CN115250068A - Multi-path feedback method, circuit and display device - Google Patents

Abstract

The application provides a multichannel feedback method, a multichannel feedback circuit and a display device, wherein the multichannel feedback circuit can receive independent feedback signals respectively, and each feedback signal is processed according to different duty ratios, so that the independent feedback circuits are combined together, controllers are arranged on each feedback circuit respectively, and the circuit complexity is reduced.

Description

Multi-path feedback method, circuit and display device

Technical Field

The present disclosure relates to the field of electronic technologies, and in particular, to a multi-channel feedback method, a multi-channel feedback circuit, and a display device.

Background

With the development of electronic technology, the integration level of electronic equipment including display devices such as televisions is higher and higher, and higher requirements are put on power modules of the display devices. At present, after a power module arranged in most display devices receives commercial power alternating current through a plug, a special power supply circuit is adopted to convert the alternating current into direct current, transform the alternating current and the like, and then the power supply module supplies power to loads in the display devices.

In the related art, a power supply circuit for implementing a step power supply includes at least the following modules: the Power Factor Correction (PFC) circuit comprises a rectifier bridge, a PFC (Power Factor Correction) module and a flyback module, and finally, different windings of the flyback module respectively output voltage signals to different loads. When the load is a mainboard of the display device, a flyback module in the power supply module adjusts the voltage output by the secondary winding to the mainboard in a voltage flyback mode to realize feedback; when the load is an LED light bar, a voltage adjusting circuit is further arranged in the power supply module, and the voltage output to the LED light bar is adjusted through a constant-current controlled voltage adjusting circuit in the type of a Boost circuit/Buck voltage reducing circuit.

By adopting the related technology, the feedback signals of the loads are processed by the power supply module independently, so that the complexity of a feedback circuit required for processing the feedback signals in the power supply module is higher.

Disclosure of Invention

The application provides a multi-path feedback method, a multi-path feedback circuit and a display device, which are used for reducing the complexity of a feedback circuit in a power module.

The application provides a multi-path feedback circuit which is respectively connected with a plurality of loads and a power supply circuit for supplying power to the plurality of loads; the method comprises the following steps: the multi-path feedback circuit is configured to receive feedback signals corresponding to a plurality of loads in a plurality of different time periods in a preset period respectively; a display panel configured to display an image;

a logic board TCON configured to control the display panel to display an image;

a backlight assembly configured to light the display panel;

a controller configured to send an image to be displayed to the TCON, so that the TCON controls the display panel to display the image to be displayed; and sending a control signal to the backlight assembly according to an image to be displayed, wherein the control signal is used for controlling the backlight assembly to emit light;

a power supply circuit configured to supply power to a load of the display apparatus;

and the multi-path feedback circuit is configured to receive feedback signals corresponding to the plurality of loads respectively in a plurality of different time periods in a preset period, and adjust the voltage output by the power supply circuit to the load corresponding to the feedback signal according to the feedback signals.

In an embodiment of the first aspect of the present application,

the multi-path feedback circuit comprises: the switching tubes are arranged between the output end of the power supply circuit and the loads; the multi-path feedback circuit is specifically configured to respectively turn on a switch tube corresponding to one load in a plurality of different time periods in a preset period, and receive a feedback signal of the one load.

In an embodiment of the first aspect of the present application,

the multi-path feedback controller is configured to adjust the voltage output by the power supply circuit to the first load by adjusting the ratio of the conduction time of the first switching tube connected with the first load in a preset period when receiving a first feedback signal corresponding to the first load from the plurality of loads.

In an embodiment of the first aspect of the present application,

the multi-path feedback circuit further comprises: a multi-path feedback controller; the multi-path feedback control device is configured to control the on and off of the plurality of switching tubes.

In an embodiment of the first aspect of the present application,

the power supply circuit includes: a primary winding configured to receive an input voltage; a plurality of secondary windings, each having an anode for connection to a load and configured to output a voltage to the connected load; wherein,

the secondary windings share the negative electrode and are grounded; alternatively, the negative electrode of the second secondary winding among the plurality of secondary windings is connected to the positive electrode of the first secondary winding, while the negative electrode of the first secondary winding is grounded.

In an embodiment of the first aspect of the present application,

the power supply circuit includes: the flyback control circuit is used for adjusting the voltage output by the power supply circuit; the multi-path feedback circuit is also configured to send indication information to the flyback control circuit according to the feedback signal, so that the flyback controller adjusts the voltage output by the power supply circuit to the load according to the indication information.

