Clock synchronization method of backlight chip, backlight module and display equipment

Abstract

The embodiment of the invention provides a clock synchronization method of a backlight chip, a backlight module and display equipment, and relates to the technical field of display. The method comprises the steps that a first counting value of a main backlight chip in a first counting duration and a second counting value of a slave backlight chip in a second counting duration are obtained, and the first counting value and the second counting value are both obtained by the backlight chips through accumulative counting based on clock sources of the backlight chips; according to the first count value and the second count value, determining a frequency error of the slave backlight chip and the master backlight chip; and adjusting the frequency of the slave backlight chip based on the frequency error. According to the embodiment of the invention, the frequency error between the two backlight chips is obtained through the communication protocol between the backlight chips, and the frequency of the slave backlight chip is adjusted based on the frequency error, so that the precise clock synchronization of the master and slave devices is realized, and the consistency and stability of the display effect are improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a clock synchronization method for a backlight chip, a backlight module, and a display device. Background Art

[0002] Mini-LED is a new type of LED display technology. Compared with traditional LCD screen backlight, Mini-LED technology can make LED backlight beads very small. It can integrate more backlight beads on the same screen, divide more backlight partitions, and achieve more precise regional light adjustment, effectively improve screen brightness and contrast, while controlling the display of dark areas, and making the colors more saturated. The LED backlight beads of each backlight partition are driven by a backlight driver chip. The clock synchronization of the backlight driver chip is a key technology to ensure the consistent and stable display effect of all backlight partitions. For example, clock synchronization has the functions of ensuring consistent output time in black frame insertion, improving the accuracy of the timer when delaying data output, and ensuring the consistency of PWM output timing from the device. Summary of the invention

[0003] The embodiments of the present application provide a clock synchronization method for a backlight chip, a backlight module, and a display device to achieve precise clock synchronization between a master and a slave device, thereby improving the consistency and stability of the display effect.

[0004] In a first aspect, an embodiment of the present application provides a clock synchronization method for a backlight chip, which is applied to control the clock signal synchronization of at least two backlight chips, and the method includes:

[0005] Obtaining a first count value of the master backlight chip within a first count duration, and a second count value of the slave backlight chip within a second count duration, wherein the first count value and the second count value are both obtained by cumulative counting of the backlight chip based on its own clock source;

[0006] Determine a frequency error between the slave backlight chip and the master backlight chip according to the first count value and the second count value;

[0007] Based on the frequency error, adjust the frequency from the backlight chip.

[0008] In a possible implementation manner, obtaining a first count value of a master backlight chip within a first count duration, and a second count value of a slave backlight chip within a second count duration, includes:

[0009] The slave backlight chip receives a first command sent by the master backlight chip, and starts counting according to the first command;

[0010] After the second counting time, the slave backlight chip receives the second command sent by the master backlight chip and the first count value of the master backlight chip within the first counting time, stops counting according to the second command, and determines the second count value.

[0011] In a possible implementation manner, the first counting duration is equal to the second counting duration; accordingly, determining the frequency error between the slave backlight chip and the master backlight chip according to the first counting value and the second counting value includes:

[0012] Determining a count difference value according to the first count value and the second count value;

[0013] The frequency error between the slave backlight chip and the master backlight chip is determined according to the count difference and the first count value.

[0014] In a possible implementation, determining the frequency error between the slave backlight chip and the master backlight chip according to the first count value and the second count value includes:

[0015] Determining a first frequency of the main backlight chip according to the first counting value and the first counting duration;

[0016] Determining a second frequency of the slave backlight chip according to the second count value and the second count duration;

[0017] The frequency error between the slave backlight chip and the master backlight chip is determined according to the first frequency and the second frequency.

[0018] In a possible implementation, adjusting the frequency of the slave backlight chip based on the frequency error includes:

[0019] Based on the frequency error, circuit parameters of the phase-locked loop circuit of the slave backlight chip are adjusted to make the clock frequency of the slave backlight chip match the clock frequency of the master backlight chip.

[0020] In a possible implementation manner, the communication protocol adopted between the master backlight chip and the slave backlight chip is one or more combinations of the following communication protocols, wherein the following communication protocols include single-wire transmission protocol, SPI and I2C.

[0021] In a second aspect, an embodiment of the present application provides a backlight module, the backlight module includes at least two backlight units, each backlight unit includes a backlight chip;

[0022] The backlight chips of at least two backlight units are connected;

[0023] The slave backlight chip of the backlight chips of at least two backlight units adjusts the frequency of the slave backlight chip according to the first count value of the master backlight chip in the first count duration and the second count value of the slave backlight chip in the second count duration.

