LED module detection circuit

Abstract

The present invention provides a detection circuit for an LED module. The detection circuit is connected to the rear side of the LED module. The detection circuit includes: a signal detection circuit including an AND gate circuit and a first indicator element arranged in series, the AND gate circuit being connected between the signal input terminal of the LED module and the first indicator element; a power detection circuit including a first power detection circuit for detecting whether the LED module has input voltage and a second power detection circuit for detecting whether the LED module is in an undervoltage state. The first power detection circuit is provided with a second indicator element. When the LED module has no input voltage, the second indicator element emits a second indicator signal. The second power detection circuit is provided with a third indicator element. When the LED module is in an undervoltage state, the third indicator element emits a third indicator signal. The technical solution of the present application can effectively solve the problem of low module maintenance efficiency when the number of modules is large in the related art.

Description

Technical Field

[0001] The present invention relates to the technical field of LED display, and in particular to a detection circuit for an LED module. Background Art

[0002] LED displays typically consist of a display cabinet and multiple display modules mounted on it. During use, the display will wear out, and in most cases, maintenance requires removing the display modules for repair or replacement. In some scenarios, maintenance can only be performed from behind the display due to on-site installation environment constraints. For example, many outdoor display screens require module maintenance from behind, where the modules are removed from the back of the cabinet.

[0003] However, when there are a large number of module boxes, it becomes extremely troublesome for maintenance personnel to select the corresponding module for maintenance based on the display conditions of the module light surface, which makes maintenance efficiency low. Summary of the Invention

[0004] The main purpose of the present invention is to provide a detection circuit for an LED module to solve the problem in the related art that when the number of modules is large, the module maintenance efficiency is low.

[0005] In order to achieve the above-mentioned objectives, the present invention provides a detection circuit for an LED module, which is connected to the rear side of the LED module. The detection circuit includes: a signal detection circuit, including an AND gate circuit and a first indicator element arranged in series, and the AND gate circuit is connected between the signal input terminal of the LED module and the first indicator element. When the input signal of the LED module is abnormal, the first indicator element sends a first indication signal; a power supply detection circuit, including a first power supply detection circuit for detecting whether the LED module has an input voltage and a second power supply detection circuit for detecting whether the LED module is in an undervoltage state. The first power supply detection circuit is provided with a second indicator element. When the LED module has no input voltage, the second indicator element sends a second indication signal. The second power supply detection circuit is provided with a third indicator element. When the LED module is in an undervoltage state, the third indicator element sends a third indication signal.

[0006] Furthermore, the first indicator element is a first light emitting diode, the signal input terminal of the LED module is connected to the input end of the AND gate circuit, the anode of the first light emitting diode is connected to the first power supply, and the cathode of the first light emitting diode is connected to the output end of the AND gate circuit.

[0007] Furthermore, the signal input terminal of the LED module includes a high-level input terminal and a low-level input terminal, the high-level input terminal is connected to the first input terminal of the AND gate circuit, and the low-level input terminal is connected to the second input terminal of the AND gate circuit. The signal detection circuit also includes a NOT gate circuit arranged between the low-level input terminal and the second input terminal.

[0008] Furthermore, the first power detection circuit includes a second power supply, the second indicating element is a second light emitting diode, the anode of the second light emitting diode is connected to the positive electrode of the second power supply, and the cathode of the second light emitting diode is connected to the power supply of the LED module.

[0009] Furthermore, the first power supply detection circuit also includes a charging detection circuit arranged at both ends of the second power supply, the charging detection circuit includes a comparator, the positive pole of the second power supply is connected to the reverse input end of the comparator, and the positive input end of the comparator is connected to the third power supply.

[0010] Furthermore, the charging detection circuit also includes a constant current charging circuit, which includes a constant voltage circuit, a first constant current circuit, a first transistor and a second constant current circuit. The first transistor is a PNP transistor. The first end of the constant voltage circuit is connected to the first end of the first constant current circuit, the second end of the constant voltage circuit is connected to the base of the first transistor, the second end of the first constant current circuit is connected to the emitter of the first transistor, the first end of the second constant current circuit is connected to the collector of the first transistor, and the second end of the second constant current circuit is connected to the second power supply for charging the second power supply.

