Display screen power supply circuit and split display equipment

Abstract

The embodiment of the invention relates to a display screen power supply circuit and split display equipment, the circuit comprises a first power supply module, a second power supply module and a backlight driving module, the second power supply module and the backlight driving module are arranged on a display screen, the first power supply module is arranged outside the display screen, and the second power supply module is arranged outside the display screen. The second power supply module is used for receiving feedback voltage of the backlight driving module and outputting corresponding backlight compensation voltage based on the feedback voltage; the first power supply module is used for generating an initial backlight driving voltage, superposing the backlight compensation voltage and the initial backlight driving voltage to obtain a backlight driving voltage, and outputting the backlight driving voltage to the backlight driving module. According to the embodiment of the invention, high-power and large-size devices do not need to be used, so that the size of a power supply on the screen is reduced, the thickness of the display screen is reduced, meanwhile, the complexity of a power supply system is reduced, and the cost is saved.

Description

Technical Field

[0001] This application relates to the technical field of display panels, and particularly to a power supply circuit for a display screen and a split display device. Background Art

[0002] A split TV separates the display part, signal processing part, and sound system of the TV, and consists of three parts: a TV display terminal, a TV main unit, and a TV speaker, breaking the traditional integrated structure mode of the three in a TV. The design of the split TV is beneficial for making the display screen ultra-thin, even achieving the effect of seamless wall mounting.

[0003] The power supply system of a split TV is more complex than that of a traditional TV, including a main unit power supply and a power supply on the screen. The power supply on the screen not only supplies power to the timing controller (T-CON, Timing Controller) and the main board on the screen, but also needs to drive the backlight, and a large amount of energy conversion needs to be completed. Traditional switching power supplies require devices such as electrolytic capacitors, transformers, and inductors, and these devices are bulky and occupy a large amount of space, resulting in a larger thickness of the display screen. Summary of the Invention

[0004] In view of this, to solve some or all of the above technical problems, embodiments of this application provide a power supply circuit for a display screen and a split display device.

[0005] In a first aspect, embodiments of this application provide a power supply circuit for a display screen. The circuit includes: a first power supply module, a second power supply module, and a backlight driving module. The second power supply module and the backlight driving module are disposed on the display screen, the first power supply module is disposed outside the display screen, the voltage output terminal of the second power supply module is connected to the negative voltage output terminal of the first power supply module, and the positive voltage output terminal of the first power supply module is connected to the backlight driving module; the feedback voltage output terminal of the backlight driving module is connected to the second power supply module; the second power supply module is configured to receive the feedback voltage and output a corresponding backlight compensation voltage based on the feedback voltage; the first power supply module is configured to generate an initial backlight driving voltage, superimpose the backlight compensation voltage on the initial backlight driving voltage to obtain a backlight driving voltage, and output the backlight driving voltage to the backlight driving module.

[0006] In a possible technical solution, the second power supply module includes a reference voltage generating unit and a voltage conversion unit; the reference voltage generating unit is configured to output a fixed reference voltage, and the voltage conversion unit is configured to output a backlight compensation voltage related to the feedback voltage according to the reference voltage and the feedback voltage.

[0007] In a possible technical solution, the voltage conversion unit includes a first resistor, a second resistor, a third resistor, and a fourth resistor; the first resistor, the second resistor, and the third resistor are connected in series, one end of the third resistor is grounded, and the other end is connected to the output end of the reference voltage generation unit; one end of the fourth resistor is connected to the first resistor and the second resistor, and the other end receives a feedback voltage; the other end of the first resistor outputs a backlight compensation voltage.

[0008] In a possible technical solution, the first power supply module includes a rectification and filtering unit, a boost unit, and a buck unit connected in sequence; the rectification and filtering unit is used to convert alternating current into direct current and output the direct current to the boost unit; the boost unit is used to boost the direct current to obtain a first voltage; the buck unit is used to convert the first voltage into an initial backlight driving voltage and superimpose the received backlight compensation voltage on the initial backlight driving voltage to obtain a backlight driving voltage.

[0009] In a possible technical solution, the buck unit includes a first buck sub-unit and a second buck sub-unit, and the first buck sub-unit and the second buck sub-unit respectively receive the first voltage output by the boost unit; the first buck sub-unit is used to step down the first voltage and output a second voltage with a preset function, and the second buck sub-unit is used to step down the first voltage and output an initial backlight driving voltage; the first buck sub-unit further includes a first power supply branch, and the voltage output end of the first power supply branch is connected to the boost unit; the first power supply branch is used to output a first driving voltage required for boosting to the boost unit.

[0010] In a possible technical solution, the first buck sub-unit further includes a second power supply branch; the voltage input end of the second power supply branch is connected to the voltage output end of the first power supply branch, and the voltage output end of the second power supply branch is connected to the second buck sub-unit; the second power supply branch is used to provide a second driving voltage required for bucking to the second buck sub-unit.

