11. The fourth terminal of the switching power supply chip U2 is connected to the cathode of diode D2 and the other end of capacitor C12.

[0097] The other end of resistor R12 is connected to the anode of Zener diode ZD3. The cathode of Zener diode ZD3 is connected to the anode of diode D2, the cathode of diode D3, and the other end of capacitor C13. The anode of diode D3 is connected to the anode of diode D4. The cathode of diode D4 serves as the second terminal of the voltage conversion processing circuit. One end of inductor L1 is connected to the cathode of diode D5 and the cathode of diode D3 via capacitor C13. The other end of inductor L1 is connected to the anode of diode D3, the anode of diode D4, one end of capacitor C14, and one end of capacitor C15. The anode of diode D5, the other end of capacitor C14, and the other end of capacitor C15 are all grounded.

[0098] like Figure 3 As shown, the voltage regulation and voltage conversion processing circuit 14 includes a voltage regulator chip U3. The input terminal of the voltage regulator chip U3 is connected to the second terminal of the voltage regulation processing circuit 12 and the second terminal of the voltage conversion processing circuit 13, respectively. That is, the input terminal of the voltage regulator chip U3 serves as the first terminal of the voltage regulation and voltage conversion processing circuit 14, and the output terminal of the voltage regulator chip U3 serves as the second terminal of the voltage regulation and voltage conversion processing circuit 14.

[0099] The first terminal of the switching power supply chip U2 serves as the first terminal of the voltage conversion processing circuit.

[0100] The input terminal of the voltage regulator chip U3 is connected to the first power supply voltage output by the voltage regulation processing circuit 12 and the voltage conversion processing circuit 13. The voltage regulator chip U3 performs voltage reduction and regulation processing on the first power supply voltage, and outputs the second power supply voltage at its output terminal after processing.

[0101] In this embodiment of the invention, the first power supply voltage is +12V, the second power supply voltage is +5V, and the voltage regulator chip U3 is model 78M05.

[0102] The voltage regulation and voltage conversion processing circuit 14 may also include several filter capacitors. The filter capacitors can be configured at the input and output terminals of the voltage regulator chip U3 to filter the first supply voltage or the second supply voltage.

[0103] Combination Figure 3 The working principle of the power switching circuit 10 can be described as follows:

[0104] When the DC power supply 200 is the first DC power supply, the VCC terminal is the first DC power supply, the Zener diodes ZD1 and ZD2 are cut off, and the transistors Q1 and Q2 are cut off because their bases are at a low level. The first DC power supply acts on the bases of transistors Q3 and Q5. Therefore, transistor Q3 is turned on, pulling down the base level of transistor Q4, making transistor Q4 turn on, while transistor Q5 is cut off because its base is at a high level. The first DC power supply acts on the input terminal of the voltage regulator chip U1 through the emitter and collector of transistor Q4. After being regulated by the voltage regulator chip U1, the first supply voltage is output. The first supply voltage is then regulated and stepped down by the voltage regulator chip U3 to output the second supply voltage.

[0105] When the DC power supply 200 is the second DC power supply, the VCC terminal is the second DC power supply. Zener diodes ZD1 and ZD2 are reverse-biased and conduct. Transistors Q1 and Q2 conduct because their bases are at a high level. When transistor Q1 conducts, it pulls down the base level of transistor Q3, causing transistor Q3 to turn off. The second DC power supply acts on the base of transistor Q4, causing transistor Q4 to turn off. The conduction of transistor Q2 pulls down the base level of transistor Q5, causing transistor Q5 to conduct because its base is at a low level. The second DC power supply acts on the input terminal of the switching power supply chip U2 through the emitter and collector of transistor Q5. After being stepped down by the switching power supply chip U2, the first supply voltage is output. The first supply voltage is then stepped down and regulated by the voltage regulator chip U3 to output the second supply voltage.

[0106] In summary, this power switching circuit can automatically switch the corresponding processing circuit to handle the DC power supply based on its type, thereby outputting the first supply voltage to the load circuit. Therefore, this power switching circuit is compatible with different vehicle power supplies, offering greater applicability and flexibility. Compared to scenarios requiring multiple vehicle power supply systems, this power switching circuit reduces circuit costs and losses.

[0107] The flyback boost converter circuit 20 is used to convert the voltage of the vehicle power supply into a first high-voltage signal to maintain the normal operation of the light source 300, or to supplement the voltage signal to the light source 300 during the initial startup phase. However, to achieve a higher first high-voltage signal, the first transformer of the conventional flyback boost converter circuit 20 has a larger number of coil turns, which increases the circuit cost. At the same time, when supplementing the voltage signal to the light source 300, underpowerment is prone to occur.

[0108] Please see Figure 4 , Figure 4 This is a schematic diagram of a flyback boost converter circuit provided in an embodiment of the present invention, as shown below. Figure 4As shown, the flyback boost converter circuit 20 includes a control module 201, a second switching module 202, a voltage conversion module 203, and a first energy storage module 204.

[0109] The first end of the second switch module 202 is connected to port PT1 for receiving the first power supply voltage. The second end of the second switch module 202 is connected to the first end of the control module 201. The third end of the second switch module 202 is connected to the first end of the voltage conversion module 203.

[0110] The second terminal of the voltage conversion module 203 is connected to the DC power supply 200, and the third terminal of the voltage conversion module 203 is connected to the first terminal of the first energy storage module 204 and port PT3, respectively.

[0111] The control module 201 outputs a first control signal to the second switch module 202 through its first terminal, acting on the second terminal of the second switch module 202. This causes the second switch module 202 to convert the first control signal into a second control signal. The second control signal acts on the first terminal of the voltage conversion module 203, causing the voltage conversion module 203 to sequentially boost and rectify the DC power supply 200 according to the second control signal. The processed energy is then stored in the first energy storage module 204. The first energy storage module 204 stores the energy and outputs a first high-voltage signal at its first terminal. This first high-voltage signal acts on the light source 300 and the trigger circuit 30 to ignite the light source 300 and maintain its normal operation.

[0112] The flyback boost converter circuit can control the voltage conversion module 203 to boost and rectify the DC power supply 200 through the first control signal output by the control module 201, so that the voltage conversion module 203 stores the processed energy in the first energy storage module 204, thereby enabling the first energy storage module 204 to output a first high voltage signal, realizing the boost conversion from a lower voltage signal to a higher voltage signal, and achieving voltage multiplication.

