LED driving system and driving method

Abstract

The present invention discloses an LED drive system, comprising: a controller and a plurality of LED driver chips; the controller and the plurality of LED driver chips form a serial communication link, each of the LED driver chips being provided with a first data transmission port D1 and a second data transmission port D2; the LED drive system employs a bidirectional communication method for data transmission, the LED driver chip being provided with a second data transmission port control module, the second data transmission port control module determining whether to pull the second data transmission port to a low level state based on a drive status information characterization signal and a last chip identification signal. The present invention utilizes an idle output port on the last driver chip in the serial communication link to rapidly output abnormal drive status information on the communication link. This solves the defect in the prior art that the host computer cannot promptly process abnormal communication states.

Description

Technical Field

[0001] The present invention relates to the technical field of LED backlight technology, and in particular to an LED driving system and a driving method. Background Art

[0002] With the development of display technology, Mini-LED, OLED, and Micro-LED displays have gradually become the three main directions of display technology development, building on the foundation of traditional LCD displays. However, OLED display technology is limited by material properties, and pixel burn-in remains a difficult problem to solve. Micro-LED technology still needs to improve the efficiency of mass transfer technology to enable more cost-effective application in large-scale displays. Therefore, for the current situation, LCD displays using direct-lit Mini-LED backlight panels are the best display solution. Direct-lit Mini-LED backlight panels are composed of a high-density LED array made of even finer Mini-LED beads (with dimensions reduced to less than 100 microns). The entire backlight panel can be divided into multiple backlight zones, with the number of LEDs in each zone increasing from tens of traditional LEDs to hundreds or even thousands. Therefore, how to drive and control these numerous Mini-LED beads so that their brightness matches the display of the LCD panel becomes a core issue in Mini-LED backlight panel applications.

[0003] like Figure 1 As shown in the figure, in a conventional single-wire bus LED driver system, the LED driver chip has only one input port, Din, and one output port, Dout. The chips are serially connected via the Din / Dout ports, with the output port Dout of the preceding chip connected to the input port Din of the following chip. The host computer (HOST) inputs a signal to the input port Din of the first chip, and then transmits the data serially to subsequent chips.

[0004] In the aforementioned communication link, each LED driver chip generates driver status information, such as fault information (such as LED driver pin open, LED driver pin short, LED driver pin overvoltage / undervoltage), which is transmitted to the host computer via the serial communication link. The host computer then performs system processing on the corresponding LED driver chip based on the received error information. For example, if an LED pin short occurs, the corresponding chip is shut down. If an LED pin is undervoltage, the DC-DC output voltage is increased.

[0005] However, when there are too many LED driver chips connected in series in the LED driver system, or the host computer HOST communication frequency is too slow, the driver status information cannot be responded to and processed in a timely manner.

[0006] It can be seen from this that a new LED driving system and driving method are needed in the prior art to enable the host computer to respond promptly to abnormal states of the LED driving chip. Summary of the Invention

[0007] The technical purpose of the present invention is to provide an LED driving system and driving method. The technical purpose of the present invention is to use the output port of the last LED driver chip to quickly obtain the driving abnormal state occurring on the communication link in a two-way communication mode, and enable the host computer to process it in time.

[0008] Based on the above technical objectives, the present invention provides an LED driving system, the LED driving system comprising:

[0009] Controller and multiple LED driver chips;

[0010] The controller and the plurality of LED driver chips form a serial communication link, and the controller acts as a host to send instruction data to the plurality of LED driver chips as slaves;

[0011] Each of the LED driver chips is provided with a first data transmission port D1 and a second data transmission port D2; the LED driver system adopts a bidirectional communication method for data transmission. When the LED driver chip is powered on, the first data transmission port D1 is set to a data receiving state, and the second data transmission port D2 is set to a data sending state. When the first data transmission port of the LED driver chip completes receiving a data frame, it switches to a data sending state, and when the second data transmission port D2 completes sending a data frame, it switches to a data receiving state.