[0011] In a second aspect, an embodiment of the present application provides a split display device, which includes: a host and a display screen. The host includes the first power supply module included in the above display screen power supply circuit, and the display screen includes the second power supply module and the backlight driving module included in the display screen power supply circuit; the first power supply module, the second power supply module, and the backlight driving module are connected through a wire harness between the host and the display screen.

[0012] In a possible technical solution, the host further includes a first main board, the display screen further includes a second main board, the first power supply module includes a rectification and filtering unit, a boosting unit, and a bucking unit connected in sequence, and the power supply input end of the first main board is connected to the bucking unit; the bucking unit is configured to output a second voltage to the first main board; the second main board is connected to the first main board through a wire harness, and the second main board receives the second voltage from the first main board; the second power supply module is connected to the second main board, and is configured to receive the second voltage from the second main board, and output a backlight compensation voltage related to the feedback voltage based on the second voltage and the feedback voltage.

[0013] In a possible technical solution, the bucking unit includes a first bucking sub-unit and a second bucking sub-unit. The first bucking sub-unit and the second bucking sub-unit respectively receive the first voltage output by the boosting unit; the first bucking sub-unit is configured to buck the first voltage and output a second voltage, and the second bucking sub-unit is configured to buck the first voltage and output an initial backlight driving voltage; the first bucking sub-unit further includes a first power supply branch; the control end of the first power supply branch is connected to the first main board, and the voltage output end of the first power supply branch is connected to the boosting unit; the first power supply branch is configured to receive the input first control signal from the first main board, and output the first driving voltage required for boosting to the boosting unit according to the first control signal.

[0014] In a possible technical solution, the first bucking sub-unit further includes a second power supply branch; the control end of the second power supply branch is connected to the first main board, the voltage input end of the second power supply branch is connected to the voltage output end of the first power supply branch, and the voltage output end of the second power supply branch is connected to the second bucking sub-unit; the second power supply branch is configured to receive the input second control signal from the first main board, and provide the second driving voltage required for bucking to the second bucking sub-unit according to the second control signal.

[0015] The display power supply circuit and the split display device provided by the embodiments of the present application set the second power supply module and the backlight driving module on the display screen, and set the first power supply module outside the display screen. The backlight driving module outputs a feedback voltage to the second power supply module. Based on the feedback voltage, the second power supply module outputs a corresponding backlight compensation voltage. The initial backlight driving voltage generated by the first power supply module is superimposed on the backlight compensation voltage to obtain a backlight driving voltage, and the backlight driving voltage is output to the backlight driving module to provide a driving voltage for the backlight driving module. The embodiments of the present application realize responding to the feedback voltage output by the backlight driving module on the display screen, outputting the backlight compensation voltage to the first power supply module outside the display screen, and the first power supply module superimposes the backlight compensation voltage and the initial backlight driving voltage to obtain a backlight driving voltage adapted to the voltage required by the actually driven light-emitting units. Compared with the traditional display power supply system, this circuit does not need to set a dedicated step-down circuit in the display screen to supply power to the backlight driving module, and only needs to set a second power supply module capable of outputting the backlight compensation voltage on the display screen, and the voltage value of the backlight compensation voltage output by the second power supply module is relatively low. Therefore, the second power supply module does not need to use high-power and large-volume devices, thereby reducing the volume of the power supply on the screen, helping to reduce the thickness of the display screen, while reducing the complexity of the power supply system and saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings herein are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present application and used together with the specification to explain the principles of the present application.

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. These exemplary illustrations do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements, unless otherwise stated, and the drawings in the figures do not constitute a proportional limitation.

[0019] Figure 1 It is a schematic structural diagram of the display power supply circuit provided by the embodiments of the present application;

[0020] Figure 2 It is a schematic structural diagram of another display power supply circuit provided by the embodiments of the present application;

[0021] Figure 3 It is a schematic structural diagram of yet another display power supply circuit provided by the embodiments of the present application;

[0022] Figure 4 Schematic diagram of another power supply circuit for a display screen provided by an embodiment of the present application;

[0023] Figure 5 Schematic diagram of another power supply circuit for a display screen provided by an embodiment of the present application;

[0024] Figure 6 Schematic diagram of the second buck sub - unit provided by an embodiment of the present application;

[0025] Figure 7 Schematic diagram of a split display device provided by an embodiment of the present application;

[0026] Figure 8 Schematic diagram of another split display device provided by an embodiment of the present application;

[0027] Figure 9 Schematic diagram of another split display device provided by an embodiment of the present application.

