Backlight module, driving method therefor, and display device comprising same

Abstract

A backlight module, a driving method therefor, and a display device comprising same. The backlight module comprises: a backlight source and a backlight circuit board (20). The backlight source comprises a lamp panel (10), wherein the lamp panel (10) comprises at least one lamp area (11). The backlight circuit board (20) comprises a driver chip (1) and a bus expansion group (2). The driver chip (1) is configured to emit a drive control signal. The bus expansion group (2) comprises at least one bus processing module (22) and at least one bus expansion connector (24), wherein the bus expansion connector (24) is connected to the lamp area (11); and the bus processing module (22) has one end connected to the driver chip (1), and the other end connected to the bus expansion connector (24), such that the drive control signal is provided to the lamp area (11) by means of the bus processing module (22) and the bus expansion connector (24). The backlight module can implement partitioned regulation of the lamp panel (10), and improve light-regulation accuracy.

Description

Backlight module, driving method thereof and display device TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to a backlight module, a driving method thereof and a display device. BACKGROUND

[0002] A conventional LCD liquid crystal display screen is equipped with an LED as a backlight source, but a conventional LED backlight often only supports uniform adjustment and cannot achieve individual control of specific areas, which is prone to the problem of insufficient precision in partitioned light control. Therefore, Mini-LED backlight technology has emerged.

[0003] Mini-LED backlight technology is divided into two mainstream technologies: AM Mini-LED and PM Mini-LED. Compared with PM, the AM driving mode has more advantages in terms of display quality, contrast, power consumption, etc., and the AM mode can control the continuous light emission of the light source, achieve no screen flashing, and is more eye-friendly. Due to the increasing market demand for high-end display products with high partitioning, AM Mini-LED backlight technology, which has more advantages in quality and precise control, has entered a stage of rapid development.

[0004] SUMMARY

[0005] According to embodiments of the present disclosure, a backlight module, a driving method thereof and a display device are provided.

[0006] According to a first aspect of the present disclosure, a backlight module is provided, comprising: a backlight source, the backlight source comprising a lamp plate, the lamp plate comprising at least one lamp area; a backlight circuit board, the backlight circuit board comprising: a driving chip, the driving chip being configured to output a driving control signal; a bus expansion group, the bus expansion group comprising at least one bus processing module and at least one bus expansion connector, the bus expansion connector being connected to the lamp area; wherein one end of the bus processing module is connected to the driving chip, and the other end of the bus processing module is connected to the bus expansion connector, so that the driving control signal is provided to the lamp area through the bus processing module and the bus expansion connector.

[0007] In at least some embodiments, the bus processing module comprises: a bus processing chip configured to output an adjusted driving control signal; an input end connected to the bus processing chip and configured to receive a driving control signal from the driving chip and transmit the control signal to the bus processing chip; and a filter circuit connected to the input end and configured to filter the driving control signal.

[0008] In at least some embodiments, the bus processing module further comprises an output end connected to the bus processing chip and configured to transmit the driving control signal processed by the bus processing chip to the light area; and a negative pressure backflow prevention circuit comprising two transistors arranged in pairs, the two transistors comprising a first transistor and a second transistor, wherein a first end of the first transistor and a second end of the second transistor are connected to the bus processing chip, and a second end of the first transistor and a first end of the second transistor are connected to the output end.

[0009] In at least some embodiments, the bus expansion connector is provided with a plurality of connection terminals, the plurality of connection terminals comprising: an input signal terminal connected to the bus processing module and configured to transmit a signal from the bus processing module to the light area; and an output signal terminal connected to the bus processing module and configured to transmit a signal from the light area to the bus processing module.

[0010] In at least some embodiments, the plurality of connection terminals further comprise a power supply terminal configured to receive a power supply voltage from a backlight power supply.

[0011] In at least some embodiments, the backlight circuit board further comprises a backlight control circuit, the backlight control circuit comprising a backlight control connector, one end of the backlight control connector being connected to a mainboard of a display device and the other end being connected to the driving chip, wherein backlight data sent by the mainboard of the display device is transmitted to the driving chip via the backlight control connector, and the driving chip adjusts the driving control signal according to the backlight data.

[0012] In at least some embodiments, the backlight circuit board further comprises: a backlight power supply configured to supply power; and a power supply control circuit, one end of the power supply control circuit being connected to the backlight power supply and the other end being connected to at least one of the light area and the bus processing module; wherein the backlight power supply supplies power to at least one of the light area and the bus processing module via the power supply control circuit.

[0013] In at least some embodiments, the power supply control circuit comprises a power supply switching circuit configured to control the on-off of the power supply, and the power supply switching circuit comprises a first transistor and a second transistor, the first transistor comprising a first end, a second end and a third end, and the second transistor comprising a first end, a second end and a third end, wherein the third end of the first transistor is connected to the first end of the second transistor to control the on-off of the second transistor through the first transistor.

[0014] In at least some embodiments, a first end of the first transistor is configured to receive a first voltage signal from the main board to turn on the first transistor and generate a turn-on voltage at the third end configured to turn on the second transistor; a first end of the second transistor is configured to receive the turn-on voltage to turn on the second transistor; and a second end of the second transistor is configured to receive a second voltage signal from the main board and transmit the second voltage signal to the third end.

[0015] In at least some embodiments, the power supply control circuit further comprises a power supply buck circuit configured to reduce the power supply voltage provided by the power supply switching circuit to a target voltage and provide the target voltage to at least one of the lamp area and the bus processing module.

