CN116994530A

CN116994530A - Display device and power supply module

Info

Publication number: CN116994530A
Application number: CN202310794140.XA
Authority: CN
Inventors: 庞震华; 李斌; 韩文涛
Original assignee: Hisense Visual Technology Co Ltd
Current assignee: Hisense Visual Technology Co Ltd
Priority date: 2023-06-29
Filing date: 2023-06-29
Publication date: 2023-11-03

Abstract

The application provides a display device and a power supply module, comprising: the primary winding unit, the first secondary winding unit and the power supply unit; the primary winding unit is used for outputting a first primary voltage and a second primary voltage in a time-sharing manner; the power supply unit includes: a second secondary winding unit and a voltage adjusting unit; the input end of the voltage adjusting unit is connected with the output end of the first secondary winding unit, the output end of the voltage adjusting unit is connected with the negative electrode output end of the second secondary winding unit, and the voltage adjusting unit is used for carrying out voltage transformation treatment on the first voltage and then outputting the first voltage; the second secondary winding unit is coupled with the primary winding unit, and the positive electrode output end of the second secondary winding unit is connected with the backlight component; the power supply unit is used for outputting a second voltage to the backlight assembly based on the second primary side voltage. The application can improve the adaptive power of the power supply module under the asymmetric half-bridge circuit.

Description

Display device and power supply module

Technical Field

The application relates to the technical field of display equipment, in particular to display equipment and a power supply module.

Background

With the development of electronic technology and internet technology, display devices such as laser televisions and intelligent displays are widely used in daily life of people. The display device is provided with a power supply module for supplying power to the display device, the power consuming components of the display device comprise a main board and a backlight assembly,

In the related art, the power supply module comprises an asymmetric half-bridge circuit, and the asymmetric half-bridge circuit outputs corresponding power supply voltages to the main board and the backlight element respectively through two secondary windings of a transformer in the asymmetric half-bridge circuit, and the asymmetric half-bridge circuit realizes double-path closed-loop output through time-sharing control.

However, in the time-sharing control process, one load power needs to be switched to the other load power, and the two load powers cannot be too different due to the limitation of factors such as the working frequency of the asymmetric half-bridge circuit and the utilization rate of the magnetic core in the transformer, and the power of the main board is relatively stable, so that the power of the backlight element is limited, and the power supply module can only be adapted to the display device with lower power.

Disclosure of Invention

The application provides display equipment and a power supply module, and aims to solve the problem that the adaptive power of the power supply module under an asymmetric half-bridge circuit is low.

In a first aspect, the present application provides a display apparatus, including a backlight assembly, a main board, and a power supply module; the power supply module includes: the primary winding unit, the first secondary winding unit and the power supply unit; the primary winding unit is used for outputting a first primary voltage and a second primary voltage in a time-sharing manner; the first secondary winding unit is coupled to the primary winding unit, and an output end of the first secondary winding unit is connected with the main board and is used for outputting a first voltage to the main board based on the first primary voltage; the power supply unit includes: a second secondary winding unit and a voltage adjusting unit; the input end of the voltage adjusting unit is connected with the output end of the first secondary winding unit, the output end of the voltage adjusting unit is connected with the negative electrode output end of the second secondary winding unit, and the voltage adjusting unit is used for carrying out voltage transformation treatment on the first voltage and then outputting the first voltage; the second secondary winding unit is coupled to the primary winding unit, and the positive output end of the second secondary winding unit is connected with the backlight assembly; the power supply unit is used for outputting a second voltage to the backlight assembly based on the second primary side voltage; the difference between the second voltage and the first voltage is greater than a first threshold.

In some embodiments, the power module further comprises: the output end of the first feedback unit is connected with the first controller, and the first feedback unit is used for outputting a first feedback signal to the first controller based on the first voltage; the second feedback unit is connected with the first controller and is used for outputting a second feedback signal to the first controller; the first controller is connected with the primary winding unit and is used for outputting a first control signal and a second control signal to the output primary winding unit based on the first feedback signal and the second feedback signal so that the primary winding unit controls the first primary voltage and the second primary voltage based on the first control signal and the second control signal; the voltage adjustment unit includes: and the second controller is connected with the third feedback unit and is used for outputting a third feedback signal to the second controller, and the second controller controls the voltage output by the voltage adjusting unit based on the third feedback signal.

In some embodiments, the input end of the second feedback unit is connected to the positive output end of the second secondary winding unit and the negative output end of the second secondary winding unit, and is configured to output the second feedback signal based on a voltage difference between the positive output end of the second secondary winding unit and the negative output end of the second secondary winding unit; the input end of the third feedback unit is connected with the backlight assembly, and is used for sampling the current of the backlight assembly and outputting the third feedback signal based on the current of the backlight assembly.

In some embodiments, an input terminal of the second feedback unit is connected to the backlight assembly, and the second feedback unit is configured to sample a current of the backlight assembly and output the second feedback signal based on the current of the light assembly; the input end of the third feedback unit is connected with the output end of the voltage adjusting unit and is used for outputting a third feedback signal based on the output voltage of the voltage adjusting unit.

In some embodiments, an input terminal of the second feedback unit is connected to an output terminal of the voltage adjustment unit, and is configured to output the second feedback signal based on an output voltage of the voltage adjustment unit; an input end of the third feedback unit is connected with the backlight assembly, and is used for sampling the current of the backlight assembly and outputting the third feedback signal based on the current of the backlight assembly; the feedback speed of the third feedback unit is faster than that of the second feedback unit.