[0028] Reference numerals:

[0029] 101 - First power supply module; 1011 - Rectifying and filtering unit; 1012 - Boosting unit; 1013 - Bucking unit; 10131 - First buck sub - unit; 101311 - First power supply branch; 101312 - Second power supply branch; 10132 - Second buck sub - unit; 102 - Second power supply module; 1021 - Reference voltage generating unit; 1022 - Voltage conversion unit; 103 - Backlight driving module; 701 - Host; 7011 - First main board; 702 - Display screen; 7021 - Second main board. Detailed implementation manners

[0030] Now, various exemplary embodiments of the present application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. It should be noted that: Unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present application.

[0031] Those skilled in the art can understand that terms such as "first" and "second" in the embodiments of the present application are only used to distinguish different steps, devices, or modules, etc., without representing any specific technical meaning and without indicating the logical order between them.

[0032] It should also be understood that in this embodiment, "a plurality of" may refer to two or more, and "at least one" may refer to one, two, or more.

[0033] It should also be understood that for any component, data, or structure mentioned in the embodiments of the present application, in the absence of clear definition or contrary indication in the context, it is generally understood as one or more.

[0034] In addition, the term "and / or" in the present application is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in the present application generally represents an "or" relationship between the associated objects before and after.

[0035] It should also be understood that the description of each embodiment in the present application emphasizes the differences between the embodiments, and their similarities can be referred to each other. For the sake of brevity, they will not be elaborated one by one.

[0036] The following description of at least one exemplary embodiment is actually merely illustrative and in no way limits the present application or its application or use.

[0037] Technologies, circuits, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the above technologies, circuits, and devices should be regarded as part of the specification.

[0038] It should be noted that similar reference numerals and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0039] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. For the convenience of understanding the embodiments of the present application, the present application will be described in detail below with reference to the drawings and in combination with the embodiments. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope of protection of the present application.

[0040] In the power system architecture of a traditional split TV, a PFC (Power Factor Correction) circuit is used to boost the voltage after AC rectification to a high voltage of about 380V, and at the same time, a high power factor is achieved. The main power supply generally adopts two drive circuits, namely drive circuit 1 and drive circuit 2, which respectively convert the above 380V high voltage into corresponding voltages through an isolation transformer, and are respectively used to supply power to the main board on the host and convert a DC high voltage to supply power to the power supply on the screen. Drive circuit 2 outputs high-voltage direct current to the power supply on the screen, and the power supply on the screen outputs an adjustable backlight drive voltage according to the voltage fed back by the backlight drive module.

[0041] To reduce the backlight power consumption, the backlight driving module requires an adjustable power supply voltage, which is adjusted to the voltage at which all the light-emitting units just reach the set current. According to the V-I (voltage-current) curve of an LED (Light-Emitting Diode), when the current ranges from 0 mA to 80 mA, the LED voltage will change by 2 - 3 V, denoted as ΔV1. At the same time, considering the voltage drop across the LED connection line, denoted as ΔV2 (generally within 1 V), and the number of series-connected LEDs is denoted as n. Therefore, the power supply needs to output a DC voltage with a variable voltage to supply power to the backlight driving module, and this DC voltage is denoted as ΔV = n * ΔV1 + ΔV2.

[0042] The power supply on the screen needs to convert the input DC voltage into an adjustable voltage through a DC-DC (direct current to direct current) circuit to supply power to the backlight panel. Since the backlight power is relatively high, in order to achieve higher conversion efficiency and reduce the heat generation of the power supply on the screen, the DC-DC circuit generally adopts an LLC circuit, which requires components such as a transformer and electrolytic capacitors. Due to the limitations of their own materials, the volume of these components cannot be reduced, resulting in the inability to further reduce the thickness of the display screen. At the same time, the entire system is very complex and the system cost is high.

[0043] If the power supply on the screen adopts a buck (step-down) circuit to directly step down the DC voltage transmitted by the connection line to supply power to the constant-current backlight, because of the high power and high input voltage, the power devices of the buck circuit need to use large-sized devices and a controller that supports high-voltage input. There are also problems such as the inability to make the power devices thin and heat generation, and the system cost is high.

[0044] Figure 1 FIG. 11 is a schematic structural diagram of a display screen power supply circuit provided by an embodiment of the present application. This circuit is generally applied to various types of display devices, such as liquid crystal TVs, monitors, etc. Specifically, this circuit includes: a first power supply module 101, a second power supply module 102, and a backlight driving module 103. The second power supply module 102 and the backlight driving module 103 are disposed on the display screen, and the first power supply module 101 is disposed outside the display screen.

[0045] The voltage output terminal of the second power supply module 102 is connected to the negative voltage output terminal of the first power supply module 101, and the positive voltage output terminal of the first power supply module 101 is connected to the backlight driving module 103. Among them, the negative voltage output terminal may be the floating ground terminal included in the first power supply module 101.

[0046] The feedback voltage output terminal of the backlight driving module 103 is connected to the second power supply module 102. The feedback voltage output terminal can output a feedback voltage Vfb (usually in the voltage range of 0 - 2.5V) to the second power supply module 102, and the feedback voltage represents the voltage actually output by the backlight driving module 103.

