Lighting circuit and lighting lamp

Abstract

The lighting circuit comprises a lighting module, the lighting module comprises a plurality of LED lamp beads connected in series and voltage stabilizing diodes, each LED lamp bead is correspondingly provided with one voltage stabilizing diode, the positive electrode of each LED lamp bead is connected with the negative electrode of the corresponding voltage stabilizing diode, and the negative electrode of each LED lamp bead is connected with the positive electrode of the corresponding voltage stabilizing diode. The negative electrode of each LED lamp bead is connected with the positive electrode of the corresponding voltage stabilizing diode. The positive electrode of the LED lamp bead at the initial position in the plurality of LED lamp beads which are sequentially connected in series in the lighting module is connected with the driving module, and the negative electrode of the LED lamp bead at the tail end position in the plurality of LED lamp beads which are sequentially connected in series is connected with the driving module; wherein when one LED lamp bead is in an open circuit, the voltage of the positive electrode of the LED lamp bead in the open circuit is larger than the breakdown voltage of the voltage stabilizing diode. According to the technical scheme, when one LED lamp bead is in an open circuit, other LED lamp beads on the series circuit where the LED lamp bead in the open circuit is located can be normally lightened, and the overall lighting effect is not affected.

Description

Technical Field

[0001] The utility model relates to the technical field of LED lighting, in particular to a lighting circuit and a lighting fixture. Background Art

[0002] Due to the advantages of high luminous efficiency, environmental protection, small volume, easy control and long service life, LED light sources have been widely used in various fields. Among them, when an LED light source is applied, a plurality of LED lamp beads are connected in series and in parallel to form a surface light source.

[0003] At present, when forming a light source with LED lamp beads, a plurality of LED lamp beads are connected in series. Among them, when the light source formed in this way is applied, if one LED lamp bead on the series circuit of the light source is open, all the LED lamp beads on the series circuit where the open LED lamp bead is located will not light up, resulting in a large area of black spots in the light source, thus affecting the lighting effect.

[0004] Therefore, the existing technology still needs to be improved and developed. Summary of the Utility Model

[0005] In view of the above deficiencies of the existing technology, the purpose of the utility model is to provide a lighting circuit and a lighting fixture to solve the problem in the existing technology that when one LED lamp bead on the series circuit of the light source is open, all the LED lamp beads on the series circuit where the open LED lamp bead is located will not light up, resulting in a large area of black spots in the light source, thus affecting the lighting effect.

[0006] The technical solution adopted by the utility model to solve its technical problems is: to provide a lighting circuit, including:

[0007] At least one lighting module, the lighting module includes a plurality of LED lamp beads connected in series in sequence and a voltage stabilizing diode. Among them, a voltage stabilizing diode is correspondingly arranged on each LED lamp bead. The positive electrode of each LED lamp bead is connected to the negative electrode of the correspondingly arranged voltage stabilizing diode, and the negative electrode of each LED lamp bead is connected to the positive electrode of the corresponding voltage stabilizing diode;

[0008] A driving module for outputting a first voltage to drive the LED lamp beads, the driving module includes a positive output terminal, a negative output terminal, a positive wiring terminal and a negative wiring terminal. The positive electrode of the LED lamp bead at the starting position among the plurality of LED lamp beads connected in series in the lighting module is connected to the positive output terminal, and the negative electrode of the LED lamp bead at the end position among the plurality of LED lamp beads connected in series is connected to the negative output terminal. The negative wiring terminal and the positive wiring terminal are connected to a power supply;

[0009] Among them, when the lighting module is lit, the conduction voltage of the LED lamp bead is less than the breakdown voltage of the zener diode. When an LED lamp bead is open-circuited, the voltage at the positive pole of the open-circuited LED lamp bead is greater than the breakdown voltage of the zener diode.

[0010] In a further setting of the present utility model, a plurality of the lighting modules are provided. The positive poles of the LED lamp beads at the starting positions in the plurality of lighting modules are connected in parallel to the positive output terminal, and the negative poles of the LED lamp beads at the ending positions in the plurality of lighting modules are connected in parallel to the negative output terminal.

