Power supply circuit and display screen

Abstract

The utility model discloses a power supply circuit and a display screen, the power supply circuit comprises a voltage acquisition circuit, the voltage acquisition circuit is electrically connected with the output end of a second power supply module, and the voltage acquisition circuit is used for acquiring the output voltage of the second power supply module and outputting a corresponding voltage acquisition signal; the input end of the third power supply module is used for being connected with a power supply; the main control circuit is electrically connected with the controlled end of the first power supply module, the output end of the voltage acquisition circuit and the output end of the third power supply module; the third power supply module is used for converting the power supply and outputting the power supply to the main control circuit so as to supply power to the main control circuit; the main control circuit is used for controlling the first power supply module and the second power supply module to be restarted when the output of the second power supply module is detected to be abnormal according to the voltage acquisition signal; the utility model aims to solve the technical problem that the display screen cannot automatically recover normal work when a transient short-circuit fault occurs in the power supply system of the existing display screen.

Description

Technical Field

[0001] This utility model relates to the field of display screen technology, and in particular to a power supply circuit and a display screen. Background Technology

[0002] Currently, an LCD screen comprises an LCD display, a main control system, and a communication module. The power supply for the LCD display, main control system, and communication module is typically provided by the same power supply module. For example, see reference... Figure 1 For example, in a common structure, a power supply module includes a first power supply module and a second power supply module. The power supply first undergoes preliminary voltage conversion through the first power supply module to provide a stable operating voltage for the main control system and communication module; simultaneously, the power output is further connected to the second power supply module to adapt to the specific voltage level required by the LCD screen display, thereby completing the power supply to the LCD screen display.

[0003] However, this power supply structure has certain reliability flaws. Specifically, the second power module usually has a short-circuit protection function. When a brief short-circuit fault occurs at its power output terminal, the second power module will automatically enter a locked state to prevent damage. However, the second power module will stop outputting when it enters the locked state, and it cannot automatically restore power supply when the short-circuit fault disappears. This causes the LCD screen to lose power and fail to work properly after a brief short-circuit fault, seriously affecting the stability of the LCD screen and the user experience. Utility Model Content

[0004] The main purpose of this utility model is to propose a power supply circuit and display screen, which aims to solve the technical problem that the power supply system of the existing display screen cannot automatically resume normal operation when a brief short circuit fault occurs.

[0005] To achieve the above objectives, this utility model proposes a power supply circuit applied to a display screen. The display screen includes a display screen body, and the power supply circuit includes a first power module and a second power module. The input terminal of the first power module is used to connect to a power supply, the output terminal of the first power module is electrically connected to the input terminal of the second power module, and the output terminal of the second power module is electrically connected to the display screen body. The power supply circuit further includes:

[0006] A voltage acquisition circuit is electrically connected to the output terminal of the second power module. The voltage acquisition circuit is used to acquire the output voltage of the second power module and output a corresponding voltage acquisition signal.

[0007] The third power module, wherein the input terminal of the third power module is used to connect to the power supply;

[0008] The main control circuit is electrically connected to the controlled terminal of the first power module, the output terminal of the voltage acquisition circuit, and the output terminal of the third power module, respectively. The third power module is used to convert the power supply and output it to the main control circuit to power the main control circuit.

[0009] The main control circuit is used to control the first power module to restart when an abnormality is detected in the output of the second power module based on the voltage acquisition signal. The second power module automatically restarts when the first power module restarts and restores its output voltage.

[0010] In one embodiment, the voltage acquisition circuit includes:

[0011] A voltage divider circuit is provided, wherein the input terminal of the voltage divider circuit is connected to the output terminal of the second power module, and the output terminal of the voltage divider circuit is electrically connected to the main control circuit.

[0012] In one embodiment, the voltage divider circuit includes:

[0013] A first resistor and a second resistor, wherein the first end of the first resistor is connected to the output terminal of the second power module, the second end of the first resistor is connected to the first end of the second resistor, the second end of the second resistor is grounded, and the first end of the second resistor is also electrically connected to the main control circuit.

[0014] In one embodiment, the power supply circuit further includes:

[0015] The circuit includes a filter circuit and an amplifier circuit. The input terminal of the amplifier circuit is connected to the output terminal of the voltage acquisition circuit, the output terminal of the amplifier circuit is connected to the input terminal of the filter circuit, and the output terminal of the filter circuit is electrically connected to the main control circuit.