[0047] The second power supply module 102 is configured to receive the feedback voltage and output a corresponding backlight compensation voltage ΔV based on the feedback voltage.

[0048] The second power supply module 102 can respond to the feedback voltage Vfb and output different backlight compensation voltages according to the change of the feedback voltage Vfb. For example, the second power supply module 102 may include components such as an operational amplifier and a resistor to form an operational amplifier circuit, which can receive the input feedback voltage and perform voltage ratio scaling on the basis of the feedback voltage to obtain the backlight compensation voltage.

[0049] The first power supply module 101 is configured to generate an initial backlight driving voltage, superimpose the backlight compensation voltage and the initial backlight driving voltage to obtain a backlight driving voltage Vout, and output the backlight driving voltage Vout to the backlight driving module 103.

[0050] The first power supply module 101 can output a fixed DC voltage required by the backlight driving module 103. Since the voltage output terminal of the second power supply module 102 is connected to the negative voltage output terminal of the first power supply module 101, the backlight driving voltage output by the first power supply module 101 can be lifted by a certain amplitude on the basis of the initial backlight driving voltage Vout, and the lifted voltage amplitude is the backlight compensation voltage ΔV. Thus, an adjustable backlight driving voltage related to the feedback voltage is provided to the backlight driving module 103.

[0051] The display power supply circuit provided by the embodiment of the present application sets the second power supply module and the backlight driving module on the display screen, sets the first power supply module outside the display screen, the backlight driving module outputs a feedback voltage to the second power supply module, and the second power supply module outputs a corresponding backlight compensation voltage based on the feedback voltage. The initial backlight driving voltage generated by the first power supply module is superimposed on the backlight compensation voltage to obtain a backlight driving voltage, and the backlight driving voltage is output to the backlight driving module to provide a driving voltage for the backlight driving module. The embodiment of the present application realizes the response to the feedback voltage output by the backlight driving module on the display screen, outputs the backlight compensation voltage to the first power supply module outside the display screen, and the first power supply module superimposes the backlight compensation voltage and the initial backlight driving voltage to obtain a backlight driving voltage adapted to the voltage required by the actually driven light-emitting unit. Compared with the traditional display power supply system, this circuit does not need to set a dedicated buck circuit in the display screen to supply power to the backlight driving module, only needs to set a second power supply module on the display screen that can output the backlight compensation voltage, and the voltage value of the backlight compensation voltage output by the second power supply module is relatively low. Therefore, the second power supply module does not need to use high-power and large-volume devices, thereby reducing the volume of the on-screen power supply, helping to reduce the thickness of the display screen, while reducing the complexity of the power supply system and saving costs.

[0052] In some optional implementation manners of this embodiment, as Figure 2 shown, the second power supply module 102 includes a reference voltage generation unit 1021 and a voltage conversion unit 1022.

[0053] The reference voltage generation unit 1021 is used to output a fixed reference voltage Vref, and the voltage conversion unit 1022 is used to output a backlight compensation voltage related to the feedback voltage Vfb according to the reference voltage Vref and the feedback voltage Vfb.

[0054] Among them, the reference power generation unit can be composed of a DC-DC conversion circuit, that is, a fixed voltage is accessed from other components (such as the main board) in the display screen, and this voltage is converted into a reference voltage with another fixed voltage value. For example, the reference voltage generation unit 1021 can be a DC voltage conversion chip.

[0055] The voltage conversion unit 1022 can further linearly combine and superimpose the reference voltage and the feedback voltage to output a backlight compensation voltage that changes with the feedback voltage. For example, the voltage conversion unit 1022 can include an operational amplifier circuit, which can perform operational amplification on the reference voltage and the feedback voltage to output the backlight compensation voltage.

[0056] In this embodiment, by providing a reference voltage generation unit and a voltage conversion unit, the feedback voltage is responded to in the display screen, and only low-power devices are required for the reference voltage generation unit and the voltage conversion unit. These devices are small in size, thus helping to reduce the thickness of the display screen.

[0057] In some alternative implementation manners of this embodiment, as Figure 3 shown, the voltage conversion unit 1022 includes a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4.

[0058] The first resistor R1, the second resistor R2, and the third resistor R3 are connected in series. One end of the third resistor R3 is grounded, and the other end is connected to the output end of the reference voltage generation unit 1021. One end of the fourth resistor R4 is connected to the first resistor R1 and the second resistor R2, and the other end receives the feedback voltage Vfb. The other end of the first resistor R1 outputs the backlight compensation voltage ΔV.