[0011] In a further setting of the present utility model, the conduction voltage drop range of the LED lamp bead is between 2.2 - 3V, and the breakdown voltage of the zener diode is greater than 3V.

[0012] In a further setting of the present utility model, the breakdown voltage of the zener diode is 3.3V.

[0013] In a further setting of the present utility model, the driving module is a DC - DC constant voltage output driving circuit. The positive voltage input terminal of the DC - DC constant voltage output driving circuit is the positive wiring terminal of the driving module, the negative voltage input terminal of the DC - DC constant voltage output driving circuit is the negative wiring terminal of the driving module, the positive output terminal of the DC - DC constant voltage output driving circuit is the positive output terminal of the driving module, and the negative output terminal of the DC - DC constant voltage output driving circuit is the negative output terminal of the driving module;

[0014] The lighting circuit further includes: a power supply for outputting a power supply voltage to the driving module, and the power supply is connected to the positive voltage input terminal and the negative voltage input terminal of the DC - DC constant voltage output driving circuit.

[0015] In a further setting of the present utility model, the driving module is an AC - DC constant voltage output driving circuit. The positive voltage input terminal of the AC - DC constant voltage output driving circuit is the positive wiring terminal of the driving module, the negative voltage input terminal of the AC - DC constant voltage output driving circuit is the negative wiring terminal of the driving module, the positive output terminal of the AC - DC constant voltage output driving circuit is the positive output terminal of the driving module, and the negative output terminal of the AC - DC constant voltage output driving circuit is the negative output terminal of the driving module;

[0016] Among them, the positive voltage input terminal and the negative voltage input terminal of the AC - DC constant voltage output driving circuit are connected to the power supply.

[0017] A further arrangement of the present utility model is that the input voltage range of the constant voltage output driving circuit of the AC-DC is alternating current of 220 - 240V.

[0018] The present utility model also provides a lighting fixture, comprising: a housing and the lighting circuit as described above, wherein the lighting circuit is arranged in the housing.

[0019] Advantages of the present utility model:

[0020] The present utility model discloses a lighting circuit and a lighting fixture, comprising: at least one lighting module, the lighting module includes a plurality of LED lamp beads connected in series in sequence and a voltage stabilizing diode, wherein a voltage stabilizing diode is correspondingly arranged on each LED lamp bead, the positive electrode of each LED lamp bead is connected to the negative electrode of the correspondingly arranged voltage stabilizing diode, and the negative electrode of each LED lamp bead is connected to the positive electrode of the corresponding voltage stabilizing diode; a driving module for outputting a first voltage to drive the LED lamp beads, the driving module includes a positive output terminal and a negative output terminal, the positive electrode of the LED lamp bead at the starting position among the plurality of LED lamp beads connected in series in sequence in the lighting module is connected to the positive output terminal, and the negative electrode of the LED lamp bead at the end position among the plurality of LED lamp beads connected in series in sequence is connected to the negative output terminal; wherein, when the lighting module is lit, the conduction voltage of the LED lamp bead is less than the breakdown voltage of the voltage stabilizing diode, and when an LED lamp bead is open-circuited, the voltage of the positive electrode of the open-circuited LED lamp bead is greater than the breakdown voltage of the voltage stabilizing diode. In the technical solution of the present utility model, when the lighting module is lit, the conduction voltage of the LED lamp bead is less than the breakdown voltage of the voltage stabilizing diode. At this time, the LED lamp bead can work normally and the voltage stabilizing diode is not broken down. When an LED lamp bead is open-circuited, since the voltage of the positive electrode of the open-circuited LED lamp bead is greater than the breakdown voltage of the voltage stabilizing diode, the voltage stabilizing diode corresponding to the open-circuited LED lamp bead is broken down and conducts. Therefore, when an LED lamp bead is open-circuited, other LED lamp beads on the series circuit where the open-circuited LED lamp bead is located can be normally lit, without affecting the overall lighting effect. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required to be used in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0022] Figure 1 It is the circuit structure diagram of the lighting circuit of the present utility model.