[0012] The LED driver chip is provided with a second data transmission port control module, which determines whether to pull the second data transmission port to a low level state according to the driving state information characterization signal and the last chip identification signal.

[0013] In one embodiment, the second data transmission port of the last LED driver chip in the serial communication link is connected to a high-level driving power supply via a resistor.

[0014] In one embodiment, the status information representative signal is driving status information written by the LED driver chip and contained in a data frame transmitted in the serial communication link.

[0015] In one embodiment, the last chip identification signal is identification information used by the LED driver chip to determine whether it is the last driver chip based on frame header count information contained in the data frame and total number of LED driver chips in the serial communication link.

[0016] In one embodiment, when the status information representation signal is at a high level, it indicates that the data frame contains driving status information indicating that the LED driver chip is in an abnormal state; when the status information representation signal is at a low level, it indicates that the data frame does not contain driving status information indicating that the LED driver chip is in an abnormal state.

[0017] In one embodiment, when the last chip identification signal is at a high level, it indicates that the current LED driver chip is the last LED driver chip; when the last chip identification signal is at a low level, it indicates that the current LED driver chip is not the last LED driver chip.

[0018] In one embodiment, the second data transmission port control module includes a switch tube and an AND operation unit, and the AND operation unit generates a control signal for controlling the switch tube to turn on according to the input state information characterization signal and the last chip identification signal.

[0019] In one embodiment, each of the LED driver chips has a plurality of LED driver channel pins, and the LED driver channel pins are used to connect to an LED light string to directly control the light emission of the LED light string.

[0020] The present invention further provides an LED driving system, comprising:

[0021] A controller and multiple LED driver chip serial units, each of which includes an LED driver chip; the controller HOST and each of the LED driver chip serial units form a serial communication link, with the controller acting as a host to send command data to the multiple LED driver chips acting as slaves;

[0022] Each of the LED driver chips is provided with a first data transmission port D1 and a second data transmission port D2; the LED driver system adopts a bidirectional communication method for data transmission. When the LED driver chip is powered on, the first data transmission port D1 is set to a data receiving state, and the second data transmission port D2 is set to a data sending state. When the first data transmission port of the LED driver chip completes receiving a data frame, it switches to a data sending state, and when the second data transmission port D2 completes sending a data frame, it switches to a data receiving state.

[0023] The LED driver chip is provided with a second data transmission port control module, which determines whether to pull the second data transmission port to a low level state according to the driving state information characterization signal and the last chip identification signal.

[0024] Compared with the prior art, one or more embodiments of the present invention may have the following advantages:

[0025] The present invention utilizes the idle output port on the last driver chip in the serial communication link to quickly output abnormal drive status information on the communication link, thereby resolving the defect in the prior art that the host computer cannot handle abnormal communication status in a timely manner.

[0026] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the structures particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0028] Figure 1 It is a schematic diagram of the structure of the LED driving system in the prior art;

[0029] Figure 2 1 is a schematic structural diagram of an LED driving system according to a first embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the data frame structure used by the LED driving system of the present invention;

[0031] Figure 4 is a structural diagram of a second data transmission port control module according to the first embodiment of the present invention;

[0032] Figure 5 FIG. 1 is a structural diagram of an LED driving system according to a second embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings.

[0034] It should be understood that when an element or layer is referred to as being "on," "adjacent to," "connected to," or "coupled to" another element or layer, it can be directly on, adjacent to, connected to, or coupled to the other element or layer, or there can be intervening elements or layers. Conversely, when an element is referred to as being "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" another element or layer, there can be no intervening elements or layers. It should be understood that while the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, layers, and / or parts should not be limited by these terms. These terms are merely used to distinguish one element, component, region, layer, or part from another. Thus, without departing from the teachings of the present invention, a first element, component, region, layer, or part discussed below may be represented as a second element, component, region, layer, or part. Furthermore, when a second element, component, region, layer, or part is discussed, it does not necessarily mean that the first element, component, region, layer, or part is present in the present invention.

