CN110415654B - LED driving chip, LED driving method and liquid crystal display device - Google Patents

Abstract

The invention provides an LED driving chip, an LED driving method and a liquid crystal display device. The LED driving chip comprises a storage module, a switching module and a current adjusting module, wherein the storage module stores or updates a gradient data table; the switching module outputs a corresponding interrupt instruction according to the visual angle selection signal, and acquires and outputs corresponding gradient setting data in the gradient data table at regular time according to the interrupt instruction; the current adjusting module outputs corresponding gradient group current according to the gradient setting data to enable light emitted by the LED lamp group to form brightness gradient. The invention can switch at least two different gradient group currents to output to the LED lamp group and can replace three chips of the original control chip, single-stage boosting chip and LED driving chip, thereby reducing the potential risk of matching the three chips, leading the circuit to be simpler, leading the layout of the circuit board to be more convenient and leading the corresponding cost to be less.

Description

LED driving chip, LED driving method and liquid crystal display device

Technical Field

The invention belongs to the technical field of displays, and relates to an LED driving chip, an LED driving method and a liquid crystal display device.

Background

The conventional liquid crystal display device has a Hybrid Viewing Angle (HVA), and can switch between a Wide Viewing Angle (WVA) and a Narrow Viewing Angle (NVA). Meanwhile, the backlight source provides a backlight source at a wide viewing angle and a narrow viewing angle, and the brightness of the backlight source gradually changes in a gradient manner from the middle area to the two sides, so that the backlight source needs to drive the LED lamp sets to emit the two types of backlight according to two different sets of currents.

However, generating the two different sets of currents generally requires matching three chips, namely, a MCU (micro controller Unit), a single-stage boost chip and an LED driving chip, which has a potential risk of matching, and has the problems of complicated circuit, inconvenient layout of circuit board and correspondingly increased cost.

Disclosure of Invention

In view of the above, the present invention is directed to an LED driving chip, an LED driving method and a liquid crystal display device, which are capable of switching at least two different gradient group currents to output to an LED lamp group and replacing three original chips, namely a control chip, a single-stage boost chip and an LED driving chip, so as to reduce the potential risk of matching the three chips, make a circuit simpler, make the layout of a circuit board more convenient and reduce the corresponding cost.

The embodiment of the invention provides an LED driving chip, which comprises a storage module, a switching module and a current regulating module, wherein the storage module comprises a memory and an external communication end, and the memory is communicated with external equipment through the external communication end to store or update a gradient data table; the switching module comprises an interrupter, a timer and a register, wherein the interrupter is used for outputting a corresponding interrupt instruction when receiving an external view angle selection signal, and the register is respectively connected with the interrupter, the timer and the memory so as to periodically acquire and output corresponding gradient setting data in the gradient data table when receiving the interrupt instruction; the current adjusting module is connected with the switching module, is also connected with the LED lamps of the LED lamp group in a multi-string mode through a plurality of current output ends, and outputs corresponding gradient group current according to the gradient setting data to enable the light emitted by the LED lamp group to form brightness gradient.

Further, the registers include a reference current register and a gradient proportion register; when the register receives the interrupt instruction, the reference current register acquires and outputs a reference current value in the gradient setting data, and the gradient proportion register acquires and outputs a plurality of gradient proportions in the gradient setting data.

Further, the external communication terminal includes a serial clock terminal and a serial data terminal.

Further, the timer includes a modulation signal input terminal, an enable input terminal, a system clock receiving terminal, and a timing signal output terminal, and outputs a synchronous timing signal to the register through the timing signal output terminal after the signals are synchronously modulated according to an external modulation signal received by the modulation signal input terminal, an external enable signal received by the enable input terminal, and a system clock signal received by the system clock receiving terminal.

Furthermore, the LED driving chip further comprises a clock system connected with the timer, and the clock system is connected with the input end and the output end of an external crystal oscillator one by one through the first connecting end and the second connecting end to generate the system clock signal.