[0016] In at least some embodiments, the power supply buck circuit comprises a bus power supply buck circuit having one end connected to the power supply switching circuit and the other end connected to the bus processing module, and the bus power supply buck circuit is configured to reduce the power supply voltage to a first target voltage and provide the first target voltage to the bus processing module.

[0017] In at least some embodiments, the power supply buck circuit further comprises a lamp area power supply buck circuit having one end connected to the power supply switching circuit and the other end connected to the bus expansion connector, and the lamp area power supply buck circuit is configured to reduce the power supply voltage to a second target voltage and provide the second target voltage to the lamp area via the bus expansion connector, wherein the second target voltage is different from the first target voltage.

[0018] In at least some embodiments, the power supply control circuit further comprises a backlight power connector having one end connected to the power supply buck circuit and the other end connected to the drive chip, wherein the drive chip is further configured to send a voltage regulation signal according to the working state of the lamp area, the backlight power connector is configured to transmit the voltage regulation signal to the power supply buck circuit, and the power supply buck circuit is configured to adjust the power supply voltage of the lamp area according to the voltage regulation signal.

[0019] In at least some embodiments, the lamp panel comprises a plurality of lamp areas, the bus expansion group comprises a plurality of bus processing modules and a plurality of bus expansion connectors, the plurality of bus expansion connectors are connected to the plurality of lamp areas one by one, and the drive control signal is provided to the plurality of lamp areas via the plurality of bus processing modules and the plurality of bus expansion connectors, respectively.

[0020] According to a second aspect of the present disclosure, a display device is provided, comprising the backlight module as described above.

[0021] According to a third aspect of the present disclosure, a driving method of a backlight module is provided, comprising: a driving chip of a backlight circuit board sending a driving control signal; and the driving control signal being provided to at least one light area of a light plate via at least one bus processing module and at least one bus expansion connector.

[0022] In at least some embodiments, the driving method further comprises: a mainboard of a display device sending backlight data to a backlight control connector; the backlight control connector transmitting the backlight data to the bus processing module; and the bus processing module adjusting the driving control signal according to the backlight data.

[0023] In at least some embodiments, the driving method further comprises: the backlight power supply supplying power to at least one of the light area and the bus processing module via the power supply control circuit.

[0024] In at least some embodiments, the power supply control circuit comprises a power supply step-down circuit, and the power supply step-down circuit comprises a bus power supply step-down circuit and a light area power supply step-down circuit; wherein the backlight power supply supplying power to at least one of the light area and the bus processing module via the power supply control circuit comprises: the bus power supply step-down circuit reducing the power supply voltage to a first target voltage and providing the first target voltage to the bus processing module; and / or the light area power supply step-down circuit reducing the power supply voltage to a second target voltage and providing the second target voltage to the light area via the bus expansion connector, wherein the second target voltage and the first target voltage are different.

[0025] In at least some embodiments, the driving method further comprises: the driving chip sending a voltage regulation signal according to the working state of the light area; the backlight power supply connector transmitting the voltage regulation signal to the power supply step-down circuit; and the power supply step-down circuit adjusting the power supply voltage of the light area according to the voltage regulation signal.

[0026] In at least some embodiments, the light plate comprises a plurality of light areas, the at least one bus processing module comprises a plurality of bus processing modules, and the at least one bus expansion connector comprises a plurality of bus expansion connectors; wherein the driving control signal being provided to at least one light area of a light plate via at least one bus processing module and at least one bus expansion connector comprises: the driving control signal being provided to the plurality of light areas via the plurality of bus processing modules and the plurality of bus expansion connectors, respectively. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present disclosure and not all the embodiments of the present disclosure.

[0028] FIG. 1 is a block diagram of a backlight module according to an embodiment of the present disclosure;

[0029] FIG. 2 is a schematic diagram of a bus processing module according to an embodiment of the present disclosure;

[0030] FIG. 3 is a schematic diagram of a bus expansion connector according to an embodiment of the present disclosure;

[0031] FIG. 4 is a schematic diagram of a backlight control connector according to an embodiment of the present disclosure;

[0032] FIG. 5 is a structural block diagram of a power supply control circuit according to an embodiment of the present disclosure;

[0033] FIG. 6 is a schematic diagram of a power supply switching circuit according to an embodiment of the present disclosure;

[0034] FIG. 7 is a schematic diagram of a power supply step-down circuit according to an embodiment of the present disclosure;

[0035] FIG. 8 is a schematic diagram of a driving chip according to an embodiment of the present disclosure;

[0036] FIG. 9 is a schematic diagram of a display device according to an embodiment of the present disclosure;

[0037] FIG. 10 is a flowchart of a driving method of a backlight module according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present disclosure and not all the embodiments of the present disclosure and based on the described embodiments of the present disclosure, all other embodiments obtained by those of ordinary skill in the art without any creative work fall within the scope of protection of the present disclosure.

[0039] Unless otherwise defined, technical terms or scientific terms used herein shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terms "first", "second", and similar terms do not imply any order, quantity, or importance, but are used to distinguish one element from another, and are used arbitrarily. The terms "comprises", "comprising", "includes", "including" and the like can mean the presence of elements or objects preceding such terms in a manner consistent with the way those terms are used in the specification and claims, and permits the inclusion of additional elements or objects. The terms "connected", "coupled", and the like, can not necessarily mean physically or mechanically connected or coupled, but can include electrical connection or coupling, whether direct or indirect. The terms "upper", "lower", "left", "right", and the like, are used only to indicate relative positions, and can change accordingly when the absolute positions of the described objects change.