[0035] Spatially relative terms such as "under," "beneath," "below," "under," "above," "above," etc., may be used herein for convenience of description to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that in addition to the orientations shown in the figures, the spatially relative terms are intended to include different orientations of the device in use and operation. For example, if the device in the drawings is flipped, then the elements or features described as "under the other elements" or "under it" or "under it" will be oriented as "on" the other elements or features. Thus, the exemplary terms "under" and "under" may include both upper and lower orientations. The device may be oriented otherwise (rotated 90 degrees or in other orientations) and the spatial descriptors used herein are interpreted accordingly.

[0036] The purpose of the terms used herein is only to describe specific embodiments and is not intended to limit the present invention. When used herein, the singular forms "a", "an", and "the" are intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "comprising" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0037] Example 1

[0038] like Figure 2The LED driving system of the present invention shown in the figure includes: a controller HOST and multiple LED driving chips Chip1~Chip4; the controller HOST and the multiple LED driving chips Chip1~Chip4 form a serial communication link, and the controller acts as a host to send command data to the multiple LED driving chips Chip1~Chip4 as slaves.

[0039] Each of the LED driver chips has a plurality of LED driver channel pins LED1 to LED4 , and the LED driver channel pins are used to connect to an LED light string to directly control the light emission of the LED light string.

[0040] Each LED driver chip is provided with a first data transmission port D1 and a second data transmission port D2. The serial communication link means that the first data transmission port D1 of each LED driver chip is connected to the second data transmission port D2 of the LED driver chip in the previous stage, and the second data transmission port D2 of each LED driver chip is connected to the first data transmission port D1 of the LED driver chip in the next stage. The first LED driver chip in the serial communication link is connected to the transmission port TX / RX of the controller HOST.

[0041] In this example, the LED driver system uses a bidirectional communication method for data transmission. That is, when the LED driver chip is powered on, the first data transmission port D1 is set to a data receiving state, while the second data transmission port D2 is set to a data transmitting state. When the first data transmission port of the LED driver chip completes receiving a data frame, it switches to a data transmitting state. When the second data transmission port D2 completes sending a data frame, it switches to a data receiving state.

[0042] In the present invention, the structure of the data frame is as follows Figure 3 As shown in FIG, the data frame includes a frame header bit (Start_Bits), a control command bit (Command), a register address bit (Reg_Addr), an echo data bit (Echo), a data packet length bit (Data_Len), and a backlight brightness data bit (DATA). The order of the control command bit (Command), register address bit (Reg_Addr), echo data bit (Echo), and data packet length bit (Data_Len) can be switched at will.

[0043] The data frame header bits (Start_Bits) are used to identify the physical sequence position of the driver chip currently receiving the data frame on the serial communication link. The data format of the initial data frame header bits (Start_Bits) sent by the controller HOST is in the form of "Bit S + Bit 1". When each LED driver chip receives the data frame header bit, it automatically adds a data bit to the header bit, so the header bit becomes "Bit S + Bit 0 + Bit 1". The "Bit 0" represents that the driver chip Chip1 is the first in the physical sequence position on the serial communication link. Accordingly, when the driver chip Chip1 identifies its own sequence position through the header bit, it collects the first brightness data packet in the subsequent backlight brightness data bits as the backlight brightness data required for its own brightness driving display.

[0044] Similarly, the frame header bits received by the first input terminal of driver chip Chip2 are "Bit S + Bit 0 + Bit 1". Driver chip Chip2 adds a data bit to the header bits, changing the frame header bits to "Bit S + Bit 0 + Bit 0 + Bit 1". The two "Bit 0s" represent that driver chip Chip2 is the second in the physical sequence position on the serial communication link. Correspondingly, after driver chip Chip2 identifies its own sequence position through the frame header bits, it collects the second brightness data packet in the subsequent backlight brightness data bits as the backlight brightness data needed for brightness driving and display. This process is repeated until all n driver chips obtain the corresponding brightness data packets in the backlight brightness data bits as the backlight brightness data needed for brightness driving and display.