In some embodiments, the second feedback unit includes: the three-terminal voltage regulator comprises a first resistor, a second resistor, a third resistor, a first capacitor, a three-terminal voltage regulator and a photoelectric coupler; one end of the first resistor is connected with the output end of the voltage adjusting unit, and the other end of the first resistor is connected with one end of the second resistor; the other end of the second resistor is grounded; one end of the third resistor is connected with the other end of the first resistor and one end of the second resistor, and the other end of the third resistor is connected with one end of the first capacitor; the other end of the first capacitor is connected with the primary side output end of the photoelectric coupler, and the primary side input end of the photoelectric coupler receives a second reference voltage; the secondary side input end of the photoelectric coupler is connected with the first controller, and the secondary side input end of the photoelectric coupler is grounded; the reference electrode of the three-terminal voltage stabilizer is connected with the other end of the third resistor and one end of the first capacitor, the positive electrode of the three-terminal voltage stabilizer is grounded, and the negative electrode of the three-terminal voltage stabilizer is connected with the primary side output end of the photoelectric coupler.

In some embodiments, the second feedback unit further comprises: one end of the fourth resistor receives the first reference voltage, and the other end of the fourth resistor is connected with the primary side input end of the photoelectric coupler and one end of the fifth resistor; the other end of the fifth resistor is connected with the positive electrode of the three-terminal voltage stabilizer and the primary side output end of the photoelectric coupler.

In some embodiments, the power module further comprises: and one end of the second capacitor is connected with the output end of the voltage adjusting unit, and the other end of one end of the second capacitor is grounded.

In some embodiments, the voltage regulation circuit is a buck conversion circuit or a boost conversion circuit.

In a second aspect, the present application provides a power supply module, comprising: the primary winding unit, the first secondary winding unit and the power supply unit; the primary winding unit is used for outputting a first primary voltage and a second primary voltage in a time-sharing manner; the first secondary winding unit is coupled to the primary winding unit, and an output end of the first secondary winding unit is connected with the main board and is used for outputting a first voltage to the main board based on the first primary voltage; the power supply unit includes: a second secondary winding unit and a voltage adjusting unit; the input end of the voltage adjusting unit is connected with the output end of the first secondary winding unit, the output end of the voltage adjusting unit is connected with the negative electrode output end of the second secondary winding unit, and the voltage adjusting unit is used for carrying out voltage transformation treatment on the first voltage and then outputting the first voltage; the second secondary winding unit is coupled to the primary winding unit, and the positive output end of the second secondary winding unit is connected with the backlight assembly; the power supply unit is used for outputting a second voltage to the backlight assembly based on the second primary side voltage; the difference between the second voltage and the first voltage is greater than a first threshold.

In the display device and the power supply module provided by the application, the first secondary winding unit outputs the first voltage to the main board based on the first primary voltage, the input end of the voltage regulating unit in the power supply unit is connected with the output end of the first secondary winding unit, the output end of the voltage regulating unit is connected with the negative electrode output end of the second secondary winding unit, the voltage regulating unit is used for carrying out voltage transformation treatment on the first voltage and outputting the first voltage, the positive electrode output end of the second secondary winding unit is connected with the backlight assembly, the power supply unit is used for outputting the second voltage to the backlight assembly based on the second primary voltage, and the difference value between the second voltage and the first voltage is larger than the first threshold value. In the scheme, the voltage adjusting unit is connected with the negative electrode output end of the second secondary winding unit, so that the voltage output by the voltage adjusting unit increases the positive electrode output end voltage of the second secondary winding unit, so that the power supply unit can output higher second voltage, and in effect, the voltage adjusting unit is equivalent to transferring part of output power of the first secondary winding unit to the second secondary winding unit so as to increase the output power for supplying power to the backlight, and the output power of the first secondary winding unit and the output power of the second secondary winding unit are not greatly different.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description, serve to explain the principles of the embodiments of the application.

Specific embodiments of the present application have been shown by way of the above drawings and will be described in more detail below. The drawings and the written description are not intended to limit the scope of the inventive embodiments in any way, but rather to illustrate the inventive embodiments by reference to specific embodiments.

Fig. 1 is a schematic structural diagram of a display device provided with an independent power panel according to the present application;

fig. 2 is a schematic diagram of a connection relationship between a power panel and a load provided by the present application;

FIG. 3 is a schematic diagram of a TV power architecture provided by the present application;

fig. 4 is a schematic structural diagram of a display device according to an embodiment of the present application;

FIG. 5 is a schematic diagram of another display device according to an embodiment of the present application;

FIG. 6 is a schematic diagram of a voltage adjusting unit in an example;

fig. 7 is a schematic structural diagram of a display device according to another embodiment of the present application;

fig. 8 is a schematic structural diagram of another display device according to another embodiment of the present application;

Fig. 9 is a schematic structural diagram of still another display device according to another embodiment of the present application;

fig. 10 is a schematic diagram of a structure of a second feedback unit in an example;

fig. 11 is a schematic diagram of the structure of the second feedback unit 112 in an example;

fig. 12 is a schematic diagram of the structure of the third feedback unit 113 in an example.

Specific embodiments of the present application have been shown by way of the above drawings and will be described in more detail below. The drawings and the written description are not intended to limit the scope of the inventive concepts in any way, but rather to illustrate the inventive concepts to those skilled in the art by reference to the specific embodiments.

Detailed Description

Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples do not represent all implementations consistent with the application. Rather, they are merely examples of apparatus and methods consistent with aspects of the application as detailed in the accompanying claims.

It should be noted that the brief description of the terminology in the present application is for the purpose of facilitating understanding of the embodiments described below only and is not intended to limit the embodiments of the present application. Unless otherwise indicated, these terms should be construed in their ordinary and customary meaning.