[0024] In a possible implementation, after the master backlight chip starts counting, it sends a first command to the slave backlight chip, and the slave backlight chip starts counting based on the first command;

[0025] After the first counting time, the master backlight chip stops counting, determines a first count value, and sends the first count value and a second command to the slave backlight chip. The slave backlight chip stops counting based on the second command and determines a second count value.

[0026] In a possible implementation manner, the first counting duration is equal to the second counting duration; and the slave backlight chip adjusts the frequency of the slave backlight chip according to the first counting value and the second counting value.

[0027] In a third aspect, an embodiment of the present application provides a display device, comprising a liquid crystal panel and a backlight module as in any one of the above embodiments; the backlight module executes a clock synchronization method of a backlight chip as in any one of the above embodiments.

[0028] The clock synchronization method of the backlight chip, the backlight module and the display device provided in the embodiment of the present application, wherein the method comprises: obtaining a first count value of the master backlight chip within a first count duration, and a second count value of the slave backlight chip within a second count duration, wherein the first count value and the second count value are both obtained by cumulative counting of the backlight chip based on its own clock source; determining the frequency error between the slave backlight chip and the master backlight chip according to the first count value and the second count value; and adjusting the frequency of the slave backlight chip based on the frequency error. The embodiment of the present application obtains the frequency error between the two backlight chips through the communication protocol between the backlight chips, adjusts the frequency of the slave backlight chip based on the frequency error, and realizes precise clock synchronization of the master and slave devices, thereby improving the consistency and stability of the display effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0030] Figure 1 A schematic diagram of a scenario of a clock synchronization method for a backlight chip provided in the present application;

[0031] Figure 2 A schematic diagram of a clock synchronization method for a backlight chip provided in one embodiment of the present application Figure 1 ;

[0032] Figure 3 Schematic diagram of the information interaction process between the master and slave backlight chips provided in one embodiment of the present application Figure 1 ;

[0033] Figure 4Schematic diagram of the information interaction process between the master and slave backlight chips provided in one embodiment of the present application Figure 2 ;

[0034] Figure 5 A schematic diagram of a clock synchronization method for a backlight chip provided in one embodiment of the present application Figure 2 .

[0035] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0036] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0037] In the accompanying drawings, the thickness of multiple layers and regions is shown in an enlarged manner to make it clear and easy to describe. When a layer, region or plate is referred to as "on" another layer, region or plate or "adjacent to" another layer, region or plate, it can be directly on another layer, region or plate, or there can be an intermediate layer, region or plate between them. On the contrary, when a layer, region or plate is referred to as "directly on" another layer, region or plate or "close to" another layer, region or plate, there can be no intermediate layer, region or plate between them. In addition, when a layer, region or plate is referred to as "below" another layer, region or plate, it can be "directly below" another layer, region or plate, or there can be an intermediate layer, region or plate between them. On the contrary, when a layer, region or plate is referred to as "directly below" another layer, region or plate, there can be no intermediate layer, region or plate between them.

[0038] For ease of description, spatially relative terms such as "below", "beneath", "below", "above", "above", etc. may be used herein to describe the relationship between one element or component and another element or component as shown in the drawings. It will be understood that in addition to the orientations illustrated in the drawings, the spatially relative terms are intended to encompass different orientations of the device in use or operation. For example, where the device shown in the figure is flipped, a device that is "below" or "below" another device may be placed "above" the other device. Thus, the exemplary term "below" may include a lower position and an upper position. The device may also be oriented in another direction, so the spatially relative terms may be interpreted differently depending on the orientation.

[0039] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances. Throughout the specification, when an element is referred to as "connected" to another element, the element is "directly connected" to the other element, or "electrically connected" to the other element with one or more intermediate elements inserted therebetween.

[0040] The terms used herein are only used for the purpose of describing specific embodiments, and are not restrictive. As used herein, the singular form "one" is intended to also include the plural form, unless the context clearly indicates otherwise. It will be further understood that when used in this specification, the terms "include" and / or "comprise" specify the presence of features, integral bodies, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integral bodies, steps, operations, elements, components and / or their groups. As used herein, the term "and / or" includes any and all combinations of one or more associated listed items. Expressions such as "at least one" before the element list modify the entire element list without modifying the individual elements of the list.