Further, the LED driving chip further comprises a voltage driving module, the voltage driving module is used for outputting LED driving voltage to the LED lamp bank through a voltage output end, the voltage driving module comprises a boosting circuit and a feedback circuit, the boosting circuit comprises a first voltage input end and a switch selection end, the first voltage input end receives first voltage, the switch selection end is connected with an external inductor, the feedback circuit is connected with the boosting circuit, and the feedback circuit controls the boosting circuit to boost the first voltage to the LED driving voltage and output the first voltage to the voltage output end.

Further, the feedback circuit automatically adjusts the magnitude of the LED driving voltage according to the output current of the current adjusting module.

Further, the LED driving chip further includes a power module, where the power module receives a second voltage through a second voltage input terminal, and provides corresponding working voltages to the storage module, the switching module, and the current regulating module.

The embodiment of the invention also provides an LED driving method, which is characterized by comprising the following steps: s1, storing or updating a gradient data table; s2, outputting a corresponding interrupt instruction according to the view angle selection signal, and acquiring and outputting corresponding gradient setting data in the gradient data table at fixed time according to the interrupt instruction; and S3, outputting corresponding gradient group current according to the gradient setting data to enable the light emitted by the LED lamp group to form brightness gradient.

The embodiment of the invention also provides a liquid crystal display device which is characterized by comprising the LED driving chip for driving the LED lamp set to generate backlight.

The LED driving chip, the LED driving method and the liquid crystal display device provided by the invention can switch at least two different gradient group currents to be output to the LED lamp group, and can replace three chips, namely an original control chip, a single-stage boosting chip and an LED driving chip, so that the potential risk of matching the three chips is reduced, the circuit is simpler, the layout of a circuit board is more convenient and the corresponding cost is lower.

In order to make the aforementioned and other objects, features and advantages of the invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

Fig. 1 is an internal composition diagram of an LED driving chip according to an embodiment of the present invention,

fig. 2 is a schematic diagram illustrating operation switching of an LED driving chip according to an embodiment of the present invention.

Fig. 3 is a two-plate gradient luminance graph generated by an LED driving chip driving an LED lamp set according to an embodiment of the invention.

Fig. 4 is a flowchart of an LED driving method according to an embodiment of the invention.

Detailed Description

To further illustrate the technical means and effects of the present invention for achieving the intended purpose, the following detailed description will be given of specific embodiments, methods, steps, structures, features and effects of the LED driving chip, the LED driving method and the liquid crystal display device according to the present invention with reference to the accompanying drawings and preferred embodiments.

The foregoing and other aspects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments, as illustrated in the accompanying drawings. While the invention has been described in connection with specific embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention.

Fig. 1 is an internal composition diagram of an LED driving chip according to an embodiment of the invention. The present embodiment provides an LED driving chip, as shown in fig. 1, the LED driving chip includes a storage module 100, a switching module 200 and a current adjusting module 300, the storage module 100 includes a memory 110 and an external communication terminal 120, the memory 110 communicates with an external device through the external communication terminal 120 to store or update a gradient data table; the switching module 200 includes an interrupter 210, a timer 220, and a register 230, wherein the interrupter 210 is configured to output a corresponding interrupt instruction when receiving an external view selection signal, and the register 230 is respectively connected to the interrupter 210, the timer 220, and the memory 110, so as to periodically acquire and output corresponding gradient setting data in the gradient data when receiving the interrupt instruction; the current adjusting module 300 is connected to the switching module 200, and further connected to the LED lamp sets 700 through a plurality of current output terminals (301, 302 … 30n), and outputs gradient set currents according to the gradient setting data to form a brightness gradient of the light emitted from the LED lamp sets 700.

Specifically, in the present embodiment, the light emitted from the LED lamp set 700 is a brightness gradient gradually formed from the middle area to both sides. In other embodiments, the light emitted from the LED lamp set 700 may also realize a brightness gradient gradually increasing or decreasing from one side to the other side, which may be set separately according to the design requirement and the display requirement, and is not limited herein.