[0113] The first control signal output by the control module 201 is a PWM wave, and the voltage of the first high-voltage signal can be adjusted by regulating the frequency of the PWM wave. The second control signal is a signal with the opposite state to the first control signal, and it is a PWM wave with the same frequency as the first control signal. Specifically, when the first control signal is at a high level, the second switch module 202 is in the on state, and the second control signal is at a low level; when the first control signal is at a low level, the second switch module 202 is in the off state, and the second control signal is at a high level. The frequency of the PWM wave can be set as needed; in this embodiment, it is 66kHz.

[0114] At the same time, such as Figure 4 As shown, the third terminal of the control module 201 is connected to port PT5, which is used to output the first drive signal of the trigger circuit 30, and the fourth terminal of the control module 201 is connected to port PT4, which is used to output the second drive signal of the direction adjustment circuit 40.

[0115] The control module 201 is a central processing unit composed of one or a few large-scale integrated circuits. These circuits perform the functions of control units and arithmetic logic units. The control module 201 can perform operations such as fetching instructions, executing instructions, and exchanging information with external memory and logic units. It is the arithmetic control part of the microcomputer and can form a microcomputer together with memory and peripheral circuit chips.

[0116] In some embodiments, such as Figure 4 As shown, the flyback boost converter circuit 20 also includes a clamping module 205. One end of the clamping module 205 is connected to the DC power supply 200 and the second end of the voltage conversion module 203, respectively, and the other end of the clamping module 205 is connected to the fourth end of the voltage conversion module 203. When the second switching module 202 is in the on state, the clamping module 205 is used to clamp the voltage at the fourth end of the voltage conversion module 203.

[0117] When the second switch module 202 is in the ON state, the second control signal is at a low level, the third terminal of the voltage conversion module 203 is at a low level, and simultaneously, the fourth terminal of the voltage conversion module 203 is at a high level. The high level at the fourth terminal of the voltage conversion module 203 may damage the voltage conversion module 203. Therefore, the clamping module can clamp the voltage at the fourth terminal of the voltage conversion module 203 to protect it.

[0118] In some embodiments, such as Figure 4 As shown, the flyback boost converter circuit 20 also includes a first acquisition circuit 206 and a second acquisition circuit 207.

[0119] The first terminal of the first acquisition circuit 206 is connected to the DC power supply 200, and the second terminal of the first acquisition circuit 206 is connected to the fifth terminal of the control module 201. The first acquisition circuit 206 is used to detect the voltage of the DC power supply 200.

[0120] The first end of the second acquisition circuit 207 is connected to the first end of the first energy storage module 204. Specifically, the first end of the second acquisition circuit 207 is connected to port PT3, and the second end of the second acquisition circuit is connected to the second end of the control module 201. The second acquisition circuit is used to detect the voltage at the first end of the first energy storage module 204.

[0121] When the circuit is working normally, the voltage at the first terminal of the first energy storage module 204 is the voltage value corresponding to the first high voltage signal, which is the voltage at which the light source 30 enters normal working state after ignition.

[0122] In this embodiment of the invention, the voltage at the first end of the first energy storage module 204 is either the voltage applied to the light source 30 through the direction adjustment circuit 40 or the voltage applied directly to the light source 30. If the DC power supply 200 is a vehicle power supply, the first acquisition circuit 206 detects the voltage of the vehicle power supply, and the second acquisition circuit 207 samples the voltage of the light source 30.

[0123] In some embodiments, the flyback boost converter circuit 20 further includes a third acquisition circuit 208. The third acquisition circuit 208 is connected to the first or second end of the light source 300 and is connected to the sixth end of the control module 201 through port PT6. The third acquisition circuit 208 is used to acquire the current of the light source 300 and transmit the sampled current of the light source 300 to the sixth end of the control module 201 for the control module 201 to receive and analyze, so as to obtain the current value of the light source 300.

[0124] When the second acquisition circuit 207 detects the first high-voltage signal, but the third acquisition circuit 208 does not detect the current of the light source 300, it indicates that the light source 300 is not in working state. The control module 201 determines that the current of the light source 300 is less than or equal to the first preset value, and then sends a first drive signal through its fourth terminal to drive the trigger circuit 30 to work, so as to ignite the light source under high voltage.

[0125] After successful ignition, the third acquisition circuit 208 can detect the current of the light source 300. When the current of the light source 300 is greater than or equal to the second preset value, the control module 201 stops sending the first drive signal, causing the trigger circuit 30 to exit ignition. The first drive signal is a pulse signal.

[0126] The third acquisition circuit 208 can also be connected to the first or second end of the light source 300 through the direction adjustment circuit 40. Specifically, the third acquisition circuit 208 can also be connected to the first or second end of the light source 300 through the sixth end of the direction adjustment circuit 40 to detect the current of the light source 300.

[0127] When the control module 201 stops outputting the first drive signal, the control module 201 outputs the second drive signal to the direction adjustment circuit 40 through port PT4, so that the direction adjustment circuit 40 alternately applies the first high voltage signal to both ends of the light source 300 according to the second drive signal, so that the light source 300 is in AC working state.

[0128] Please see Figure 5 , Figure 5 This is a schematic diagram of the circuit structure of a flyback boost converter circuit provided in an embodiment of the present invention, as shown below. Figure 5 As shown, the voltage conversion module 203 includes a first transformer T1, a MOSFET Q8, and a diode D8.

[0129] The first transformer T1 includes a first primary winding and a second secondary winding. The first end of the first primary winding is connected to the DC power supply 200 (VCC terminal). The second end of the first primary winding is connected to the drain of the MOSFET Q8 and the first end of the second secondary winding. The second end of the second secondary winding is connected to the anode of the diode D8. The cathode of the diode D8 is connected to the first end of the first energy storage module 204 and the port PT3. The gate of the MOSFET Q8 is connected to the third end of the second switching module 202. The source of the MOSFET Q8 is grounded.

[0130] MOSFET Q8 is an NMOS transistor, and its model number can be UTC50N100.

[0131] The gate of the MOS transistor Q8 is the first terminal of the voltage conversion module 203, the first terminal of the first primary winding is the second terminal of the voltage conversion module 203, the cathode of the diode D8 is the third terminal of the voltage conversion module 203, and the drain of the MOS transistor, the second terminal of the first primary winding, and the first terminal of the first primary winding together serve as the fourth terminal of the voltage conversion module 203.