[0041] It should be understood that in the description of the present application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0042] As used herein, "about," "substantially," "approximately," and similar terms include the stated value and mean within an acceptable range of deviation for a particular value determined by one of ordinary skill in the art, taking into account the measurement in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system). For example, "about" can mean within one or more standard deviations, or within ±30%, ±20%, ±10%, ±5% of a value. In addition, when describing embodiments of the present application, the use of "can" refers to "one or more embodiments of the present disclosure." As used herein, the term "using" can be considered to be a synonym for the term "utilizing," respectively.

[0043] According to the electronic or electrical devices and / or any other related devices or components of the embodiments of the present application described herein, such as, for example, external controllers, timing controllers, data drivers, scan drivers, grayscale voltage generators, grayscale correctors, and emission drivers can be implemented using any suitable hardware, firmware (e.g., dedicated integrated circuits), software, or a combination of software, firmware, and hardware known to those of ordinary skill in the art. For example, the various components of these devices can be formed on an integrated circuit (IC) chip or on separate IC chips. In addition, the various components of these devices can be implemented on a flexible printed circuit film, a tape carrier package (TCP), a printed circuit board (PCB), or formed on a substrate. In addition, the various components of these devices can be processes or threads running on one or more processors in one or more computing devices, executing computer program instructions and interacting with other system components for performing various functionalities described herein. The computer program instructions are stored in a memory, which can be implemented in a computing device using a standard memory device such as a random access memory (RAM). The computer program instructions can also be stored in other non-temporary computer-readable media, such as, for example, a CD-ROM or a flash drive. In addition, one of ordinary skill in the art should recognize that the functionality of various computing / electronic devices may be combined or integrated into a single computing / electronic device, or the functionality of a particular computing / electronic device may be distributed across one or more computing / electronic devices without departing from the spirit and scope of the present application.

[0044] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and will not be understood as an ideal or overly formal meaning unless explicitly defined in this specification.

[0045] First of all, the clock signal refers to a timing signal in the chip, which is used to know the working rhythm of the chip and synchronize the working status of each component. Simply put, the clock signal is a regular oscillation signal that controls the working speed and action sequence of each part of the chip. For example, the registers, timing circuits, data paths, etc. inside the CPU all need to work according to the rhythm of the clock signal. Therefore, it is very important for the chip to need a clock signal. The role of the clock signal is not only to control the working status of the internal components of the chip, but also to improve the efficiency and performance of the equipment, save energy consumption, increase the stability of the equipment, and so on.

[0046] Mini-LED, which stands for "sub-millimeter light-emitting diode" in Chinese, is a new type of LED display technology. Compared with traditional LCD screen backlight, Mini-LED technology can make LED backlight beads very small, and can integrate more backlight beads on the same screen, divide more backlight partitions, and achieve more precise regional light adjustment, effectively improving screen brightness and contrast, while controlling the display of dark areas, and making the colors more saturated. In Mini-LED, the LED backlight beads of each backlight partition are driven by a backlight driver chip. The clock synchronization of the backlight driver chip is a key technology to ensure the consistent and stable display effects of all backlight partitions. For example, clock synchronization has the functions of ensuring consistent output time in black frame insertion, improving the accuracy of the timer when delaying data output, and ensuring the consistency of PWM output timing from the device.

[0047] In view of the above technical problems, the present application provides a clock synchronization method for a backlight chip, which is applied to control the clock signal synchronization of at least two backlight chips, such as Figure 1 As shown, at least two backlight chips include a master backlight chip 101 and a slave backlight chip 102, and the master backlight chip 101 communicates with the slave backlight chip 102. Figure 2 As shown, taking the clock synchronization method of the backlight chip applied to the slave backlight chip 102 as an example, the method includes:

[0048] Step 202, obtaining a first count value of the master backlight chip within a first count duration, and a second count value of the slave backlight chip within a second count duration, wherein the first count value and the second count value are both obtained by accumulating counts of the backlight chip based on its own clock source;

[0049] Step 204, determining a frequency error between the slave backlight chip and the master backlight chip according to the first count value and the second count value;

[0050] Step 206, adjusting the frequency of the slave backlight chip based on the frequency error.