The terms first, second and the like in the description and in the claims and in the above-described figures are used for distinguishing between similar or similar objects or entities and not necessarily for describing a particular sequential or chronological order, unless otherwise indicated (Unless otherwise indicated). It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application are, for example, capable of operation in sequences other than those illustrated or otherwise described herein.

Furthermore, the terms "comprise" and "have," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a product or apparatus that comprises a list of elements is not necessarily limited to those elements expressly listed, but may include other elements not expressly listed or inherent to such product or apparatus. The term "circuitry" as used in this disclosure refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and/or software code that is capable of performing the function associated with that element.

The following describes the application scenario related to the present application and the problems in the related art.

As the demand for information is increasing, various types of display devices, such as computers, televisions, projectors, and the like, are developing. The power supply circuit is one of the most important circuit structures in the display device, and can provide electric energy for the display device, so that the display device can normally operate. Some display devices are provided with independent power boards, and some display devices integrate the power boards with the main boards.

Taking a display device provided with an independent power panel as an example, the structure of the display device is described, referring to fig. 1, fig. 1 is a schematic structural diagram of the display device provided with the independent power panel, and as shown in fig. 1, the display device includes a panel 1, a backlight assembly 2, a main board 3, a power panel 4, a rear case 5 and a base 6. Wherein the panel 1 is used for presenting pictures to a user; the backlight assembly 2 is located below the panel 1, usually some optical assemblies, and is used for providing enough brightness and uniformly distributed light sources to enable the panel 1 to display images normally, the backlight assembly 2 further comprises a back plate 20, the main plate 3 and the power panel 4 are arranged on the back plate 20, some convex hull structures are usually stamped and formed on the back plate 20, and the main plate 3 and the power panel 4 are fixed on the convex hulls through screws or hooks; the rear shell 5 is arranged on the panel 1 in a covering way so as to hide parts of the display equipment such as the backlight assembly 2, the main board 3, the power panel 4 and the like, thereby having an attractive effect; and a base 6 for supporting the display device.

In some embodiments, fig. 2 is a schematic diagram of connection between a power panel and a load, as shown in fig. 2, the power panel 4 includes an input terminal 41 and an output terminal 42 (a first output terminal 421, a second output terminal 422, and a third output terminal 423 are shown in the figure), where the input terminal 41 is connected to a mains supply, the output terminal 42 is connected to the load, for example, the first output terminal 421 is connected to an LED light bar for lighting a display screen, the second output terminal 422 is connected to an audio board, and the third output terminal 423 is connected to a motherboard. The power panel 4 needs to convert ac mains to dc power required by a load, and the dc power generally has different specifications, for example, 18V for sound, 12V for a panel, and the like.

Specifically, taking a television as an example to describe a power architecture of a display device, fig. 3 is a schematic diagram of the power architecture of the television provided by the present application, and as shown in fig. 3, the display device may include: power module, load, wherein, power module includes: a rectifier bridge, a power factor correction (Power Factor Correction, PFC) module, and a resonant converter (LLC) module, the LLC module including a synchronous rectifier circuit (not shown in fig. 3). The PFC module is connected with the LLC module, the LLC module can be an asymmetric half-bridge circuit, and corresponding power supply voltages are respectively output to the main board and the backlight element through two secondary windings of a transformer (not shown) in the asymmetric half-bridge circuit, and the asymmetric half-bridge circuit realizes double-path closed-loop output through time-sharing control.

In order to solve the above problems, the application provides a voltage adjusting unit connected between the first secondary winding unit and the second secondary winding unit, the voltage adjusting unit performs voltage transformation processing on the first voltage output by the first secondary winding unit and outputs the first voltage, and the output end of the voltage adjusting unit is connected with the negative output end of the second secondary winding unit, so that the voltage output by the voltage adjusting unit increases the positive output end voltage of the second secondary winding unit, so that the power supply unit can output with higher second voltage, which is equivalent to transferring part of the output power of the first secondary winding unit to the second secondary winding unit to increase the output power for supplying power to the backlight.

The technical scheme of the present application and the technical scheme of the present application will be described in detail with specific examples. The following embodiments may be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments. In describing the present application, the terms should be construed broadly in the art unless explicitly stated and limited otherwise. Embodiments of the present application will be described below with reference to the accompanying drawings.

Fig. 4 is a schematic structural diagram of a display device according to an embodiment of the present application, as shown in fig. 4, including: a backlight assembly 60, a main board 50, and a power supply module 10; the power supply module 10 includes: a primary winding unit 110, a first secondary winding unit 120, and a power supply unit;

the primary winding unit 110 is configured to output a first primary voltage and a second primary voltage in a time-sharing manner;

the first secondary winding unit 120 is coupled to the primary winding unit 110, and an output end of the first secondary winding unit 120 is connected to the main board 50 and is configured to output a first voltage to the main board 50 based on the first primary voltage;

the power supply unit includes: a second secondary winding unit 130 and a voltage adjustment unit 140; the input end of the voltage adjusting unit 140 is connected with the output end of the first secondary winding unit 120, the output end of the voltage adjusting unit 140 is connected with the negative output end of the second secondary winding unit 130, and the voltage adjusting unit 140 is used for performing voltage transformation treatment on the first voltage and outputting the first voltage; the second secondary winding unit 130 is coupled to the primary winding unit 110, and the positive output terminal of the second secondary winding unit 130 is connected to the backlight assembly 60; the power supply unit is configured to output a second voltage to the backlight assembly 60 based on the second primary voltage; the difference between the second voltage and the first voltage is greater than a first threshold.

The display device in the present embodiment includes, but is not limited to: electronic devices with display panels such as televisions, cell phones, computers, watches, and augmented reality devices.