[0132] In this embodiment of the invention, the first end of the first primary winding of the first transformer T1 is connected to the second end of the first primary winding, forming an autotransformer connection. Compared to the conventional first transformer T1 connection method that grounds the first end of the first primary winding, this connection method of the first transformer T1 can output a higher voltage with the same winding turns ratio, and requires fewer coil turns to achieve the same output voltage.

[0133] Therefore, the autotransformer T1 in this embodiment of the invention can reduce circuit costs and output higher voltage.

[0134] Meanwhile, since the first transformer T1 is autotransformed, it can directly obtain some electrical energy from the vehicle power supply to provide energy to the light source 300. This provides the light source 300 with the energy needed to accelerate the separation of metal halides after being broken down by high voltage. Directly obtaining energy from the vehicle power supply ensures sufficient replenishment, preventing the light source 300 from running out of power and guaranteeing its stable and normal operation, thereby improving its efficiency. In contrast, the traditional connection method of the first transformer T1 only provides the energy needed for accelerated metal halide separation to the light source 300 through the first energy storage module 204. The amount of replenished energy depends on the energy stored in the first energy storage module 204, which may result in insufficient replenishment and cause the light source 300 to run out of power.

[0135] like Figure 5 As shown, the first energy storage module 204 includes a resistor R13, a diode D6, and a capacitor C5.

[0136] One end of resistor R13 is connected to the cathode of diode D8 and the cathode of diode D6 respectively, and the other end of resistor R13 is connected to the anode of diode D6 and one end of capacitor C5 respectively. The other end of capacitor C5 is grounded.

[0137] One end of resistor R13 and the cathode of diode D6 serve as the first terminal of the first energy storage module 204, and the other end of capacitor C5 serves as the second terminal of the first energy storage module 204.

[0138] The DC power supply 200 is boosted by coupling the first primary winding of the first transformer T1 to the first secondary winding. The boosted signal is rectified by diode D8, and the rectified energy charges and stores the energy in capacitor C5 through resistor R13. Capacitor C5 then outputs a first high-voltage signal to the direction adjustment circuit 40 and the trigger circuit 30. The trigger circuit 30 converts the first high-voltage signal into a second high-voltage signal according to the first drive signal to ignite the light source 300, and the direction adjustment circuit 30 alternately applies the first high-voltage signal to both ends of the light source 300 according to the second drive signal, so that the light source 300 is in AC operating mode.

[0139] In this embodiment of the invention, capacitor C5 can also provide the energy required for accelerated separation of internal metal halides in the light source 300. However, this method is generally used when the second DC power supply 200 (higher power supply voltage) is powered. When the light source 300 is broken down by high voltage, the voltage across the light source 300 is between 17V and 28V. At this time, the energy stored in capacitor C5 is provided to the light source 300 through diode D6 and direction adjustment circuit 40 to complete the energy required for accelerated separation of internal metal halides in the light source.

[0140] like Figure 5As shown, the second switch module 202 includes resistors R14, R15, and R16, transistor Q6, and transistor Q7.

[0141] One end of resistor R14 is connected to the first terminal of the control module 201. The other end of resistor R14 is connected to the base of transistors Q6 and Q7 respectively. The emitter of transistor Q6 is grounded. The collector of transistor Q6 is connected to the collector of transistor Q7 and one end of resistor R15 respectively. The emitter of transistor Q7 is connected to port PT1 for receiving the first supply voltage. The other end of resistor R15 is connected to one end of resistor R16 and the gate of MOSFET Q8 respectively. The other end of resistor R16 is grounded.

[0142] Transistor Q6 is an NPN transistor, and its model number can be 8050. Transistor Q7 can be a PNP transistor, and its model number can be 8550.

[0143] The emitter of transistor Q7 serves as the first terminal of the second switch module 202, one end of resistor R14 serves as the second terminal of the second switch module 202, and the other end of resistor R15 and one end of resistor R16 together serve as the third terminal of the second switch module 202.

[0144] The conduction state of the second switch module 202 means that transistor Q6 is on and transistor Q7 is off, and the cutoff state of the second switch module 202 means that transistor Q6 is off and transistor Q7 is on.

[0145] In some embodiments, the control module 201 may also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), an ARM (Advanced RISC Machine) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination of these components; it may also be any conventional processor, controller, microcontroller, or state machine; it may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0146] In this embodiment of the invention, the control module 201 includes a microcontroller U4. Pin 1 of the microcontroller U4 is connected to resistor R14 and is used to output a first control signal. Pin 2 of the microcontroller U4 is connected to the second acquisition circuit 207 and is used to acquire the voltage of the light source 300. Pin 3 of the microcontroller U4 is connected to the direction adjustment circuit 40 and is used to output a second drive signal of the direction adjustment circuit 40. Pin 4 of the microcontroller U4 is connected to the trigger circuit 30 and is used to output a first drive signal of the trigger circuit 30. Pin 5 of the microcontroller U4 is connected to the first acquisition circuit 206 and is used to acquire the voltage of the DC power supply 200. Pin 6 of the microcontroller U4 is used to acquire the current of the light source 300. The power supply voltage of the microcontroller U4 is +5V, which can be obtained from the second terminal of the voltage regulator and voltage conversion processing circuit 14.

[0147] like Figure 5 As shown, the clamping module 205 includes a capacitor C6, a diode D7, and a resistor R17.

[0148] One end of capacitor C6 is connected to one end of resistor R17 and the first end of the first primary winding, respectively. The other end of capacitor C6 is connected to the other end of resistor R17 and the cathode of diode D7, respectively. The anode of diode D7 is connected to the second end of the first primary winding and the first end of the first primary winding, respectively.

[0149] The diode D7 can be a 1N4148.

[0150] One end of capacitor C6 and one end of resistor R17 together serve as the first end of clamping module 205, and the anode of diode D7 serves as the second end of clamping module 205.

[0151] like Figure 5 As shown, the first acquisition circuit 206 includes resistors R18, R19, R20 and capacitor C7, and the second acquisition circuit 207 includes resistors R21, R22, R23 and capacitor C8.

[0152] One end of resistor R18 is connected to the DC power supply 200, and the other end of resistor R18 is connected to one end of resistor R19 and one end of resistor R20 respectively. The other end of resistor R19 and one end of capacitor C7 are grounded together, and the other end of capacitor C7 and the other end of resistor R20 are connected to the fifth terminal of the control module 201.