[0045] The data in the brightness data packet is the voltage and current information for driving the LED light string when DC dimming is used, and is the pulse modulation frequency information for driving the LED switch, such as the PWM duty cycle, when PWM dimming is used.

[0046] At the same time, the data frame also includes information recording the number of LED driver chips in the entire serial communication link. For example, this information can be set in the control command bit.

[0047] In this embodiment, the data frame also transmits drive status information written into the data frame by each LED driver chip, such as LED driver pin open (LED pin open), LED driver pin short (LED pin short), and LED driver pin overvoltage / undervoltage information. This drive status information is written into the control command bit by the LED driver chip. Specifically, when an LED driver chip experiences an abnormal LED state as indicated by the aforementioned drive status information, the LED driver chip proactively writes the corresponding drive status information into the data frame, overwriting any drive status information already written by other preceding LED driver chips in the data frame. If the LED driver chip does not experience an abnormal LED state as indicated by the aforementioned drive status information, no drive status information is written into the data frame.

[0048] According to the aforementioned serial communication link, the second data transmission port D2 of the last LED driver chip in this embodiment is unused. Furthermore, since this embodiment utilizes bidirectional communication for data transmission, after a data frame is transmitted to the last LED driver chip, the driving status information contained within the data frame must be inverted and then transmitted to the controller HOST via the bidirectional communication mode. However, if there are a large number of LED driver chips in the serial communication link, or if the controller HOST processes data at a low frequency, or if the controller HOST cannot provide a sufficient time window to receive reversely transmitted data due to data transmission frequency requirements, the driving status information in the data frame may not be promptly captured by the controller and processed accordingly.

[0049] Therefore, in this embodiment, Figure 4 As shown, the LED driver chip is provided with a second data transmission port control module, which includes a switch tube, namely an AND gate. The gate control terminal of the switch tube is connected to the output terminal of the AND gate. One input terminal of the AND gate inputs a drive status information characterization signal. If the drive status information exists in the data frame, it is a high-level signal, otherwise it is a low-level signal. The other input terminal is a signal identifying that the current LED driver chip is the last chip. If the current LED driver chip is the last chip, it is a high-level 1, otherwise it is a low-level 0. The source and drain of the switch tube, one of which is grounded, and the other is connected to the second data transmission port inside the LED driver chip. Therefore, when the LED driver chip is simultaneously satisfied with judging itself as the last LED driver chip and there is drive status information in the data frame, the second data transmission port of the last LED driver chip will be pulled to a low level. When the second data transmission port of the last LED driver chip is externally connected to a high-level V CC When the second data transmission port is pulled down to a low level state, it will be detected immediately. Thus, the controller HOST can quickly obtain the driving state information in the data frame.

[0050] In this embodiment, since pulling the two data transmission ports to a low level can only express one type of driving state information, the last LED driver chip is required to filter and process the driving state information in the data frame. For example, only the undervoltage state information in the data frame is processed. When the undervoltage state information is written into the data frame, the driving state information representative signal input to the second data transmission port control module is a high-level signal.

[0051] Example 2

[0052] like Figure 5 The LED driving system of the present embodiment shown in the figure includes: a controller HOST and multiple LED driver chip serial units, each of which includes LED driver chips Chip1 to Chip4; the controller HOST and each of the LED driver chip serial units form a serial communication link, and the controller acts as a host to send command data to the multiple LED driver chips Chip1 to Chip4 acting as slaves.

[0053] Each of the LED driver chips has a plurality of LED driver channel pins LED1 to LED4 , and the LED driver channel pins are used to connect to an LED light string to directly control the light emission of the LED light string.