The backlight assembly 60 of this embodiment may be of various forms, for example, in a Miniled or micro LED display, the backlight assembly 60 may be a light bar comprising multiple channels carrying micro LED light beads, the multiple channels of light bars comprising multiple backlight partitions. As another example, in a laser television, the backlight assembly 60 may be a red, green, and blue laser. The main board 50 is used to control the operation state of the display device, and a constant supply voltage of 12V is typically required.

The power supply module 10 includes a primary winding unit 110, where the primary winding unit 110 is configured to output a first primary voltage and a second primary voltage in a time-sharing manner, that is, output by using an asymmetric half-bridge technology. As an example, the power supply module 10 may comprise an LLC circuit, while the primary winding unit 110, the first secondary winding unit 120, the second secondary winding unit 130 are part of the LLC circuit, with continued reference to fig. 4, the primary winding unit 110 may comprise a first switching tube V1, a second switching tube V2, a first storage capacitor C1', a primary winding of a transformer; the first secondary winding unit 120 may include: a first secondary winding of the transformer, a first diode VD1 and a second storage capacitor C2'; the second secondary winding unit 130 may include: the second secondary winding of the transformer, the second diode VD2 and the third storage capacitor C3', and the same name ends of the first secondary winding and the second secondary winding are opposite.

When the LLC power supply works, the first controller of the LLC outputs a first control signal and a second control signal to drive the first switching tube V1 and the second switching tube V2, time-sharing conduction of the first switching tube V1 and the second switching tube V2 is realized, the duty ratios of the first control signal and the second control signal are different, namely the conduction time periods of the first switching tube V1 and the second switching tube V2 are different, based on the difference, the respective control of the first primary side voltage and the second primary side voltage can be realized, and for the secondary side, the time-sharing storage electric quantity of the two capacitors is respectively controlled through diodes with different flow directions, and the control of the output voltages of the first secondary side winding unit 120 and the second secondary side winding unit 130 is further realized.

It should be noted that, with continued reference to fig. 4, the power supply module 10 may further include a third secondary winding unit 150, where the third secondary winding unit 150 is used to supply power to the audio component 70 such as a sound device, but the power supply requirement of the audio component 70 is relatively low, and the third secondary winding unit 150 uses open loop power supply, which is not an improvement of this part, so this will not be described in detail in the present disclosure.

In some examples, fig. 5 is a schematic structural diagram of another display device according to an embodiment of the present application, as shown in fig. 5, the power supply module 10 may further include a rectifier bridge circuit 160 and a PFC circuit 170, where the rectifier bridge circuit 160 may be a full-bridge or half-bridge rectifier circuit for rectifying ac mains power into a dc electrical signal; the PFC performs power conversion processing on the dc signal, and outputs a dc signal corresponding to the load to the primary winding unit 110.

In this example, the voltage adjustment unit 140 may be a Buck conversion circuit, such as a Buck circuit; a Boost converter circuit, such as a Boost circuit, is also possible. The operation principle of the voltage adjusting unit 140 is exemplarily described by taking a Buck circuit as an example.

Fig. 6 is a schematic structural diagram of a voltage adjustment unit in an example, as shown in fig. 6, the voltage adjustment unit 140 may include: the second controller, the third switching tube V3, the first inductor L1, the fourth storage capacitor C4', the third diode VD3;

one end of the third switch tube V3 is connected with the output end of the first secondary winding unit 120, one end of the third switch tube V3

The other end of the third switching tube V3 is connected with the cathode of the third diode VD3 and one end of the first inductor L1, and the control end of the third switching tube V3 is connected with the second controller to receive a driving signal; the other end of the first inductor L1 is connected with one end of a fourth storage capacitor C4'; the other end of the fourth storage capacitor C4' is connected to the anode of the third diode VD3 and to the ground.

In operation, with continued reference to fig. 6, the second controller outputs a third control signal, where the third control signal is connected to the control end of the third switching tube V3 to control the on/off of the third switching tube V3, where the third switching tube V3 may be a P-type or N-type MOS tube or a triode. When the third switching tube V3 is turned on, the second capacitor C2 and the first inductor L1 are charged, and when the third switching tube V3 is turned off, the first inductor L1 and the second capacitor C2 are discharged, so that the output voltage can be controlled by controlling the on and off time of the third switching tube V3, that is, the received first voltage VO1 is converted into the third voltage VO3, and the third voltage VO1 is output to the negative terminal of the second secondary winding unit.

In some examples, referring back to fig. 5, the power module 10 may further include: the second capacitance C2 of the first capacitor,

one end of the second capacitor C2 is connected to the output end of the voltage adjusting unit 140, and the other end of the second capacitor C2 is grounded. The second capacitor C2 is a filter capacitor, and is used for reducing the influence of factors such as radiation interference on the voltage adjustment unit 140.

The present embodiment will be exemplarily described below in connection with actual scenarios: as shown in fig. 4 and 5, since the main board 50 is supplied with power at a constant voltage, the first voltage is 12V, and the load of the second sub-winding unit 130 is set to not more than 100W, taking the main board 50 power of 36W and the backlight assembly 60 150W as an example. The voltage adjusting unit 140 receives the first voltage of 12V and converts the second voltage into the third voltage, and when in actual operation, the backlight assembly 60 needs constant current power supply, the required current is 5A based on the current brightness requirement, in which case the required voltage of the backlight assembly 60 is 30V; the upper limit value of the fourth voltage outputted from the second secondary winding unit 130 is 20V, and the voltage adjusting unit 140 converts the voltage of 12V into 10V and outputs the 10V to the negative output terminal of the second secondary winding unit 130, so that the fourth voltage and the third voltage are superimposed to obtain the second voltage of 30V. It can be understood that the voltage adjusting unit 140 and the second secondary winding unit 130 correspond to two power sources connected in series to jointly supply power to the backlight assembly 60 at this time; for the first secondary winding unit 120, the voltage adjusting unit 140 corresponds to a load parallel to the motherboard 50, and the first secondary winding unit 120 needs to provide 36w+50w of power, that is, the voltage adjusting unit 140 transfers part of the output power of the first secondary winding unit 120 to balance the output power of the first secondary winding unit 120, so as to improve the power supply power for supplying power to the backlight without increasing the output power of the first secondary winding unit 120.