[0059] Based on this circuit, the backlight compensation voltage ΔV is as shown in the following formula (1):

[0060] ΔV = Vref + Vref / R3 * R2 + R1 * ((Vref * (R2 + R3) / (R3 * R4) - VFB / R4 + Vref / R3)

[0061] where Vref is the reference voltage, Vfb is the feedback voltage, Vref / R3 * R2 is the voltage across R2, and R1 * ((Vref * (R2 + R3) / (R3 * R4) - VFB / R4 + Vref / R3) is the voltage across R3. By adjusting the resistance values of each resistor, the required backlight compensation voltage can be obtained.

[0062] In this embodiment, by using resistors to form a voltage conversion unit, a linear conversion of the feedback voltage is achieved. The structure of this voltage conversion unit is simple and stable, which is beneficial to further reducing the volume of the power supply on the screen and reducing the cost of circuit implementation.

[0063] In some alternative implementation manners of this embodiment, as Figure 4 shown, the first power supply module 101 includes a rectification and filtering unit 1011, a boosting unit 1012, and a bucking unit 1013 that are connected in sequence.

[0064] The rectification and filtering unit 1011 is used to convert alternating current into direct current and output the direct current to the boosting unit 1012. As Figure 4 shown, AC is the input alternating current.

[0065] The boost unit 1012 is used to boost the direct current to obtain a first voltage V1. The boost unit 1012 can be implemented by a PFC circuit, and the voltage value of the first voltage V1 is usually 380V direct current.

[0066] The buck unit 1013 is used to convert the first voltage V1 into the initial backlight driving voltage, and superimpose the received backlight compensation voltage on the initial backlight driving voltage to obtain the backlight driving voltage.

[0067] The buck unit 1013 can step down the first voltage V1 to obtain the initial backlight driving voltage required to drive the backlight panel. The buck unit 1013 can superimpose the backlight compensation voltage on the initial backlight driving voltage and output the backlight driving voltage to the backlight driving module 103. For example, the buck unit 1013 includes a floating ground terminal, which is connected to the voltage output terminal of the second power supply module 102, so as to realize the superposition of the initial backlight driving voltage and the backlight compensation voltage.

[0068] In this embodiment, by setting the rectification and filtering unit, the boost unit and the buck unit, outside the display screen, the backlight compensation voltage is superimposed on the initial backlight driving voltage required to generate the backlight driving module, and a backlight driving voltage matching the actual light emission situation of the backlight panel is provided to the backlight driving module, that is, the backlight driving voltage is generated outside the display screen, which helps to simplify the internal power supply structure of the display screen, and helps to reduce the power consumption, cost and thickness of the display screen.

[0069] In some optional implementation manners of this embodiment, as Figure 5 shown, the buck unit 1013 includes a first buck sub-unit 10131 and a second buck sub-unit 10132, and the first buck sub-unit 10131 and the second buck sub-unit 10132 respectively receive the first voltage V1 output by the boost unit 1012.

[0070] The first buck sub-unit 10131 is used to step down the first voltage and output a second voltage V2 with a preset function. Among them, the second voltage V2 can be set according to actual needs. For example, the second voltage V2 can include a 12V voltage required by the main board and a 20V power amplifier voltage, etc.

[0071] The second buck sub-unit 10132 is used to step down the first voltage V1 and output the initial backlight driving voltage. As Figure 6 shown, the second buck sub-unit 10132 can implement the buck function through an LLC circuit and output the initial backlight driving voltage through a coil. One end of the coil of the second buck sub-unit 10132 can be used as the negative voltage output terminal to receive the backlight compensation voltage, raise the initial backlight driving voltage by a certain amplitude, and output the backlight driving voltage.

[0072] As Figure 5 shown, the first step-down sub-unit 10131 further includes a first power supply branch 101311, and the voltage output terminal of the first power supply branch 101311 is connected to the boost unit 1012. The first power supply branch 101311 can be realized by winding out from the primary transformer auxiliary coil of the first step-down sub-unit 10131. The first power supply branch 101311 is used to output a first driving voltage Vd1 required for boosting to the boost unit 1012. For example, if the boost unit 1012 is realized by a PFC circuit, this first driving voltage can be the VCC voltage, which is used to supply power to components such as chips in the boost unit 1012.

[0073] In this embodiment, by setting the first step-down sub-unit and the second step-down sub-unit, and the first step-down sub-unit provides the first driving voltage to the boost unit, it can help to realize multiple voltage outputs in the first power supply module and control the boost unit, improving the flexibility of the display power supply.

[0074] In some optional implementation manners of this embodiment, as Figure 5 shown, the first step-down sub-unit 10131 further includes a second power supply branch 101312.

[0075] The voltage input terminal of the second power supply branch 101312 is connected to the voltage output terminal of the first power supply branch 101311. The second power supply branch 101312 converts the voltage output by the first power supply branch 101311 or directly outputs the voltage output by the first power supply branch 101311. The voltage output terminal of the second power supply branch 101312 is connected to the second step-down sub-unit 10132, and the second power supply branch 101312 is used to provide a second driving voltage Vd2 required for step-down to the second step-down sub-unit 10132. For example, if the second step-down sub-unit 10132 is realized by an LLC circuit, this second driving voltage can be the VCC voltage, which is used for the switching elements in the second step-down sub-unit 10132.