[0011] Furthermore, the charging detection circuit also includes a second transistor, which is an NPN transistor, the base of the second transistor is connected to the output end of the comparator, the emitter of the second transistor is grounded, and the collector of the second transistor is connected to the base of the first transistor.

[0012] Furthermore, the second power supply detection circuit also includes a step-down circuit, the third indicating element is a third light-emitting diode, the first end of the step-down circuit is connected to the power supply of the LED module, the second end of the step-down circuit is connected to the cathode of the third light-emitting diode, and the anode of the third light-emitting diode is connected to the power supply of the LED module.

[0013] Furthermore, the step-down circuit includes a voltage-stabilizing diode, an amplifying circuit, and a potentiometer connected between the voltage-stabilizing diode and the amplifying circuit, the cathode of the voltage-stabilizing diode is connected to the power supply of the LED module, the anode of the voltage-stabilizing diode is connected to the first fixed end of the potentiometer, the second fixed end of the potentiometer is grounded, the first end of the amplifying circuit is connected to the moving end of the potentiometer, and the second end of the amplifying circuit is connected to the cathode of the third light-emitting diode.

[0014] Furthermore, the amplification circuit includes a third transistor and a fourth transistor, both of which are NPN transistors, the base of the third transistor is connected to the anode of the voltage-stabilizing diode, the collector of the third transistor is connected to the base of the fourth transistor, and the collector of the fourth transistor is connected to the cathode of the third light-emitting diode.

[0015] Using the technical solution of the present invention, a signal detection circuit and a power detection circuit are provided on the rear side of the LED module. The signal detection circuit includes an AND gate circuit and a first indicator element arranged in series. During post-maintenance, maintenance personnel can determine whether the module's input signal is abnormal by directly observing whether the first indicator element emits a first indicator signal. The power detection circuit includes a first power detection circuit for detecting whether the LED module has input voltage and a second power detection circuit for detecting whether the LED module is in an undervoltage state. During maintenance, maintenance personnel can determine whether the LED module has input voltage by directly observing whether the second indicator element emits a second indicator signal, and can determine whether the LED module is undervoltage by directly observing whether the third indicator element emits a third indicator signal. By providing the detection circuit of the present application, during maintenance, there is no need to search for the LED module requiring maintenance based on the display on the LED module's light surface. Instead, the module requiring maintenance can be directly found using the first, second, and third indicator elements, resulting in high efficiency. Furthermore, this solution directly detects the input signal and input power, rather than judging by observing the module's display, resulting in high accuracy. Therefore, the technical solution of the present application can effectively solve the problem of low module maintenance efficiency when the number of modules is large in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0017] Figure 1 A circuit diagram showing an embodiment of a signal detection circuit according to the present invention;

[0018] Figure 2 A circuit diagram showing an embodiment of a power detection circuit according to the present invention; and

[0019] Figure 3 Shown Figure 2 Circuit diagram of the power detection circuit and the charging detection circuit.

[0020] The above drawings include the following reference numerals:

[0021] 10. Signal detection circuit; 11. AND gate circuit; 12. First indicator element; 13. NOT gate circuit; 20. Power supply detection circuit; 21. First power supply detection circuit; 211. Second indicator element; 212. Second power supply; 213. Charging detection circuit; 2131. Comparator; 2132. Constant-current charging circuit; 2133. Constant-voltage circuit; 2134. First constant-current circuit; 2135. First transistor; 2136. Second constant-current circuit; 2137. Second transistor; 22. Second power supply detection circuit; 221. Third indicator element; 222. Buck circuit; 2221. Zener diode; 2222. Amplifier circuit; 2223. Potentiometer; 2224. Third transistor; 2225. Fourth transistor. DETAILED DESCRIPTION

[0022] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0024] Unless otherwise specifically stated, the relative arrangement of the parts and steps, the numerical expressions and the numerical values ​​set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as being merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0025] like Figures 1 to 3As shown, the detection circuit of the LED module of this embodiment is connected to the rear side of the LED module, and the detection circuit includes: a signal detection circuit 10, including an AND gate circuit 11 and a first indicator element 12 arranged in series, the AND gate circuit 11 is connected between the signal input terminal of the LED module and the first indicator element 12, when the input signal of the LED module is abnormal, the first indicator element 12 sends a first indication signal; a power detection circuit 20, including a first power detection circuit 21 for detecting whether the LED module has an input voltage and a second power detection circuit 22 for detecting whether the LED module is in an undervoltage state, the first power detection circuit 21 is provided with a second indicator element 211, when the LED module has no input voltage, the second indicator element 211 sends a second indication signal, the second power detection circuit 22 is provided with a third indicator element 221, when the LED module is in an undervoltage state, the third indicator element 221 sends a third indication signal.