Specifically, in this embodiment, the memory module 100 may include a memory 110 and an external communication terminal 120, the memory 110 may store a gradient data table, the gradient data table includes gradient setting data for setting currents of the light strings of the LED light set 700, the external communication terminal 120 may be configured to communicate with an external device, and the external device may enable the memory 110 to store or update the gradient data table through the external communication terminal 120. In one embodiment, the gradient data table may include a plurality of gradient setting data tables to read one of the gradient setting data tables according to the interrupt instruction. In one embodiment, the external device may be further electrically connected to the register 230 through the external communication terminal 120 to read data of the register 230, set a working instruction of the register 230, and the like.

In one embodiment, the external communication terminal 120 includes a serial clock terminal 121 and a serial data terminal 122, and the external communication terminal 120 may be connected to an external device through an I2C bus, but the present invention is not limited to the I2C bus, and may also be connected to an external device through an SPI bus or a UART bus.

In this embodiment, the switching module 200 includes an interrupter 210, a timer 220, and a register 230. The interrupter 210 is configured to output a corresponding interrupt instruction when receiving an external view angle selection signal. The present embodiment will be described below by taking an example in which the viewing angle selection signals include a first viewing angle selection signal V1 and a second viewing angle selection signal V2. The interrupter 210 receives an external view angle selection signal as a first view angle selection signal V1 and outputs an interrupt command as a first interrupt command when displayed at a first view angle (e.g., a wide view angle), or the interrupter 210 receives an external view angle selection signal as a second view angle selection signal V2 and outputs an interrupt command as a second interrupt command when displayed at a second view angle (e.g., a narrow view angle). The register 230 is connected to the interrupter 210, the timer 220, and the memory 110, respectively, and upon receiving a first interrupt instruction output from the interrupter 210, the corresponding gradient setup data in the gradient data table of the memory 110 i.e. the first gradient setup data may be synchronously read according to the rising edge (or falling edge) of the timing clock signal output by the timer 220, to periodically acquire first gradient setting data and may output the read first gradient setting data to the current regulation module 300, or, upon receiving the second interrupt instruction output by the interrupt 210, the corresponding gradient setting data in the gradient data table of the memory 110, i.e. the second gradient setting data, may be synchronously read according to the rising edge (or the falling edge) of the timing clock signal output by the timer 220, to periodically acquire the second gradient setting data and may output the read second gradient setting data to the current adjusting module 300.

In an embodiment, registers 230 may include a reference current register and a gradient proportion register; the register 230 acquires and outputs a reference current value in the gradient setting data by the reference current register and a plurality of gradient proportions in the gradient setting data by the gradient proportion register when receiving the interrupt instruction. The gradient setting data may include a reference current value and a plurality of gradient proportions, and the gradient group current may be obtained by multiplying the reference current value by the plurality of gradient proportions. Specifically, registers 230 may include a reference current register and a gradient proportion register; when the interrupt instruction received by the register 230 is a first interrupt instruction, the register may obtain and output corresponding gradient setting data, that is, first gradient setting data, the reference current register may obtain and output a first reference current value in the first gradient setting data, and the gradient proportion register may obtain and output a plurality of first gradient proportions in the first gradient setting data; when the interrupt instruction is received as the second interrupt instruction, the register 230 may acquire and output corresponding gradient setting data, that is, second gradient setting data, the reference current register may acquire and output a second reference current value in the second gradient setting data, and the gradient proportion register may acquire and output a plurality of second gradient proportions in the second gradient setting data.

In an embodiment, the timer 220 may include a modulation signal input terminal 221, an enable input terminal 222, a system clock receiving terminal 223, and a timing signal output terminal 224, and output a synchronous timing signal to the register 230 through the timing signal output terminal 224 after the signal is synchronously modulated according to an external modulation signal received by the modulation signal input terminal 221, an external enable signal received by the enable input terminal 222, and a system clock signal received by the system clock receiving terminal 223.