[0153] One end of resistor R21 is connected to port PT3, and the other end of resistor R21 is connected to one end of resistor R23 and one end of resistor R22 respectively. The other end of resistor R22 and one end of capacitor C8 are grounded together. The other end of capacitor C8 and the other end of resistor R23 are connected to the second terminal of the control module 201.

[0154] One end of resistor R18 is the first terminal of the first acquisition circuit 206, and the other end of capacitor C7 and the other end of resistor R20 together serve as the second terminal of the first acquisition circuit 206.

[0155] One end of resistor R21 serves as the first end of the second acquisition circuit 207, and the other end of capacitor C8 and the other end of resistor R23 together serve as the second end of the second acquisition circuit 207.

[0156] Combination Figure 5 The working principle of the flyback boost converter circuit 20 can be described as follows:

[0157] The microcontroller U4 outputs the first control signal of the second switching module 202 through its pin 1. When the first control signal is low, transistor Q6 is cut off, transistor Q7 is turned on, and subsequently MOSFET Q8 is turned on. The DC power supply 200 forms a circuit with the first primary winding, increasing the current and magnetic flux in the primary winding. The first transformer T1 stores energy, and the voltage induced at the second terminal of the primary winding is negative, causing diode D8 to be cut off. Capacitor C5 outputs the stored energy through diode D6 to discharge a first high-voltage signal to the light source 300.

[0158] When the first control signal is high, transistor Q6 is turned on, transistor Q7 is turned off, and MOSFET Q8 is turned off. The DC power supply 200 and the first primary winding do not form a closed loop. The current and magnetic flux of the first primary winding decrease. The voltage induced at the second end of the first primary winding is a positive voltage. Diode D8 is turned on. The first transformer T1 releases the stored energy to capacitor C5, and can also release it to the subsequent circuits (trigger circuit 30 and direction adjustment circuit 40).

[0159] When the first control signal is low or high, capacitor C5 can output the first high voltage signal to the subsequent circuit, ensuring the normal operation of the subsequent circuit.

[0160] It should be noted that the circuit structure of the flyback boost converter circuit 20 in this application can ensure that the voltage output by port PT3 is the voltage corresponding to the first high voltage signal.

[0161] When the light source 300 is not activated, it needs to be ignited by high voltage. In the traditional trigger circuit 30, a discharge tube is used to achieve ignition, which is a passive ignition. The discharge tube is generally a bidirectional Zener diode, which has a dark effect. In a dark environment, the voltage across its terminals is high, and in a bright environment, the voltage across its terminals is low. The voltage across its terminals varies with the ambient light level, which will cause the voltage across the light source 300 to be unstable.

[0162] Please see Figure 6 , Figure 6This is a schematic diagram of a trigger circuit provided in an embodiment of the present invention, as shown below. Figure 6 As shown, the trigger circuit 30 includes a second transformer 301, a first energy storage circuit 302, and a first switching circuit 303.

[0163] The second transformer 301 includes a second primary winding and a second secondary winding that are coupled together.

[0164] The first end of the first energy storage circuit 302 is connected to port PT3 for receiving a first high voltage signal. The second end of the first energy storage circuit 302 is connected to the first end of the second primary winding. The first energy storage circuit 302 is used to store the first high voltage signal output by the flyback boost converter 20 and to provide a discharge voltage to the second primary winding based on the first high voltage signal.

[0165] The first terminal of the first switching circuit 303 is connected to port PT5 for receiving a first drive signal. The second terminal of the first switching circuit 303 is connected to the second terminal of the second primary winding. The first switching circuit 303 is used to operate in the on state according to the first drive signal.

[0166] The first end of the second winding is connected to the second end of the light source 300. The first end of the light source 300 is directly grounded or grounded through the fourth end of the direction adjustment circuit 40 and the fifth end of the direction adjustment circuit 40. The fifth end of the direction adjustment circuit 40 is grounded and connected to the fifth end of the direction adjustment circuit 40. The second end of the second winding is connected to port PT7 and is connected to the second end of the flyback boost converter circuit 20 through the third end and the first end of the direction adjustment circuit 40. The third end and the first end of the direction adjustment circuit 40 are connected, allowing the second end of the second winding to receive a first high-voltage signal. The second transformer 301 is used to convert the discharge voltage into a second high-voltage signal to ignite the light source 300 when the first switching circuit 303 is in the conducting state.

[0167] The first end of the first energy storage circuit 302 serves as the second end of the trigger circuit, the first end of the first switching circuit 303 serves as the first end of the trigger circuit, the first end of the second stage winding serves as the fourth end of the trigger circuit, and the second end of the second stage winding serves as the third end of the trigger circuit.

[0168] When the flyback boost converter 20 outputs the first high voltage signal, the first high voltage signal is stored by the first energy storage circuit 302.

[0169] When high-voltage ignition of the light source 300 is required, the control module 201 outputs a first drive signal through port PT5, driving the first switching circuit 303 to be in the conducting state, so that the first energy storage circuit 302, the second primary winding, and the first switching circuit 303 form a closed loop. The electrical energy stored in the first energy storage circuit 302 is discharged through the second primary winding of the second transformer 301 and the first switching circuit 303, providing a discharge voltage to the second primary winding. This causes the second primary winding to couple the discharge voltage to the second primary winding, forming a second high-voltage signal at the second primary winding. The voltage of the second high-voltage signal is the ignition voltage. Under the action of the second high-voltage signal, the metal halide of the light source 300 breaks down and enters arc discharge. After successful ignition, the control module 201 stops driving the first switching circuit 303, and the first switching circuit 303 is in the cut-off state, causing the trigger circuit 30 to exit the ignition process, thus completing the ignition process of the light source 300.

[0170] In this embodiment of the invention, the control module 201 controls the ignition process of the light source 300 by controlling the operating state of the first switching circuit 303. When the first switching circuit 303 is in the conducting state, the voltage across its terminals is stable and unaffected by ambient light. Therefore, the voltage at the second primary winding of the second transformer 301 is stable, leading to a stable second high-voltage signal at the secondary winding, and consequently, a stable voltage across the light source 300. Compared to the traditional trigger circuit 30, the trigger circuit 30 in this embodiment of the invention ensures stable ignition of the light source 300, increasing the probability of successful ignition.

[0171] Please see Figure 7 , Figure 7 This is a schematic diagram of a trigger circuit provided in an embodiment of the present invention, as shown below. Figure 7 As shown, the first energy storage circuit 302 includes resistors R24, R25, and R26, and capacitor C9. In this embodiment of the invention, the second transformer 301 is represented by the ignition transformer T2.

