Temperature detection circuit of LED display screen and LED display system

Abstract

The utility model discloses a temperature detection circuit of an LED display screen and an LED display system, the temperature detection circuit comprises a plurality of temperature detection modules, the plurality of temperature detection modules are in one-to-one correspondence with a plurality of LED lamp panels included in the LED display screen, and each temperature detection module comprises a temperature detection unit arranged on the LED lamp panel and used for detecting the temperature of the LED lamp panel, a power supply control signal is output according to the detected temperature information; and the power supply control unit is connected with the temperature detection unit, is also connected between the LED lamp panel and the power supply, and is used for controlling the connection and disconnection between the LED lamp panel and the power supply according to the power supply control signal output by the temperature detection unit. According to the technical scheme, temperature detection can be carried out on each LED lamp panel in the LED display screen, and the granularity of temperature detection of the LED display screen is refined; when the temperature of any LED lamp panel is abnormal, the position of the lamp panel can be quickly determined through the temperature detection unit corresponding to the corresponding LED lamp panel, so that the maintenance efficiency of the LED lamp panel is improved.

Description

Technical Field

[0001] The present application belongs to the technical field of display screens, and specifically relates to a temperature detection circuit for an LED display screen and an LED display system. Background Art

[0002] In the LED (Light-Emitting Diode) display industry, "large screens" are often talked about with great relish. Hundreds or even thousands of square meters of screen space create stunning visual effects that are truly eye-catching. In the digital age, LED displays have become a vital vehicle for urban landscapes and advertising, and have become ubiquitous in every corner of cities.

[0003] However, with widespread adoption, safety concerns about LED displays are becoming increasingly prominent, particularly regarding fire safety. LEDs generate a certain amount of heat during operation, which, combined with the high ambient temperature, can lead to malfunctions. If a malfunction occurs, the power supply cannot be disconnected promptly, resulting in continued high temperatures and potentially fires.

[0004] Therefore, preventing the LED display from burning is a major problem. It is necessary to design a device that can check the temperature at any time and cut off the power supply in time when an abnormality occurs to prevent the LED display from burning.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to ordinary technicians in this field. Summary of the Invention

[0006] The purpose of this application is to provide a temperature detection circuit and an LED display system for an LED display screen, so as to refine the granularity of temperature detection of the LED display screen and facilitate rapid location of abnormal temperature areas in the LED display screen.

[0007] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by practice of the present application.

[0008] According to one aspect of an embodiment of the present application, a temperature detection circuit for an LED display screen is provided. The temperature detection circuit includes a plurality of temperature detection modules. The plurality of temperature detection modules correspond one-to-one to a plurality of LED light boards included in the LED display screen. The temperature detection modules include:

[0009] a temperature detection unit, provided on the LED light board, for detecting the temperature of the LED light board and outputting a power control signal according to the detected temperature information;

[0010] A power control unit is connected to the temperature detection unit and is also connected between the LED light board and the power supply, and is used to control the conduction and disconnection between the LED light board and the power supply according to the power control signal output by the temperature detection unit.

[0011] In one embodiment of the present application, the temperature detection unit includes multiple groups of temperature measurement units and NAND gate chips, and the NAND gate chip includes multiple input pins and one output pin; one group of the temperature measurement units is connected to an input pin of the NAND gate chip, and the output pin of the NAND gate chip is connected to the power control unit.

[0012] In one embodiment of the present application, the temperature measuring unit includes a voltage divider resistor and a thermistor, the first end of the voltage divider resistor is connected to the working power supply, the second end of the voltage divider resistor is connected to the first end of the thermistor, and the second end of the thermistor is grounded; the second end of the voltage divider resistor is also connected to an input pin of the NAND gate chip.

[0013] In one embodiment of the present application, the temperature measuring units in each group use the same voltage divider resistor, and the temperature measuring units in each group use the same thermistor.

[0014] In one embodiment of the present application, the power control unit includes a fuse unit and a switch unit, the fuse unit is connected between the LED light board and the power supply, and the switch unit is connected to the fuse unit and the NAND gate chip respectively.

[0015] In one embodiment of the present application, the switching unit includes a switching tube and a current-controlling resistor, the first end of the switching tube is grounded, the second end of the switching tube is connected to the output pin of the NAND gate chip, the third end of the switching tube is connected to one end of the current-controlling resistor, and the other end of the current-controlling resistor is connected to the fuse unit.