In an embodiment of the first aspect of the present application,

the flyback control circuit includes: the flyback controller and the fourth switching tube; the multi-path feedback controller is connected with the flyback controller, the flyback controller is connected with the control end of the flyback switching tube, and the flyback switching tube is arranged between the primary winding and the grounding point; the flyback controller is configured to control the duty ratio of the conduction time of the flyback switching tube according to the indication information, and adjust the voltage output by the plurality of secondary windings.

In an embodiment of the first aspect of the present application,

the feedback signal is used to indicate the operating voltage or operating current of the load.

A second aspect of the present application provides a display device comprising: a power supply module comprising a multi-feedback circuit as claimed in any one of the first aspects of the present application.

A third aspect of the present application provides a multi-feedback method, which can be implemented by the multi-feedback circuit provided in the first aspect of the present application, and includes: respectively receiving feedback signals corresponding to a plurality of loads in a plurality of different time periods in a preset period; and according to the feedback signal, adjusting the voltage output by the power supply circuit to the load corresponding to the feedback signal.

In summary, according to the multi-path feedback method, the multi-path feedback circuit and the display device provided by the application, the multi-path feedback circuit can receive respective independent feedback signals, and each feedback signal is processed according to different duty ratios, so that the independent feedback circuits are combined together, the situation that each feedback circuit is provided with a controller is reduced, the circuit complexity is reduced, and the standardized design of the PCB wiring and power supply schemes is facilitated. And because the driving inductance in the Boost circuit/Buck voltage reduction circuit is reduced, the influence on other devices by the inductance is avoided, the design and manufacturing cost of a display device, a power supply module and related circuits is reduced on the basis of further reducing the complexity of the circuit, and the power supply efficiency is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments or related technologies of the present application, the drawings needed to be used in the description of the embodiments or related technologies are briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of a display device with an independent power board;

FIG. 2 is a schematic diagram illustrating a connection relationship between a power board and a load of the display device;

FIG. 3A is a schematic diagram of a power architecture of a television;

FIG. 3B is a schematic diagram of another television power architecture;

FIG. 4 is a schematic diagram of an embodiment of a power supply circuit on a power board of a display device;

FIG. 5 is a schematic diagram of another embodiment of a power supply circuit on a power board of a display device;

fig. 6 is a schematic structural diagram of an embodiment of a display device provided in the present application;

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

FIG. 8 is a timing diagram illustrating the control of the multi-path feedback controller provided herein;

FIG. 9 is a schematic diagram of the voltage across the fourth switch tube provided in the present application;

fig. 10 is a schematic structural diagram of another embodiment of a display device provided in the present application;

FIG. 11 is a schematic structural diagram of another embodiment of a display device provided in the present application;

fig. 12 is a schematic structural diagram of another embodiment of a display device provided by the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims of the present application and in the drawings described above, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The following first describes a scenario in which the present application is applied and problems that may occur with reference to the drawings. As the demand for obtaining information is continuously increasing, various types of display devices, such as computers, televisions, projectors, etc., are being developed. The power supply circuit is one of the most important circuit structures in the display device, and the power supply circuit can provide electric energy for the display device, so that the display device can normally operate. Some display devices are provided with independent power panels, and some display devices combine the power panels and the main board into a whole.

Taking a display device provided with an independent power board as an example, a 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 board, and as shown in fig. 1, the display device includes a display panel 1, a backlight assembly 2, a main board 3, a power board 4, a rear case 5 and a base 6. The display panel 1 is used for presenting pictures to a user; the backlight assembly 2 is located below the display panel 1, usually some optical assemblies, and is used for supplying sufficient light sources with uniform brightness and distribution, so that the display panel 1 can normally display images, the backlight assembly 2 further includes a back plate 20, the main board 3 and the power board 4 are arranged on the back plate 20, usually some convex hull structures are formed by punching on the back plate 20, and the main board 3 and the power board 4 are fixed on the convex hulls through screws or hooks; the rear shell 5 is covered on the panel 1 to hide the parts of the display device such as the backlight assembly 2, the main board 3 and the power panel 4, and the like, thereby achieving the effect of beautiful appearance; and a base 6 for supporting the display device.

In some embodiments, fig. 2 is a schematic diagram of a connection relationship between a power board and a load of a display device, as shown in fig. 2, the power board 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 commercial power, the output terminal 42 is connected to a load in the display device, 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, and the third output terminal 423 is connected to a main board. The power board 4 needs to convert ac power into dc power required by the load, and the dc power generally has different voltage specifications, such as 18V for sound, 12V for panel, etc.