In an embodiment, the LED driving chip may further include a clock system 500 connected to the timer 220, wherein the clock system 500 is connected to the input and output terminals of the external crystal oscillator one by one through a first connection terminal 501 and a second connection terminal 502 to generate a system clock signal.

In this embodiment, the current adjusting module 300 is connected to the switching module 200, and further connected to the LED lamp sets 700 through a plurality of current output terminals (301, 302 … 30n), and outputs a first gradient set current according to the first gradient setting data to make the light emitted from the LED lamp set 700 gradually form a first brightness gradient from the middle to both sides, or outputs a second gradient set current according to the second gradient setting data to make the light emitted from the LED lamp set 700 gradually form a second brightness gradient from the middle to both sides, for example, the first gradient set current is 8 gradient current values according to the first gradient setting data, and IFB1 to IFB8 are 20mA, 19mA, 18mA, 17.2mA, 16.4mA, 15.6mA, 14.8mA and 14mA respectively, so that the currents of the LED lamp set 700 from both sides to the middle are 20mA, 19mA, 18mA, 17.2, 16.4, 15.6mA, 14.8mA and 14mA respectively, therefore, the brightness of the LED lamps at the two sides is the largest, the brightness of the LED lamp at the middle is the smallest, and the brightness gradient from the middle to the LED lamps at the two sides is increased, so that the light emitted by the LED lamp set 700 gradually forms the first brightness gradient from the middle to the two sides.

In an embodiment, the first gradient setting data may include a first reference current value and a plurality of first gradient proportions, the first gradient group current may be obtained by multiplying the first reference current value by the plurality of first gradient proportions, the second gradient setting data may include a second reference current value and a plurality of second gradient proportions, and the second gradient group current may be obtained by multiplying the second reference current value by the plurality of second gradient proportions.

In an embodiment, the LED driving chip may further include a voltage driving module 400, the voltage driving module 400 is configured to output an LED driving voltage to the LED lamp set 700 through a voltage output terminal, the voltage driving module 400 may include a voltage boosting circuit 410 and a feedback circuit 420, the voltage boosting circuit 410 may include a first voltage input terminal 411 and a switch selection terminal 412, the first voltage input terminal 411 receives a first voltage, the switch selection terminal 412 is connected to an external inductor, the feedback circuit 420 is connected to the voltage boosting circuit 410, and the feedback circuit 420 controls the voltage boosting circuit 410 to boost the first voltage to the LED driving voltage and output the LED driving voltage to the voltage output terminal.

In this embodiment, the voltage boost circuit 410 in the voltage driving module 400 may turn on and off an internal switching element according to a corresponding pulse width modulation signal, so as to boost the first voltage received by the first voltage input terminal 411 to an LED driving voltage, and output the LED driving voltage to the LED lamp set 700 through a voltage output terminal, so that each string of LED lamps of the LED lamp set 700 receives the LED driving voltage, generates a corresponding current according to the voltage, and emits a brightness corresponding to the current.

In one embodiment, the feedback circuit 420 may automatically adjust the magnitude of the LED driving voltage according to the output current of the current adjusting module 300. For example, the current adjusting module 300 obtains the first gradient setting data from the register 230, and adjusts and outputs a corresponding first gradient group current, where the first gradient group current is, for example, 8 gradient current values, and IFBs 1 to IFB8 are respectively 20mA, 19mA, 18mA, 17.2mA, 16.4mA, 15.6mA, 14.8mA, and 14mA, and then the currents on the LED lamps in each string of the LED lamp group 700 are all large, and the feedback circuit 420 adjusts accordingly, so that the LED driving voltage output by the voltage boosting circuit 410 is increased; after the view angle switching is performed, the current adjusting module 300 obtains the second gradient setting data from the register 230, and adjusts and outputs a corresponding second gradient group current, where the second gradient group current is, for example, 8 gradient current values, and the IFBs 1 to 8 are respectively 4.9mA, 5.18mA, 5.46mA, 5.74mA, 6.02mA, 6.3mA, 6.65mA and 7mA, so that the currents on the LED lamps in each string of the LED lamp group 700 are all small, and the feedback circuit 420 performs corresponding adjustment, so that the LED driving voltage output by the voltage boosting circuit 410 is reduced.