[0016] In one embodiment of the present application, the switch tube is an N-type metal oxide semiconductor field effect transistor, the first end of the switch tube is the source of the N-type metal oxide semiconductor field effect transistor, the second end of the switch tube is the gate of the N-type metal oxide semiconductor field effect transistor, and the third end of the switch tube is the drain of the N-type metal oxide semiconductor field effect transistor.

[0017] In one embodiment of the present application, the temperature detection unit includes 8 groups of temperature measurement units and a NAND gate chip, and the NAND gate chip includes 8 input pins and 1 output pin.

[0018] In one embodiment of the present application, a power pin of the NAND gate chip is connected to a working power supply, the power pin is also connected to one end of a capacitor, and the other end of the capacitor is grounded.

[0019] According to one aspect of an embodiment of the present application, there is provided an LED display system, comprising:

[0020] LED display screen, including multiple LED light panels;

[0021] Power supply;

[0022] A temperature detection circuit is connected between the power supply and the multiple LED light boards. The temperature detection circuit is the temperature detection circuit of the LED display screen provided in any embodiment of the present application.

[0023] In the technical solution provided in the embodiment of the present application, the temperature detection circuit of the LED display screen includes multiple temperature detection modules, and the multiple temperature detection modules correspond one-to-one to the multiple LED light boards included in the LED display screen. The temperature detection modules include: a temperature detection unit, which is arranged on the LED light board, and is used to detect the temperature of the LED light board and output a power control signal according to the detected temperature information; a power control unit, which is connected to the temperature detection unit and is also connected between the LED light board and the power supply, and is used to control the conduction and disconnection between the LED light board and the power supply according to the power control signal output by the temperature detection unit. In this way, temperature detection can be performed separately for each LED light board in the LED display screen, thereby refining the granularity of the temperature detection of the LED display screen; and when the temperature of any LED light board is abnormal, the position of the light board can be quickly determined by the temperature detection unit corresponding to the LED light board, thereby improving the maintenance efficiency of the LED light board.

[0024] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0026] Figure 1 The figure schematically shows a device for detecting the temperature of an LED display screen in the prior art.

[0027] Figure 2The following schematically shows a temperature detection circuit diagram of an LED display screen provided by an embodiment of the present application.

[0028] Figure 3 The following schematically shows a schematic diagram of an LED display system provided by an embodiment of the present application.

[0029] Figure 4 The figure schematically shows a circuit diagram of a temperature detection unit provided in one embodiment of the present application.

[0030] Figure 5 The figure schematically shows a circuit diagram of a power control unit provided in one embodiment of the present application.

[0031] Figure 6 The figure schematically shows the voltage change of the input pin of the NAND gate chip provided by one embodiment of the present application. DETAILED DESCRIPTION

[0032] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art.

[0033] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner.In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps etc. can be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0034] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically separate entities. That is, these functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0035] Figure 1 The figure schematically shows a device for detecting the temperature of an LED display screen in the prior art.

[0036] like Figure 1As shown, the LED display cabinet includes a power supply, a HUB (hub) board and multiple light boards, wherein the HUB board is provided with a relay and a single-chip microcomputer. The power supply is connected to each light board through a relay, and the single-chip microcomputer is connected to the relay and each light board. The HUB board is also connected to other devices in the LED display system to obtain LED display data. The power supply is the power supply of the LED light board. The single-chip microcomputer sends a light board display control signal to each light board to control the display of each light board, such as controlling the brightness of the light board and turning the light board on / off. A thermistor is placed on the light board to detect the temperature of the light board. At the same time, each light board outputs a temperature detection signal to the single-chip microcomputer on the HUB. After the single-chip microcomputer processes these signals, the single-chip microcomputer outputs a control signal to the relay. When the single-chip microcomputer detects that the temperature of one or more light boards is abnormal, it sends a control signal to disconnect the relay. At this time, the power supply of all light boards is cut off, thereby preventing the light boards from burning due to high temperature.

[0037] according to Figure 1 As can be seen from the technical solution shown, the total power supply to each light panel of the entire LED display is controlled by only one relay. The relay needs to withstand a very large current. In addition, the temperature inside the cabinet of the outdoor LED display can reach over 50 degrees Celsius when the display is in operation. The life of the relay is greatly affected by temperature. Long-term operation at high temperatures will reduce the service life. At the same time, because the power supply to the light panels of the entire cabinet is controlled together, if an abnormality occurs (such as the display screen temperature is too high), all the light panels in the entire cabinet will be powered off and the screen will go black. It is impossible to quickly locate the faulty light panel, which reduces maintenance efficiency. Finally, the detection circuit has no memory function. The relay will reset after powering off and then on, thereby repeatedly triggering the protection mechanism.