[0023] Figure 2 It is the lighting circuit diagram in the prior art.

[0024] Figure 3 It is the specific circuit diagram of the constant voltage output drive circuit of AC - DC in an embodiment.

[0025] Each mark in the attached drawings: 10, drive module; 101, positive output terminal; 102, negative output terminal; 103, positive connection terminal; 104, negative connection terminal; 20, lighting module; 201, LED lamp bead; 202, zener diode; 30, power supply. Specific embodiments

[0026] For a clearer understanding of the technical features, objectives, and effects of the present utility model, the specific embodiments of the present utility model will now be described in detail with reference to the attached drawings. In the following description, it should be understood that the orientation or positional relationships indicated by "front", "rear", "upper", "lower", "left", "right", "longitudinal", "transverse", "vertical", "horizontal", "top", "bottom", "inner", "outer", "head", "tail", etc. are based on the orientation or positional relationships shown in the attached drawings, with a specific orientation structure and operation, and are only for facilitating the description of the present technical solution, rather than indicating that the indicated device or element must have a specific orientation, and thus should not be construed as a limitation to the present utility model.

[0027] Due to the advantages of high luminous efficiency, environmental friendliness, small size, easy control, and long lifespan, LED light sources have been widely used in various fields. Among them, when LED light sources are applied, several LED lamp beads are connected in series and in parallel to form a surface light source.

[0028] As Figure 2 shown, it is a surface light source composed of several LED lamp beads. Although LED lamp beads theoretically have a very long lifespan, greater than 100,000 hours, in actual application processes, due to the influence of various factors, such as the influence of the ripple output by the drive power supply, the influence of the heat dissipation conditions of the light source, the overload of the working current, and other factors in the application environment, LED lamp beads will inevitably be damaged during use (the damage of LED lamp beads often shows as an open circuit).

[0029] In Figure 2 when the surface light source shown is applied, if an LED lamp bead in a series circuit is open, then all the LED lamp beads in the series circuit where the open LED lamp bead is located will not light up. In current light sources, if an LED lamp bead in a series circuit is open, it will cause all the LED lamp beads in the series circuit where the open LED lamp bead is located not to light up, thereby resulting in a large area of black spots in the light source, and thus the lighting effect is affected.

[0030] Based on the above problems, the present utility model provides an illumination circuit, as Figure 1 shown. The illumination circuit may include at least one illumination module 20 and a driving module 10.

[0031] The illumination module 20 may include a plurality of LED lamp beads 201 connected in series in sequence and a voltage stabilizing diode 202. Among them, a voltage stabilizing diode 202 is correspondingly arranged on each LED lamp bead 201. The positive electrode of each LED lamp bead 201 is connected to the negative electrode of the correspondingly arranged voltage stabilizing diode 202, and the negative electrode of each LED lamp bead 201 is connected to the positive electrode of the corresponding voltage stabilizing diode 202.

[0032] The driving module 10 is used to output a first voltage to drive the LED lamp beads 201. The driving module 10 may include a positive output terminal 101, a negative output terminal 102, a positive connection terminal 103, and a negative connection terminal 104. The positive electrode of the LED lamp bead 201 at the starting position among the plurality of LED lamp beads 201 connected in series in sequence in the illumination module 20 is connected to the positive output terminal 101, and the negative electrode of the LED lamp bead 201 at the end position among the plurality of LED lamp beads 201 connected in series in sequence is connected to the negative output terminal 102. The positive connection terminal 103 and the negative connection terminal 104 are connected to the power supply 30. Among them, when the illumination module 20 is lit, the conduction voltage of the LED lamp bead 201 is less than the breakdown voltage of the voltage stabilizing diode 202. When an LED lamp bead 201 is open-circuited, the voltage of the positive electrode of the open-circuited LED lamp bead 201 is greater than the breakdown voltage of the voltage stabilizing diode 202.