In some embodiments, a power architecture of a display device is described by taking a television as an example, and fig. 3A is a schematic diagram of a power architecture of a television, as shown in fig. 3A, a power panel may specifically include: the Power plug 11, the rectifying and filtering module 12, the Power Factor Correction (PFC) module 131, and the resonant converter (LLC) module 132, wherein the LLC module 132 may include a synchronous rectifying circuit (not shown in fig. 3A), the PFC module 131 is connected to the LLC module 132, and the LLC module 132 is connected to a plurality of loads, which are denoted as load 1 and load 2 … ….

The rectifying and filtering module 12 may be a rectifying bridge, and is configured to rectify the commercial power ac input by the power plug 11 and input a full-wave signal to the PFC module 131. An Electromagnetic Interference (EMI) filter (not shown in fig. 3A) may be connected before the ac power is input into the PFC module to perform high frequency filtering on the input ac power.

The PFC module 131 may include a PFC inductor, a switching power device, and a PFC control chip, and mainly performs power factor correction on an input ac power source to output a stable dc bus voltage (e.g., 380V) to the LLC module 132. The PFC module 131 can effectively increase the power factor of the power supply, and ensure the same phase of the voltage and the current. Alternatively, in some embodiments, the PFC module 131 may not be provided in the power architecture shown in fig. 3A.

The LLC module 132 may employ a double-MOS transistor LLC resonant conversion circuit, and typically a synchronous rectification circuit is disposed in the LLC module, and the synchronous rectification circuit may mainly include a transformer, a controller, two MOS transistors, and a diode. In addition, the LLC module may further include a Pulse Frequency Modulation (PFM) circuit, a capacitor, an inductor, and other components. The LLC module may specifically step down or step up the dc bus voltage input by the PFC module, and output a constant voltage to the load. In general, LLC modules are capable of outputting a variety of different voltages to meet the demands of different loads.

Alternatively, in another embodiment, fig. 3B is a schematic diagram of another television power supply architecture, in fig. 3B, the LLC module 132 shown in fig. 3A may be replaced by the flyback voltage conversion module 14, and the flyback voltage conversion module 14 steps down or up the voltage and outputs a constant voltage to the load.

In some embodiments, also taking the display device as a television as an example, fig. 4 is a schematic structural diagram of an embodiment of a power supply circuit on a power board of the display device, wherein the display device in fig. 3B is taken as an example to explain that, after the commercial power alternating current (100V-240v, 50-60 Hz) obtained by the power supply circuit from the power plug 11 passes through the rectifying and filtering module 12 and the flyback module 14 in fig. 3B in sequence, the power is supplied to the main board 15, the LED light bar 16 and other loads of the display device, which are not shown in fig. 4. It can be understood that if fig. 4 is applied in fig. 3A, the ac mains power may sequentially pass through the filtering and rectifying module 12 (rectifying bridge), the PFC module 131 and the LLC module 132 in fig. 3A to supply power to the load.

In some embodiments, the first secondary winding Ns1 in the flyback module 14 shown in fig. 4 may provide a voltage Vcv1 of 12V to the main board 15; the second secondary winding Ns2 outputs a voltage Vcv2, and then the voltage Vcv2 is boosted by the voltage adjusting circuit 22 of the Boost structure to obtain a voltage Vled for supplying power to the LED light bar 16, so that the LED light bar lights the display screen of the television. The voltage Vcv1 and the voltage Vcv2 output to the load by the LLC module 132 or the flyback module 14 may be determined by the turn ratio of the secondary windings Ns2 and Ns1, and expressed by the formula Vcv2= Vcv1 × Ns2/Ns1.

It should be noted that, the voltage of 12V output to the main board 15 shown in fig. 4 is only an example, and in practical applications, voltages with other voltage values may be output, or more secondary windings may be further disposed in the LLC module 132 or the flyback module 14, and each secondary winding may be used to output one voltage.

In some embodiments, the flyback module 14 may specifically adjust the voltage Vcv1 output by the secondary winding Ns1 and the voltage Vcv2 output by the secondary winding Ns2 in a flyback control manner, so as to keep the voltages stable. For example, the Flyback module 14 in fig. 4 specifically includes a Flyback controller (Flyback IC), and a MOS transistor Q1 connected to the primary winding Np of the Flyback module 14. The voltage Vcv1 output by the secondary winding Ns1 passes through the reflected voltage Vro of the flyback module 14, and is expressed by the formula Vro = Np × Vcv1/Ns1= Np × Vcv2/Ns2, which is the same as the voltage Vcv2 output by the secondary winding Ns2 that passes through the reflected voltage Vro of the flyback module 14. When the flyback controller receives a voltage feedback signal FB1 at the output end of the Vcv1 through an isolation device such as an optical coupler, the duty ratio of the MOS transistor Q1 can be adjusted according to the feedback signal, so as to adjust the voltage Vcv1 output by the secondary winding Ns1 and the voltage Vcv2 output by the secondary winding Ns2.