[0038] Based on the above problems, the present application proposes a temperature detection circuit for an LED display screen. The temperature detection circuit for an LED display screen provided by the present application is described in detail below in conjunction with specific implementation methods.

[0039] Figure 2 The following schematically shows a schematic diagram of a temperature detection circuit of an LED display screen provided by an embodiment of the present application. Figure 2 As shown, the temperature detection circuit includes multiple temperature detection modules 231, wherein the temperature detection modules 231 correspond one to one with the LED light boards included in the LED display screen, that is, one temperature detection module 231 is used to perform temperature detection on one LED light board.

[0040] Furthermore, each temperature detection module 231 includes a temperature detection unit 2311 and a power control unit 2312, wherein the temperature detection unit 2311 is arranged on the LED light board, and is used to detect the temperature of the LED light board, and output a power control signal based on the detected temperature information; the power control unit 2312 is connected to the temperature detection unit 2311, and is also connected between the LED light board and the power supply, and is used to control the conduction and disconnection between the LED light board and the power supply according to the power control signal output by the temperature detection unit 2311.

[0041] Figure 3 A schematic diagram of an LED display system provided by an embodiment of the present application is schematically shown. The LED display system is suitable for the temperature detection circuit of the LED display screen proposed in the technical solution of the present application.

[0042] like Figure 3 As shown, the LED display system includes a power supply 210, an LED display screen 220, and a temperature detection circuit 230. The LED display screen 220 includes multiple LED light panels 221, each of which includes multiple LED lamp beads. The temperature detection circuit 230 includes multiple temperature detection modules 231. Each LED light panel 221 corresponds to a temperature detection module 231, so each LED light panel 221 has an independent temperature detection module 231.

[0043] The temperature detection module 231 includes a temperature detection unit 2311 and a power control unit 2312. The temperature detection unit 2311 is provided on the LED light board 221 and is used to detect the temperature of the LED light board 221 and output a power control signal based on the detected temperature information. The power control unit 2312 is connected to the temperature detection unit 2311 and is also connected between the LED light board 221 and the power supply 210. The power control unit 2312 is used to control the connection and disconnection between the LED light board 221 and the power supply 210 based on the power control signal output by the temperature detection unit 2311.

[0044] In one embodiment of the present application, the LED display system includes a HUB board, and the power control unit 2312 can be set on the HUB board.

[0045] When the LED display system is operating, the power supply 210 of the LED display screen is turned on, and current is supplied to the LED light board 221 through the power control unit 2312. After the LED light board 221 is powered on, it lights up and operates normally. The temperature detection unit 2311 monitors the temperature information of the LED light board 221 in real time. When no abnormality occurs, that is, the temperature of the LED light board 221 is within the normal range, the power control signal sent by the temperature detection unit 2311 to the power control unit 2312 does not disconnect the LED light board 221 from the power supply 210, that is, it does not disconnect the power supply to the LED light board 221. When an abnormality is detected in the LED light board 221, that is, the temperature of the LED light board 221 exceeds the normal range, the temperature detection unit 2311 sends a power control signal to the power control unit 2312 to disconnect the power supply to the light board, that is, disconnect the LED light board 221 from the power supply 210, thereby protecting the LED light board 221 and preventing the LED light board 221 from being in a high temperature state for a long time and causing combustion problems. At the same time, the power control unit 2312 has a built-in memory function. Once the protection is triggered (i.e., the power supply to the light board is cut off), it will take effect permanently and will not be repeatedly triggered because the LED display screen is powered off and then powered on.

[0046] In the technical solution provided in the embodiment of the present application, the temperature detection circuit of the LED display screen includes multiple temperature detection modules, and the multiple temperature detection modules correspond one-to-one to the multiple LED light boards included in the LED display screen. The temperature detection modules include: a temperature detection unit, which is arranged on the LED light board, and is used to detect the temperature of the LED light board and output a power control signal according to the detected temperature information; a power control unit, which is connected to the temperature detection unit and is also connected between the LED light board and the power supply, and is used to control the conduction and disconnection between the LED light board and the power supply according to the power control signal output by the temperature detection unit. In this way, temperature detection can be performed separately for each LED light board in the LED display screen, thereby refining the granularity of the temperature detection of the LED display screen; and when the temperature of any LED light board is abnormal, the position of the light board can be quickly determined by the temperature detection unit corresponding to the LED light board, thereby improving the maintenance efficiency of the LED light board.