[0040] Conventional LED backlights usually only support uniform adjustment, and cannot achieve individual control for specific areas, and are more likely to have the problem of insufficient precision in partitioned light control.

[0041] To this end, the embodiments of the present disclosure provide a backlight module, which comprises a backlight source and a backlight circuit board. The backlight source comprises a lamp panel, and the lamp panel comprises at least one lamp area. The backlight circuit board comprises a driving chip and a bus expansion group. The driving chip is configured to send a driving control signal, and the bus expansion group comprises at least one bus processing module and at least one bus expansion connector, and the bus expansion connector is connected to the lamp area. One end of the bus processing module is connected to the driving chip, and the other end is connected to the bus expansion connector, so that the driving control signal is provided to the lamp area through the bus processing module and the bus expansion connector.

[0042] In the backlight module provided by the embodiments of the present disclosure, the bus processing module and the bus expansion connector are arranged, so that the driving control signal sent by the driving chip is provided to the lamp area through the bus processing module and the bus expansion connector, thereby achieving control of the lamp area and realizing partitioned control of the lamp panel.

[0043] The present disclosure will be described in detail through specific embodiments. In order to keep the following description of the embodiments of the present disclosure clear and concise, the detailed description of known functions and known components can be omitted. When any component of the embodiments of the present disclosure appears in more than one figure, the component can be denoted by the same reference numeral in each figure.

[0044] FIG. 1 is a block diagram of a backlight module according to an embodiment of the present disclosure. As shown in FIG. 1, the backlight module according to an embodiment of the present disclosure includes a backlight source and a backlight circuit board. The backlight source includes a lamp plate 10, and the lamp plate 10 includes at least one lamp area 11. For example, the lamp plate 10 includes a plurality of lamp areas 11 (for example, three lamp areas in FIG. 1), and the plurality of lamp areas 11 are arranged in an array. Each lamp area 11 can be provided with a plurality of Mini-LED lamps and a driver for driving each Mini-LED lamp. As shown in FIG. 1, the plurality of lamp areas 11 are arranged at intervals in the row direction, which can increase the area of the display region. It can be understood that the arrangement of the lamp areas 11 is not limited thereto, and other arrangements can also be used, which are not limited in the present disclosure.

[0045] For example, the backlight circuit board 20 includes a driver chip 1 and a bus expansion group 2. The driver chip 1 is configured to output a driving control signal. The bus expansion group 2 includes at least one bus processing module 22 and at least one bus expansion connector 24, and the bus expansion connector 24 is connected to the lamp area 11. One end of the bus processing module 22 is connected to the driver chip 1, and the other end is connected to the bus expansion connector 24, so that the driving control signal output by the driver chip 1 is provided to the lamp area 11 through the bus processing module 22 and the bus expansion connector 24, thereby realizing backlight control of the lamp area 11. In other words, by arranging the bus processing module 22 and the bus expansion connector 24, signal transmission between the driver chip 1 and the lamp area 11 can be realized.

[0046] For example, the bus expansion group 2 includes a plurality of bus processing modules 22 and a plurality of bus expansion connectors 24, and the plurality of bus processing modules 22 and the plurality of bus expansion connectors 24 are arranged one by one. In addition, the plurality of bus expansion connectors 24 and the plurality of lamp areas 11 are arranged one by one. In this way, by the plurality of bus processing modules 22 and the plurality of bus expansion connectors 24, backlight control of the plurality of lamp areas 11 can be realized respectively, and on the basis of realizing partitioned backlight control, the backlight control precision is improved.

[0047] In some embodiments, the number of bus processing modules 22, the number of bus expansion connectors 24, and the number of lamp areas 11 are equal, thereby further improving the backlight control precision.

[0048] FIG. 2 is a schematic diagram of a bus processing module according to an embodiment of the present disclosure. As shown in FIG. 2, for example, the bus processing module 22 includes a bus processing chip 200, an input end, and an output end. The bus processing chip 200 is configured to output an adjusted driving control signal. The input end is connected to the bus processing chip 200, configured to receive the driving control signal from the driver chip 1 and transmit the control signal to the bus processing chip 200. The output end is connected to the bus processing chip 200, configured to transmit the driving control signal processed by the bus processing chip 200 to the lamp area 11.

[0049] For example, the bus processing module 22 includes a first input end 201i and a first output end 201o, the first input end 201i is connected to the bus processing chip 200, used for receiving the driving control signal from the driving chip 1 and transmitting the control signal to the bus processing chip 200. The first output end 201o is connected to the bus processing chip 200, used for transmitting the driving control signal processed by the bus processing chip 200 to the lamp area 11.

[0050] For example, the bus processing module 22 further includes a second input end 202i and a second output end 202o, the second input end 202i is connected to the bus processing chip 200, used for receiving the driving control signal from the driving chip 1 and transmitting the control signal to the bus processing chip 200. The second output end 202o is connected to the bus processing chip 200, used for transmitting the driving control signal processed by the bus processing chip 200 to the lamp area 11.

[0051] FIG. 2 is illustrated by setting two input ends, it can be understood that one or more than two input ends can be set according to actual needs. In the embodiment of the present disclosure, the number of input ends is the same as the number of output ends.

[0052] For example, the bus processing module 22 further includes a filter circuit connected to the input end, used for filtering the driving control signal and removing the noise in the driving control signal.