[0033] Specifically, as Figure 1 shown, when a plurality of LED lamp beads 201 are connected in series in sequence, the negative electrode of the LED lamp bead 201 at the previous position among the plurality of LED lamp beads 201 is connected to the positive electrode of the LED lamp bead 201 at the next adjacent position. Among them, the previous position refers to the position closer to the starting position among two adjacent positions when installing the LED lamp bead 201, and the next position refers to the position farther from the starting position among two adjacent positions after installing the LED lamp bead 201. When connected to the power supply 30, the positive connection terminal 103 of the driving module 10 is connected to the positive electrode of the power supply 30, and the negative connection terminal 104 of the driving module 10 is connected to the negative electrode of the power supply 30.

[0034] Here, it should be noted that the starting position refers to the first position among a plurality of LED lamp beads 201 connected in series in sequence, and the end position refers to the last position among a plurality of LED lamp beads 201 connected in series in sequence.

[0035] Among them, when a plurality of LED lamp beads 201 are arranged, they can be arranged on a flexible printed circuit board.

[0036] In this embodiment, when the lighting module 20 is lit, the conduction voltage of the LED lamp bead 201 is less than the breakdown voltage of the zener diode 202. At this time, the LED lamp bead 201 can work normally and the zener diode 202 is not broken down. When an LED lamp bead 201 is open-circuited, since the voltage at the positive electrode of the open-circuited LED lamp bead 201 is greater than the breakdown voltage of the zener diode 202, the zener diode 202 corresponding to the open-circuited LED lamp bead 201 is broken down and conducts. Therefore, when an LED lamp bead 201 is open-circuited, the other LED lamp beads 201 on the series circuit where the open-circuited LED lamp bead 201 is located can be normally lit, without affecting the overall lighting effect.

[0037] In some embodiments, as Figure 1 shown, the lighting module 20 may be provided with several. The positive electrodes of the LED lamp beads 201 at the starting positions in the several lighting modules 20 are connected in parallel to the positive electrode output terminal 101, and the negative electrodes of the LED lamp beads 201 at the end positions in the several lighting modules 20 are connected in parallel to the negative electrode output terminal 102.

[0038] When the lighting module 20 is set, it can be set to six, eight, ten, etc. Among them, the several lighting modules 20 form a surface light source. Those skilled in the art can determine the number of the lighting modules 20 according to the actual requirements of the surface light source, and no excessive limitation is made here.

[0039] In this embodiment, when an LED lamp bead 201 in the lighting module 20 is open-circuited, the zener diode 202 corresponding to the open-circuited LED lamp bead 201 is broken down. At this time, the broken-down zener diode 202 is in a conducting state. Therefore, in this lighting module 20, only the open-circuited LED lamp bead 201 is not lit, and the remaining LED lamp beads 201 on the series circuit where the LED lamp bead 201 is located can be normally lit. Therefore, there will be no large-area black spots in the surface light source, and the lighting effect is not affected.

[0040] In some embodiments, the conduction voltage drop range of the LED lamp bead 201 is between 2.2 - 3V, and the breakdown voltage of the zener diode 202 is greater than 3V.

[0041] In this embodiment, the breakdown voltage of the zener diode 202 is higher than the conduction voltage of the LED lamp bead 201. Therefore, when the LED lamp bead 201 is normally conducting, the zener diode 202 does not work and is in a cut-off state, avoiding the problem that the zener diode 202 shares the current on the LED lamp bead 201 and affects the brightness of the LED lamp bead 201.

[0042] In a specific embodiment, the breakdown voltage of the zener diode 202 can be 3.3V. The breakdown voltage of the commonly used zener diode 202 is 3.3V. Therefore, when using the zener diode 202 with a breakdown voltage of 3.3V, the cost is low (when designing a zener diode with a special breakdown voltage, its particularity will lead to a high cost).