In some embodiments, since the LED light bar needs to operate with a certain voltage drop to reach its rated current, for example, the voltage range required by the LED under 120mA condition is 51.3V-58.5V, and the total current is 1.92A. In order to adjust the current output from the flyback module 14 to the LED light bar 16, the Boost controller (Boost IC), the MOS transistor Q2, the inductor L, and the diode VD3 are specifically included in the voltage adjusting circuit 22 of the Boost structure provided in the display device shown in fig. 4, and in the voltage adjusting circuit of the Boost structure, the relationship between the input voltage Vcv2 and the voltage VL of the inductor L, and the relationship between the voltage VVD3 of the diode VD3 and the output voltage Vled can be represented by the following relationship: vled = Vcv2+ VL-VVD3, the voltage value of VVD3 is small and can be ignored, the output voltage Vled is larger than the input voltage Vcv2, and the boosting effect is realized. Specifically, the voltage adjusting circuit 22 realizes boosting through the duty ratio of the MOS transistor Q2, and in the on-state of the switching transistor Q2, the diode VD3 is turned off, and the input voltage Vcv2 directly returns after passing through the inductor VL, so that the inductor VL accumulates electric energy; at the cut-off stage of the switching tube Q2, the diode VD3 is turned on, and since the current of the inductor cannot suddenly change instantaneously, the input voltage Vcv2 is connected in series with the voltage provided by the inductor VL, and then the output voltage Vled is provided together to realize boosting. Meanwhile, the Boost controller is further configured to receive a current feedback signal FB2 of the working current of the LED light bar 16, and adjust the duty ratio of the MOS transistor Q2 according to the feedback signal to adjust the voltage value of Vled output by the Boost circuit, thereby adjusting the current flowing through the LED light bar 16 and maintaining the stability of the working current of the LED light bar 16.

In some embodiments, the Boost circuit with the Boost structure shown in fig. 4 may also be implemented by replacing a Buck circuit with a Buck structure, and the Buck circuit with the Buck structure may be configured to step down the voltage Vcv2 output by the secondary winding Ns2 to obtain Vled, and then supply power to the LED light bar 16. For example, fig. 5 is a schematic structural diagram of another embodiment of a power supply circuit on a power board of a display device, and the voltage adjustment circuit 22 shown in fig. 5 includes a Buck controller (Buck IC), a diode VD3, an inductor L and a MOS transistor Q2 based on the circuit shown in fig. 4. In the buck-structured voltage regulator circuit, the relationship between the input voltage Vcv2, the voltage VL of the inductor L, the voltage VVD3 of the diode VD3, and the output voltage Vled can be expressed by the following relationship: vcv2= Vled + VL, and the output voltage Vled < the input voltage Vcv2, thereby achieving a boosting effect. Specifically, the voltage adjusting circuit 22 realizes boosting through the duty ratio of the MOS transistor Q2, and in the on-state of the switching transistor Q2, the diode VD3 is turned off, and the input voltage Vcv2 directly returns after passing through the inductor VL, so that the inductor VL accumulates the electric energy of the difference between Vled and Vcv 2; in the cut-off stage of the switching tube Q2, the diode VD3 is turned on, and since the current of the inductor cannot suddenly change instantaneously, the output voltage of the inductor VL is used as Vled to supply power to the load. Meanwhile, after receiving a current feedback signal FB2 of the working current of the LED lamp bar 16, the Buck controller can adjust the duty ratio of the MOS tube Q2 according to the feedback signal to adjust the voltage value of the Vled output by the Buck Buck circuit.

In the circuits shown in fig. 4 and 5, on the basis that the power supply circuit provides different voltages to different loads through different secondary windings, the flyback module may adjust the voltage output by the secondary winding through one side of the primary winding in a voltage flyback manner, and the voltage adjustment circuit on one side of the secondary winding may adjust the voltage actually output by the secondary winding to the LED light bar through a constant current control manner. In addition, because the driving inductor is introduced into the voltage adjusting circuit of the Boost/Buck structure, normal operation of other elements in the feedback circuit and the power supply circuit can be affected in the PCB implementation of the circuit, so that the inductor needs to be designed and avoided in the PCB layout wiring process, and the circuit complexity, the design cost and the manufacturing cost are further improved.