It should be further noted that, based on the above example, the power of the main board 50 and the power of the backlight assembly 60 may be represented by the first voltage and the second voltage, so that the limiting values of the two powers may be represented by the difference between the first voltage and the second voltage, so that the difference between the second voltage and the first voltage is greater than the first threshold in this embodiment, it may be understood that the present example can realize that the upper limit value can be detected between the power of the backlight assembly 60 and the power of the main board 50.

To further improve the reliability of the power supply module 10, it is also necessary to control each output voltage based on a feedback circuit to realize constant voltage power supply of the main board 50 and constant current power supply of the backlight assembly 60.

In some examples, fig. 7 is a schematic structural diagram of a display device according to another embodiment of the present application, and as shown in fig. 7, the power supply module 10 further includes: a first feedback unit 111, a second feedback unit 112, and a first controller;

the input end of the first feedback unit 111 is connected with the output end of the first secondary winding unit 120, the output end of the first feedback unit 111 is connected with the first controller, and the first feedback unit 111 is used for outputting a first feedback signal to the first controller based on the first voltage;

The second feedback unit 112 is connected to the first controller, and is configured to output a second feedback signal to the first controller;

the first controller is connected to the primary winding unit 110, and is configured to output a first control signal and a second control signal to the output primary winding unit 110 based on the first feedback signal and the second feedback signal, so that the primary winding unit 110 controls the first primary voltage and the second primary voltage based on the first control signal and the second control signal.

In this example, the first feedback unit 111 samples a first voltage and generates a first feedback signal based on the first voltage to control the first secondary winding unit 120 to output a constant voltage. The second feedback unit 112 is used for controlling the fourth voltage output by the first secondary winding unit 120. In combination with the example in fig. 5, the first controller may generate the first control signal and the second control signal based on the first feedback signal and the second feedback signal, and output the first control signal and the second control signal to the first switching tube V1 and the second switching tube V2, respectively, so as to control the first primary voltage and the second primary voltage by controlling the switching time periods of the first switching tube V1 and the second switching tube V2, and further control the first voltage and the second voltage output by the two windings.

Illustratively, with continued reference to fig. 7, the above-described method may further include: and a third feedback unit 113 connected to the second controller of the voltage adjustment unit 140, for outputting a third feedback signal to the second controller to control the third voltage output by the voltage adjustment unit 140.

The constant voltage output of the first secondary winding unit 120 may be realized based on the above-described first feedback unit 111. The constant current power supply of the backlight assembly 60 may be implemented based on the second feedback unit 112 and the second feedback unit 112, and specific implementations may include various ones, which will be exemplarily described below.

In some examples, as shown in fig. 7, an input terminal of the second feedback unit 112 is connected to the backlight assembly 60, and the second feedback unit 112 is configured to sample a current of the backlight assembly 60 and output a second feedback signal based on the current of the light assembly;

an input terminal of the third feedback unit 113 is connected to an output terminal of the voltage adjustment unit 140, and is configured to output a third feedback signal based on an output voltage of the voltage adjustment unit 140;

in this example, the second feedback unit 112 samples the current of the backlight assembly 60 and outputs a second feedback signal to the first controller based on the backlight current, the first controller compares the second feedback signal with a reference value corresponding to the reference current, outputs a corresponding control signal based on the comparison result to control the fourth voltage output by the second sub-winding unit 130, and makes the current of the backlight assembly 60 be a predetermined reference current through adjustment of the fourth voltage.

With continued reference to fig. 7, the third feedback unit 113 samples the third voltage output by the voltage adjustment unit 140, and outputs a third feedback signal to the second controller based on the sampled third voltage, and the second controller compares the third feedback signal with a reference value corresponding to the second reference voltage, and controls the third voltage output by the voltage adjustment unit 140 to be the second reference voltage based on the comparison result.

It can be understood that the voltage adjusting unit 140 in this example outputs a constant voltage, and adjusts the fluctuation of the current of the backlight assembly 60 by the output voltage of the second secondary winding unit 130, so that the second feedback unit 112 and the third feedback unit 113 provided based on this example can realize constant current supply of the backlight assembly 60.

In another embodiment, fig. 8 is a schematic structural diagram of another display device according to another embodiment of the present application, as shown in fig. 8, a second feedback unit 112 connected to the positive output terminal of the second secondary winding unit 130 and the negative output terminal of the second secondary winding unit 130, for outputting a second feedback signal based on a voltage difference between the positive output terminal of the second secondary winding unit 130 and the negative output terminal of the second secondary winding unit 130;

And a third feedback unit 113 connected to the backlight assembly 60 for sampling a current of the backlight assembly 60 and outputting a third feedback signal based on the current of the backlight assembly 60.