[0053] As shown in FIG. 2, the bus processing module 22 includes a first filter circuit, the first filter circuit includes a first capacitor 203, two ends of the first capacitor 203 are connected to the first input end 201i and the ground electrode respectively, the first capacitor 203 can remove the noise on the signal line of the first input end 201i, ensuring that the signal received by the bus processing chip 200 is clear.

[0054] As shown in FIG. 2, the bus processing module 22 further includes a second filter circuit, the second filter circuit includes a second capacitor 204, two ends of the second capacitor 204 are connected to the second input end 202i and the ground electrode respectively, the second capacitor 204 can remove the noise on the signal line of the second input end 202i, ensuring that the signal received by the bus processing chip 200 is clear.

[0055] For example, the bus processing module 22 further includes a negative pressure backflow prevention circuit, including a pair of transistors, the two transistors include a first transistor and a second transistor, wherein the first end of the first transistor and the second end of the second transistor are connected to the bus processing chip, the second end of the first transistor and the first end of the second transistor are connected to the output end.

[0056] As shown in FIG. 2, the bus processing module 22 further comprises a first negative voltage backflow prevention circuit, which comprises a pair of first transistor 212 and second transistor 214, wherein the first transistor 212 comprises a first end 212a and a second end 212b, and the second transistor 214 comprises a first end 214a and a second end 214b. The first end 212a of the first transistor 212 and the second end 214b of the second transistor 214 are connected to the bus processing chip 200, and the second end 212b of the first transistor 212 and the first end 214a of the second transistor 214 are connected to the first output end 201o. The first transistor 212 and the second transistor 214 are, for example, diodes. In this way, by reversely connecting two diodes in series, only one diode can be turned on at a time, and the other diode is in an off state, so that the positive and negative voltage drops are limited to a certain voltage, thereby achieving the purpose of protecting the circuit.

[0057] As shown in FIG. 2, the bus processing module 22 further comprises a second negative voltage backflow prevention circuit, which comprises a pair of third transistor 222 and fourth transistor 224. The specific arrangement of the third transistor 222 and the fourth transistor 224 can refer to the first transistor 212 and the second transistor 214. The first end of the third transistor 222 and the second end of the fourth transistor 224 are connected to the bus processing chip 200, and the second end of the fourth transistor 224 and the first end of the third transistor 222 are connected to the second output end 202o. The third transistor 222 and the fourth transistor 224 are, for example, diodes. In this way, by reversely connecting two diodes in series, only one diode can be turned on at a time, and the other diode is in an off state, so that the positive and negative voltage drops are limited to a certain voltage, thereby achieving the purpose of protecting the circuit.

[0058] FIG. 3 is a schematic diagram of a bus expansion connector provided by an embodiment of the present disclosure. As shown in FIG. 3, the bus expansion connector 24 is provided with a plurality of connection terminals, which comprise input signal terminals and output signal terminals. For example, the input signal terminals are connected to the bus processing module 22 and transmit signals from the bus processing module 22 to the lamp area 11. The output signal terminals are connected to the bus processing module 22 and transmit signals from the lamp area 11 to the bus processing module 22.

[0059] For example, as shown in FIG. 3, the input signal terminals 241, 243 are connected to the bus processing module 22 and transmit signals from the bus processing module 22 to the lamp area 11; the output signal terminals 242, 244 are connected to the bus processing module 22 and transmit signals from the lamp area 11 to the bus processing module 22. Through the above arrangement, signal transmission between the bus processing module 22 and the lamp area 11 can be achieved, thereby improving the precision of backlight control of the lamp area.

[0060] Fig. 2 takes two input signal terminals and two output signal terminals as an example. It can be understood that one or more than two output signal terminals can be provided in the embodiments of the present disclosure, which are not limited in the embodiments of the present disclosure.

[0061] For example, the plurality of connection terminals further include a power supply terminal 245 for receiving a power supply voltage from the backlight power supply 5. In some embodiments, the power supply terminal 245 receives a stepped-down power supply voltage, and transmits the stepped-down power supply voltage to the lamp area 11 to supply power to the lamp area 11. In this way, the bus expansion connector 24 not only realizes the signal connection between the lamp area 11 and the bus processing module 22, but also provides the power supply required by the lamp area 11.

[0062] In some embodiments, the lamp area 11 can be connected to the bus expansion connector 24 through, for example, an FFC (Flexible Flat Cable) flat cable.

[0063] Fig. 4 is a schematic diagram of a backlight control connector provided by the embodiments of the present disclosure. For example, as shown in Fig. 1 and Fig. 4, the backlight circuit board 20 further includes a backlight control circuit 4, which includes a backlight control connector 41. One end of the backlight control connector 41 is connected to the main board 3 of the display device, and the other end is connected to the driving chip 1. The backlight data sent by the main board 3 of the display device is transmitted to the driving chip 1 through the backlight control connector 41, and the driving chip 1 adjusts the driving control signal according to the backlight data.

[0064] For example, as shown in Fig. 4, the backlight control connector 41 transmits the backlight data to the driving chip 1 through a backlight control bus, which can include at least one group of SPI (Serial Peripheral Interface) transmission buses and at least one group of synchronization signal transmission lines. For example, the SPI transmission bus includes a first connection terminal 411, a second connection terminal 412, a third connection terminal 413, and a fourth connection terminal 414, and the synchronization signal transmission line includes a fifth connection terminal 415 and a sixth connection terminal 416.