[0043] In some embodiments, the driving module 10 can be a DC-DC constant voltage output driving circuit. The positive voltage input terminal of the DC-DC constant voltage output driving circuit is the positive connection terminal 103 of the driving module 10, the negative voltage input terminal of the DC-DC constant voltage output driving circuit is the negative connection terminal 104 of the driving module 10, the positive output terminal of the DC-DC constant voltage output driving circuit is the positive output terminal 101 of the driving module 10, and the negative output terminal of the DC-DC constant voltage output driving circuit is the negative output terminal 102 of the driving module 10.

[0044] The lighting circuit further includes a power supply 30 for supplying a power supply voltage to the driving module. The power supply 30 is connected to the positive voltage input terminal and the negative voltage input terminal of the DC-DC constant voltage output driving circuit.

[0045] In this embodiment, when the driving module 10 is a DC-DC (direct current - direct current) constant voltage output driving circuit, a power supply 30 that outputs direct current can be designed in this lighting circuit. In this way, when this lighting circuit is in use, there is no need to separately match a power supply, making it more convenient to use.

[0046] Specifically, the DC-DC constant voltage output driving circuit can adopt the architecture of a flyback switching circuit, and a circuit built with the FAN6300 chip as the core device.

[0047] Of course, the DC-DC constant voltage output driving circuit can also be a circuit with other structures. When building the DC-DC constant voltage output driving circuit, it is necessary to refer to the output voltage of the power supply 30 and the output voltage of the DC-DC constant voltage output driving circuit. For example, if the output of the power supply 30 is a 36V DC voltage and the output voltage of the DC-DC constant voltage output driving circuit is a 24V DC voltage, then the built DC-DC constant voltage output driving circuit needs to convert the 36V DC voltage into a 24V DC voltage; another example, if the output of the power supply 30 is a 72V DC voltage and the output voltage of the DC-DC constant voltage output driving circuit is a 36V DC voltage, then the built DC-DC constant voltage output driving circuit needs to convert the 72V DC voltage into a 36V DC voltage; those skilled in the art can build it according to the actual situation and will not be elaborated here too much.

[0048] In some embodiments, the driving module 10 may also be a constant-voltage output driving module for AC-DC (alternating current-direct current). The positive voltage input terminal of the AC-DC constant-voltage output driving module is the positive wiring terminal 103 of the driving module 10, the negative voltage input terminal of the AC-DC constant-voltage output driving module is the negative wiring terminal 104 of the driving module 10, the positive output terminal of the AC-DC constant-voltage output driving module is the positive output terminal 101 of the driving module 10, and the negative output terminal of the AC-DC constant-voltage output driving module is the negative output terminal 102 of the driving module 10. Among them, the positive voltage input terminal of the AC-DC constant-voltage output driving module and the negative voltage input terminal of the AC-DC constant-voltage output driving module are connected to the power supply 30.

[0049] In this embodiment, when the driving module 10 is an AC-DC constant-voltage output driving circuit, the AC-DC constant-voltage output driving circuit can be powered by an external AC source. Similarly, the AC-DC constant-voltage output driving circuit can adopt the architecture of a flyback switching circuit and is a circuit built with the FAN6300 chip as the core device.

[0050] It can be seen that the driving module 10 can be a DC-DC constant-voltage output driving circuit or an AC-DC constant-voltage output driving circuit, making the lighting circuit more flexible to use. That is, those skilled in the art can determine the specific situation of the driving module according to the specific situation of the power supply 30.

[0051] In some embodiments, the output voltage of the power supply 30 is alternating current with a range of 220 - 240V.

[0052] In this embodiment, when building the AC-DC constant-voltage output driving circuit, it can be built into an AC-DC constant-voltage output driving circuit with an input voltage range of 220 - 240V alternating current and an output voltage of constant 36V. For example, Figure 3 Shown is the specific circuit structure of an AC-DC constant-voltage output driving circuit with an input voltage range of 220 - 240V alternating current and an output voltage of constant 36V. Among them, the core device is the FAN6300 chip.

[0053] In some embodiments, as Figure 1 Shown, the lighting circuit further includes a power supply 30. The power supply 30 is connected to the driving module 10, and the power supply 30 is used to output a supply voltage to the driving module 10 so that the driving module 10 can output a first voltage to the lighting module 20 to drive the LED lamp beads 201.