Therefore, the embodiment of the application further provides a multi-path feedback method, a multi-path feedback circuit and a display device, the multi-path feedback circuit can receive independent feedback signals respectively, and each feedback signal is processed according to different duty ratios, so that the independent feedback circuits are combined together to be realized, the number of controllers respectively arranged on each feedback circuit is reduced, the circuit complexity is further reduced, and the standardized design of PCB wiring and a power supply scheme is facilitated. And because the driving inductance in the Boost circuit/Buck voltage reduction circuit is reduced, the influence on other devices by the inductance is avoided, the design and manufacturing cost of a display device, a power supply module and related circuits is reduced on the basis of further reducing the complexity of the circuit, and the power supply efficiency is improved.

The technical solution of the present application will be described in detail below with specific examples. These several specific embodiments may be combined with each other below, and details of the same or similar concepts or processes may not be repeated in some embodiments.

Fig. 6 is a schematic structural diagram of an embodiment of the display device provided in the present application, and the display device shown in fig. 6 includes at least one load, which is exemplified by a load 1 and a load 2 … …. Then the power supply module of the power supply display device sequentially comprises: the power supply module can be used for respectively supplying power to at least one load and providing working voltage and working current corresponding to the load. Meanwhile, the power supply module in the display device provided by this embodiment further includes: and the multi-path feedback circuit 17, wherein the multi-path feedback circuit 17 is configured to receive feedback signals corresponding to all of the plurality of loads in a plurality of different time periods within a preset period, and separately adjust the voltage output to the load by the flyback module according to the feedback signal of each load. Compared with the embodiments shown in fig. 3-5, the feedback circuits of different loads in the display device are designed comprehensively, and one multi-path feedback circuit 17 can be used for receiving the feedback signals of different loads in a time-sharing manner and adjusting the output voltage according to the received feedback signals. Thereby reducing a feedback controller required for each load in feedback and reducing the circuit complexity of a power supply module of the display device.

In some embodiments, fig. 7 is a schematic structural diagram of another embodiment of the display device provided in the present application, and as shown in fig. 7, a specific circuit implementation of the display device shown in fig. 6 is shown, where, taking a plurality of loads of the display device including two loads, namely a main board 15 and a backlight assembly 16 as an example, the main board 15 may specifically include a logic board TCON configured to control a display panel of the display device to display an image, and a controller (SoC, etc.) configured to send the image to be displayed to the TCON and send a control signal to the backlight assembly 16 according to the image to be displayed, so that the backlight assembly 16 and the display panel jointly present the image to be displayed. The backlight assembly 16 may be an LED assembly 16 configured to illuminate the backlight assembly, and the power supply circuit is configured to supply power to the main board 15 and the LED assembly 16, respectively. The power supply to the motherboard 15 is equivalent to the power supply to the devices on the motherboard 15, the voltage output to the motherboard 15 may be 12V, 18V, and the like, and the motherboard 15 transmits the voltage to the corresponding devices on the motherboard 15.

Meanwhile, the multi-path feedback circuit 17 may be configured to receive a first feedback signal indicating the working voltage of the main board 15, and adjust the voltage output by the power supply circuit to the main board 15 according to the first feedback signal; and, the multi-path feedback circuit 17 may be further configured to receive a second feedback signal indicating the operating current of the LED module 16, and adjust the voltage output by the power supply circuit to the LED module 16 according to the second feedback signal. The operation of the multi-feedback circuit 17 will be described with reference to fig. 7, taking the load comprising the main board 15 and the LED module 16 as an example.

In some embodiments, the present application provides a multi-feedback circuit of a display device, including: and each switching tube is arranged between the output end of the power supply circuit and one corresponding load. The multi-path feedback circuit can be used for turning on a switch tube corresponding to one load to receive a feedback signal corresponding to the one load in different time periods in a preset period. For example, in an example as shown in fig. 7, a power supply circuit in a power supply module of a display device includes: power plug 11, rectification filter module 12 and flyback module 14, wherein, flyback module 14 specifically includes: a primary winding Np, a first secondary winding Ns1, and a second secondary winding Ns2. The primary winding Np is configured to receive an input voltage of the rectifying and filtering module 12, and the first secondary winding Ns1 may be configured to convert the input voltage received by the primary winding Np into a first voltage Vcv1 and output the first voltage Vcv1, for example, the first voltage may be 12V voltage output to the motherboard 15, and then a positive electrode of the first secondary winding Ns1 is connected to the motherboard 15, and a negative electrode of the first secondary winding Ns1 is grounded. The second secondary winding Ns2 may be configured to convert an input voltage of the primary winding Np into a second voltage Vled and output the second voltage Vled, a positive electrode of the second secondary winding Ns2 is connected to a positive electrode of the LED assembly 16, a negative electrode of the second secondary winding Ns2 and the first secondary winding Ns1 share a negative electrode, and a negative electrode of the LED assembly 16 is connected to the multi-path feedback controller 171 and is grounded through a ground terminal of the multi-path feedback controller 171.