[0065] In the embodiment of the present disclosure, the backlight data can include backlight lighting area information and local area brightness information. In actual use, the mainboard 3 of the display device can transmit the backlight data to the driving chip 1 through the backlight control connector 41, and the driving chip 1 can adjust the backlight driving signal according to the backlight data, thereby improving the precision and contrast of the backlight control. If the driving chip 1 is not used, the above backlight data is directly sent to the driver in the lamp area, and only the SPI protocol is used for transmission, so that the number of added drivers is limited and the transmission rate is reduced. However, after the transmission through the driving chip 1, the driving chip 1 can use a higher-speed signal mode different from SPI to transmit to the bus expansion group, and then to the driver, so that the signal transmission is faster and the number of added drivers is more.

[0066] In some known backlight control schemes, the backlight control data is generated synchronously by the mainboard SOC of the display device (such as a television display) based on real-time display software algorithm. However, the main function of the mainboard core is display and external interface, and the hardware resources for backlight control generally only have a single bus interface, which is insufficient to cope with the increasingly dense direct drive chipsets.

[0067] In the embodiment of the present disclosure, the backlight data provided by the mainboard 3 is fed back to the driving chip, and the driving control signal is adjusted, thereby solving the problem of insufficient transmission capacity of the mainboard for more complex backlight data.

[0068] FIG. 5 is a structural block diagram of a power supply control circuit provided by the embodiment of the present disclosure. In combination with FIG. 1 and FIG. 5, for example, the backlight circuit board 20 further includes a backlight power supply 5 and a power supply control circuit 6. The backlight power supply 5 is used to supply power to the backlight source. One end of the power supply control circuit 6 is connected to the backlight power supply 5, and the other end is connected to at least one of the lamp area 11 and the bus processing module 22, so that the backlight power supply 5 supplies power to at least one of the lamp area 11 and the bus processing module 22 through the power supply control circuit 6.

[0069] FIG. 6 is a schematic diagram of a power supply switching circuit provided by the embodiment of the present disclosure. For example, the power supply control circuit 6 includes a power supply switching circuit 61, which is used to control the on-off of power supply and includes a first transistor 611 and a second transistor 612. The first transistor 611 includes a first end 611a, a second end 611b and a third end 611c, and the second transistor 612 includes a first end 612a, a second end 612b and a third end 612c. The third end 611c of the first transistor 611 is connected to the first end 612a of the second transistor 612, so as to control the on-off of the second transistor 611 through the first transistor 611. By setting the power supply switching circuit 61, the power supply circuit can be cut off when the backlight circuit board or the lamp area does not need power supply, thereby reducing unnecessary power consumption and reducing the energy consumption of the equipment.

[0070] In some embodiments, the first transistor 611 and the second transistor 612 are field effect transistors.

[0071] For example, the first transistor 611 is used as a switch transistor, and the second transistor 612 is used as a power transistor. The first end 611a of the first transistor 611 is used to receive the first voltage signal V1 from the main board 3, so as to turn on the first transistor 611, and generate an on voltage at the third end 611c for turning on the second transistor 612. The first end 612a of the second transistor 612 is used to receive the on voltage, so as to turn on the second transistor 612. In this way, the second end 612b of the second transistor 612 is used to receive the second voltage signal V2 from the main board 3, and transmit the second voltage signal V2 to the third end 612c. Therefore, the first voltage signal V1 is the on voltage of the first transistor 611, the second voltage signal V2 is the supply voltage, and the output end Vout of the supply switching circuit 61 outputs.

[0072] FIG. 7 is a schematic diagram of a supply voltage reduction circuit according to an embodiment of the present disclosure. For example, the supply control circuit 6 further comprises a supply voltage reduction circuit 62, which is used to reduce the supply voltage provided by the supply switching circuit 61 to a target voltage, and provide the target voltage to at least one of the lamp area 11 and the bus processing module 22.

[0073] As shown in FIG. 7, the supply voltage reduction circuit 62 comprises a bus supply voltage reduction circuit 621, one end of which is connected to the supply switching circuit 61, and the other end of which is connected to the bus processing module 22. The bus supply voltage reduction circuit 621 is used to reduce the supply voltage to a first target voltage, and provide the first target voltage to the bus processing module 22. For example, the supply voltage output from the output end Vout of the supply switching circuit 61 is input from the input end V1in of the bus supply voltage reduction circuit 621, and is output to the bus processing module 22 from the output end V1out after being converted by the bus supply voltage reduction circuit 621. In some embodiments, the supply voltage is about 12V, and the first target voltage after conversion is about 3.3V. For example, the bus supply voltage reduction circuit 621 comprises a processor U1, capacitors C1, C3 to C9, an inductor L1, and resistors R1 to R5.

[0074] As shown in FIG. 7, the power supply voltage reduction circuit 62 further comprises a lamp area power supply voltage reduction circuit 622, one end of which is connected to the power supply switching circuit 61, and the other end of which is connected to the bus expansion connector 24. The lamp area power supply voltage reduction circuit 622 is configured to reduce the power supply voltage to a second target voltage, and provide the second target voltage to the lamp area 11 through the bus expansion connector 24, wherein the second target voltage is different from the first target voltage. For example, the power supply voltage output from the output terminal Vout of the power supply switching circuit 61 is input from the input terminal V2in of the lamp area power supply voltage reduction circuit 622, and is output from the output terminal V2out of the lamp area power supply voltage reduction circuit 622 to the power supply terminal 245 (FIG. 2) of the bus expansion connector 24, and then transmitted to the lamp area 11. In some embodiments, the power supply voltage is about 12V, and the first target voltage after voltage conversion is about 3.3V±0.2V. For example, the lamp area power supply voltage reduction circuit 622 comprises a processor U2, capacitors C2, C10-C16, an inductor L2, and resistors R6-R10.