[0172] One end of resistor R24 ​​is connected to port PT3. The other end of resistor R24 ​​is connected to one end of resistor R25, one end of capacitor C9, and the first end of the second primary winding. The other end of resistor R25 is connected to one end of resistor R26. The other end of resistor R26 and the other end of capacitor C9 are grounded together.

[0173] One end of resistor R24 ​​serves as the first terminal of the first energy storage circuit 302, and one end of resistor R25 and one end of capacitor C9 serve as the second terminal of the first energy storage circuit 302.

[0174] like Figure 7As shown, the first switching circuit 303 includes a MOSFET Q9, the gate of which is connected to port PT5, the source of which is grounded, and the drain of which is connected to the second end of the second primary winding.

[0175] The drain of MOSFET Q9 serves as the second terminal of the first switching circuit 303, and the gate of MOSFET Q9 serves as the first terminal of the first switching circuit 303. The conducting state of the first switching circuit 303 refers to the MOSFET Q9 being turned on.

[0176] In this embodiment of the invention, capacitor C9 can be a 474J680V type, MOSFET Q9 is an NMOS transistor, and the number of turns in the secondary winding of ignition transformer T2 is relatively large compared to the number of turns in the secondary primary winding to obtain a higher voltage second high-voltage signal. Resistors R25 and R26 are discharge resistors.

[0177] Combination Figure 7 The working principle of the trigger circuit 30 is described as follows:

[0178] When the flyback boost converter circuit 20 outputs the first high voltage signal, the voltage of the first high voltage signal is 400VDC. The first high voltage signal charges the capacitor C9 through the resistor R24, and the capacitor C9 stores electrical energy.

[0179] When the light source 300 needs to be ignited under high voltage, the control module 201 outputs a first drive signal through port PT5. The first drive signal is a high-level signal. The high-level signal acts on the gate of the MOSFET Q9, causing the MOSFET Q9 to conduct. At this time, the electrical energy stored in the capacitor C9 is discharged to ground through the second primary winding of the ignition transformer T2 and the source and drain of the MOSFET Q9, providing a discharge voltage for the second primary winding.

[0180] The discharge voltage is coupled to the second primary winding via the second secondary winding, generating a second high-voltage signal at the second secondary winding. The voltage of the second high-voltage signal is 23KV. The second high-voltage signal serves as the ignition high voltage, breaking down the metal halide of the light source 300, causing the light source 300 to enter arc discharge.

[0181] After successful ignition, the voltage across the light source 300 drops rapidly to between 17V and 28V. At this time, the control module 201 detects the current of the light source 300 and stops outputting the first drive signal, causing the MOSFET Q9 to be turned off and the trigger circuit 30 to exit the ignition process, thus completing the ignition process of the light source 300.

[0182] When the light source 300 is working normally, it can be directly driven by a DC signal, for example, by directly applying a first high-voltage signal to both ends of the light source 300. It can also be driven by an AC signal, for example, by alternately applying the first high-voltage signal to both ends of the light source 300. The AC signal can make the two electrodes of the light source 300 work in an AC state, thereby extending the service life of the lamp electrodes and ensuring the working life of the lamp.

[0183] Specifically, please refer to Figure 8 , Figure 8 This is a schematic diagram of a direction adjustment circuit provided in an embodiment of the present invention, as shown below. Figure 8 As shown, the direction adjustment circuit 40 includes an H-bridge circuit 401, a second switch circuit 402, and a third switch circuit 403.

[0184] The first terminal of the H-bridge circuit 401 is connected to the first terminal of the second switching circuit 402. The second terminal of the H-bridge circuit 401 is connected to port PT3. The third terminal of the H-bridge circuit 401 is connected to both port PT7 and the third terminal of the second switching circuit 402. The fourth terminal of the H-bridge circuit 401 is connected to the second terminal of the second switching circuit 402. The fifth terminal of the H-bridge circuit 401 is grounded. The sixth terminal of the H-bridge circuit 401 is connected to the first terminal of the third switching circuit 403. The seventh terminal of the H-bridge circuit 401 is connected to both the second terminal of the third switching circuit 403 and the first terminal of the light source 300. The eighth terminal of the H-bridge circuit 401 is connected to the third terminal of the third switching circuit 403. The ninth terminal of the H-bridge circuit 401 is connected to the sixth terminal of the flyback boost converter circuit 20. The second terminal of the light source 300 is connected to the fourth terminal of the trigger circuit 30. The sixth terminal of the flyback boost converter circuit 20 is connected to the first or second terminal of the light source 300 through the ninth terminal of the H-bridge circuit 401.

[0185] The second terminal of the second switching circuit 402 is also connected to the fourth terminal of the third switching circuit 403. The fourth terminal of the second switching circuit 402 is connected to port PT4 and is used to receive a second driving signal. The second driving signal is a periodic signal, and one cycle of the second driving signal includes a first level signal and a second level signal.

[0186] The second switching circuit 402 and the third switching circuit 403 are configured to be in a first conducting state when the second driving signal is at a first level signal, thereby controlling the connection of the second and third terminals of the H-bridge circuit 401, and the connection of the fifth and seventh terminals of the H-bridge circuit 401. The H-bridge circuit 401 applies the first high-voltage signal to the second terminal of the light source 300.

[0187] The second switching circuit 402 and the third switching circuit 403 are further configured to be in a second conducting state when the second driving signal is at a second level signal, so as to control the connection of the second terminal and the seventh terminal of the H-bridge circuit 401, and the connection of the fifth terminal and the third terminal of the H-bridge circuit 401. The H-bridge circuit 401 applies the first high-voltage signal to the first terminal of the light source 300.

[0188] The second terminal of the H-bridge circuit 401 serves as the first terminal of the direction adjustment circuit 40, the fourth terminal of the second switch circuit 402 serves as the second terminal of the direction adjustment circuit 40, the third terminal of the H-bridge circuit 401 serves as the third terminal of the direction adjustment circuit 40, the seventh terminal of the H-bridge circuit 401 serves as the fourth terminal of the direction adjustment circuit 40, the fifth terminal of the H-bridge circuit 401 serves as the fifth terminal of the direction adjustment circuit 40, and the ninth terminal of the H-bridge circuit 401 serves as the sixth terminal of the direction adjustment circuit 40.

[0189] Specifically, please refer to the following: Figure 7 The H-bridge circuit 401 includes: MOSFET Q10, MOSFET Q11, MOSFET Q12 and MOSFET Q13.