In some embodiments, the multi-feedback circuit as shown in fig. 7 comprises: a multi-feedback controller 171 (Driver IC) for receiving feedback signals corresponding to the motherboard 15 and the LED module 16, wherein the multiple switching tubes in the multi-feedback circuit include: a first switch tube VD1 and a second switch tube Q2. The Multi-channel feedback controller 171 may be a processor, an integrated circuit, or a physical device and apparatus with related processing capability, such as a Multi-output/LED controller, and the input interfaces thereof are respectively used for receiving a first feedback signal corresponding to the motherboard 15 and a second feedback signal corresponding to the LED module 16. The first switch tube VD1 is arranged between the anode of the second secondary winding Ns2 and the anode of the LED assembly 16, the anode of the first switch tube VD1 is connected with the anode of the second secondary winding Ns2, the cathode of the first switch tube VD1 is connected with the anode of the LED assembly 16, and the control end of the first switch tube VD1 is connected with the multi-path feedback controller 171. Two ends of the second switching tube Q2 are connected between the positive electrode of the first secondary winding Ns1 and the main board 15, and a control end of the second switching tube Q2 is connected with the multi-path feedback controller 171. The multi-path feedback circuit further comprises: the third switching tube Q3 is disposed between the negative electrode shared by the first secondary winding Ns1 and the second secondary winding Ns2 and the ground point, and the control terminal of the third switching tube Q3 is connected to the multi-path feedback controller 171.

In some embodiments, the multi-path feedback controller 171 may specifically receive the multi-path feedback signal and adjust the multi-path output voltage by controlling the first switching tube VD1 and the second switching tube Q2 to conduct in a time-sharing manner. For example, fig. 8 is a control timing diagram of the multi-path feedback controller provided by the present application, where T1-T2 is taken as a preset period, in the preset period, in a period of 50% before T1-T1, the multi-path feedback controller 171 controls two ends of the second switching tube Q2 and the third switching tube Q3 to be respectively turned on, and controls the first switching tube VD1 to be turned off, then the multi-path feedback controller 171 may receive a first feedback signal FB1 for indicating the operating voltage of the motherboard, and in a period of 50% after T1-T2 in the preset period, the multi-path feedback controller 171 controls two ends of the first switching tube VD1 and the third switching tube Q3 to be respectively turned on, and controls the second switching tube Q2 to be turned off, and then the multi-path controller 171 may receive a second feedback signal FB2 for indicating the supply current of the LED module. Subsequently, the multi-path feedback controller 171 will repeatedly execute the above control steps in consecutive preset periods, so as to receive the feedback signals of different paths by means of time-sharing conduction of the switching tubes.

In some embodiments, based on the fact that the duty ratio of the multi-path feedback controller 171 can be varied suddenly during time-sharing control, the multi-path feedback controller 171 can adjust the duty ratio of the received feedback signal according to the first feedback signal FB1 or the second feedback signal FB2, that is, the ratio of the first part time to the second part time in the preset period, thereby adjusting the energy of the voltage output to different loads. For example, in the example shown in fig. 8, after the time T1 and before the time T2, assuming that the multi-path feedback controller 171 determines that the voltage output to the main board needs to be increased and adjusted according to the received first feedback signal FB1, at the time T2-T2 in the preset period after the time T2, the multi-path feedback controller 171 increases the ratio of the time for controlling the two ends of the second switching tube Q2 and the third switching tube Q3 to be respectively turned on, that is, increases the duty ratio Ns, so that the first secondary winding 1 outputs more energy, and increases the voltage output to the main board 15. Assuming that the multi-path feedback controller 171 determines that the current output to the LED light bar needs to be increased according to the received second feedback signal FB2, at time T2-T3 within a preset period after the time T2, the multi-path feedback controller 171 controls the time duty ratio of respective conduction of the two ends of the first switching tube VD1 and the third switching tube Q3 to be decreased, that is, the duty ratio is decreased, so that the second secondary winding Ns2 outputs less energy, and the current output to the LED light bar is decreased.

