Vehicle-mounted micro-led partition driving control system and control method thereof

Abstract

The application relates to the technical field of vehicle lamps, in particular to a vehicle-mounted Micro-LED partition driving control system and a control method thereof, which comprises an ASIC control chip and a driving substrate; the driving substrate comprises a plurality of pixel driving modules arranged in an array; each pixel driving module comprises a driving unit and a Micro-LED; the pixel driving modules are divided into M driving partitions; each driving partition is provided with a corresponding data interface and a power input end; each driving partition is connected with the ASIC control chip through the corresponding data interface; and each driving partition is connected with a power supply through the corresponding power input end; the ASIC control chip can split an original video frame into sub-picture data packets belonging to each driving partition and output the sub-picture data packets to each driving partition for display. The application is suitable for the design of a vehicle-mounted Micro-LED scene with super-high pixels, effectively breaks through the data bandwidth bottleneck, forcibly disperses the limit driving current, solves the voltage drop problem on a large-area silicon substrate, and can meet the vehicle-grade safety requirements.

Description

Technical Field

[0001] This invention relates to the field of automotive lighting technology, and in particular to an on-board Micro-LED zone drive control system and its control method. Background Technology

[0002] With the development of intelligent connected vehicles, high-resolution adaptive high beam (ADB) and road projection functions (such as cornering light carpets, navigation arrows, and anti-glare shielding) place higher demands on vehicle headlight pixels. Automotive Micro-LED integrated lighting and projection technology has become the industry mainstream. Currently, to achieve high-precision light pattern control, the pixel pitch of Micro-LED arrays is typically reduced to around 40 pixels, and the total number of pixels is evolving from the traditional 10,000 to 20,000 pixel level to even higher pixel levels.

[0003] To drive these ultra-high density Micro-LED arrays, a packaging method is typically used that integrates the LED light-emitting array with the silicon-based driver chip through wafer-level flip-chip bonding (C2W or D2W), and an external ASIC provides video frame data and control signals.

[0004] Existing high-pixel Micro-LED automotive lighting architectures (such as products with a total pixel count of 16,000 to 25,000) typically employ a design of "centralized power supply and shared serial data with few channels" in their internal topology. For example... Figure 1 As shown, the driver chip internally receives data from the ASIC via 1 to 4 SPI or QSPI buses, and distributes the data to each pixel unit internally through a daisy chain or global bus. Simultaneously, the pixel power supply terminal (VDDP) of the driver chip is globally connected on the physical traces, meaning the entire LED array of over 20,000 pixels shares the same VDDP power network. When the pixel size is further reduced to the ultra-high pixel level of 40 mesh spacing and a total pixel count exceeding 25,000, the existing architecture faces the following serious technical bottlenecks: 1. Severe data bandwidth congestion leads to image latency: Several pixels at 8-bit grayscale (PWM resolution) and a 420Hz refresh rate generate a huge data throughput. Existing single-channel or multi-channel QSPI interfaces cannot meet the requirements of high frame rate (such as 60FPS) real-time road projection, easily resulting in image tearing or latency.

[0005] 2. A dramatic increase in IRDrop leads to uneven light emission (mura) and thermal failure: When several pixels are fully powered on, the instantaneous theoretical total current reaches as high as 120A. Using a centralized VDDP power supply will generate a severe IRDrop on a large area of ​​the silicon substrate, resulting in a huge difference in the forward voltage (VF) of the pixels between the central and edge areas of the chip, causing severe brightness unevenness. Simultaneously, the 120A current concentrated on a few pins and traces will lead to a dramatic increase in local heat flux density, easily causing micro-bump thermal stress cracking and reducing bonding yield.

[0006] 3. Extremely low fault tolerance, unable to meet automotive-grade safety mechanisms: Under the global shared architecture, once a local power network short circuit occurs, the entire headlight will "go black," failing to meet the "Limp Home" safety requirements in automotive-grade AEC-Q100. Summary of the Invention

[0007] The technical problem this invention aims to solve is: to address the issues of severe data bandwidth congestion leading to image delay, increased IRD drop, uneven light emission, thermal failure, and extremely low fault tolerance in existing Micro-LED automotive lighting architectures when facing ultra-high pixel counts, thus failing to meet automotive-grade safety requirements. This invention provides an automotive Micro-LED zoned drive control system suitable for ultra-high pixel automotive Micro-LED scenarios. It effectively overcomes the data bandwidth bottleneck and forcibly disperses the extreme drive current, fundamentally solving the voltage drop problem on large-area silicon substrates and meeting automotive-grade safety requirements.

[0008] The technical solution adopted by this invention to solve its technical problem is: an in-vehicle Micro-LED zone drive control system, the system comprising: ASIC control chip; A driving substrate, wherein the driving substrate includes a plurality of pixel driving modules arranged in an array, the number of the pixel driving modules being N, and each pixel driving module including a driving unit and a Micro-LED electrically connected; The pixel driving modules are divided into M driving partitions. Each driving partition is equipped with a corresponding data interface and a power input terminal. Each driving partition is connected to the ASIC control chip through the corresponding data interface and to the power supply through the corresponding power input terminal. The ASIC control chip can split the original video frame into sub-screen data packets belonging to each driving partition, and output them to each driving partition for display.