[0016] In one embodiment, the filtering circuit includes:

[0017] A third resistor and a first capacitor are connected, with the first end of the third resistor connected to the input terminal of the amplifier circuit, the second end of the third resistor electrically connected to the first end of the first capacitor and the main control circuit, and the second end of the first capacitor grounded.

[0018] In one embodiment, the amplification circuit includes:

[0019] An operational amplifier, a fourth resistor, and a fifth resistor are provided. The first end of the fourth resistor is connected to the output terminal of the voltage acquisition circuit, the second end of the fourth resistor is connected to the first end of the fifth resistor, the first end of the fifth resistor is also connected to the inverting input of the operational amplifier, the output terminal of the operational amplifier is connected to the input terminal of the filter circuit and the second end of the fifth resistor, and the non-inverting input of the operational amplifier is grounded.

[0020] This utility model also proposes a display screen, including a display screen body and a power supply circuit as described in any of the above claims; the display screen body is electrically connected to the power supply circuit.

[0021] In one embodiment, the display screen further includes:

[0022] The communication module is electrically connected to the output terminals of the main control circuit and the third power supply module, respectively, and is used to establish a communication connection with an external terminal.

[0023] In one embodiment, the display screen further includes:

[0024] The backlight switch has a first power output terminal and a second power output terminal. The first power output terminal is electrically connected to the display screen body. The input terminal of the backlight switch is connected to the second power output terminal. The output terminal of the backlight switch is electrically connected to the display screen body. The controlled terminal of the backlight switch is electrically connected to the main control circuit.

[0025] This invention employs a voltage acquisition circuit to monitor the operating status of the second power module in real time. Upon detecting an abnormal output, the main control circuit restarts both the first and second power modules. Simultaneously, a third power module, independent of the first and second power modules, provides dedicated power to the main control circuit, ensuring its normal operation even after the first power module restarts. This design enables automatic power restoration after short-term recoverable faults such as short circuits, improving the stability and fault tolerance of the power supply system and significantly enhancing the reliability and continuity of the display screen's operation. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the power supply circuit for an existing display screen;

[0028] Figure 2 This is a schematic diagram of a module according to an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the circuit structure of an embodiment of the present invention;

[0030] Figure 4 This is a schematic diagram of a module according to another embodiment of the present invention;

[0031] Figure 5 This is a schematic diagram of the circuit structure of another embodiment of the present invention;

[0032] Figure 6 This is a schematic diagram of a module according to another embodiment of the present invention.

[0033] Explanation of icon numbers:

[0034] 10. First power supply module; 20. Second power supply module; 30. Voltage acquisition circuit; 40. Third power supply module; 50. Main control circuit; 60. Filtering circuit; 70. Amplification circuit; 80. Communication module; 90. Backlight switch.

[0035] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0036] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0037] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0038] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0039] Currently, an LCD screen comprises an LCD display, a main control system, and a communication module. The power supply for the LCD display, main control system, and communication module is typically provided by the same power supply module. For example, see reference... Figure 1 For example, in a common structure, a power supply module includes a first power supply module and a second power supply module. The power supply first undergoes preliminary voltage conversion through the first power supply module to provide a stable operating voltage for the main control system and communication module; simultaneously, the power output is further connected to the second power supply module to adapt to the specific voltage level required by the LCD screen display, thereby completing the power supply to the LCD screen display.

[0040] However, this power supply structure has certain reliability flaws. Specifically, the second power module usually has a short-circuit protection function. When a brief short-circuit fault occurs at its power output terminal, the second power module will automatically enter a locked state to prevent damage. However, the second power module will stop outputting when it enters the locked state, and it cannot automatically restore power supply when the short-circuit fault disappears. This causes the LCD screen to lose power and fail to work properly after a brief short-circuit fault, seriously affecting the stability of the LCD screen and the user experience.

[0041] Therefore, this utility model proposes a power supply circuit and a display screen, aiming to solve the technical problem that the power supply system of the existing display screen automatically enters a locked state when a brief short circuit fault occurs, causing the display screen to be unable to automatically resume normal operation.