[0054] In this embodiment, when setting the power supply 30, it needs to be specifically set in combination with the supply voltage of the driving module 10. Those skilled in the art can determine the output voltage of the power supply 30 according to actual needs.

[0055] Of course, when the lighting circuit is in use, an external power supply 30 can also be adopted to supply power to the driving module 10.

[0056] In some embodiments, the present invention further provides a lighting fixture, which may include a housing and the above-mentioned lighting circuit, wherein the lighting circuit is disposed in the housing.

[0057] Wherein, the lighting circuit may include at least one lighting module 20 and a driving module 10.

[0058] The lighting module 20 may include a plurality of LED lamp beads 201 connected in series in sequence and a voltage stabilizing diode 202. Wherein, a voltage stabilizing diode 202 is correspondingly disposed on each LED lamp bead 201. The positive electrode of each LED lamp bead 201 is connected to the negative electrode of the correspondingly disposed voltage stabilizing diode 202, and the negative electrode of each LED lamp bead 201 is connected to the positive electrode of the corresponding voltage stabilizing diode 202.

[0059] The driving module 10 is used to output a first voltage to drive the LED lamp beads 201. The driving module 10 may include a positive output terminal 101, a negative output terminal 102, a positive wiring terminal 103 and a negative wiring terminal 104. The positive electrode of the LED lamp bead 201 at the starting position among the plurality of LED lamp beads 201 connected in series in sequence in the lighting module 20 is connected to the positive output terminal 101, and the negative electrode of the LED lamp bead 201 at the end position among the plurality of LED lamp beads 201 connected in series in sequence is connected to the negative output terminal 102. The negative wiring terminal 104 and the positive wiring terminal 103 are connected to the power supply 30. Wherein, when the lighting module 20 is lit, the conduction voltage of the LED lamp bead 201 is less than the breakdown voltage of the voltage stabilizing diode 202. When an LED lamp bead 201 is open-circuited, the voltage of the positive electrode of the open-circuited LED lamp bead 201 is greater than the breakdown voltage of the voltage stabilizing diode 202.

[0060] In this embodiment, when the lighting module 20 is lit, the conduction voltage of the LED lamp bead 201 is less than the breakdown voltage of the voltage stabilizing diode 202. At this time, the LED lamp bead 201 can work normally and the voltage stabilizing diode 202 is not broken down. When an LED lamp bead 201 is open-circuited, since the voltage of the positive electrode of the open-circuited LED lamp bead 201 is greater than the breakdown voltage of the voltage stabilizing diode 202, the voltage stabilizing diode 202 corresponding to the open-circuited LED lamp bead 201 is broken down and conducted. Therefore, when an LED lamp bead 201 is open-circuited, the other LED lamp beads 201 on the series path where the open-circuited LED lamp bead 201 is located can be normally lit, without affecting the overall lighting effect.

[0061] Here, it should be noted that the description of the above lighting fixture embodiments is similar to that of the above lighting circuit embodiments and has beneficial effects similar to those of the above lighting circuit embodiments. For the technical details not disclosed in the lighting fixture embodiments of this embodiment, please refer to the description of the lighting circuit embodiments of the present utility model for understanding.

[0062] In summary, the present utility model provides a lighting circuit and a lighting fixture, having the following beneficial effects:

[0063] When the lighting module 20 is lit, the conduction voltage of the LED lamp bead 201 is less than the breakdown voltage of the voltage stabilizing diode 202. At this time, the LED lamp bead 201 can work normally and the voltage stabilizing diode 202 is not broken down. When an LED lamp bead 201 is open-circuited, since the voltage at the positive electrode of the open-circuited LED lamp bead 201 is greater than the breakdown voltage of the voltage stabilizing diode 202, the voltage stabilizing diode 202 corresponding to the open-circuited LED lamp bead 201 is broken down and conducts. Therefore, when an LED lamp bead 201 is open-circuited, the other LED lamp beads 201 on the series circuit where the open-circuited LED lamp bead 201 is located can be normally lit, without affecting the overall lighting effect.