[0051] The master backlight chip is the backlight chip set as the main clock source, and the slave backlight chip needs to be synchronized with the master backlight chip clock. In the embodiment of the present application, the master backlight chip and the slave backlight chip are relative. For example, to avoid the synchronization of other backlight chips being affected when the master backlight chip fails, the master backlight chip is not fixed. During synchronization, one of the backlight chips is randomly selected as the master backlight chip, and the clock synchronization between the backlight chips is achieved according to the clock synchronization method provided in the embodiment of the present application. If at least two backlight chips are connected to other devices and receive input data or commands from other devices, the master backlight chip is determined based on the other devices.

[0052] There may be multiple master backlight chips and multiple slave backlight chips in at least two backlight chips. In the clock synchronization process of at least two backlight chips, the above steps 202-206 may be performed multiple times, and each time the backlight chip can be used as the master backlight chip or the slave backlight chip.

[0053] The first counting duration and the second counting duration are used to determine the frequency of the clock signal of the master and slave backlight chips, respectively. Therefore, the first counting duration and the second counting duration can be determined with reference to the approximate frequency value of the master and slave backlight chips. The first counting duration and the second counting duration can be the same. If the master and slave backlight chips start counting and stop counting at the same time, the frequency error of the master and slave backlight chips can be directly determined based on the first counting value and the second counting value. The first counting duration and the second counting duration can also be different. The frequency of the backlight chip can be determined by the counting duration and the counting value, respectively, and then the frequency error of the master and slave backlight chips can be determined. In one embodiment, the first counting duration is equal to the second counting duration and is set to a fixed value, such as 1μs, 100ns, etc.

[0054] For the clock signal of the master backlight chip, the master backlight chip is counted within a first counting period, and the frequency of the clock signal of the master backlight chip is determined by the first counting value within the first counting period; similarly, the frequency of the clock signal of the slave backlight chip is determined by the second counting value of the slave backlight chip within a second counting period. Based on the frequency of the clock signal of the master backlight chip and the frequency of the clock signal of the slave backlight chip, the frequency error between the clock signal of the slave backlight chip and the clock signal of the master backlight chip is determined, thereby adjusting the frequency of the clock signal of the slave backlight chip.

[0055] It should be noted that the method for adjusting the frequency of the clock signal of the slave backlight chip is determined based on the circuit structure of the clock signal generating circuit of the slave backlight chip. The frequency error between the slave backlight chip and the main backlight chip gives the target frequency of the backlight chip. The parameters of the corresponding circuit in the slave backlight chip are adjusted based on the frequency error to achieve clock synchronization between the slave backlight chip and the main backlight chip.

[0056] In the method provided in the above embodiment, a first count value of the master backlight chip within a first count duration and a second count value of the slave backlight chip within a second count duration are obtained, and the first count value and the second count value are both obtained by cumulative counting based on the backlight chip's own clock source; the frequency error between the slave backlight chip and the master backlight chip is determined based on the first count value and the second count value; and the frequency of the slave backlight chip is adjusted based on the frequency error. The embodiment of the present application obtains the frequency error between the two backlight chips through the communication protocol between the backlight chips, and adjusts the frequency of the slave backlight chip based on the frequency error, thereby achieving precise clock synchronization between the master and slave devices, thereby improving the consistency and stability of the display effect.

[0057] In one embodiment, if Figure 3 The information interaction diagram shown in the figure obtains the first count value of the master backlight chip within the first count time length, and the second count value of the slave backlight chip within the second count time length, including:

[0058] The slave backlight chip receives a first command sent by the master backlight chip, and starts counting according to the first command;

[0059] After the second counting time, the slave backlight chip receives the second command sent by the master backlight chip and the first count value of the master backlight chip within the first counting time, stops counting according to the second command, and determines the second count value.

[0060] When performing clock synchronization, the master backlight chip triggers a first command and sends it to the slave backlight chip, and the slave backlight chip starts counting based on the first command; after a second counting period, the master backlight chip triggers a second command and sends it to the slave backlight chip, and the slave backlight chip stops counting based on the second command, and counts the second count value within the second counting period; and the master backlight chip autonomously completes the counting within the first counting period to obtain the first count value, and the first count value is sent by the master backlight chip to the slave backlight chip, and the slave backlight chip adjusts its own frequency according to the first count value, the first counting period, the second count value and the second counting period.

[0061] It should be noted that the counting and statistical process of the first counting value of the master backlight chip and the second counting value of the slave backlight chip do not affect each other, and the two can be performed at the same time or separately. Figure 4 In the information interaction process shown, the master backlight chip starts counting while sending the first command to the slave backlight chip; after receiving the first command, the slave backlight chip starts counting according to its own clock source; after the second counting time has passed, the master backlight chip stops counting, determines the first count value, and sends the second command and the first count value to the slave backlight chip; after receiving the second command, the slave backlight chip stops counting and determines the second count value. Figure 4In the process shown, the communication duration between the master and slave backlight chips is ignored, and the first counting duration is equal to the second counting duration.