[0190] The gate of MOSFET Q10 is connected to the first terminal of the second switching circuit 402. The drain of MOSFET Q10 is connected to the second terminal of the flyback boost converter circuit 20 and the drain of MOSFET Q12, which are connected together to port PT3. The source of MOSFET Q10 is connected to the third terminal of the trigger circuit 30, the third terminal of the second switching circuit 402, and the drain of MOSFET Q11. The gate of MOSFET Q11 is connected to the second terminal of the second switching circuit 402. The source of MOSFET Q11 and the source of MOSFET Q13 are grounded together. The gate of MOSFET Q12 is connected to the first terminal of the third switching circuit 403. The source of MOSFET Q12 is connected to the second terminal of the third switching circuit 403, the first terminal of the light source 300, and the drain of MOSFET Q13. The gate of MOSFET Q13 is connected to the third terminal of the third switching circuit 403.

[0191] like Figure 7 As shown, the second switching circuit 402 includes transistor Q14, transistor Q15, and MOSFET Q16, and the third switching circuit 403 includes transistor Q17, transistor Q18, and MOSFET Q19.

[0192] The base of transistor Q14 is connected to the fourth terminal of the flyback boost converter circuit 20 and the base of transistor Q15, respectively, and is connected to port PT4. The emitter of transistor Q14 is grounded, the collector of transistor Q14 is connected to the gate of MOSFET Q16, the source of MOSFET Q16 is grounded, the drain of MOSFET Q16 is connected to the gate of MOSFET Q10, and the collector of transistor Q14 is also connected to the first power supply voltage.

[0193] The emitter of transistor Q15 is grounded. The collector of transistor Q15 is connected to the gate of MOSFET Q11, the base of transistor Q17, and the base of transistor Q18, respectively. The emitter of transistor Q17 is grounded. The collector of transistor Q17 is connected to the gate of MOSFET Q13. The emitter of transistor Q18 is grounded. The collector of transistor Q18 is connected to the gate of MOSFET Q19. The source of MOSFET Q19 is grounded. The drain of MOSFET Q19 is connected to the gate of MOSFET Q12. The collectors of transistors Q15, Q17, and Q18 are also connected to a first power supply voltage.

[0194] In this embodiment of the invention, transistors Q14, Q15, Q17, and Q18 are all NPN transistors, and MOSFETs Q10 to Q19 are all NMOS transistors.

[0195] In this embodiment of the invention, the H-bridge circuit 401 further includes a resistor R27, and the third acquisition circuit 208 includes a resistor R28 and a capacitor C10. One end of the resistor R27 is connected to one end of the resistor R28, the source of the MOSFET Q10, and the source of the MOSFET Q11, respectively. The other end of the resistor R27 is grounded. The other end of the resistor R28 is connected to one end of the capacitor C10 and the sixth terminal of the flyback boost converter circuit 20 through port PT6, respectively. The other end of the capacitor C10 is grounded.

[0196] The flyback boost converter circuit 20 obtains the voltage across resistor R28 through port PT6 to obtain the current of light source 300, thereby sampling the current of light source 300. Resistor R28 and capacitor C10 constitute a filter circuit to filter out sharp signals in the current of light source 300, thereby protecting the sixth terminal of flyback boost converter circuit 20.

[0197] In some embodiments, the direction adjustment circuit 40 may also include diodes as needed to prevent power supply crosstalk, and Zener diodes to protect the gates of the corresponding MOSFETs. MOSFETs Q16 and Q19 can also improve the floating drive problem of the corresponding MOSFETs.

[0198] Specifically, the second switching circuit 402 also includes a diode D6, a Zener diode ZD4, a capacitor C11, a resistor R29, and a resistor R30. The anode of the diode D6 is connected to one end of the resistor R29, and the other end of the resistor R29 is connected to the collector of the transistor Q15 and the gate of the MOSFET Q11. The cathode of the diode D6 is connected to one end of the resistor R30 and one end of the capacitor C11, and the other end of the resistor R30 is connected to the drain of the MOSFET Q16, the gate of the MOSFET Q10, and the cathode of the Zener diode ZD4. The other end of the capacitor C11 is connected to the anode of the Zener diode ZD4, the source of the MOSFET Q10, and the drain of the MOSFET Q11.

[0199] The third switching circuit 403 also includes a diode D7, a Zener diode ZD5, a capacitor C12, a resistor R31, and a resistor R32. The anode of the diode D7 is connected to one end of the resistor R32, and the other end of the resistor R32 is connected to the collector of the transistor Q17 and the gate of the MOSFET Q13. The cathode of the diode D7 is connected to one end of the resistor R31 and one end of the capacitor C12, and the other end of the resistor R31 is connected to the drain of the MOSFET Q19, the gate of the MOSFET Q12, and the cathode of the Zener diode ZD5. The other end of the capacitor C12 is connected to the anode of the Zener diode ZD5, the source of the MOSFET Q12, and the drain of the MOSFET Q13.

[0200] The gate of MOSFET Q10 serves as the first terminal of H-bridge circuit 401, the drain of MOSFET Q10 serves as the second terminal of H-bridge circuit, the source of MOSFET Q10 and the drain of MOSFET Q11 together serve as the third terminal of H-bridge circuit, the gate of MOSFET Q11 serves as the fourth terminal of H-bridge circuit, the source of MOSFET Q11 and the source of MOSFET Q13 together serve as the fifth terminal of H-bridge circuit, the gate of MOSFET Q13 serves as the sixth terminal of H-bridge circuit, the drain of MOSFET Q13 and the source of MOSFET Q12 together serve as the seventh terminal of H-bridge circuit, the gate of MOSFET Q12 serves as the eighth terminal of H-bridge circuit, and the source of MOSFET Q11 and the source of MOSFET Q13 also together serve as the ninth terminal of H-bridge circuit.

[0201] The drain of transistor Q16 and the cathode of Zener diode ZD4 together serve as the first terminal of the second switching circuit 402. The collector of transistor Q15 and the base of transistor Q18 together serve as the second terminal of the second switching circuit 402. The anode of Zener diode ZD4 serves as the third terminal of the second switching circuit 402. The base of transistor Q14 and the base of transistor Q15 together serve as the fourth terminal of the second switching circuit 402.