[0042] In one embodiment of this utility model, reference is made to Figure 2The power supply circuit includes a first power module 10 and a second power module 20. The input terminal of the first power module 10 is used to connect to a power supply, the output terminal of the first power module 10 is electrically connected to the input terminal of the second power module 20, and the output terminal of the second power module 20 is electrically connected to the display screen body. The power supply circuit also includes:

[0043] A voltage acquisition circuit 30 is electrically connected to the output terminal of the second power module 20. The voltage acquisition circuit 30 is used to acquire the output voltage of the second power module 20 and output a corresponding voltage acquisition signal.

[0044] The third power module 40, the input terminal of which is used to connect to the power supply;

[0045] The main control circuit 50 is electrically connected to the controlled terminal of the first power module 10, the output terminal of the voltage acquisition circuit 30, and the output terminal of the third power module 40. The third power module 40 is used to convert the power supply and output it to the main control circuit 50 to supply power to the main control circuit 50.

[0046] The main control circuit 50 is used to control the first power module 10 when an abnormal output of the second power module 20 is detected based on the voltage acquisition signal, and the second power module 20 automatically restarts when the first power module 10 restarts and restores its output voltage.

[0047] In this embodiment, the voltage acquisition circuit 30 can be implemented using a voltage divider circuit. The voltage divider circuit uses two or more resistors to proportionally reduce the output voltage of a second power supply module 20 to a range suitable for the ADC input processing of the main control circuit 50. For example, refer to... Figure 3 The voltage divider circuit includes:

[0048] A first resistor R1 and a second resistor R2 are connected. The first end of the first resistor R1 is connected to the output terminal of the second power module 20, and the second end of the first resistor R1 is connected to the first end of the second resistor R2. The second end of the second resistor R2 is grounded, and the first end of the second resistor R2 is also electrically connected to the main control circuit 50.

[0049] The first resistor R1 and the second resistor R2 form a series circuit to divide the output voltage of the second power module 20. The main control circuit 50 performs analog-to-digital conversion on the divided voltage value through its internal ADC to obtain the corresponding digital value, and calculates the output voltage of the second power module 20 according to the resistance ratio of the first resistor R1 and the second resistor R2.

[0050] In addition, the voltage acquisition circuit 30 can also be implemented using a voltage sensor, such as a resistive voltage sensor, a Hall effect voltage sensor, or a voltage transformer, etc., without limitation.

[0051] In this embodiment, when the second power module 20 detects a short circuit in the power supply circuit and automatically locks its output, the voltage output by the second power module 20 will gradually drop to zero. The main control circuit 50 is used to determine that the output of the second power module 20 is abnormal when it detects that the voltage output of the second power module 20 starts to drop to a preset voltage threshold (greater than zero). Thus, when the second power module 20 locks its output, it controls the first power module 10 to restart immediately in order to try to restore normal power supply to the display screen in the shortest possible time.

[0052] In this embodiment, the third power supply module 40 can be implemented using a DC / DC conversion module to convert the power supply voltage of the power supply into the operating voltage of the main control circuit 50 so that the main control circuit 50 can operate normally.

[0053] In this embodiment, the main control circuit 50 can be implemented using a main controller, such as an MCU (Microcontroller Unit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), or a SOC (System On Chip).

[0054] It should be noted that when the second power module 20 restarts, its locked output state can be reset so that the second power module 20 can restart and resume normal operation when the short circuit in the power supply circuit disappears, thereby restoring the display screen to normal operation.

[0055] It should be noted that when the first power module 10 is turned off, the second power module 20 loses its input voltage and naturally stops working; while when the first power module 10 restarts and restores its output voltage, the second power module 20 receives input power again and will automatically power on and restart.

[0056] This invention employs a voltage acquisition circuit 30 to monitor the operating status of the second power module 20 in real time. When an abnormal output is detected, the main control circuit 50 controls the first power module 10 and the second power module 20 to restart. Simultaneously, a third power module 40, independent of the first and second power modules 10, provides a separate power supply to the main control circuit 50, ensuring its normal operation even after the first power module 10 restarts. This configuration allows for automatic power restoration after short-term recoverable faults such as short circuits, improving the stability and fault tolerance of the power supply system and significantly enhancing the reliability and continuity of the display screen's operation.

[0057] It should be noted that the accuracy of the voltage acquisition circuit 30 directly affects the response speed and control efficiency of the main control circuit 50 to abnormal states of the second power module 20. Specifically, when the output voltage of the second power module 20 drops due to a short circuit, sudden load change, or other reasons, if the acquisition accuracy of the voltage acquisition circuit 30 is low, the voltage acquisition signal output to the main control circuit 50 will have a large error or delay. This will prevent the main control circuit 50 from accurately identifying the voltage abnormality in a timely manner, resulting in a delay in the restart of the first power module 10. With the restart of the first power module 10 delayed, the time for the display to return to normal operation increases accordingly, leading to a decline in the user experience.