In some embodiments, the multi-feedback circuit shown in fig. 7 further comprises: the Flyback controller Flyback and the fourth switching tube Q1 are arranged on the primary side of the Flyback module, and are used for controlling the Flyback controller 171 to realize Flyback adjustment of the output voltage of the secondary winding under the condition that the multi-path feedback controller 171 cannot realize a feedback target by controlling the first switching tube VD1 and the second switching tube Q2; alternatively, when the multi-path feedback controller 171 can achieve the control target by controlling the first switching tube VD1 and the second switching tube Q2, feedback adjustment is performed together by adding the fourth switching tube Q1, so as to improve the response speed. One end of the flyback controller is connected to the multi-path feedback controller 171 through an isolation device such as an optocoupler, the other end of the flyback controller is connected to the control end of the fourth switching tube Q1, and two ends of the fourth switching tube Q1 are connected to the primary winding Ns and the ground respectively. The multi-path feedback controller 171 may send the indication information to the flyback controller according to the first feedback signal or the second feedback signal, so that after the flyback controller receives the indication information, the duty ratio of the fourth switching tube Q1 is controlled according to the indication information, and the adjustment of the output voltages of the first secondary winding Ns1 and the second secondary winding Ns2 is implemented.

In some embodiments, the first switching tube VD1 is a diode, and the second switching tube Q2 and the third switching tube Q3 are MOS tubes, and the first switching tube VD1 is implemented by a diode, which can reduce the cost of using the MOS tubes to some extent, and further reduce the overall cost of the display device. Then, for the flyback controller, different reflected voltages may be designed at multiple outputs of the flyback module, so that the voltage Vled output by the second secondary winding Vs2 is greater than the reflected voltage of the first voltage Vcv1 output by the first secondary winding Vs1, which is expressed by the formula Np × Vled/Ns2> Np × Vcv1/Ns1. For example, fig. 9 is a schematic diagram of the voltage across the fourth switching tube provided by the present application, where, taking the preset period T1-T2 shown in fig. 9 as an example, at the time of the first T1-T1 within T1-T2, the voltage across the fourth switching tube is the sum of the reflected voltage Vro1 of the first voltage Vcv1 and the input voltage Vdc, and at the time of T1-T2, the voltage across the fourth switching tube is the sum of the reflected voltage Vro2 of the second voltage Vled and the input voltage Vdc.

In some embodiments, since the multi-path feedback controller can switch the duty ratio, the first voltage Vcv1 of the first secondary winding output Ns1 can operate in a Continuous Conduction Mode (CCM), and the duty ratio signal is Continuous; the second voltage Vled output by the second secondary winding Ns2 may work in a Discontinuous Conduction Mode (DCM) Mode, and the duty ratio signals are Discontinuous. Or, in other embodiments, on the premise that the reflected voltage follows and the high-voltage output is greater than the reflected voltage of the low-voltage output, the second secondary winding Vs2 outputting a higher voltage operates in the DCM mode, and at the same time, the first secondary winding Vs1 may operate in the CCM or DCM mode, where when the load connected to the first secondary winding Vs1 is greater than a certain power, the first secondary winding may operate in the DCM mode and the load is less than the certain power, the first secondary winding may operate in the CCM mode.

In some embodiments, fig. 10 is a schematic structural diagram of another embodiment of the display device provided by the present application, and based on the embodiment shown in fig. 7, in the display device shown in fig. 10, a secondary winding Ns3 may be additionally provided in the flyback module, and is used for converting the input voltage into a third voltage Vcv2 and outputting the third voltage Vcv2, and the secondary winding Ns3 is further connected to the MOS transistor Q4, and the control terminal of the MOS transistor Q4 is connected to the multi-path feedback controller 171, so that the multi-path feedback controller 171 can receive three paths of feedback signals in a time-sharing manner by controlling VD1, Q2, and Q4. It can be understood that the flyback module may continue to add the secondary winding and be connected to the MOS transistor for time-sharing control, and the specific implementation manner and principle thereof are the same and will not be described again.

In some embodiments, fig. 11 is a schematic structural diagram of another embodiment of the display device provided by the present application, and in the display device shown in fig. 11, on the basis of the embodiment shown in fig. 10, a MOS transistor of a third switching transistor Q3 may be replaced by a diode VD2, so as to implement the same function as that of the switching transistor Q3, so as to further reduce the cost brought by the MOS transistor.

In some embodiments, in the power supply circuit in each of the foregoing embodiments of the present application, the first secondary winding and the second secondary winding are taken as an example, and both of them share a ground terminal. For example, fig. 12 is a schematic structural diagram of another embodiment of the display device provided in the present application, in the embodiment shown in fig. 2, a negative electrode of the second secondary winding Ns2 is connected to a positive electrode of the first secondary winding Ns1, and a negative electrode of the first secondary winding Ns1 is grounded, so that the first secondary winding Ns1 and the second secondary winding Ns2 are commonly used to superpose and output the second voltage Vled; meanwhile, the first secondary winding Ns1 may still output the first voltage Vcv1 alone.