[0047] Figure 4 A circuit diagram of a temperature detection unit provided in one embodiment of the present application is schematically shown. The temperature detection unit is the temperature detection unit in the temperature detection module provided in any embodiment of the present application.

[0048] like Figure 4 As shown, the temperature detection unit includes multiple groups of temperature measurement units 410 and a NAND gate chip U1. The NAND gate chip U1 includes multiple input pins and one output pin; one group of temperature measurement units 410 is connected to an input pin of the NAND gate chip U1, and the output pin of the NAND gate chip U1 is connected to the power control unit.

[0049] like Figure 4 As shown, NAND gate chip U1 uses the CD74HC30 model. It has 14 pins, of which pins 1-6 and 11-12 are input pins, totaling 8; pin 8 is an output pin. Input pins 1-6 and 11-12 can also be labeled V_IN1-8, and are recorded as V_IN1-8 pins; output pin 8 can also be labeled Control, and is recorded as the Control pin.

[0050] Further, such as Figure 4 As shown, pin 14 of NAND gate chip U1 is a power pin, also known as the VDD pin, which is connected to the operating power supply. Pin 7 of NAND gate chip U1 is a ground pin, also known as the GND pin, which is connected to ground. The VDD pin of NAND gate chip U1 is also connected to one end of capacitor C1, and the other end of capacitor C1 is grounded to GND.

[0051] Furthermore, the temperature measuring unit 410 includes a voltage divider resistor Ri and a thermistor RTi, wherein i represents the i-th group of temperature measuring units 410. Figure 4 As shown, the first group of temperature measurement units 410 includes a voltage divider resistor R1 and a thermistor RT1, the second group of temperature measurement units 410 includes a voltage divider resistor R2 and a thermistor RT2, and so on. Figure 4 A total of 8 groups of temperature measurement units 410 are included.

[0052] In each group of temperature measurement units 410, the voltage divider resistor Ri and the thermistor RTi are connected in series, that is, the second end of the voltage divider resistor Ri is connected to the first end of the thermistor RTi, and the common connection end of the two is connected to the input pin of the NAND gate chip U1. Among them, the common connection end of the i-th group of temperature measurement units 410 is connected to the input pin V_INi of the NAND gate chip U1. For example, Figure 4 As shown, the common connection terminal of the first group of temperature measurement units 410 is connected to the input pin V_IN1 of the NAND gate chip U1, the common connection terminal of the second group of temperature measurement units 410 is connected to the input pin V_IN2 of the NAND gate chip U1, and so on. The first end of the voltage divider resistor Ri is connected to the operating power supply VDD, and the second end of the thermistor RTi is connected to the ground GND.

[0053] In the multiple groups of temperature measuring units 410, each group of temperature measuring units 410 uses the same voltage divider resistor and the same thermistor. Figure 4As shown, the voltage divider resistors (R1-8) used by each group of temperature measuring units 410 are all 2.23k (unit: ohm, Ω), and the thermistors (RT1-8) used by each group of temperature measuring units 410 are all model EWTF05-103F3I. The resistance of this type of thermistor decreases as the temperature rises. When the temperature is 25 degrees, the resistance is 10K, and when the temperature is 100 degrees, the resistance is 1K.

[0054] In this embodiment, the CD74HC30 NAND gate chip U1 is an eight-input NAND gate. When all eight inputs are high, the output is low; as long as one input is low, the output is high. Its truth table is shown in Table 1 below.

[0055] Table 1

[0056]

[0057] Among them, H represents a high level, L represents a low level, and X represents that it can be either a high level or a low level.

[0058] When powered by 4.2V, the low-level input voltage of the CD74HC30 NAND gate chip U1 is 1.3V. Using a 2.23K resistor in series with the thermistor to divide the voltage, the voltage at the input pin of the CD74HC30 NAND gate chip U1 is 1.28V at a temperature of 100°C. When the temperature is below 100°C, the voltage at the input pin of the CD74HC30 NAND gate chip U1 is greater than 1.3V, indicating a high-level input and a low-level output. When the temperature exceeds 100°C, the voltage at the input pin of the CD74HC30 NAND gate chip U1 is less than 1.3V, indicating a low-level input and a high-level output. Because the outdoor light panel can reach a maximum temperature of 80°C during normal operation due to environmental influences, the temperature threshold for LED light panel abnormalities is set to 100°C to avoid misjudgments. If the temperature exceeds 100°C, the LED light panel is considered abnormal and the temperature has risen, and the power supply to the LED light panel needs to be disconnected.