[0058] In one embodiment of this utility model, reference is made to... Figure 4 The voltage acquisition circuit 30 further includes:

[0059] The circuit includes a filter circuit 60 and an amplifier circuit 70. The input terminal of the amplifier circuit 70 is connected to the output terminal of the voltage acquisition circuit 30, the output terminal of the amplifier circuit 70 is connected to the input terminal of the filter circuit 60, and the output terminal of the filter circuit 60 is electrically connected to the main control circuit 50.

[0060] In this embodiment, the amplifier circuit 70 is used to amplify the weak voltage signal output by the voltage acquisition circuit 30 to a voltage range suitable for the ADC module of the main control circuit 50 to be recognized, thereby improving the sampling resolution; the filter circuit 60 is used to filter out the high-frequency noise and interference components contained in the amplified voltage acquisition signal, ensuring that the voltage acquisition signal sent to the main control circuit 50 is stable and smooth.

[0061] After the above processing, the main control circuit 50 can identify the changing trend of the output voltage of the second power module 20 more quickly and accurately, and can respond before the voltage starts to drop but before the output is completely locked, thereby controlling the first power module 10 to restart in time.

[0062] In this embodiment, the filter circuit 60 can be implemented using an RC filter circuit, for example, refer to Figure 5 The filter circuit 60 includes:

[0063] The third resistor R3 and the first capacitor C1 are connected. The first end of the third resistor R3 is connected to the output terminal of the amplifier circuit 70, and the second end of the third resistor R3 is electrically connected to the first end of the first capacitor C1 and the main control circuit 50. The second end of the first capacitor C1 is grounded.

[0064] The third resistor R3 and the first resistor R1 form an RC filter circuit, which is used to filter out unnecessary high-frequency noise and interference components in the voltage acquisition signal, thereby improving the stability of the voltage acquisition signal and the accuracy of the main control circuit 50 in judging the output status of the second power module 20.

[0065] In this embodiment, the amplifier circuit 70 can be implemented using an operational amplifier, for example, refer to Figure 6 The discharge circuit includes:

[0066] The system comprises an operational amplifier U1, a fourth resistor R4, and a fifth resistor R5. The first end of the fourth resistor R4 is connected to the output terminal of the voltage acquisition circuit 30, the second end of the fourth resistor R4 is connected to the first end of the fifth resistor R5, the first end of the fifth resistor R5 is also connected to the inverting input of the operational amplifier U1, the output terminal of the operational amplifier U1 is connected to the input terminal of the filter circuit 60 and the second end of the fifth resistor R5, and the non-inverting input of the operational amplifier U1 is grounded.

[0067] Operational amplifier U1, fourth resistor R4, and fifth resistor R5 form an inverting amplifier circuit structure, which amplifies the voltage acquisition signal according to a preset ratio to the voltage range required by the input range of the main control circuit 50ADC, thereby improving the voltage acquisition accuracy and resolution.

[0068] This utility model also proposes a display screen, including a display screen body and a power supply circuit as described above; the display screen body is electrically connected to the power supply circuit.

[0069] It is worth noting that since the display screen of this utility model is based on the power supply circuit described above, the embodiments of the display screen of this utility model include all the technical solutions of all the embodiments of the power supply circuit described above, and the technical effects achieved are exactly the same, so they will not be repeated here.

[0070] In one embodiment of this utility model, reference is made to Figure 6 The display screen also includes:

[0071] The communication module 80 is electrically connected to the output terminals of the main control circuit 50 and the third power supply module 40, respectively, and is used to establish a communication connection with an external terminal.

[0072] This configuration, through the communication module 80, enables the display screen to communicate with external terminals (such as hosts, upper-level computers, mobile devices, etc.), thereby enhancing the display screen's intelligence and scalability. Furthermore, since the communication module 80 is powered independently by the third power module 40, it can continue operating even if the first power module 10 or the second power module 20 fails, ensuring that the display screen's system status information is not lost.