In this example, the voltage difference between the positive output end and the negative output end of the second secondary winding unit 130 is the fourth voltage output by the second secondary winding unit 130, the third feedback unit 113 samples the fourth voltage, and outputs a second feedback signal to the first controller based on the fourth voltage, the first controller compares the second feedback signal with a reference value corresponding to the first reference voltage, and outputs a corresponding control signal based on the comparison result to control the fourth voltage to be equal to the first reference voltage, so that it can be known that in this embodiment, the second secondary winding unit 130 is controlled to output a constant fourth voltage.

With continued reference to fig. 8, the third feedback unit 113 outputs a third feedback signal to the second controller based on the current of the backlight assembly 60, the second controller compares the third feedback signal with a reference value corresponding to the reference current, and outputs a third control signal based on the comparison result to control the voltage adjusting unit 140 to output a corresponding third voltage, and controls the current of the backlight assembly 60 based on the third voltage as the reference current.

That is, the second sub-winding unit 130 in this example outputs a constant voltage, and the current of the backlight assembly 60 is adjusted by the voltage adjusting unit 140 to achieve constant current supply of the backlight assembly 60. It should be noted that, for the asymmetric half-bridge circuit, the first secondary winding unit 120 and the second secondary winding unit 130 are associated with each other, and one of the two secondary winding units fluctuates to cause the other to shake during the fast response, and the independent voltage adjustment unit 140 in this example is used to correspondingly fluctuate the backlight, so that the stability of the asymmetric half-bridge circuit is improved, and the stability of the power-suppliable module 10 is further improved.

In still other examples, fig. 9 is a schematic structural diagram of still another display device according to another embodiment of the present application, as shown in fig. 9,

the input end of the second feedback unit 112 is connected to the output end of the voltage adjustment unit 140, and is configured to output a second feedback signal based on the output voltage of the voltage adjustment unit 140;

an input terminal of the third feedback unit 113 is connected to the backlight assembly 60, for sampling a current of the backlight assembly 60, and outputting a third feedback signal based on the current of the backlight assembly 60;

the feedback speed of the third feedback unit 113 is faster than that of the second feedback unit 112.

In this example, the third feedback unit 113 samples the current of the backlight assembly 60 and gives the current to output a third feedback signal to the second controller, similar to the second feedback unit 112 in the above example, and the second controller implements control of the third voltage output from the voltage adjustment unit 140 based on the third feedback signal, thereby implementing constant current supply of the backlight current.

With continued reference to fig. 9, the second feedback unit 112 samples the third voltage output by the voltage adjustment unit, generates a third feedback signal based on the output voltage to the first controller, compares the third feedback signal with a reference value corresponding to the third reference voltage, and outputs a corresponding control signal based on the comparison result to control the third voltage output by the voltage adjustment unit to be the third reference voltage. Wherein the feedback speed of the third feedback unit 113 is faster than the feedback speed of the second feedback unit 112, that is, in this example. When the current of the backlight assembly 60 fluctuates, the adjustment is performed by the voltage adjustment module first, and then the adjustment is performed by the second secondary winding unit 130.

For example, when the voltage adjusting unit 140 detects that the current of the backlight assembly 60 is lower than the reference current through the third feedback unit 113, the third voltage outputted by the voltage adjusting unit 140 is increased from 8V to 10V so that the current of the backlight assembly 60 is equal to the reference current. Then, the second secondary winding unit 130 increases the fourth voltage outputted from the second secondary winding unit 130 by 2V based on the second feedback signal, so that the second voltage is increased by 2V, and the voltage adjusting unit 140 decreases the third voltage to 8V for controlling the current of the backlight assembly 60 as the reference current.

The present example can be understood that the voltage adjustment unit 140 is only a transitional adjustment, the final adjustment is still performed by the second secondary winding unit 130, and the asymmetric half-bridge circuit is relatively stable due to the relatively slow feedback speed of the third feedback unit 113, so that the first secondary winding unit 120 is less affected, and the voltage adjustment unit 140 can respond to the current fluctuation of the backlight assembly 60 rapidly. In addition, the output voltage of the voltage adjusting unit 140 in this example changes only in a short period of time, and is in a constant voltage output state most of the time, so that when the voltage adjusting unit 140 is selected, a conversion module suitable for a relatively small voltage fluctuation range can be selected, and the cost of the voltage adjusting unit 140 can be reduced.

In the above three examples, as long as the feedback units can realize the corresponding feedback functions, the specific structure of each feedback unit is not limited in the present application.

As an implementation manner, fig. 10 is a schematic structural diagram of the second feedback unit in an example, as shown in fig. 10, and the second feedback unit 112 may include, on the basis of the example in fig. 9: the three-terminal voltage regulator comprises a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, a three-terminal voltage regulator N2 and a photoelectric coupler N1;

One end of the first resistor R1 is connected with the output end of the voltage adjusting unit 140, and the other end of the first resistor R1 is connected with one end of the second resistor R2; the other end of the second resistor R2 is grounded;

one end of the third resistor R3 is connected with the other end of the first resistor R1 and one end of the second resistor R2, and the other end of the third resistor R3 is connected with one end of the first capacitor C1;

the other end of the first capacitor C1 is connected with the primary side output end of the photoelectric coupler N1, and the primary side input end of the photoelectric coupler N1 receives a second reference voltage; the secondary side input end of the photoelectric coupler N1 is connected with the first controller, and the secondary side input end of the photoelectric coupler N1 is grounded;

the reference pole of the three-terminal voltage regulator N2 is connected with the other end of the third resistor R3 and one end of the first capacitor C1, the positive pole of the three-terminal voltage regulator N2 is grounded, and the negative pole of the three-terminal voltage regulator N2 is connected with the primary side output end of the photoelectric coupler N1.