In an embodiment, the LED driving chip may further include a power module 600, and the power module 600 receives a second voltage through a second voltage input terminal and provides corresponding operating voltages for the storage module 100, the switching module 200 and the current regulating module 300. In one embodiment, the power module 600 may be grounded through a ground terminal.

Specifically, the working mode of the LED driving chip of this embodiment can refer to fig. 2, and fig. 2 is a schematic diagram of the work switching of the LED driving chip according to an embodiment of the present invention. As shown in fig. 2, when the first view angle display is performed, the interrupter 210 of the switching module 200 receives the external view angle selection signal as the first view angle selection signal V1, for example, a low level signal, the interrupter 210 outputs a corresponding interrupt instruction as the first interrupt instruction to the register 230, and the register 230 updates the first gradient setting data according to the first interrupt instruction through the timer 220, that is, the first gradient setting data is obtained from the memory 110 of the storage module 100 at regular time. The memory 110 communicates with an external device through the external communication terminal 120 to obtain, for example, a gradient data table, and obtain, store or update corresponding first gradient setting data and second gradient setting data. In an embodiment, the first gradient setting data may include a first reference current value and a plurality of first gradient proportions, and the first reference current value may be set and modified in the memory 110 by an external device in a range of 3mA to 25mA, and the plurality of first gradient proportions may also be set to 8 or 10, and the embodiment does not limit the number of the first gradient proportions; also, the registers 230 may include a reference current register that may store or update the first reference current value accordingly and a gradient proportion register that may store or update the plurality of first gradient proportions accordingly.

The register 230 may output the first gradient setting data to the current adjusting module 300 after receiving the first gradient setting data, and in an embodiment, the register 230 outputs a first reference current value to the current adjusting module 300 through the reference current register and outputs a plurality of first gradient ratios to the current adjusting module 300 through the gradient ratio register. The current adjusting module 300 outputs a first gradient group current through a plurality of current output terminals (301, 302 … 30n) according to the first gradient setting data, so that the light emitted from the LED light group 700 gradually forms a first brightness gradient from the middle to both sides. When the current adjusting module 300 outputs the first gradient set current, the voltage driving module 400 also outputs the LED driving voltage to the LED lamp set 700 through the voltage output terminal, so as to drive the LED lamps of the LED lamp set 700 to be turned on and generate the corresponding current.

When the second view angle display is performed, the interrupter 210 of the switching module 200 receives the external view angle selection signal as the second view angle selection signal V2, for example, a high level signal, the interrupter 210 outputs an interrupt instruction as a second interrupt instruction to the register 230, and the register 230 updates the second gradient setting data through the timer 220 according to the second interrupt instruction, that is, the second gradient setting data is obtained from the memory 110 of the storage module 100 at regular time. The memory 110 communicates with an external device through the external communication terminal 120 to obtain, for example, a gradient data table, and obtain, store or update corresponding first gradient setting data and second gradient setting data. In an embodiment, the second gradient setting data may include a second reference current value and a plurality of second gradient proportions, and the second reference current value may be set and modified in the memory 110 by an external device in a range of 3mA to 25mA, and the plurality of second gradient proportions may also be set to 8 or 10, and the embodiment does not limit the number of the second gradient proportions; also, the registers 230 may include a reference current register that may store or update the second reference current value accordingly and a gradient proportion register that may store or update a plurality of second gradient proportions accordingly.