[0075] The power supply voltage of the conventional Mini LED is below 50V, so a high-power DC power supply is needed as a backlight power supply. In the embodiments of the present disclosure, by setting the power supply switching circuit and the power supply voltage reduction circuit, a low-loss high-power DC power supply can be realized, and the power supply for the lamp area 11 and the bus expansion group can be completed.

[0076] For example, as shown in FIG. 5, the power supply control circuit 6 further comprises a backlight power supply connector 63, one end of which is connected to the power supply voltage reduction circuit 62, and the other end of which is connected to the driving chip 1. The driving chip 1 is further configured to send a voltage regulation signal according to the working state of the lamp area. The backlight power supply connector 63 is configured to transmit the voltage regulation signal to the power supply voltage reduction circuit 62. The power supply voltage reduction circuit 62 is configured to adjust the power supply voltage of the lamp area according to the voltage regulation signal. For example, the backlight power supply connector 63 transmits the voltage regulation signal to the lamp area power supply voltage reduction circuit 622, and the lamp area power supply voltage reduction circuit 622 adjusts the second target voltage provided to the lamp area, thereby realizing the feedback function of the lamp area voltage. For example, the backlight power supply connector 63 comprises a power supply monitoring and feedback bus for transmitting the voltage regulation signal of the driving chip to the power supply voltage reduction circuit 62. It can be understood that according to different needs, an appropriate backlight power supply connector can be selected.

[0077] Figure 8 is a schematic diagram of a driving chip according to an embodiment of the present disclosure. As shown in Figure 8, the driving chip 1 comprises a processor and a plurality of groups of pins (e.g. 1st to 18th groups as shown in the figure) connected to the processor. Take the 1st group of pins as an example, the 1st group of pins comprises a 1st pin 1a and a 2nd pin 1b, wherein the 1st pin 1a is configured to output a driving control signal of the driving chip 1 to the bus extension group 2, and the 2nd pin 1b is configured to receive a feedback signal from the bus extension group 2, for example, a feedback signal carrying backlight data of a light zone. Therefore, the number of groups of pins is the same as the number of light zones. In Figure 8, there are 18 groups of pins, and the number of light zones is also 18.

[0078] In an embodiment of the present disclosure, the driving chip 1 is a customized MCU (Microcontroller Unit), which can process and distribute backlight bus data and has certain programming and computing capability, but does not have the capability to process high-speed image signals. For example, the driving chip has certain feedback control capability, which can output a power supply voltage adjustment signal (referred to as a voltage adjustment signal) according to the working state of the driver in the attached light zone.

[0079] For example, the driving chip 1 can also be provided with a clock circuit 101 for providing a clock reference signal. In some embodiments, the clock circuit 12 is a standard passive clock circuit.

[0080] For example, the driving chip 1 can also be provided with an LED indication circuit 102 for indicating the actual working state of the driving chip, such as system power supply, sleep, test state, and abnormal alarm state. The LED indication circuit is composed of a power supply 3.3V on the power supply board, a current limiting resistor and an LED diode.

[0081] For example, the driving chip 1 can also be provided with a manual reset and externally triggered button circuit 103.

[0082] For example, the driving chip 1 can also be provided with a register BOOT selection circuit 104 for selecting the software startup program position of the driving chip.

[0083] Figure 9 is a schematic diagram of a display device according to an embodiment of the present disclosure. For example, the display device comprises the backlight module described in any of the preceding embodiments. The display device is, for example, a liquid crystal display device. Since the backlight module described in any of the preceding embodiments is used, not only the zoning control of the backlight module of the display device can be achieved, but also the backlight control precision can be improved.

[0084] According to an embodiment of the present disclosure, a driving method of a backlight module is also provided. Figure 10 is a flowchart of the driving method of the backlight module according to an embodiment of the present disclosure. For example, the backlight module can be the backlight module described in any of the preceding embodiments. Referring to Figures 1 to 8 and 10, the driving method comprises:

[0085] Step S100: the driving chip 1 of the backlight circuit board 20 sends a driving control signal; and

[0086] Step S200: the driving control signal is provided to at least one light area 11 of the light board 10 through at least one bus processing module 22 and at least one bus expansion connector 24.

[0087] In the driving method provided by the above embodiment, the driving control signal sent by the driving chip is provided to the light area through the bus processing module and the bus expansion connector, thereby realizing the control of the light area, and thus realizing the partition regulation of the light board.

[0088] For example, the above driving method further comprises:

[0089] Step S300: the main board 3 of the display device sends backlight data to the backlight control connector 41;

[0090] Step S400: the backlight control connector 41 transmits the backlight data to the driving chip 1; and

[0091] Step S500: the driving chip 1 adjusts the driving control signal according to the backlight data.

[0092] In this way, the main board 3 of the display device can transmit the backlight data including the backlight lighting area and the backlight brightness to the driving chip 1 through the backlight control connector 41, and the driving chip 1 can adjust the backlight driving signal according to the backlight data, thereby improving the precision and accuracy of the backlight control.

[0093] For example, the backlight control connector 41 transmits the backlight data to the driving chip 1 through a backlight control bus, and the backlight control bus can include at least one group of SPI transmission bus and at least one group of synchronization signal transmission line, thereby improving the stability of signal transmission.

[0094] For example, the above driving method further comprises:

[0095] Step S600: the backlight power supply 5 supplies power to at least one of the light area 11 and the bus processing module 22 through the power supply control circuit 6.