[0076] In this embodiment, by setting the second power supply branch and the second power supply branch provides the second driving voltage to the second step-down sub-unit, it can help to control the second step-down sub-unit and improve the flexibility of the display power supply.

[0077] Figure 7 This is a schematic structural diagram of a split display device provided by an embodiment of the present application, as Figure 7As shown in the figure, the split display device specifically includes: a host 701 and a display screen 702. The host 701 includes a first power supply module 101 included in the above-mentioned display screen power supply circuit, and the display screen includes a second power supply module 102 and a backlight driving module 103 included in the above-mentioned display screen power supply circuit.

[0078] The first power supply module 101, the second power supply module 102, and the backlight driving module 103 are connected by a wire harness between the host 701 and the display screen 702.

[0079] The display screen 702 may further include components such as a backlight panel, a liquid crystal panel, and a timing controller (T-CON). A light-emitting unit array (such as a Mini-LED array) is provided on the backlight panel, and the light-emitting unit array emits light under the drive of the backlight driving module 103. The timing controller can receive image data from the host 701, combine with the backlight driving module 103, and drive the liquid crystal panel to display an image. The host 701 also includes components such as a main board and a speaker, which are used to provide image data to the display screen 702 for display and play audio.

[0080] The split display device provided by the embodiment of the present application, by applying the above-mentioned display screen power supply circuit, realizes responding to the feedback voltage output by the backlight driving module on the display screen, outputting the backlight compensation voltage to the first power supply module outside the display screen, and the first power supply module superimposes the backlight compensation voltage and the initial backlight driving voltage to obtain a backlight driving voltage adapted to the voltage required by the actually driven light-emitting units. Compared with the traditional display screen power supply system, the split display device provided by the present application does not need to set a dedicated step-down circuit in the display screen to supply power to the backlight driving module. Only a second power supply module capable of outputting a backlight compensation voltage needs to be set on the display screen, and the voltage value of the backlight compensation voltage output by the second power supply module is relatively low. Therefore, the second power supply module does not need to use high-power and large-volume devices, thereby reducing the volume of the power supply on the screen, helping to reduce the thickness of the display screen, while reducing the complexity of the power supply system and saving costs.

[0081] In some optional implementation manners of this embodiment, as Figure 8 shown, the host 701 further includes a first main board 7011, the display screen 702 further includes a second main board 7021, the first power supply module 101 includes a rectifying and filtering unit 1011, a boosting unit 1012, and a bucking unit 1013 connected in sequence, and the power supply input end of the first main board is connected to the bucking unit 1013. For the description of the rectifying and filtering unit 1011, the boosting unit 1012, and the bucking unit 1013, reference can be made to the above Figure 4 corresponding embodiment, which will not be elaborated here.

[0082] The step-down unit 1013 is configured to output a second voltage V2 to the first main board. As an example, the second voltage may include a 12V voltage required by the main board, a 20V power amplifier voltage, etc.

[0083] The second main board is connected to the first main board through the wire harness, and the second main board receives the second voltage from the first main board. The second main board can use the received second voltage to supply power to the components on the display screen 702. The second main board can also be connected to the backlight driving module 103 and control the backlight driving module 103 through an SPI signal as Figure 8 shown.

[0084] The second power supply module 102 is connected to the second main board, and is configured to receive the second voltage from the second main board, and output a backlight compensation voltage related to the feedback voltage based on the second voltage and the feedback voltage.

[0085] The second power supply module 102 can convert the second voltage V2 to obtain a converted voltage with a fixed voltage value, and then respond to the feedback voltage, linearly superimpose the feedback voltage and the above-mentioned converted voltage to obtain the backlight compensation voltage. For example, the second power supply module 102 may include a step-down circuit, which receives an input 20V DC voltage, further steps down the 20V voltage to obtain the above-mentioned fixed converted voltage.

[0086] In this embodiment, the step-down unit supplies power to the first main board in the host, the first main board supplies power to the second main board, and the second power supply module receives the second voltage from the second main board. The second power supply module performs voltage conversion on the second voltage with a lower voltage value to obtain the backlight compensation voltage. The second power supply module does not need to perform voltage conversion on high voltage and does not need to use large-power and large-volume devices, thereby helping to reduce the thickness of the display screen 702.

[0087] In some optional implementation manners of this embodiment, as Figure 9 shown, the step-down unit 1013 includes a first step-down subunit 10131 and a second step-down subunit 10132. The first step-down subunit 10131 and the second step-down subunit 10132 respectively receive the first voltage output by the boost unit 1012.