The register 230 may output the second gradient setting data to the current adjusting module 300 after receiving the second gradient setting data, and in an embodiment, the register 230 outputs a second reference current value to the current adjusting module 300 through the reference current register and outputs a plurality of second gradient proportions to the current adjusting module 300 through the gradient proportion register. The current adjusting module 300 outputs a second gradient group current through a plurality of current output terminals (301, 302 … 30n) according to the second gradient setting data, so that the light emitted from the LED light group 700 gradually forms a second brightness gradient from the middle to both sides. When the current adjusting module 300 outputs the second gradient set current, the voltage driving module 400 also outputs the LED driving voltage to the LED lamp set 700 through the voltage output terminal, so as to drive the LED lamps of the LED lamp set 700 to be turned on and generate the corresponding current.

When the LED driving chip of this embodiment displays at the first viewing angle and the second viewing angle, the LED lamp set 700 generates the first brightness gradient and the second brightness gradient, that is, the two versions of brightness gradients can be selected for the viewing angle display, and the two versions of brightness gradients are different from each other, so that the image can be better displayed at the two viewing angles.

For example, in an embodiment, when the LED driving chip displays at two viewing angles, the corresponding first reference current value, the plurality of first gradient ratios, the second reference current value, and the plurality of second gradient ratios in the reference current register and the gradient ratio register of the register 230 are respectively shown in table 1, so that the current gradients at the two viewing angles are shown in table 2, and fig. 3 can be referred to, where fig. 3 is a two-version gradient luminance graph generated by the LED driving chip according to an embodiment of the present invention.

Table 1:

table 2:

as can be seen from fig. 3, the LED driving chip of this embodiment can generate two different brightness gradients, and can be used for two viewing angles, respectively. When the LED lamps at the two sides are displayed at the first visual angle, the brightness of the LED lamps at the two sides is the largest, the brightness of the LED lamp at the middle is the smallest, and the brightness gradient from the middle to the LED lamps at the two sides is increased, so that the light emitted by the LED lamp set 700 gradually forms a first brightness gradient from the middle to the two sides; when the display is performed at the second viewing angle, the brightness of the LED lamps at the two sides is the minimum, the brightness of the LED lamp at the middle is the maximum, and the brightness gradient from the middle to the LED lamps at the two sides is reduced, so that the light emitted by the LED lamp set 700 gradually forms a second brightness gradient from the middle to the two sides.

The LED driving chip of this embodiment can switch at least two different gradient sets of currents to output to the LED lamp set 700, and can replace three chips, namely, the original control chip, the single-stage boost chip, and the LED driving chip, thereby reducing the potential risk of three chip collocation, and the circuit is simpler, and the layout of the circuit board is more convenient and the corresponding cost is less.

The embodiment of the present invention is further based on the same inventive concept, and provides an LED driving method, fig. 4 is a flowchart of the LED driving method according to an embodiment of the present invention, and as shown in fig. 4, the driving method includes the steps of:

s1, storing or updating a gradient data table;

s2, outputting a corresponding interrupt instruction according to the view angle selection signal, and acquiring and outputting corresponding gradient setting data in a gradient data table at fixed time according to the interrupt instruction;

and S3, outputting corresponding gradient group current according to the gradient setting data to enable the light emitted by the LED lamp group to form brightness gradient.

The implementation of the LED driving method can refer to the above embodiments of the LED driving chip, and repeated descriptions are omitted.

The LED driving method of this embodiment can switch at least two different gradient group currents to output to the LED lamp group 700, and the driving chip using the driving method can replace the original three chips, i.e., the control chip, the single-stage boost chip, and the LED driving chip, thereby reducing the potential risk of matching the three chips, making the circuit simpler, making the layout of the circuit board more convenient, and reducing the corresponding cost.

The embodiment of the invention is also based on the same inventive concept, and provides a liquid crystal display device, which comprises the LED driving chip, and drives the LED lamp set 700 to generate backlight. For the specific implementation of this embodiment, reference may be made to the implementation of the LED driving chip described above, and details are not described here.