[0059] Figure 5 A circuit diagram of a power control unit provided in one embodiment of the present application is schematically shown. The power control unit is the power control unit in the temperature detection module provided in any embodiment of the present application.

[0060] like Figure 5 As shown, the power control unit includes a fuse unit F1 and a switch unit 510, wherein the fuse unit F1 is connected between the LED light board and the power supply VCC, and the switch unit 510 is connected to the fuse unit F1 and the NAND gate chip respectively. The NAND gate chip can be Figure 4 The NAND gate chip U1 is shown.

[0061] In one embodiment of the present application, the fuse unit F1 is a fuse, and a fuse model JFC1206-2150FS can be used, with a rated current of 15A. The maximum current of the LED light board during normal use is 11A.

[0062] Further, such as Figure 5 As shown, the switch unit 510 includes a switch tube Q1 and a current-control resistor R9. The first end of the switch tube Q1 is grounded GND, the second end of the switch tube Q1 is connected to the output pin Control of the NAND gate chip U1, the third end of the switch tube Q2 is connected to one end of the current-control resistor R9, and the other end of the current-control resistor R9 is connected to the fuse unit F1. This connection point also belongs to the voltage input terminal VDD of the LED lamp board.

[0063] Further, such as Figure 5 As shown, the switch transistor is an N-type metal-oxide-semiconductor (NMOS) field-effect transistor, or NMOS for short. The first terminal of NMOS transistor Q1 serves as the source, the second terminal of NMOS transistor Q1 serves as the gate, and the third terminal of NMOS transistor Q1 serves as the drain. Therefore, the gate of NMOS transistor Q1 is connected to the output pin Control of NAND chip U1, the source of NMOS transistor Q1 is grounded GND, and the drain of NMOS transistor Q1 is connected to current-control resistor R9.

[0064] In one embodiment of the present application, the NMOS transistor Q1 uses the FSD90N03A model. When the gate voltage is greater than 2.2V, the NMOS transistor Q1 is turned on. The high-level voltage output by the CD74HC30 NAND gate chip U1 is 4.2V, and the low-level voltage is less than 0.1V. When the temperature of the LED light board is within 100 degrees, the CD74HC30 NAND gate chip U1 outputs a low level, and the NMOS transistor Q1 is not turned on; when the temperature of the LED light board exceeds 100 degrees, the CD74HC30 NAND gate chip U1 outputs a high level, turning on the NMOS transistor Q1, and the current flowing through the fuse F1 increases instantly, causing the fuse to blow. The NMOS transistor Q1 is connected in series with a 100 milliohm current-control resistor R9. The function of this current-control resistor R9 is to control the current flowing through the NMOS transistor Q1 when it is turned on, thereby controlling the time it takes for the fuse F1 to blow.

[0065] The experimental data of the technical solution of this application are given below.

[0066] Turn on the power of the LED light board and adjust the brightness of the light board to 100%. Use a heat gun to slowly heat the LED light board to simulate the abnormal temperature of the LED light board. Use a multimeter to measure the voltage of the input pin of the CD74HC30 NAND gate chip U1. You can see that the voltage of the input pin of the CD74HC30 NAND gate chip U1 keeps decreasing. Figure 6 shown.

[0067] When the temperature reaches 100°C, the voltage at the input pin of the CD74HC30 NAND gate chip U1 drops to 1.288V, which is less than 1.3V. At this time, the voltage output by the output pin of the CD74HC30 NAND gate chip U1 is 4.18V, which is a high-level signal and is given to the NMOS tube Q1. The NMOS tube Q1 is turned on and the conduction current is 41.47A.

[0068] After 0.9 seconds, fuse F1 on the JFC1206-2150FS blew. I replaced the blown fuse, set the light panel brightness to 50%, and heated the panel to over 100°C. F1 took 1.2 seconds to blow. Finally, I lowered the panel brightness to 0% and tested again. F1 took 1.6 seconds to blow.