[0088] The first step-down subunit 10131 is configured to step down the first voltage and output the above-mentioned second voltage V2. The second step-down subunit 10132 is configured to step down the first voltage and output the initial backlight driving voltage. For the description of the first step-down subunit 10131 and the second step-down subunit 10132, reference may be made to the corresponding Figure 5 embodiment above, which will not be elaborated here.

[0089] The first step-down subunit 10131 further includes a first power supply branch 101311. The control end of the first power supply branch 101311 is connected to the first main board, and the voltage output end of the first power supply branch 101311 is connected to the boost unit 1012.

[0090] The first power supply branch 101311 is configured to receive an input first control signal S1 from the first main board, and output a first driving voltage Vd1 required for boosting to the boost unit 1012 according to the first control signal.

[0091] For example, if the boost unit 1012 is implemented by a PFC circuit, the first driving voltage Vd1 may be the VCC voltage, which is used to supply power to components such as chips in the boost unit 1012. The first main board can send a first control signal to the first power supply branch 101311, and the first power supply branch 101311 outputs the first driving voltage Vd1 to the boost unit 1012 or stops outputting the first driving voltage Vd1 according to the first control signal. For example, when the first control signal is "1", the first power supply branch 101311 starts and outputs the first driving voltage Vd1 to the boost unit 1012; when the first control signal is "0", the first power supply branch 101311 is turned off and no longer outputs the first driving voltage Vd1 to the boost unit 1012.

[0092] In one example, when the user controls the host 701 to be turned off, the first main board can send "0" to the first power supply branch 101311, the first power supply branch 101311 stops outputting the first driving voltage Vd1, the boost unit 1012 stops working, and the overall device stops power supply.

[0093] In this embodiment, by setting the first step-down subunit and the second step-down subunit, and controlling the first power supply branch by the first main board to provide the first driving voltage to the boost unit, it can help the first power supply module to achieve multiple voltage outputs and control the boost unit, improving the flexibility of device power supply control.

[0094] In some alternative implementation manners of this embodiment, as Figure 9 shown, the first step-down subunit 10131 further includes a second power supply branch 101312.

[0095] The control end of the second power supply branch 101312 is connected to the first main board, the voltage input end of the second power supply branch 101312 is connected to the voltage output end of the first power supply branch 101311, and the voltage output end of the second power supply branch 101312 is connected to the second step-down subunit 10132.

[0096] The second power supply branch 101312 is used to receive the input second control signal S2 from the first main board, and according to the second control signal S2, provide the second driving voltage Vd2 required for bucking to the second bucking sub-unit 10132.

[0097] For example, if the second bucking sub-unit 10132 is implemented by an LLC circuit, the second driving voltage Vd2 can be the VCC voltage, which is used to supply power to components such as chips in the second bucking sub-unit 10132. The first main board can send a second control signal to the second power supply branch 101312, and the second power supply branch 101312 outputs the second driving voltage Vd2 or stops outputting the second driving voltage Vd2 to the second bucking sub-unit 10132 according to the second control signal. For example, when the second control signal is "1", the second power supply branch 101312 starts and outputs the second driving voltage Vd2 to the second bucking sub-unit 10132; when the second control signal is "0", the second power supply branch 101312 is turned off and no longer outputs the second driving voltage Vd2 to the second bucking sub-unit 10132.

[0098] In one example, when the user controls the display screen 702 to turn off, the first main board can send "0" to the second power supply branch 101312. The second power supply branch 101312 stops outputting the second driving voltage Vd2, the second bucking sub-unit 10132 stops working, and the backlight of the display screen 702 is turned off to achieve low-power standby.

[0099] In this embodiment, by setting that the first main board controls the second power supply branch to provide the second driving voltage to the second bucking sub-unit, it can help to flexibly control the turning on and off of the backlight, improve the flexibility of the device power supply control, and help to reduce power consumption.

[0100] Those skilled in the art should also be able to further realize that the units and algorithm steps of each example described in combination with the embodiments disclosed in this article can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different circuits to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0101] The steps of the circuits or algorithms described in connection with the embodiments disclosed herein may be implemented in hardware, software modules executed by a processor, or a combination of both. The software modules may be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium well known in the art.

[0102] It should be understood that the terms used herein are for the purpose of describing particular example embodiments only and are not intended to be limiting. Unless the context clearly dictates otherwise, the singular forms "a", "an", and "the" as used herein may also include the plural forms. The terms "comprising", "including", "containing", and "having" are inclusive and thus specify the presence of the stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The steps, processes, and operations described herein are not to be construed as necessarily requiring them to be performed in the particular order described or illustrated, unless the order of performance is explicitly stated. It should also be understood that additional or alternative steps may be used.