[0026] Using the technical solution of this embodiment, a signal detection circuit 10 and a power detection circuit 20 are installed on the rear side of the LED module. The signal detection circuit 10 includes an AND gate circuit 11 and a first indicator element 12 arranged in series. During post-maintenance, maintenance personnel can determine whether the LED module's input signal is abnormal by directly observing whether the first indicator element 12 emits a first indication signal. The power detection circuit 20 includes a first power detection circuit 21 for detecting whether the LED module has input voltage, and a second power detection circuit 22 for detecting whether the LED module is undervoltage. During maintenance, maintenance personnel can determine whether the LED module has input voltage by directly observing whether the second indicator element 211 emits a second indication signal, and whether the LED module is undervoltage by directly observing whether the third indicator element 221 emits a third indication signal. By installing the detection circuit of this embodiment, maintenance personnel no longer need to rely on the display on the LED module's light panel to locate the LED module requiring maintenance. Instead, they can directly identify the module requiring maintenance using the first indicator element 12, the second indicator element 211, and the third indicator element 221, resulting in high efficiency. Furthermore, this solution directly detects the input signal and input power rather than judging by observing the module's display, which has the advantage of high accuracy. Therefore, the technical solution of this embodiment can effectively solve the problem of low module maintenance efficiency when the number of modules is large in related technologies.

[0027] There are many ways to implement the AND gate circuit, for example, it can be implemented using CMOS logic, NMOS logic, PMOS logic, and diodes. Since the specific implementation method of the AND gate circuit belongs to the conventional technical means in this field, it will not be repeated here.

[0028] like Figure 1As shown, the first indicator element 12 is a first light-emitting diode. The signal input terminal of the LED module is connected to the input end of the AND gate circuit 11, the anode of the first light-emitting diode is connected to the first power supply, and the cathode of the first light-emitting diode is connected to the output end of the AND gate circuit 11. The signal input terminal of the LED module is connected to the input end of the AND gate circuit 11. When there is an abnormality in the signal input of the LED module, the output end of the AND gate circuit 11 is at a low level, causing a potential difference to be generated between the anode and cathode of the first light-emitting diode, causing the first light-emitting diode to turn on and emit light. At this time, the light signal emitted by the first light-emitting diode forms the first indicator signal. Based on this, maintenance personnel can quickly find the LED module with an abnormal input signal from a large number of LED modules.

[0029] like Figure 1 As shown, a resistor R1 is provided between the anode of the first indicator element 12 and the first power supply.

[0030] like Figure 1 As shown, the signal input terminal of the LED module includes a high-level input terminal and a low-level input terminal. The high-level input terminal is connected to the first input terminal of the AND gate circuit 11, and the low-level input terminal is connected to the second input terminal of the AND gate circuit 11. The signal detection circuit 10 also includes a NOT gate circuit 13 disposed between the low-level input terminal and the second input terminal. The NOT gate circuit 13 is disposed between the low-level input terminal and the second input terminal to input a high level to the AND gate circuit 11. Specifically, in this embodiment, the input signals of the LED module include a CLK signal, a LAT signal, an OE signal, a row SDI signal, and a column SDI signal. The CLK signal, LAT signal, row SDI signal, and column SDI signal are input at a high level, and the OE signal is input at a low level. The NOT gate circuit 13 is disposed between the OE signal input terminal and the AND gate circuit 11. When the input level of at least one of the above five input signals is different from the level it should be input (for example, one or more of the CLK signal, LAT signal, row SDI signal and column SDI signal are input at a low level, or the OE signal is input at a high level), it means that there is an abnormality in the input signal. At this time, the output end of the AND gate circuit 11 outputs a low level, causing the first light-emitting diode to turn on and emit light.