[0054] Each LED driver chip is provided with a first data transmission port D1 and a second data transmission port D2. The serial communication link means that the first data transmission port D1 of each LED driver chip is connected to the second data transmission port D2 of the LED driver chip in the previous stage, and the second data transmission port D2 of each LED driver chip is connected to the first data transmission port D1 of the LED driver chip in the next stage. The first LED driver chip in the LED driver chip serial unit is connected to the transmission port TX / RX of the controller HOST.

[0055] Similarly, in this embodiment, the LED driver system uses a bidirectional communication method for data transmission. That is, when the LED driver chip is powered on, the first data transmission port D1 is set to a data receiving state, and the second data transmission port D2 is set to a data transmitting state. When the first data transmission port of the LED driver chip completes receiving a data frame, it switches to a data transmitting state. When the second data transmission port D2 completes sending a data frame, it switches to a data receiving state.

[0056] The data frame format used in this embodiment and the second data transmission port control module provided in the LED driver chip are consistent with those in the aforementioned embodiment 1.

[0057] The present invention may be a system, method and / or computer program product at any possible level of integrated technical detail. The computer program product may include a computer-readable storage medium (or multiple media) having computer-readable program instructions thereon for causing a processor to perform various aspects of the present invention.

[0058] A computer-readable storage medium can be a tangible device that can retain and store instructions used by an instruction execution device. The computer-readable storage medium can be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of computer-readable storage media includes the following: a portable computer floppy disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), a memory stick, a floppy disk, a mechanical encoding device such as a punch card or raised structure in grooves having instructions recorded thereon, and any suitable combination of the foregoing. A computer-readable storage medium, as used herein, should not be construed as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted by a wire.

[0059] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to a corresponding computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions to be stored in a computer-readable storage medium within the corresponding computing / processing device.

[0060] The computer-readable program instructions for performing the operation of the present invention can be assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, configuration data for integrated circuits, or source code or object code written in any combination of one or more programming languages and procedural programming languages. The computer-readable program instructions can be executed entirely on the user's computer, partly on the user's computer, as an independent software package, partly on the user's computer, partly on a remote computer or entirely on a remote computer or server. In the latter case, the remote computer can be connected to the user's computer by any type of network including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (for example, by using the Internet of an Internet service provider). In certain embodiments, the electronic circuit including, for example, a programmable logic circuit, a field programmable gate array (FPGA) or a programmable logic array (PLA) can execute the computer-readable program instructions by utilizing the state information of the computer-readable program instructions to personalize the electronic circuit, thereby performing various aspects of the present invention.

[0061] Various aspects of the present invention are described herein with reference to flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0062] These computer-readable program instructions may be provided to a processor of a computer or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device create instructions for implementing the flowcharts and / or block diagrams. Figure 1 These computer-readable program instructions may also be stored in a computer-readable storage medium capable of booting a computer, a programmable data processing device and / or other device to operate in a specific manner, such that the computer-readable storage medium having the instructions stored therein comprises an article of manufacture that includes the instructions for implementing aspects of the functions / actions specified in the flowchart and / or block diagram blocks.

[0063] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other apparatus to cause a series of operational steps to be performed on the computer, other programmable device, or other apparatus for producing a computer-implemented process, such that the instructions executed on the computer, other programmable device, or other apparatus implement the functions / actions specified in the flowchart and / or block diagram blocks.

[0064] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, segment, or portion of instructions, which includes one or more executable instructions for implementing the specified logical function. In some alternative implementations, the functions indicated in the blocks may occur out of the order indicated in the diagrams. For example, two blocks shown in succession may, in practice, be completed as a single step, executed concurrently, substantially concurrently, with partial or full temporal overlap, or the blocks may sometimes be executed in reverse order, depending on the functions involved. It will also be noted that each block of the block diagram and / or flowchart illustration, as well as combinations of blocks in the block diagram and / or flowchart illustration, may be implemented by a dedicated hardware-based system that performs the specified functions or actions or executes a combination of dedicated hardware and computer instructions.