The liquid crystal display device of the embodiment can switch at least two different gradient group currents to output to the LED lamp group 700, and can replace three original chips, namely a control chip, a single-stage boosting chip and an LED driving chip, so that the potential risk of matching of the three chips is reduced, the circuit is simpler, the layout of a circuit board is more convenient, and the corresponding cost is lower.

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (9)

1. An LED driver chip for driving an LED lamp set (700), the LED driver chip comprising:

a storage module (100), wherein the storage module (100) comprises a memory (110) and an external communication terminal (120), and the memory (110) is communicated with an external device through the external communication terminal (120) to store or update a gradient data table;

a switching module (200), wherein the switching module (200) comprises an interrupter (210), a timer (220) and a register (230), the interrupter (210) is used for outputting a corresponding interrupt instruction when receiving an external view angle selection signal, and the register (230) is respectively connected with the interrupter (210), the timer (220) and the memory (110) so as to periodically acquire and output corresponding gradient setting data in the gradient data table when receiving the interrupt instruction;

the current adjusting module (300) is connected with the switching module (200), is also connected with the LED lamps of the LED lamp group (700) one by one through a plurality of current output ends, and outputs corresponding gradient group current according to the gradient setting data to enable the light emitted by the LED lamp group (700) to form brightness gradient;

wherein the register (230) comprises a reference current register and a gradient proportion register, the reference current register acquires and outputs a reference current value in the gradient setting data when the register (230) receives the interrupt instruction, and the gradient proportion register acquires and outputs a plurality of gradient proportions in the gradient setting data.

2. The LED driving chip according to claim 1, wherein the external communication terminal (120) comprises a serial clock terminal (121) and a serial data terminal (122).

3. The LED driving chip according to claim 1, wherein the timer (220) comprises a modulation signal input terminal (221), an enable input terminal (222), a system clock receiving terminal (223) and a timing signal output terminal (224), and outputs a synchronous timing signal to the register (230) through the timing signal output terminal (224) after signal synchronous modulation according to an external modulation signal received by the modulation signal input terminal (221), an external enable signal received by the enable input terminal (222) and a system clock signal received by the system clock receiving terminal (223).

4. The LED driver chip according to claim 3, further comprising a clock system (500) connected to the timer (220), wherein the clock system (500) is connected to the input and output terminals of the external crystal oscillator one by one through a first connection terminal (501) and a second connection terminal (502) to generate the system clock signal.

5. The LED driving chip according to claim 1, further comprising a voltage driving module (400), wherein the voltage driving module (400) is configured to output an LED driving voltage to the LED lamp set (700) through a voltage output terminal; the voltage driving module (400) comprises a boosting circuit (410) and a feedback circuit (420), the boosting circuit (410) comprises a first voltage input end (411) and a switch selection end (412), the first voltage input end (411) receives a first voltage, the switch selection end (412) is connected with an external inductor, the feedback circuit (420) is connected with the boosting circuit (410), and the feedback circuit (420) controls the boosting circuit (410) to boost the first voltage to the LED driving voltage and output the first voltage to the voltage output end.

6. The LED driving chip according to claim 5, wherein the feedback circuit (420) automatically adjusts the magnitude of the LED driving voltage according to the output current of the current adjusting module (300).

7. The LED driver chip according to claim 1, further comprising a power supply module (600), wherein the power supply module (600) receives a second voltage through a second voltage input terminal and provides respective operating voltages for the storage module (100), the switching module (200) and the current regulation module (300).

8. An LED driving method for driving the LED driving chip according to any one of claims 1 to 7, comprising the steps of:

s1, storing or updating a gradient data table;

s2, outputting a corresponding interrupt instruction according to the view angle selection signal, and acquiring and outputting corresponding gradient setting data in the gradient data table at fixed time according to the interrupt instruction;

and S3, outputting corresponding gradient group current according to the gradient setting data to enable the light emitted by the LED lamp group to form brightness gradient.

9. A liquid crystal display device, comprising the LED driving chip according to any one of claims 1 to 7 for driving the LED lamp set (700) to generate backlight.

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