[0202] The collector of transistor Q17 serves as the first terminal of the third switching circuit 403, the anode of Zener diode ZD5 serves as the second terminal of the third switching circuit 403, the cathode of Zener diode ZD5 and the drain of MOSFET Q19 together serve as the third terminal of the third switching circuit 403, and the base of transistor Q17 and the base of transistor Q18 together serve as the fourth terminal of the third switching circuit 403.

[0203] The first conduction state of the second switching circuit 402 refers to the transistors Q14 and Q15 being turned on and the MOSFET Q16 being turned off. The cutoff state of the second switching circuit 402 refers to the transistors Q14 and Q15 being turned off and the MOSFET Q16 being turned on. The second conduction state of the third switching circuit 403 refers to the transistors Q17 and Q18 being turned off and the MOSFET Q19 being turned on. The cutoff state of the third switching circuit 403 refers to the transistors Q17 and Q18 being turned on and the MOSFET Q19 being turned off.

[0204] Combination Figure 7 The working principle of the direction adjustment circuit 40 can be described as follows:

[0205] The flyback boost converter circuit 20 outputs a second drive signal at its fourth terminal. The second drive signal is a square wave signal. When the square wave signal is at the first level signal, the first level signal is a high level signal, transistors Q14 and Q15 are turned on, and the gate of MOSFET Q16 is at a low level and cut off. The +12V power supply voltage is applied to MOSFET Q10 through diode D6 and resistor R30, causing it to turn on. Meanwhile, MOSFET Q11 is cut off because the turn-on of transistor Q15 pulls down its gate level.

[0206] Transistors Q17 and Q18 are turned off because the conduction of transistor Q15 pulls down their base levels. The 12V supply voltage applies to the gate level of MOSFET Q13, turning it on. The 12V supply voltage applies to the gate of MOSFET Q19, turning it on. This pulls down the gate level of MOSFET Q12, turning it off. Thus, in the H-bridge circuit 401, MOSFETs Q10 and Q13 are turned on, while MOSFETs Q11 and Q12 are turned off.

[0207] When the square wave signal is at the second level, which is a low level signal, transistors Q14 and Q15 are cut off. The 12V supply voltage is applied to the gate of MOSFET Q16, turning it on. The conduction of MOSFET Q16 pulls down the gate level of MOSFET Q10, causing MOSFET Q10 to be cut off. Due to the cutoff of transistor Q15, the 12V supply voltage is applied to the gate of MOSFET Q11, turning it on.

[0208] Because transistor Q15 is cut off, the 12V supply voltage also acts on the bases of transistors Q17 and Q18, causing them to conduct. The conduction of transistor Q17 pulls down the gate of MOSFET Q13, causing it to cut off. The conduction of transistor Q18 pulls down the gate level of MOSFET Q19, causing it to cut off. The cutoff of MOSFET Q19 causes the 12V supply voltage to act on the gate of MOSFET Q12 through diode D7 and resistor 32, turning it on. Thus, in the H-bridge circuit 401, MOSFETs Q10 and Q13 are cut off, while MOSFETs Q11 and Q12 are conducted.

[0209] The high level of the square wave signal can be 5V, and the low level can be 0V. The aforementioned 12V power supply voltage can be provided by the first power supply voltage output by the power switching circuit 10.

[0210] Meanwhile, when the trigger circuit 30 ignites the light source 300 under high voltage, MOSFETs Q10 and Q13 are in the on state, while MOSFETs Q12 and Q11 are in the off state.

[0211] In summary, MOSFETs Q10, Q13, Q11, and Q12 alternately turn on and off, ensuring that the two electrodes of the light source 300 operate in AC mode, thus extending the lifespan of the lamp electrodes and guaranteeing the lamp's operating life. Simultaneously, this direction adjustment circuit controls the MOSFETs in the H-bridge circuit to alternately turn on and off via the second and third switching circuits. If the fourth terminal of the flyback boost converter circuit is a microcontroller's I / O port, the direction adjustment circuit in this invention can achieve AC conversion using only one I / O port to output a square wave signal. Compared to using software control throughout, this saves on I / O port usage and reduces circuit costs.

[0212] Please see Figure 9 , Figure 9 This is a schematic diagram of the structure of one type of light source driving circuit provided in an embodiment of the present invention, such as... Figure 9 As shown, in addition to the power switching circuit, flyback boost converter circuit, trigger circuit and direction adjustment circuit mentioned above, the light source driving circuit also includes a protection circuit 50.

[0213] The input terminal of the protection circuit 50 is connected to the DC power supply 200, and the output terminal is connected to the input terminal of the power switching circuit 10 and the first terminal of the flyback boost converter circuit 20, respectively. The protection circuit 50 is used to prevent the DC power supply 200 from being reverse-connected.

[0214] Specifically, please refer to Figure 10 , Figure 10 This is a schematic diagram of the circuit structure of a light source driving circuit provided in an embodiment of the present invention, as shown below. Figure 10 As shown, the protection circuit 50 includes MOSFET Q20, MOSFET Q21, and Zener diode ZD6. The gates of MOSFET Q20 and Q21 are connected to the cathode of Zener diode ZD6 and the first terminal of DC power supply 200. The source of MOSFET Q20 is connected to the second terminal of DC power supply 200. The drains of MOSFET Q20 and Q21 are connected to each other. The source of MOSFET Q21 is grounded, and the anode of Zener diode ZD6 is grounded.

[0215] When the first terminal of DC power supply 200 is positive and the second terminal is negative, Zener diode ZD6 breaks down in reverse, resulting in a positive regulated voltage of 12V. This regulated voltage acts on the gates of MOSFET Q20 and MOSFET Q21, causing MOSFETs Q20 and Q21 to conduct, allowing DC power supply 200 to output normally. The output terminal of protection circuit 50 then outputs the voltage of DC power supply 200.

[0216] If the DC power supply 200 is in reverse connection, the first terminal of the DC power supply 200 is the negative terminal and the second terminal of the DC power supply 200 is the positive terminal. The cathode of the Zener diode ZD6 receives a reverse voltage, and both MOSFETs Q20 and Q21 are cut off. The two ends of the DC power supply 200 cannot form a loop, thus protecting the subsequent circuits.

[0217] The protection circuit 50 uses two MOSFETs to prevent reverse power connection, which can prevent the MOSFETs from failing to turn off, improve circuit reliability, and thus improve circuit safety.

[0218] The other parts of the light source driving circuit in this embodiment of the invention operate on the same principle as the power switching circuit, flyback boost converter circuit, trigger circuit and direction adjustment circuit described above, and will not be repeated here.