[0065] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, apparatuses (devices) and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0066] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0067] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

Claims

1. An LED driving system, comprising: Controller and multiple LED driver chips; The controller and the plurality of LED driver chips form a serial communication link, and the controller acts as a host to send instruction data to the plurality of LED driver chips as slaves; characterized in that: Each of the LED driver chips is provided with a first data transmission port D1 and a second data transmission port D2; the LED driver system adopts a bidirectional communication method for data transmission. When the LED driver chip is powered on, the first data transmission port D1 is set to a data receiving state, and the second data transmission port D2 is set to a data sending state. When the first data transmission port of the LED driver chip completes receiving a data frame, it switches to a data sending state, and when the second data transmission port D2 completes sending a data frame, it switches to a data receiving state. The LED driver chip is provided with a second data transmission port control module, which determines whether to pull the second data transmission port to a low level state according to the driving state information representation signal and the last chip identification signal; and when the LED driver chip is satisfied with the determination that it is the last LED driver chip and the driving state information representation signal is present in the data frame, the second data transmission port of the last LED driver chip will be pulled to a low level; The driving state information representative signal is the driving state information written by the LED driving chip and contained in the data frame transmitted in the serial communication link; The last chip identification signal is identification information used by the LED driver chip to determine whether it is the last driver chip based on the frame header count information contained in the data frame and the total number of LED driver chips in the serial communication link.

2. The LED driving system according to claim 1, wherein: The second data transmission port of the last LED driver chip in the serial communication link is connected to a high-level driving power supply via a resistor.

3. The LED driving system according to claim 1, wherein: The second data transmission port control module includes a switch tube and an AND operation unit. The AND operation unit generates a control signal for controlling the switch tube to turn on according to the input state information characterization signal and the last chip identification signal.

4. The LED driving system according to claim 1, wherein: Each of the LED driver chips has a plurality of LED driver channel pins, and the LED driver channel pins are used to connect to an LED light string to directly control the light emission of the LED light string.

5. The LED driving system according to claim 3, wherein: The driving status information includes an LED driving pin open circuit state, an LED driving pin short circuit state, or an LED driving pin overvoltage / undervoltage state.

6. An LED driving system, characterized in that: The LED driving system includes: A controller and multiple LED driver chip serial units, each LED driver chip serial unit including an LED driver chip; the controller and each LED driver chip serial unit form a serial communication link, with the controller acting as a host to send command data to the multiple LED driver chips acting as slaves; Each of the LED driver chips is provided with a first data transmission port D1 and a second data transmission port D2; the LED driver system adopts a bidirectional communication method for data transmission. When the LED driver chip is powered on, the first data transmission port D1 is set to a data receiving state, and the second data transmission port D2 is set to a data sending state. When the first data transmission port of the LED driver chip completes receiving a data frame, it switches to a data sending state, and when the second data transmission port D2 completes sending a data frame, it switches to a data receiving state. The LED driver chip is provided with a second data transmission port control module, which determines whether to pull the second data transmission port to a low level state according to the driving state information representation signal and the last chip identification signal; and when the LED driver chip is satisfied with the determination that it is the last LED driver chip and the driving state information representation signal is present in the data frame, the second data transmission port of the last LED driver chip will be pulled to a low level; The driving state information representative signal is the driving state information written by the LED driving chip and contained in the data frame transmitted in the serial communication link; The last chip identification signal is identification information used by the LED driver chip to determine whether it is the last driver chip based on the frame header count information contained in the data frame and the total number of LED driver chips in the serial communication link.

7. An LED backlight panel, comprising a plurality of LED driving units and a plurality of LED light groups, wherein the LED driving units are constructed using the LED driving system according to any one of claims 1 to 6.

8. An LED display device comprising the backlight panel according to claim 7.

Images