[0031] like Figure 2As shown, in this embodiment, the first power detection circuit 21 includes a second power supply 212, the second indicator element 211 is a second light-emitting diode, the anode of the second light-emitting diode is connected to the positive pole of the second power supply 212, and the cathode of the second light-emitting diode is connected to the power supply of the LED module (such as the positive pole of the power supply). When there is no power input to the LED module, there is a potential difference between the anode and cathode of the second light-emitting diode, the second light-emitting diode is turned on and emits light, and the light signal emitted by the second light-emitting diode forms a second indication signal. Based on this, maintenance personnel can quickly find the LED module without power input from a large number of LED modules. Specifically, in this embodiment, the second power supply 212 is a button battery.

[0032] like Figure 2 and Figure 3 As shown, the first power supply detection circuit 21 also includes a charging detection circuit 213 disposed at both ends of the second power supply 212. The charging detection circuit 213 includes a comparator 2131. The positive electrode of the second power supply 212 is connected to the inverting input of the comparator 2131, and the positive input of the comparator 2131 is connected to the third power supply. The charging detection circuit 213 is disposed at both ends of the second power supply 212 and is capable of detecting whether the second power supply 212 is undervoltage. By providing the comparator 2131, the discharge voltage of the second power supply 212 is compared with a predetermined voltage value. When the discharge voltage of the second power supply 212 is lower than the predetermined value, it indicates that the second power supply 212 is undervoltage and can be charged.

[0033] like Figure 2 As shown, the first power detection circuit 21 further includes a resistor R5 disposed between the power supply of the LED module and the negative electrode of the second power supply 212 .

[0034] like Figure 2 and Figure 3As shown, in this embodiment, the charging detection circuit 213 further includes a constant current charging circuit 2132. The constant current charging circuit 2132 includes a constant voltage circuit 2133, a first constant current circuit 2134, a first transistor 2135, and a second constant current circuit 2136. The first transistor 2135 is a PNP transistor. A first end of the constant voltage circuit 2133 is connected to a first end of the first constant current circuit 2134. A second end of the constant voltage circuit 2133 is connected to a base of the first transistor 2135. A second end of the first constant current circuit 2134 is connected to an emitter of the first transistor 2135. A first end of the second constant current circuit 2136 is connected to a collector of the first transistor 2135. A second end of the second constant current circuit 2136 is connected to the second power supply 212 for charging the second power supply 212. When it is detected that the second power supply 212 is in an undervoltage state, the constant current charging circuit 2132 can charge the second power supply 212. Specifically, in this embodiment, a constant voltage circuit 2133 is formed by a diode D1 and a diode D2 connected in series. A resistor R6 is provided in a first constant current circuit 2134 and connected in parallel with the constant voltage circuit 2133. The current in the first constant current circuit 2134 is amplified by a first transistor 2135 and then flows into a second constant current circuit 2136 to charge the second power supply 212. A current-limiting resistor R7 is provided in the second constant current circuit 2136.

[0035] like Figure 2 and Figure 3 As shown, the charging detection circuit 213 further includes a second transistor 2137, which is an NPN transistor. The base of the second transistor 2137 is connected to the output of the comparator 2131, the emitter of the second transistor 2137 is grounded, and the collector of the second transistor 2137 is connected to the base of the first transistor 2135. The comparator 2131 can compare the discharge voltage of the second power supply 212 with a predetermined voltage value. When the discharge voltage of the second power supply 212 is lower than the predetermined value, the comparator 2131 outputs a high level, turning on the second transistor 2137 and, in turn, turning on the first transistor 2135 to charge the second power supply 212. When the discharge voltage of the second power supply 212 is higher than the predetermined value, the comparator 2131 outputs a low level, turning off both the second transistor 2137 and the first transistor 2135.

[0036] like Figure 3 As shown, capacitor C1 can act as a filter; resistors R13, R14, and R15 can act as a voltage divider; resistors R8, R10, and R6 are bias resistors, ensuring that the amplifier circuit has a suitable operating point; resistors R11 and R12 are feedback resistors that can act as a voltage divider. In this embodiment, comparator 2131 is an LM339 chip.