[0069] After testing, it was found that when the temperature of the LED light board exceeded the set value of 100°C, the CD74HC30 NAND gate chip U1 output a high-level signal to the gate of the NMOS tube Q1, causing the NMOS tube Q1 to turn on, thereby blowing the fuse F1 and cutting off the power supply to the LED light board, preventing the LED light board from burning due to high temperature.

[0070] Therefore, the technical solution of this application has the following advantages:

[0071] 1. Place multiple thermistors on the light board to detect temperature, covering the entire light board. Cooperating with NAND gate, it can detect temperature abnormality in real time and send out control signals.

[0072] 2. A combination of fuses and MOS tubes is used to control the power supply of the light board. When a temperature abnormality occurs, the fuse blows and the power supply of the light board is disconnected to prevent burning. Moreover, the fuse is permanently effective after it blows. The fuse is stable and reliable, which can reduce costs.

[0073] 3. The power supply of each light panel can be controlled individually. When an abnormality occurs, the power supply is disconnected individually, which will not cause the power supply of the light panels of the entire box to be disconnected and the entire box to be black. It is convenient to locate the faulty light panel and reduce the impact on the display effect of the entire LED large screen before maintenance.

[0074] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of this application and include common knowledge or customary techniques in the art that are not disclosed herein.

[0075] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A temperature detection circuit for an LED display, characterized in that: The temperature detection circuit includes a plurality of temperature detection modules, each of which corresponds to a plurality of LED light panels included in the LED display screen. The temperature detection module includes: a temperature detection unit, provided on the LED light board, for detecting the temperature of the LED light board and outputting a power control signal according to the detected temperature information; A power control unit is connected to the temperature detection unit and is also connected between the LED light board and the power supply, and is used to control the conduction and disconnection between the LED light board and the power supply according to the power control signal output by the temperature detection unit.

2. The temperature detection circuit of the LED display screen according to claim 1, characterized in that: The temperature detection unit includes multiple groups of temperature measurement units and NAND gate chips, and the NAND gate chip includes multiple input pins and one output pin; one group of the temperature measurement units is connected to an input pin of the NAND gate chip, and the output pin of the NAND gate chip is connected to the power control unit.

3. The temperature detection circuit of the LED display screen according to claim 2, characterized in that: The temperature measurement unit includes a voltage divider resistor and a thermistor, the first end of the voltage divider resistor is connected to the working power supply, the second end of the voltage divider resistor is connected to the first end of the thermistor, and the second end of the thermistor is grounded; the second end of the voltage divider resistor is also connected to an input pin of the NAND gate chip.

4. The temperature detection circuit of the LED display screen according to claim 3, characterized in that: The temperature measuring units in each group use the same voltage divider resistor, and the temperature measuring units in each group use the same thermistor.

5. The temperature detection circuit of the LED display screen according to claim 2, characterized in that: The power control unit includes a fuse unit and a switch unit. The fuse unit is connected between the LED lamp board and the power supply. The switch unit is connected to the fuse unit and the NAND gate chip respectively.

6. The temperature detection circuit of the LED display screen according to claim 5, characterized in that: The switching unit includes a switching tube and a current-controlling resistor, the first end of the switching tube is grounded, the second end of the switching tube is connected to the output pin of the NAND gate chip, the third end of the switching tube is connected to one end of the current-controlling resistor, and the other end of the current-controlling resistor is connected to the fuse unit.

7. The temperature detection circuit of the LED display screen according to claim 6, characterized in that: The switch tube is an N-type metal oxide semiconductor field effect transistor, the first end of the switch tube is the source of the N-type metal oxide semiconductor field effect transistor, the second end of the switch tube is the gate of the N-type metal oxide semiconductor field effect transistor, and the third end of the switch tube is the drain of the N-type metal oxide semiconductor field effect transistor.

8. The temperature detection circuit of the LED display screen according to claim 2, characterized in that: The temperature detection unit includes 8 groups of temperature measurement units and a NAND gate chip. The NAND gate chip includes 8 input pins and 1 output pin.

9. The temperature detection circuit of the LED display screen according to claim 2, characterized in that: The power pin of the NAND gate chip is connected to a working power supply, and the power pin is also connected to one end of a capacitor, and the other end of the capacitor is grounded.

10. An LED display system, characterized in that: include: LED display screen, including multiple LED light panels; Power supply; A temperature detection circuit, wherein the temperature detection circuit is connected between the power supply and the plurality of LED light boards, and the temperature detection circuit is the temperature detection circuit of the LED display screen according to any one of claims 1 to 9.

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