[0219] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A light source driving circuit, characterized by comprising: The light source driving circuit comprises a trigger circuit and a flyback boost conversion circuit; The flyback boost conversion circuit comprises a control module, a second switch module, a voltage conversion module and a first energy storage module; A first end of the second switch module is used for accessing a first power supply voltage, a second end of the second switch module is connected with a first end of the control module, and a third end of the second switch module is connected with a first end of the voltage conversion module; A second end of the voltage conversion module is connected with a direct current power supply, and a third end of the voltage conversion module is connected with a first end of the first energy storage module; The control module is used for outputting a first control signal to the second switch module; The second switch module is used for signal conversion on the first control signal to obtain a second control signal; The voltage conversion module is used for sequentially boosting and rectifying the direct current power supply according to the second control signal, and storing the processed energy in the first energy storage module; The first energy storage module stores the energy to output a first high-voltage signal at the first end of the first energy storage module; The third end of the voltage conversion module is connected with a second end of the trigger circuit and a third end of the trigger circuit respectively, and a third end of the control module is connected with a first end of the trigger circuit; A sixth end of the control module is connected with a first end or a second end of the light source, and the control module is further used for detecting a current of the light source; A fourth end of the trigger circuit is connected with a second end of the light source, a first end of the light source is grounded, when the current of the light source is less than or equal to a first preset value, the flyback boost conversion circuit is further used for outputting a first driving signal to the trigger circuit, and the trigger circuit is used for converting the first high-voltage signal into a second high-voltage signal according to the first driving signal to ignite the light source.

2. The light source driving circuit according to claim 1, characterized by The light source driving circuit further comprises a direction adjusting circuit; A first end of the direction adjusting circuit is connected with the third end of the voltage conversion module, a second end of the direction adjusting circuit is connected with a fourth end of the control module, a third end of the direction adjusting circuit is connected with the third end of the trigger circuit, a fourth end of the direction adjusting circuit is connected with the first end of the light source, a second end of the light source is connected with the fourth end of the trigger circuit, and a fifth end of the direction adjusting circuit is grounded; when the current of the light source is greater than or equal to a second preset value, the flyback boost conversion circuit is further used for stopping outputting the first driving signal to the trigger circuit and outputting a second driving signal to the direction adjusting circuit, and the direction adjusting circuit is used for alternately acting the first high-voltage signal on two ends of the light source according to the second driving signal to make the light source in an alternating current working state.

3. The light source driving circuit according to claim 1 or 2, characterized by The first energy storage module comprises a resistor R13, a diode D6 and a capacitor C5; One end of the resistor R13 is connected with the third end of the voltage conversion module and a cathode of the diode D6 respectively, the other end of the resistor R13 is connected with an anode of the diode D6 and one end of the capacitor C5 respectively, and the other end of the capacitor C5 is grounded.

4. The light source driving circuit according to claim 1 or 2, characterized by The voltage conversion module comprises a first transformer T1, a MOS tube Q8 and a diode D8, the first transformer T1 comprises a first primary winding and a first secondary winding, a first end of the first primary winding is connected with the direct current power supply, a second end of the first primary winding is connected with a drain of the MOS tube Q8 and a first end of the first secondary winding respectively, a second end of the first secondary winding is connected with an anode of the diode D8, a cathode of the diode D8 is connected with a first end of the first energy storage module respectively; a gate of the MOS tube Q8 is connected with a third end of the second switch module, a source of the MOS tube Q8 is grounded.

5. The light source driving circuit according to claim 4, characterized by The second switch module comprises a resistor R14, a resistor R15, a resistor R16, a triode Q6 and a triode Q7; one end of the resistor R14 is connected with a first end of the control module, the other end of the resistor R14 is connected with a base of the triode Q6 and a base of the triode Q7 respectively, an emitter of the triode Q6 is grounded, a collector of the triode Q6 is connected with a collector of the triode Q7 and one end of the resistor R15 respectively, an emitter of the triode Q7 is connected with the first power supply voltage; the other end of the resistor R15 is connected with one end of the resistor R16 and a gate of the MOS tube Q8 respectively, the other end of the resistor R16 is grounded.

6. The light source driving circuit according to claim 4, wherein The flyback boost conversion circuit further comprises a clamping module; one end of the clamping module is connected with the direct current power supply and a second end of the voltage conversion module respectively, the other end of the clamping module is connected with a fourth end of the voltage conversion module, the clamping module is used for clamping a voltage of the fourth end of the voltage conversion module.

7. The light source driving circuit according to claim 6, characterized by The clamping module comprises a capacitor C6, a diode D7 and a resistor R17; one end of the capacitor C6 is connected with one end of the resistor R17 and a first end of the first primary winding respectively, the other end of the capacitor C6 is connected with the other end of the resistor R17 and a cathode of the diode D7 respectively; an anode of the diode D7 is connected with the fourth end of the voltage conversion module.

8. The light source driving circuit according to claim 1 or 2, characterized by The flyback boost conversion circuit further comprises a first acquisition circuit and a second acquisition circuit; a first end of the first acquisition circuit is used for connecting with the direct current power supply, a second end of the first acquisition circuit is connected with a fifth end of the control module, the first acquisition circuit is used for acquiring a voltage of the direct current power supply; a first end of the second acquisition circuit is connected with a first end of the first energy storage module, a second end of the second acquisition circuit is connected with a second end of the control module, the second acquisition circuit is used for acquiring a voltage of the first end of the first energy storage module.

9. The light source driving circuit according to claim 8, characterized by The first acquisition circuit comprises a resistor R18, a resistor R19, a resistor R20 and a capacitor C7, the second acquisition circuit comprises a resistor R21, a resistor R22, a resistor R23 and a capacitor C8; One end of the resistor R18 is connected with the direct current power supply, the other end of the resistor R18 is connected with one end of the resistor R19 and one end of the resistor R20 respectively, the other end of the resistor R19 is commonly grounded with one end of the capacitor C7, the other end of the capacitor C7 is commonly connected with the other end of the resistor R20 to the fifth end of the control module; One end of the resistor R21 is connected with the first end of the first energy storage module, the other end of the resistor R21 is connected with one end of the resistor R23 and one end of the resistor R22 respectively, the other end of the resistor R22 is commonly grounded with one end of the capacitor C8, the other end of the capacitor C8 is commonly connected with the other end of the resistor R23 to the second end of the control module.

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