[0062] In the method provided in the above embodiment, the main backlight chip triggers the command to control the slave backlight chip to complete the counting within the second counting time, thereby realizing clock synchronization between the slave backlight chip and the main backlight chip. This method only needs to send commands through a simple communication protocol, which simplifies the circuit design and reduces the cost.

[0063] In one embodiment, the first counting duration is equal to the second counting duration; accordingly, determining the frequency error between the slave backlight chip and the master backlight chip according to the first counting value and the second counting value includes:

[0064] Determining a count difference value according to the first count value and the second count value;

[0065] The frequency error between the slave backlight chip and the master backlight chip is determined according to the count difference and the first count value.

[0066] Wherein, the first counting duration is equal to the second counting duration, and the counting difference value represents the counting difference value between the master backlight chip and the slave backlight chip in the same time, and the ratio of the counting difference value to the first counting value is taken as the frequency error between the slave backlight chip and the master backlight chip. The frequency error is a percentage or decimal, which represents the error magnitude of the frequency of the clock signal of the slave backlight chip relative to the frequency of the clock signal of the master backlight chip.

[0067] In the method provided in the above embodiment, when the first counting duration is equal to the second counting duration, the frequency error is determined directly based on the first counting value and the second counting value. When there are multiple backlight chips, the same first preset duration is set, which can reduce the calculation amount of the chip and improve the efficiency of clock synchronization.

[0068] In one embodiment, if Figure 5 As shown, determining the frequency error between the slave backlight chip and the master backlight chip according to the first count value and the second count value includes:

[0069] Step 502, determining a first frequency of the main backlight chip according to the first counting value and the first counting duration;

[0070] Step 504, determining a second frequency of the slave backlight chip according to the second count value and the second count duration;

[0071] Step 506: Determine a frequency error between the slave backlight chip and the master backlight chip according to the first frequency and the second frequency.

[0072] When the first counting time length is not equal to the second counting time length, the first frequency of the master backlight chip and the second frequency of the slave backlight chip are calculated according to the counting time length and the counting value, so as to determine the frequency error between the slave backlight chip and the master backlight chip. Specifically, the difference between the first frequency and the second frequency can be directly used as the frequency error; the ratio of the difference between the first frequency and the second frequency to the first frequency can also be used as the frequency error.

[0073] In the method provided in the above embodiment, the first counting duration and the second counting duration are not limited. The slave backlight chip directly determines the first frequency of the master backlight chip based on the acquired data, and the counting process of the slave backlight chip will not affect the counting process of the master backlight chip.

[0074] In one embodiment, adjusting the frequency of the slave backlight chip based on the frequency error includes:

[0075] Based on the frequency error, circuit parameters of the phase-locked loop circuit of the slave backlight chip are adjusted to make the clock frequency of the slave backlight chip match the clock frequency of the master backlight chip.

[0076] Among them, the phase lock loop circuit (PLL circuit) is a circuit for generating a new signal synchronized with the input signal. The PLL circuit is a closed-loop negative feedback system, which can adjust the frequency of the output signal by adjusting the parameters of the feedback loop. In this embodiment, the backlight chip has a PLL circuit, and based on the frequency error, the circuit parameters of the feedback loop in the PLL circuit of the slave backlight chip are adjusted to match the clock frequency of the slave backlight chip with the clock frequency of the master backlight chip.

[0077] In the method provided in the above embodiment, accurate clock synchronization of the master and slave backlight chips is achieved by calculating the frequency error and adjusting the PLL circuit.

[0078] In one embodiment, the communication protocol adopted between the master backlight chip and the slave backlight chip is one or more combinations of the following communication protocols, wherein the following communication protocols include single-wire transmission protocol, SPI and I2C.

[0079] The above communication protocols are some of the more common inter-chip communication protocols. The two backlight chips can exchange information through simple and common communication protocols, which can simplify the circuit of the clock synchronization part and reduce the circuit cost.