[0073] In one embodiment of this utility model, reference is made to Figure 6 The display screen also includes:

[0074] The backlight switch 90 and the second power module 20 have a first power output terminal and a second power output terminal. The first power output terminal is electrically connected to the display screen body. The input terminal of the backlight switch 90 is connected to the second power output terminal, the output terminal of the backlight switch 90 is electrically connected to the display screen body, and the controlled terminal of the backlight switch 90 is electrically connected to the main control circuit 50. The first power output terminal provides the main power supply voltage to the display screen body, and the second power output terminal drives the backlight system of the display screen body.

[0075] This configuration, through the backlight switch 90 controlled by the main control circuit 50, enables intelligent control of the backlight strip. It not only allows for adjusting the backlight brightness as needed to save energy, but also enables timely disconnection of backlight power supply in case of power module malfunction, thereby improving the safety and reliability of the display screen.

[0076] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A power supply circuit applied to a display screen, the display screen including a display screen body, the power supply circuit including a first power module and a second power module, the input terminal of the first power module being used to connect to a power supply, the output terminal of the first power module being electrically connected to the input terminal of the second power module, and the output terminal of the second power module being electrically connected to the display screen body, characterized in that, The power supply circuit also includes: A voltage acquisition circuit is electrically connected to the output terminal of the second power module. The voltage acquisition circuit is used to acquire the output voltage of the second power module and output a corresponding voltage acquisition signal. The third power module, wherein the input terminal of the third power module is used to connect to the power supply; The main control circuit is electrically connected to the controlled terminal of the first power module, the output terminal of the voltage acquisition circuit, and the output terminal of the third power module, respectively. The third power module is used to convert the power supply and output it to the main control circuit to power the main control circuit. The main control circuit is used to control the first power module to restart when an abnormality is detected in the output of the second power module based on the voltage acquisition signal. The second power module automatically restarts when the first power module restarts and restores its output voltage.

2. The power supply circuit as described in claim 1, characterized in that, The voltage acquisition circuit includes: A voltage divider circuit is provided, wherein the input terminal of the voltage divider circuit is connected to the output terminal of the second power module, and the output terminal of the voltage divider circuit is electrically connected to the main control circuit.

3. The power supply circuit as described in claim 2, characterized in that, The voltage divider circuit includes: A first resistor and a second resistor, wherein the first end of the first resistor is connected to the output terminal of the second power module, the second end of the first resistor is connected to the first end of the second resistor, the second end of the second resistor is grounded, and the first end of the second resistor is also electrically connected to the main control circuit.

4. The power supply circuit as described in any one of claims 1 to 3, characterized in that, The power supply circuit also includes: The circuit includes a filter circuit and an amplifier circuit. The input terminal of the amplifier circuit is connected to the output terminal of the voltage acquisition circuit, the output terminal of the amplifier circuit is connected to the input terminal of the filter circuit, and the output terminal of the filter circuit is electrically connected to the main control circuit.

5. The power supply circuit as described in claim 4, characterized in that, The filtering circuit includes: A third resistor and a first capacitor are connected, with the first end of the third resistor connected to the output terminal of the amplifier circuit, the second end of the third resistor electrically connected to the first end of the first capacitor and the main control circuit, and the second end of the first capacitor grounded.

6. The power supply circuit as described in claim 4, characterized in that, The amplifier circuit includes: An operational amplifier, a fourth resistor, and a fifth resistor are provided. The first end of the fourth resistor is connected to the output terminal of the voltage acquisition circuit, the second end of the fourth resistor is connected to the first end of the fifth resistor, the first end of the fifth resistor is also connected to the inverting input of the operational amplifier, the output terminal of the operational amplifier is connected to the input terminal of the filter circuit and the second end of the fifth resistor, and the non-inverting input of the operational amplifier is grounded.

7. A display screen, characterized in that, It includes a display screen body and a power supply circuit as described in any one of claims 1 to 6; the display screen body is electrically connected to the power supply circuit.

8. The display screen as described in claim 7, characterized in that, The display screen also includes: The communication module is electrically connected to the output terminals of the main control circuit and the third power supply module, respectively, and is used to establish a communication connection with an external terminal.

9. The display screen as described in claim 7, characterized in that, The display screen also includes: The backlight switch has a first power output terminal and a second power output terminal. The first power output terminal is electrically connected to the display screen body. The input terminal of the backlight switch is connected to the second power output terminal. The output terminal of the backlight switch is electrically connected to the display screen body. The controlled terminal of the backlight switch is electrically connected to the main control circuit.

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