[0096] For example, the power supply control circuit 6 includes a bus power supply step-down circuit 621 and a light area power supply step-down circuit 622. In this case, step S600 can include:

[0097] Step S601: the bus power supply step-down circuit 621 reduces the power supply voltage to a first target voltage, and provides the first target voltage to the bus processing module 22; and / or

[0098] Step S602: the lamp area power supply step-down circuit 622 reduces the power supply voltage to a second target voltage, and provides the second target voltage to the lamp area 11 via the bus expansion connector 24, wherein the second target voltage is different from the first target voltage.

[0099] For example, referring to FIG. 7, the power supply voltage output from the output terminal Vout of the power supply switching circuit 61 is input from the input terminal Vin of the bus power supply step-down circuit 621, is stepped down by the bus power supply step-down circuit 621, and is output from the output terminal Vout to the bus processing module 22. In some embodiments, the power supply voltage is about 12V, and the first target voltage after stepping down is about 3.3V.

[0100] For example, the power supply voltage output from the output terminal Vout of the power supply switching circuit 61 is input from the input terminal Vin of the lamp area power supply step-down circuit 622, is stepped down by the lamp area power supply step-down circuit 622, and is output from the output terminal Vout to the power supply terminal 245 (FIG. 2) of the bus expansion connector 24, and is further transmitted to the lamp area 11. In some embodiments, the power supply voltage is about 12V, and the first target voltage after stepping down is about 3.3V±0.2V.

[0101] For example, the power supply control circuit 6 further comprises a backlight power connector 63. In this case, the above-mentioned driving method further comprises:

[0102] Step S700: the driving chip 1 sends a voltage regulation signal according to the working state of the lamp area 11;

[0103] Step S800: the backlight power connector 63 transmits the voltage regulation signal to the power supply step-down circuit 62;

[0104] Step S900: the power supply step-down circuit 62 adjusts the power supply voltage of the lamp area 11 according to the voltage regulation signal.

[0105] Since the mainboard can monitor the power supply state of the lamp area, by feeding back the power supply state to the driving chip 1, the driving control signal can be adjusted in real time, so as to further optimize the backlight control.

[0106] In the embodiments of the present disclosure, the lamp panel 10 comprises a plurality of lamp areas 11, at least one bus processing module 22 comprises a plurality of bus processing modules 22, and at least one bus expansion connector 24 comprises a plurality of bus expansion connectors 24. In this case, step S200 further comprises:

[0107] The driving control signal is provided to the plurality of lamp areas 11 via the plurality of bus processing modules 22 and the plurality of bus expansion connectors 24, respectively.

[0108] Through the above setting, the driving control signals emitted by the same driving chip can be simultaneously distributed to the plurality of lamp areas 11 through the plurality of bus processing modules 22 and the plurality of bus expansion connectors 24, so as to realize the backlight partition control, and facilitate the separate regulation and control of the plurality of lamp areas, and improve the precision of backlight dimming.

[0109] The backlight module and the driving method thereof provided by the above embodiments of the present disclosure are especially suitable for high-end intelligent LCD screens, and can realize dynamic backlight effect at a lower cost. By setting the outer bus expansion group module, a lamp driving integrated lamp panel of closely arranged driving chip and Mini-LED is formed. By using the above backlight module, a large-size LCD display screen with 3000+ partition independent control can be realized.

[0110] In this document, the following points need to be noted:

[0111] (1) The drawings of the embodiments of the present disclosure only involve the structures involved in the embodiments of the present disclosure, and other structures can be referred to the general design.

[0112] (2) In the case of no conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0113] (3) The above is only an exemplary embodiment of the present disclosure, not for limiting the protection scope of the present disclosure, and the protection scope of the present disclosure is determined by the appended claims.

Claims

1. A backlight module, comprising: a backlight source, the backlight source comprising a lamp panel, the lamp panel comprising at least one lamp area; a backlight circuit board, the backlight circuit board comprising: a driving chip, the driving chip configured to send a driving control signal; a bus expansion group, the bus expansion group comprising at least one bus processing module and at least one bus expansion connector, the bus expansion connector connected to the lamp area; wherein one end of the bus processing module is connected to the driving chip, and the other end of the bus processing module is connected to the bus expansion connector, so that the driving control signal is provided to the lamp area through the bus processing module and the bus expansion connector.

2. The backlight module of claim 1, wherein, the bus processing module comprising: a bus processing chip, configured to output an adjusted driving control signal; an input end, connected to the bus processing chip, configured to receive a driving control signal from the driving chip and transmit the control signal to the bus processing chip; a filter circuit, connected to the input end, configured to filter the driving control signal.

3. The backlight module of claim 2, wherein, the bus processing module further comprising: an output end, connected to the bus processing chip, configured to transmit the driving control signal processed by the bus processing chip to the lamp area; a negative pressure backflow prevention circuit, comprising two transistors arranged in pairs, the two transistors comprising a first transistor and a second transistor, wherein the first end of the first transistor and the second end of the second transistor are connected to the bus processing chip, and the second end of the first transistor and the first end of the second transistor are connected to the output end.

4. The backlight module of any of claims 1 to 3, wherein, the bus expansion connector is provided with a plurality of connection terminals, the plurality of connection terminals comprising: an input signal terminal, the input signal terminal connected to the bus processing module, configured to transmit a signal from the bus processing module to the lamp area; an output signal terminal, the output signal terminal connected to the bus processing module, configured to transmit a signal from the lamp area to the bus processing module.