[0064] It can be understood that the above embodiments only represent the preferred embodiments of the present utility model, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent of the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, the above technical features can be freely combined, and several deformations and improvements can also be made, all of which fall within the protection scope of the present utility model. Therefore, all equivalent transformations and modifications made to the scope of the claims of the present utility model shall fall within the scope covered by the claims of the present utility model.

Claims

1. An illumination circuit, characterized in that, Comprising: At least one lighting module, the lighting module includes a plurality of LED lamp beads connected in series in sequence and a zener diode, wherein, a zener diode is correspondingly arranged on each LED lamp bead, the positive electrode of each LED lamp bead is connected to the negative electrode of the correspondingly arranged zener diode, and the negative electrode of each LED lamp bead is connected to the positive electrode of the corresponding zener diode; A driving module for outputting a first voltage to drive the LED lamp beads, the driving module includes a positive output terminal, a negative output terminal, a positive connection terminal and a negative connection terminal, the positive electrode of the LED lamp bead at the starting position among the plurality of LED lamp beads connected in series in sequence in the lighting module is connected to the positive output terminal, the negative electrode of the LED lamp bead at the end position among the plurality of LED lamp beads connected in series in sequence is connected to the negative output terminal, and the negative connection terminal and the positive connection terminal are connected to a power supply; Wherein, when the lighting module is lit, the conduction voltage of the LED lamp bead is less than the breakdown voltage of the zener diode, and when an LED lamp bead is open-circuited, the voltage of the positive electrode of the open-circuited LED lamp bead is greater than the breakdown voltage of the zener diode.

2. The lighting circuit according to claim 1, wherein, A plurality of the lighting modules are provided, the positive electrodes of the LED lamp beads at the starting positions in the plurality of lighting modules are connected in parallel to the positive output terminal, and the negative electrodes of the LED lamp beads at the end positions in the plurality of lighting modules are connected in parallel to the negative output terminal.

3. The lighting circuit according to claim 1 or 2, characterized in that, The conduction voltage drop range of the LED lamp bead is between 2.2 - 3V, and the breakdown voltage of the zener diode is greater than 3V.

4. The lighting circuit according to claim 3, wherein, The breakdown voltage of the zener diode is 3.3V.

5. The lighting circuit according to claim 1, wherein, The driving module is a DC - DC constant voltage output driving circuit, the positive voltage input terminal of the DC - DC constant voltage output driving circuit is the positive connection terminal of the driving module, the negative voltage input terminal of the DC - DC constant voltage output driving circuit is the negative connection terminal of the driving module, the positive output terminal of the DC - DC constant voltage output driving circuit is the positive output terminal of the driving module, and the negative output terminal of the DC - DC constant voltage output driving circuit is the negative output terminal of the driving module; The lighting circuit further includes: a power supply for outputting a supply voltage to the driving module, and the power supply is connected to the positive voltage input terminal and the negative voltage input terminal of the DC - DC constant voltage output driving circuit.

6. The lighting circuit according to claim 1, wherein The driving module is an AC - DC constant voltage output driving circuit, the positive voltage input terminal of the AC - DC constant voltage output driving circuit is the positive connection terminal of the driving module, the negative voltage input terminal of the AC - DC constant voltage output driving circuit is the negative connection terminal of the driving module, the positive output terminal of the AC - DC constant voltage output driving circuit is the positive output terminal of the driving module, and the negative output terminal of the AC - DC constant voltage output driving circuit is the negative output terminal of the driving module; Wherein, the positive voltage input terminal of the constant voltage output driving circuit of the AC-DC and the negative voltage input terminal of the constant voltage output driving circuit of the AC-DC are connected to the power supply.

7. The lighting circuit according to claim 6, wherein The input voltage range of the constant voltage output driving circuit of the AC-DC is alternating current of 220-240V.

8. A lighting fixture, characterized in that, Comprising: A housing and the lighting circuit according to any one of claims 1-7, wherein the lighting circuit is arranged in the housing.

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