[0037] like Figure 2As shown, the second power supply detection circuit 22 also includes a step-down circuit 222, and the third indicator element 221 is a third light-emitting diode. The first end of the step-down circuit 222 is connected to the power supply of the LED module (such as the positive electrode of the power supply), the second end of the step-down circuit 222 is connected to the cathode of the third light-emitting diode, and the anode of the third light-emitting diode is connected to the power supply of the LED module. The input voltage of the power supply of the LED module is connected to the cathode of the third light-emitting diode after being stepped down by the step-down circuit 222, and the anode of the third light-emitting diode is directly connected to the power supply of the LED module. When the input voltage of the power supply of the LED module is lower than a predetermined value, a potential difference is generated between the anode and cathode of the third light-emitting diode, and the third light-emitting diode is turned on and emits light. At this time, the light signal emitted by the third light-emitting diode forms a third indicator signal. Based on this, maintenance personnel can quickly find the LED module operating in an undervoltage state from a large number of LED modules.

[0038] In this embodiment, the first indicator element 12, the second indicator element 211 and the third indicator element 221 can be light-emitting diodes that can emit light of different colors. By directly observing whether each light-emitting diode is emitting light, it is possible to quickly determine whether there is an abnormality in the signal input and power input of the LED module. By observing the color of the light, it is possible to quickly determine what kind of abnormality exists in the LED module, thereby effectively improving maintenance efficiency.

[0039] In this embodiment, a light-emitting diode is used as the indicator element, which has the advantages of low cost, simple structure, and easy identification. It is understood that in embodiments not shown in the figures, the indicator element can also be other elements capable of providing an indication, such as a miniature LED display or instrument; accordingly, depending on the specific type of indicator element, the indication signal will also take different forms.

[0040] like Figure 2 As shown, the step-down circuit 222 includes a Zener diode 2221, an amplifier circuit 2222, and a potentiometer 2223 connected between the Zener diode 2221 and the amplifier circuit 2222. The cathode of the Zener diode 2221 is connected to the power supply of the LED module, the anode of the Zener diode 2221 is connected to the first fixed terminal of the potentiometer 2223, the second fixed terminal of the potentiometer 2223 is grounded, the first terminal of the amplifier circuit 2222 is connected to the movable terminal of the potentiometer 2223, and the second terminal of the amplifier circuit 2222 is connected to the cathode of the third light-emitting diode. By properly setting the resistance values ​​of resistors R2, R3, R4, and potentiometer 2223, the third light-emitting diode is turned on and emits light when the power supply of the LED module is lower than the predetermined operating voltage.

[0041] like Figure 2As shown, amplifier circuit 2222 includes a third transistor 2224 and a fourth transistor 2225. Both the third transistor 2224 and the fourth transistor 2225 are NPN transistors. The base of the third transistor 2224 is connected to the anode of the Zener diode 2221, the collector of the third transistor 2224 is connected to the base of the fourth transistor 2225, and the collector of the fourth transistor 2225 is connected to the cathode of the third light-emitting diode. Amplification by two transistors can directly amplify DC signals.

[0042] Specifically, in this embodiment, each LED module is correspondingly provided with the above-mentioned detection circuit. Among them, the signal detection circuit 10 in the detection circuit is connected in parallel with the signal circuit of the LED module, and the power detection circuit 20 is connected in parallel with the power supply circuit of the LED module, so as to detect the signal input and power input of the LED module. Preferably, the above-mentioned detection circuit can be set on the hub board of the LED box (an LED display screen is spliced ​​by multiple LED boxes, each LED box includes multiple LED modules and a hub board, and the hub board is located on the rear side of the multiple LED modules). This makes it easy to expose the first indicator element 12, the second indicator element 211 and the third indicator element 221 to the rear side of the box, so that it is easy to observe whether there is any abnormality in the power input and signal input of the corresponding LED module through the above-mentioned indicator elements.