[0103] The above are only specific embodiments of the present application, which enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A display screen power supply circuit, characterized in that: The circuit comprises: a first power supply module, a second power supply module and a backlight driving module, wherein the second power supply module and the backlight driving module are arranged on the display screen, the first power supply module is arranged outside the display screen, the voltage output end of the second power supply module is connected to the voltage output negative end of the first power supply module, and the voltage output positive end of the first power supply module is connected to the backlight driving module; The feedback voltage output terminal of the backlight driving module is connected to the second power supply module; The second power supply module is used to receive the feedback voltage and output a corresponding backlight compensation voltage based on the feedback voltage; The first power supply module is used to generate an initial backlight driving voltage, superimpose the backlight compensation voltage on the initial backlight driving voltage to obtain a backlight driving voltage, and output the backlight driving voltage to the backlight driving module.

2. The circuit according to claim 1, characterized in that The second power supply module includes a reference voltage generating unit and a voltage converting unit; The reference voltage generating unit is used to output a fixed reference voltage, and the voltage converting unit is used to output a backlight compensation voltage related to the feedback voltage according to the reference voltage and the feedback voltage.

3. The circuit according to claim 2, characterized in that The voltage conversion unit includes a first resistor, a second resistor, a third resistor and a fourth resistor; The first resistor, the second resistor and the third resistor are connected in series, one end of the third resistor is grounded, and the other end is connected to the output end of the reference voltage generating unit; One end of the fourth resistor is connected to the first resistor and the second resistor, and the other end receives the feedback voltage; The other end of the first resistor outputs the backlight compensation voltage.

4. The circuit according to claim 1, characterized in that The first power supply module includes a rectifier and filter unit, a boost unit and a buck unit connected in sequence; The rectifying and filtering unit is used to convert the alternating current into direct current, and output the direct current to the boosting unit; The boost unit is used to boost the direct current to obtain a first voltage; The voltage reduction unit is used for converting the first voltage into the initial backlight driving voltage, and superimposing the received backlight compensation voltage with the initial backlight driving voltage to obtain the backlight driving voltage.

5. The circuit according to claim 4, characterized in that The step-down unit comprises a first step-down subunit and a second step-down subunit, wherein the first step-down subunit and the second step-down subunit respectively receive the first voltage output by the step-up unit; The first step-down subunit is used to step down the first voltage and output a second voltage of a preset function, and the second step-down subunit is used to step down the first voltage and output the initial backlight driving voltage; The first voltage reduction subunit further includes a first power supply branch, and a voltage output end of the first power supply branch is connected to the voltage boost unit; The first power supply branch is used to output a first driving voltage required for boosting to the boost unit.

6. The circuit according to claim 5, characterized in that The first step-down subunit further includes a second power supply branch; The voltage input end of the second power supply branch is connected to the voltage output end of the first power supply branch, and the voltage output end of the second power supply branch is connected to the second step-down sub-unit; The second power supply branch is used to provide the second step-down subunit with a second driving voltage required for step-down.

7. A split display device, characterized in that: The split display device comprises: a host and a display screen, the host comprises a first power supply module included in the display screen power supply circuit according to any one of claims 1 to 6, and the display screen comprises a second power supply module and a backlight driving module included in the display screen power supply circuit; The first power supply module, the second power supply module and the backlight driving module are connected via a wiring harness between the host and the display screen.

8. The split display device according to claim 7, characterized in that: The host further includes a first mainboard, the display screen further includes a second mainboard, the first power supply module includes a rectifier and filter unit, a boost unit and a buck unit connected in sequence, and the power supply input end of the first mainboard is connected to the buck unit; The step-down unit is used to output a second voltage to the first mainboard; The second main board is connected to the first main board through the wiring harness, and the second main board receives the second voltage from the first main board; The second power supply module is connected to the second mainboard, and is used for receiving the second voltage from the second mainboard, and outputting a backlight compensation voltage related to the feedback voltage based on the second voltage and the feedback voltage.

9. The split display device according to claim 8, characterized in that: The step-down unit comprises a first step-down subunit and a second step-down subunit, wherein the first step-down subunit and the second step-down subunit respectively receive the first voltage output by the step-up unit; The first step-down subunit is used to step down the first voltage and output the second voltage, and the second step-down subunit is used to step down the first voltage and output the initial backlight driving voltage; The first step-down subunit further includes a first power supply branch; The control end of the first power supply branch is connected to the first mainboard, and the voltage output end of the first power supply branch is connected to the boost unit; The first power supply branch is used to receive a first control signal input from the first mainboard, and output a first driving voltage required for boosting to the boost unit according to the first control signal.

10. The split display device according to claim 9, characterized in that: The first step-down subunit further includes a second power supply branch; The control end of the second power supply branch is connected to the first mainboard, the voltage input end of the second power supply branch is connected to the voltage output end of the first power supply branch, and the voltage output end of the second power supply branch is connected to the second step-down sub-unit; The second power supply branch is used to receive a second control signal input from the first mainboard, and provide a second driving voltage required for voltage reduction to the second voltage reduction subunit according to the second control signal.

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