The embodiment of the present application further provides a multi-path feedback method, which can be applied to the multi-path feedback circuit provided by the present application and executed by the multi-path feedback controller, where the method includes:

s101: and respectively receiving feedback signals corresponding to the loads in a plurality of different time periods in a preset period.

In the method provided in this embodiment, the multi-path feedback controller may receive different feedback signals within a preset period, for example, taking the timing chart shown in fig. 8 as an example, the feedback signal of one load is received during a time period T1-T1 and the feedback signal of another load is received during a time period T1-T2 between the preset periods T1-T2.

S102: and adjusting the voltage output by the load corresponding to the two feedback signals of the power supply circuit according to the feedback signals.

Subsequently, in S102, after receiving the feedback signal, the multi-path controller may adjust the voltage output by the power supply circuit according to the received feedback signal. For example, after a feedback signal corresponding to a load in a time period of T1-T1 is received, the duty ratio of the switching tube is adjusted to adjust the voltage output to the load in a time period corresponding to the load in a next preset period of T2-T2; for another example, after the feedback signal corresponding to the load in the time period T1-T2 is received, the duty ratio of the switching tube is adjusted in the time period corresponding to the load in T2-T3 in a preset period, so that the voltage output to the load is adjusted.

For the specific implementation manner and principle of the multi-path control method in this embodiment, reference may be made to the specific steps performed by the multi-path controller in the multi-path control circuit provided in this application, and details are not repeated.

Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.

Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

Claims (10)

1. A multi-path feedback circuit is characterized in that,

the multi-path feedback circuit is respectively connected with a plurality of loads and a power supply circuit for supplying power to the plurality of loads;

the multi-path feedback circuit is configured to receive feedback signals corresponding to the plurality of loads in a plurality of different time periods in a preset period respectively; and adjusting the voltage output by the power supply circuit to the load corresponding to the feedback signal according to the feedback signal.

2. The multi-feedback circuit of claim 1, wherein the multi-feedback circuit comprises:

the switching tubes correspond to the loads and are arranged between the output end of the power supply circuit and the loads;

the multi-path feedback circuit is specifically configured to respectively turn on a switch tube corresponding to one load in a plurality of different time periods in the preset period, and receive a feedback signal of the one load.

3. The multi-feedback circuit of claim 2, wherein the multi-feedback controller is configured to,

when a first feedback signal corresponding to a first load in the plurality of loads is received, the voltage output to the first load by the power supply circuit is adjusted by adjusting the ratio of the conduction time of a first switching tube connected with the first load in a preset period.

4. The multi-feedback circuit of claim 3, further comprising:

a multi-path feedback controller; the multi-feedback control device is configured to control the on and off of the plurality of switching tubes.

5. The multi-feedback circuit of any of claims 1-4, wherein the power supply circuit comprises:

a primary winding configured to receive an input voltage;

a plurality of secondary windings, each having an anode for connection to a load and configured to output a voltage to the connected load; wherein the plurality of secondary windings share a negative ground; or the negative electrode of a second secondary winding in the plurality of secondary windings is connected to the positive electrode of a first secondary winding, and the negative electrode of the first secondary winding is grounded.

6. The multi-feedback circuit of claim 5, wherein the power supply circuit comprises:

the flyback control circuit is used for adjusting the voltage output by the power supply circuit;

the multi-path feedback circuit is also configured to send indication information to a flyback control circuit according to the feedback signal, so that the flyback controller adjusts the voltage output by the power supply circuit to the load according to the indication information.

7. The multi-feedback circuit of claim 6, wherein the flyback control circuit comprises:

the flyback controller and the fourth switching tube; the multi-path feedback controller is connected with the flyback controller, the flyback controller is connected with the control end of the flyback switching tube, and the flyback switching tube is arranged between the primary winding and the grounding point;

the flyback controller is configured to control the duty ratio of the conduction time of the flyback switching tube according to the indication information, and adjust the voltage output by the plurality of secondary windings.

8. The multi-feedback circuit of claim 1,

the feedback signal is used to indicate an operating voltage or an operating current of the load.

9. A display device, comprising:

a power supply module comprising the multi-way feedback circuit of any one of claims 1-8.

10. A multi-feedback method, comprising:

respectively receiving feedback signals corresponding to the loads in a plurality of different time periods in a preset period;

and adjusting the voltage output by the power supply circuit to the load corresponding to the feedback signal according to the feedback signal.

Images