Optionally, the second feedback unit 112 may further include: a fourth resistor and a fifth resistor,

one end of a fourth resistor receives the first reference voltage, and the other end of the fourth resistor is connected with the primary side input end of the photoelectric coupler N1 and one end of a fifth resistor;

the other end of the fifth resistor is connected with the positive electrode of the three-terminal voltage stabilizer N2 and the primary side output end of the photoelectric coupler N1.

In the present embodiment, the first capacitor C1 and the third resistor R3 form a low-pass filter for reducing the response speed of the feedback loop. The photoelectric coupler N1 is used for isolating the primary side and the secondary side of the transformer and avoiding mutual interference during operation.

An exemplary description will be made below in connection with an actual scenario: as shown in fig. 10, the first resistor R1 and the second resistor R2 are voltage dividing resistors, when the voltage at the output end of the voltage adjusting unit 140 increases, the voltage at the point a increases, the voltage at the point B is higher than the voltage (2.5V) at the reference electrode of the three-terminal voltage regulator N2, the current flowing from the negative electrode to the positive electrode of the three-terminal voltage regulator N2 increases, the light emitting diode of the photo coupler N1 becomes bright, and the voltage at the input end of the secondary side of the photo coupler N1 increases; conversely, when the voltage at the output end of the voltage adjusting unit 140 becomes smaller, the voltage at the point a becomes lower, the voltage at the point B is lower than the voltage (2.5V) at the reference electrode of the three-terminal voltage regulator N2, the current flowing from the negative electrode to the positive electrode of the three-terminal voltage regulator N2 decreases, the light emitting diode of the photo coupler N1 becomes dark, and the voltage at the input end of the secondary side of the photo coupler N1 decreases, so as to isolate and transmit the second feedback signal to the first controller.

The embodiment can output a reliable second feedback signal based on the sampled voltage, and the second feedback signal is isolated through the photoelectric coupler N1, so that the mutual interference of primary and secondary sides of the transformer is reduced.

As another embodiment, fig. 11 is a schematic structural diagram of a second feedback unit in an example, and the second feedback unit 112 includes, on the basis of the example of fig. 11: the three-terminal voltage regulator comprises a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, a three-terminal voltage regulator N2 and a photoelectric coupler N1;

the other end of the first capacitor C1 is connected with the primary side output end of the photoelectric coupler N1, and the primary side input end of the photoelectric coupler N1 receives a first reference voltage; the secondary side input end of the photoelectric coupler N1 is connected with the first controller, and the secondary side input end of the photoelectric coupler N1 is grounded;

the reference end of the three-terminal voltage stabilizer N2 is connected with the other end of the third resistor R3 and one end of the first capacitor C1, the positive electrode of the three-terminal voltage stabilizer N2 is grounded, and the negative electrode of the three-terminal voltage stabilizer N2 is connected with the primary side output end of the photoelectric coupler N1.

The principle is the same as the above example and will not be repeated again.

In some embodiments, the third feedback unit 113 may include a ninth resistor connected in series with the backlight assembly 60 to feedback the present current of the backlight assembly 60 by collecting voltages across the ninth resistor.

In other embodiments, the backlight assembly 60 includes at least one LED light bar, and an output terminal of the power supply unit is connected to an output terminal of each LED, and fig. 12 is a schematic structural diagram of the third feedback unit 113 in an example, and as shown in fig. 12, the third feedback unit 113 may include:

the third feedback unit 113 includes: a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8;

one end of a sixth resistor R6 is connected with the LED lamp strip, and the other end of the sixth resistor R6 is connected with the second controller;

one end of the seventh resistor R7 is connected with the output end of the second secondary winding unit 130, and the other end of the seventh resistor R7 is connected with the second controller and the other end of the sixth resistor R6;

one end of the eighth resistor R8 is connected with the second controller and the other end of the sixth resistor R6, and the other end of the eighth resistor R8 is grounded.

In the example, the third feedback unit samples the second voltage and the current of the LED, generates a third feedback signal based on superposition of the two signals, and can realize the constant current of the LED by adjusting the second voltage, thereby realizing the control of at least one path of LED light bars.

In other embodiments, the present application further provides a power supply module, including: the primary winding unit, the first secondary winding unit and the power supply unit;

the primary winding unit is used for outputting a first primary voltage and a second primary voltage in a time-sharing manner;

the first secondary winding unit is coupled to the primary winding unit, and an output end of the first secondary winding unit is connected to the main board 50 and is used for outputting a first voltage to the main board based on the first primary voltage;

the power supply unit includes: a second secondary winding unit and a voltage adjusting unit; the input end of the voltage adjusting unit is connected with the output end of the first secondary winding unit, the output end of the voltage adjusting unit is connected with the negative electrode output end of the second secondary winding unit, and the voltage adjusting unit is used for carrying out voltage transformation treatment on the first voltage and then outputting the first voltage; the second secondary winding unit is coupled with the primary winding unit, and the positive electrode output end of the second secondary winding unit is connected with the backlight component; the power supply unit is used for outputting a second voltage to the backlight assembly based on the second primary side voltage; the difference between the second voltage and the first voltage is greater than a first threshold.

The working principles of the power supply module in this embodiment and the power supply module of the display device in any of the foregoing examples are specifically referred to any of the foregoing embodiments, and are not described herein again.

Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the application pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

It is to be understood that the application is not limited to the precise arrangements and instrumentalities shown in the drawings, which have been described above, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the application is limited only by the appended claims.