5. The backlight module of claim 4, wherein, the plurality of connection terminals further comprising a power supply terminal, configured to receive a power supply voltage from a backlight power supply.

6. The backlight module of any of claims 1 to 5, wherein, the backlight circuit board further comprising: a backlight control circuit, the backlight control circuit comprising a backlight control connector, one end of the backlight control connector connected to a mainboard of a display device, and the other end of the backlight control connector connected to the driving chip, wherein backlight data sent by the mainboard of the display device is transmitted to the driving chip through the backlight control connector, and the driving chip adjusts the driving control signal according to the backlight data.

7. The backlight module of any of claims 1-6, wherein, the backlight circuit board further comprising: a backlight power supply, the backlight power supply configured to supply power; a power supply control circuit, one end of the power supply control circuit connected to the backlight power supply, and the other end of the power supply control circuit connected to at least one of the lamp area and the bus processing module; wherein the backlight power supply supplies power to at least one of the lamp area and the bus processing module through the power supply control circuit.

8. The backlight module of claim 7, wherein, the power supply control circuit comprising: a power supply switching circuit configured to control on-off of the power supply, and comprising a first transistor and a second transistor, the first transistor comprising a first end, a second end and a third end, the second transistor comprising a first end, a second end and a third end, wherein the third end of the first transistor is connected to the first end of the second transistor, so as to control on-off of the second transistor through the first transistor.

9. The backlight module of claim 8, wherein the first end of the first transistor is configured to receive a first voltage signal from the main board, so as to turn on the first transistor and generate a turn-on voltage at the third end configured to turn on the second transistor; the first end of the second transistor is configured to receive the turn-on voltage, so as to turn on the second transistor; the second end of the second transistor is configured to receive a second voltage signal from the main board and transmit the second voltage signal to the third end.

10. The backlight module of claim 9, wherein, the power supply control circuit further comprises: a power supply step-down circuit configured to reduce the power supply voltage provided by the power supply switching circuit to a target voltage, and provide the target voltage to at least one of the lamp area and the bus processing module. the power supply step-down circuit comprises:

11. The backlight module of claim 10, wherein, a bus power supply step-down circuit having one end connected to the power supply switching circuit and the other end connected to the bus processing module, and configured to reduce the power supply voltage to a first target voltage and provide the first target voltage to the bus processing module. the power supply step-down circuit further comprises:

12. The backlight module of claim 10, wherein, a lamp area power supply step-down circuit having one end connected to the power supply switching circuit and the other end connected to the bus expansion connector, and configured to reduce the power supply voltage to a second target voltage and provide the second target voltage to the lamp area through the bus expansion connector, wherein the second target voltage is different from the first target voltage. the power supply control circuit further comprises:

13. The backlight module of any of claims 10-12, wherein, a backlight power connector having one end connected to the power supply step-down circuit and the other end connected to the driving chip, wherein the driving chip is further configured to send a voltage regulation signal according to the working state of the lamp area, and the backlight power connector is configured to transmit the voltage regulation signal to the power supply step-down circuit, and the power supply step-down circuit is configured to adjust the power supply voltage of the lamp area according to the voltage regulation signal. the lamp panel comprises a plurality of lamp areas, the bus expansion group comprises a plurality of bus processing modules and a plurality of bus expansion connectors, and the plurality of bus expansion connectors are connected to the plurality of lamp areas one by one; 14. The backlight module of any of claims 1-13, wherein, the driving control signal is provided to the plurality of lamp areas through the plurality of bus processing modules and the plurality of bus expansion connectors respectively.

15. A display device comprising the backlight module of any one of claims 1 to 14.

16. A driving method of a backlight module, comprising: a driving chip of a backlight circuit board sending a driving control signal; and ​ ​ The driving control signal is provided to at least one light area of the light panel via at least one bus processing module and at least one bus expansion connector.

17. The driving method of claim 16, further comprising: The main board of the display device sends backlight data to the backlight control connector; The backlight control connector transmits the backlight data to the bus processing module; The bus processing module adjusts the driving control signal according to the backlight data.

18. The driving method of claim 16 or 17, further comprising: The backlight power supply supplies power to at least one of the light area and the bus processing module via the power supply control circuit.

19. The driving method of claim 18, The power supply control circuit comprises a power supply step-down circuit, and the power supply step-down circuit comprises a bus power supply step-down circuit and a light area power supply step-down circuit; wherein, The backlight power supply supplies power to at least one of the light area and the bus processing module via the power supply control circuit, comprising: The bus power supply step-down circuit reduces the power supply voltage to a first target voltage, and provides the first target voltage to the bus processing module; and / or The light area power supply step-down circuit reduces the power supply voltage to a second target voltage, and provides the second target voltage to the light area via the bus expansion connector, wherein the second target voltage is different from the first target voltage.

20. The driving method of claim 19, further comprising: The driving chip sends a voltage regulation signal according to the working state of the light area; The backlight power supply connector transmits the voltage regulation signal to the power supply step-down circuit; The power supply step-down circuit adjusts the power supply voltage of the light area according to the voltage regulation signal.

21. The driving method of any one of claims 16 to 19, The light panel comprises a plurality of light areas, the at least one bus processing module comprises a plurality of bus processing modules, and the at least one bus expansion connector comprises a plurality of bus expansion connectors; wherein The driving control signal is provided to at least one light area of the light panel via at least one bus processing module and at least one bus expansion connector, comprising: The driving control signal is provided to the plurality of light areas via the plurality of bus processing modules and the plurality of bus expansion connectors, respectively. ​

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