[0080] In combination with the clock synchronization method of the backlight chip provided in the above embodiment, the present application further provides a backlight module, the backlight module includes at least two backlight units, each backlight unit includes a backlight chip;

[0081] The backlight chips of at least two backlight units are connected;

[0082] The slave backlight chip of the backlight chips of at least two backlight units adjusts the frequency of the slave backlight chip according to the first count value of the master backlight chip in the first count duration and the second count value of the slave backlight chip in the second count duration.

[0083] In one embodiment, after the master backlight chip starts counting, it sends a first command to the slave backlight chip, and the slave backlight chip starts counting based on the first command;

[0084] After the first counting time, the master backlight chip stops counting, determines a first count value, and sends the first count value and a second command to the slave backlight chip. The slave backlight chip stops counting based on the second command and determines a second count value.

[0085] In one embodiment, the first counting time length is equal to the second counting time length; the slave backlight chip adjusts the frequency of the slave backlight chip according to the first counting value and the second counting value.

[0086] In combination with the clock synchronization method of the backlight chip and the backlight module provided in the above embodiments, the embodiments of the present application also provide a display device; the display device includes a liquid crystal panel and a backlight module in any of the above embodiments; the backlight module executes the clock synchronization method of the backlight chip in any of the above embodiments.

Claims

1. A clock synchronization method for a backlight chip, characterized in that: The method is applied to control the clock signal synchronization of at least two backlight chips, and comprises: Acquire a first count value of the master backlight chip within a first count duration, and a second count value of the slave backlight chip within a second count duration, wherein the first count value and the second count value are both obtained by accumulating counts of the backlight chip based on its own clock source; Determine a frequency error between the slave backlight chip and the master backlight chip according to the first count value and the second count value; Based on the frequency error, the frequency of the slave backlight chip is adjusted.

2. The method according to claim 1, characterized in that The obtaining of a first count value of the master backlight chip within a first count duration, and a second count value of the slave backlight chip within a second count duration, comprises: The slave backlight chip receives a first command sent by the master backlight chip, and starts counting according to the first command; After the second counting time, the slave backlight chip receives the second command sent by the master backlight chip and the first counting value of the master backlight chip within the first counting time, stops counting according to the second command, and determines the second counting value.

3. The method according to claim 2, characterized in that The first counting duration is equal to the second counting duration; accordingly, determining the frequency error between the slave backlight chip and the master backlight chip according to the first counting value and the second counting value includes: Determine a count difference value according to the first count value and the second count value; A frequency error between the slave backlight chip and the master backlight chip is determined according to the count difference and the first count value.

4. The method according to claim 1, characterized in that: The determining the frequency error between the slave backlight chip and the master backlight chip according to the first count value and the second count value includes: Determining a first frequency of the main backlight chip according to the first counting value and the first counting duration; Determining a second frequency of the slave backlight chip according to the second count value and the second count duration; A frequency error between the slave backlight chip and the master backlight chip is determined according to the first frequency and the second frequency.

5. The method according to claim 1, characterized in that The adjusting the frequency of the slave backlight chip based on the frequency error includes: Based on the frequency error, the circuit parameters of the phase-locked loop circuit of the slave backlight chip are adjusted to make the clock frequency of the slave backlight chip match the clock frequency of the master backlight chip.

6. The method according to any one of claims 1 to 5, characterized in that: The communication protocol adopted between the master backlight chip and the slave backlight chip is one or more combinations of the following communication protocols, wherein the following communication protocols include single-wire transmission protocol, SPI and I2C.

7. A backlight module, characterized in that: The backlight module includes at least two backlight units, each of which includes a backlight chip; The backlight chips of the at least two backlight units are connected; A slave backlight chip among the backlight chips of the at least two backlight units adjusts the frequency of the slave backlight chip according to a first count value of the master backlight chip within a first count duration and a second count value of the slave backlight chip within a second count duration.

8. The backlight module according to claim 7, characterized in that: After the master backlight chip starts counting, the master backlight chip sends a first command to the slave backlight chip, and the slave backlight chip starts counting based on the first command; After the first counting time, the master backlight chip stops counting, determines the first counting value, and sends the first counting value and a second command to the slave backlight chip. The slave backlight chip stops counting and determines the second counting value based on the second command.

9. The backlight module according to claim 8, characterized in that: The first counting duration is equal to the second counting duration; and the slave backlight chip adjusts the frequency of the slave backlight chip according to the first counting value and the second counting value.

10. A display device, characterized in that: The display device comprises a liquid crystal panel and a backlight module as described in any one of claims 7 to 9; the backlight module executes a clock synchronization method for a backlight chip as described in any one of claims 1 to 6.

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