Claims

1. A display device, characterized by comprising: a backlight assembly, a main board and a power supply module; the power supply module includes: the primary winding unit, the first secondary winding unit and the power supply unit;

the first secondary winding unit is coupled to the primary winding unit, and an output end of the first secondary winding unit is connected with the main board and is used for outputting a first voltage to the main board based on the first primary voltage;

the power supply unit includes: a second secondary winding unit and a voltage adjusting unit; the input end of the voltage adjusting unit is connected with the output end of the first secondary winding unit, the output end of the voltage adjusting unit is connected with the negative electrode output end of the second secondary winding unit, and the voltage adjusting unit is used for carrying out voltage transformation treatment on the first voltage and then outputting the first voltage; the second secondary winding unit is coupled to the primary winding unit, and the positive output end of the second secondary winding unit is connected with the backlight assembly; the power supply unit is used for outputting a second voltage to the backlight assembly based on the second primary side voltage; the difference between the second voltage and the first voltage is greater than a first threshold.

2. The display device of claim 1, wherein the power module further comprises: a first feedback unit, a second feedback unit, a third feedback unit and a first controller,

the input end of the first feedback unit is connected with the output end of the first secondary winding unit, the output end of the first feedback unit is connected with the first controller, and the first feedback unit is used for outputting a first feedback signal to the first controller based on the first voltage;

the second feedback unit is connected with the first controller and is used for outputting a second feedback signal to the first controller;

the first controller is connected with the primary winding unit and is used for outputting a first control signal and a second control signal to the output primary winding unit based on the first feedback signal and the second feedback signal so that the primary winding unit controls the first primary voltage and the second primary voltage based on the first control signal and the second control signal;

the voltage adjustment unit includes: a second controller is provided for controlling the operation of the first controller,

the third feedback unit is connected with the second controller and used for outputting a third feedback signal to the second controller, and the second controller controls the voltage output by the voltage adjusting unit based on the third feedback signal.

3. The display device of claim 2, wherein the display device is configured to display the plurality of images,

the input end of the second feedback unit is connected with the positive electrode output end of the second secondary winding unit and the negative electrode output end of the second secondary winding unit and is used for outputting the second feedback signal based on the pressure difference between the positive electrode output end of the second secondary winding unit and the negative electrode output end of the second secondary winding unit;

the input end of the third feedback unit is connected with the backlight assembly, and is used for sampling the current of the backlight assembly and outputting the third feedback signal based on the current of the backlight assembly.

4. The display device of claim 2, wherein the display device is configured to display the plurality of images,

the input end of the second feedback unit is connected with the backlight assembly, and the second feedback unit is used for sampling the current of the backlight assembly and outputting the second feedback signal based on the current of the light assembly;

the input end of the third feedback unit is connected with the output end of the voltage adjusting unit and is used for outputting a third feedback signal based on the output voltage of the voltage adjusting unit.

5. The display device of claim 2, wherein the display device is configured to display the plurality of images,

The input end of the second feedback unit is connected with the output end of the voltage adjusting unit and is used for outputting the second feedback signal based on the output voltage of the voltage adjusting unit;

an input end of the third feedback unit is connected with the backlight assembly, and is used for sampling the current of the backlight assembly and outputting the third feedback signal based on the current of the backlight assembly;

the feedback speed of the third feedback unit is faster than that of the second feedback unit.

6. The display device according to claim 5, wherein the second feedback unit includes: the three-terminal voltage regulator comprises a first resistor, a second resistor, a third resistor, a first capacitor, a three-terminal voltage regulator and a photoelectric coupler;

one end of the first resistor is connected with the output end of the voltage adjusting unit, and the other end of the first resistor is connected with one end of the second resistor; the other end of the second resistor is grounded;

one end of the third resistor is connected with the other end of the first resistor and one end of the second resistor, and the other end of the third resistor is connected with one end of the first capacitor;

the other end of the first capacitor is connected with the primary side output end of the photoelectric coupler, and the primary side input end of the photoelectric coupler receives a second reference voltage; the secondary side input end of the photoelectric coupler is connected with the first controller, and the secondary side input end of the photoelectric coupler is grounded;

The reference electrode of the three-terminal voltage stabilizer is connected with the other end of the third resistor and one end of the first capacitor, the positive electrode of the three-terminal voltage stabilizer is grounded, and the negative electrode of the three-terminal voltage stabilizer is connected with the primary side output end of the photoelectric coupler.

7. The display device according to claim 6, wherein the second feedback unit further comprises: a fourth resistor and a fifth resistor,

one end of the fourth resistor receives a first reference voltage, and the other end of the fourth resistor is connected with the primary side input end of the photoelectric coupler and one end of the fifth resistor;

the other end of the fifth resistor is connected with the positive electrode of the three-terminal voltage stabilizer and the primary side output end of the photoelectric coupler.

8. The display device of any one of claims 1-7, wherein the power module further comprises: a second capacitor is provided between the first capacitor and the second capacitor,

one end of the second capacitor is connected with the output end of the voltage adjusting unit, and the other end of one end of the second capacitor is grounded.

9. The display device according to any one of claims 1 to 7, wherein the voltage adjustment circuit is a buck conversion circuit or a boost conversion circuit.

10. A power module, comprising: the primary winding unit, the first secondary winding unit and the power supply unit;

the power supply unit includes: a second secondary winding unit and a voltage adjusting unit; the input end of the voltage adjusting unit is connected with the output end of the first secondary winding unit, the output end of the voltage adjusting unit is connected with the negative electrode output end of the second secondary winding unit, and the voltage adjusting unit is used for carrying out voltage transformation treatment on the first voltage and then outputting the first voltage; the second secondary winding unit is coupled to the primary winding unit, and the positive electrode output end of the second secondary winding unit is connected with the backlight assembly; the power supply unit is used for outputting a second voltage to the backlight assembly based on the second primary side voltage; the difference between the second voltage and the first voltage is greater than a first threshold.