[0043] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0044] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0045] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0046] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A detection circuit for an LED module, characterized in that: The detection circuit is connected to the rear side of the LED module, and the detection circuit includes: A signal detection circuit (10) comprises an AND gate circuit (11) and a first indicator element (12) arranged in series, wherein the AND gate circuit (11) is connected between the signal input terminal of the LED module and the first indicator element (12), and when the input signal of the LED module is abnormal, the first indicator element (12) emits a first indication signal; A power detection circuit (20) comprising a first power detection circuit (21) for detecting whether the LED module has an input voltage and a second power detection circuit (22) for detecting whether the LED module is in an undervoltage state, wherein the first power detection circuit (21) is provided with a second indicator element (211), and when the LED module has no input voltage, the second indicator element (211) emits a second indicator signal, and the second power detection circuit (22) is provided with a third indicator element (221), and when the LED module is in an undervoltage state, the third indicator element (221) emits a third indicator signal; The second power supply detection circuit (22) further includes a step-down circuit (222), the third indicator element (221) is a third light-emitting diode, a first end of the step-down circuit (222) is connected to the power supply of the LED module, a second end of the step-down circuit (222) is connected to the cathode of the third light-emitting diode, and an anode of the third light-emitting diode is connected to the power supply of the LED module; The step-down circuit (222) comprises a voltage-stabilizing diode (2221), an amplifying circuit (2222), and a potentiometer (2223) connected between the voltage-stabilizing diode (2221) and the amplifying circuit (2222); the cathode of the voltage-stabilizing diode (2221) is connected to the power supply of the LED module; the anode of the voltage-stabilizing diode (2221) is connected to the first fixed end of the potentiometer (2223); the second fixed end of the potentiometer (2223) is grounded; the first end of the amplifying circuit (2222) is connected to the moving end of the potentiometer (2223); and the second end of the amplifying circuit (2222) is connected to the cathode of the third light-emitting diode.

2. The detection circuit according to claim 1, characterized in that The first indicator element (12) is a first light emitting diode, the signal input terminal of the LED module is connected to the input end of the AND gate circuit (11), the anode of the first light emitting diode is connected to the first power supply, and the cathode of the first light emitting diode is connected to the output end of the AND gate circuit (11).

3. The detection circuit according to claim 2, characterized in that: The signal input terminal of the LED module includes a high-level input terminal and a low-level input terminal, the high-level input terminal is connected to the first input terminal of the AND gate circuit (11), and the low-level input terminal is connected to the second input terminal of the AND gate circuit (11), and the signal detection circuit (10) further includes a NOT gate circuit (13) arranged between the low-level input terminal and the second input terminal.

4. The detection circuit according to claim 1, characterized in that: The first power detection circuit (21) comprises a second power supply (212), the second indicator element (211) is a second light-emitting diode, the anode of the second light-emitting diode is connected to the positive electrode of the second power supply (212), and the cathode of the second light-emitting diode is connected to the power supply of the LED module.

5. The detection circuit according to claim 4, characterized in that: The first power supply detection circuit (21) further includes a charging detection circuit (213) provided at both ends of the second power supply (212), the charging detection circuit (213) including a comparator (2131), the positive electrode of the second power supply (212) being connected to the reverse input end of the comparator (2131), and the positive input end of the comparator (2131) being connected to the third power supply.

6. The detection circuit according to claim 5, characterized in that: The charging detection circuit (213) further comprises a constant current charging circuit (2132), the constant current charging circuit (2132) comprising a constant voltage circuit (2133), a first constant current circuit (2134), a first transistor (2135) and a second constant current circuit (2136), wherein the first transistor (2135) is a PNP-type transistor, a first end of the constant voltage circuit (2133) is connected to a first end of the first constant current circuit (2134), a second end of the constant voltage circuit (2133) is connected to a base of the first transistor (2135), a second end of the first constant current circuit (2134) is connected to an emitter of the first transistor (2135), a first end of the second constant current circuit (2136) is connected to a collector of the first transistor (2135), and a second end of the second constant current circuit (2136) is connected to the second power supply (212) for charging the second power supply (212).

7. The detection circuit according to claim 6, characterized in that: The charging detection circuit (213) further comprises a second triode (2137), wherein the second triode (2137) is an NPN-type triode, wherein the base of the second triode (2137) is connected to the output end of the comparator (2131), the emitter of the second triode (2137) is grounded, and the collector of the second triode (2137) is connected to the base of the first triode (2135).

8. The detection circuit according to claim 1, characterized in that: The amplifying circuit (2222) comprises a third triode (2224) and a fourth triode (2225); the third triode (2224) and the fourth triode (2225) are both NPN-type triodes; the base of the third triode (2224) is connected to the anode of the voltage-stabilizing diode (2221); the collector of the third triode (2224) is connected to the base of the fourth triode (2225); and the collector of the fourth triode (2225) is connected to the cathode of the third light-emitting diode.

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