[0009] Furthermore, specifically, the pixel driving modules are divided according to the number of pixel driving modules, and the number of driving partitions M is one step.

[0010] Furthermore, specifically, the number of pixel driving modules N ≥ 2.5W, and the number of pixel driving modules in each driving partition is... indivual.

[0011] Furthermore, specifically, each driving unit corresponds one-to-one with a Micro-LED, and the driving unit is electrically connected to the corresponding Micro-LED.

[0012] Furthermore, specifically, the data interface is a QSPI interface.

[0013] Furthermore, specifically, each of the power input terminals is physically isolated from each other within the drive substrate.

[0014] A method for controlling the zoned drive of a vehicle-mounted Micro-LED, the method employing the vehicle-mounted Micro-LED zoned drive control system described above, the method comprising the following steps: S1, divide all the pixel driving modules on the driving substrate into M driving partitions; S2, the ASIC control chip acquires the original video frame, performs thermal derating mask superposition and Gamma correction on the original video frame, and cuts and divides the corrected original video frame to obtain M sub-picture data packets. Each sub-screen data packet corresponds to a driver partition; S3, the ASIC control chip transmits sub-screen data packets in parallel to the corresponding driver partitions through the data interface; S4, each of the drive partitions receives and caches the sub-screen data packets; S5, the ASIC control chip confirms whether all M sub-screen data packets have been transmitted. If so, it sends a global latch signal to each of the driving partitions. The driving partitions synchronously flip the SRAM read / write pointers based on the global latch signal in the same clock cycle and convert the digital grayscale value into a PWM signal through the internal PWM generator. S6, the PWM signal is input to the driving unit of each pixel driving module, and the driving unit controls the Micro-LED based on the PWM signal.

[0015] Furthermore, specifically, in step S6, the driving unit obtains driving current from the corresponding power input terminal to light up the corresponding Micro-LED.

[0016] Furthermore, specifically, the sub-screen data packet includes a header, The grayscale data of each pixel and the CRC check code are received. Each of the driving partitions will also perform CRC verification based on the CRC check code when receiving the sub-screen data packet.

[0017] Furthermore, specifically, each of the aforementioned driving regions employs a double-buffering mechanism to acquire the sub-screen data packets.

[0018] The beneficial effects of this invention are: 1. The vehicle-mounted Micro-LED partition drive control system of the present invention can split the original video frame into sub-screen data packets belonging to each drive partition through the ASIC control chip, and output them to each drive partition for display. This effectively breaks through the data bandwidth bottleneck, achieves extremely low latency, improves display efficiency, and avoids the huge computational redundancy brought about by traditional global centralized processing, significantly reducing the dynamic power consumption of the main control chip in the data throughput process. 2. By distributing the total power supply to each power input terminal, the physical power supply path from the power supply to the center of the array is shortened. This completely solves the voltage drop problem on large-area silicon substrates, ensures the consistency of the forward voltage (VF) of all pixels, strictly controls the matrix brightness deviation within ±1%, and avoids local heat accumulation, thus improving bonding reliability.

[0019] 3. Each drive partition is connected to the ASIC control chip via a corresponding data interface and to a power source via a corresponding power input terminal. However, if the data line of any drive partition breaks or the power supply is short-circuited, only the pixels of that drive partition will be extinguished. The system can still reconstruct the safety light pattern using the remaining 19 drive partitions, greatly improving nighttime driving safety and meeting automotive-grade safety requirements. Furthermore, this independent partition architecture allows the system to directly physically shut down or put non-working partitions into sleep mode in specific lighting scenarios (such as adaptive high-beam shading scenarios where only partial illumination is required), avoiding low-current leakage losses caused by global power supply and achieving more refined regional energy management. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Figure 1 This is a schematic diagram of the prior art of this invention.

[0022] Figure 2 This is a schematic diagram of the system structure of Embodiment 1 of the present invention.

[0023] Figure 3 This is a schematic diagram of the driver partition structure according to Embodiment 1 of the present invention.

[0024] Figure 4 This is a schematic diagram of the pixel driving module according to Embodiment 1 of the present invention.

[0025] Figure 5 This is a schematic diagram of the method flow of Embodiment 2 of the present invention.

[0026] In the diagram: 1. ASIC control chip; 2. Driver substrate; 3. Pixel driver module; 4. Driver partition; 31. Driver unit; 32. Micro-LED; 41. Data interface; 42. Power input terminal. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0028] Example 1: This invention provides an in-vehicle Micro-LED zone drive control system, such as... Figure 2-4 As shown, the system includes: ASIC control chip 1 and drive substrate 2, with ASIC control chip 1 and drive substrate 2 electrically connected.

[0029] The driving substrate 2 includes a plurality of pixel driving modules 3 arranged in an array, the number of which is N. Each pixel driving module 3 includes a driving unit 31 and a Micro-LED 32 electrically connected. All pixel driving modules 3 are divided into M driving partitions 4. Each driving partition 4 is provided with a corresponding data interface 41 and a power input terminal 42. Each driving partition 4 is connected to the ASIC control chip 1 through the corresponding data interface 41 and to a power supply through the corresponding power input terminal 42. The ASIC control chip 1 can split the original video frame into sub-picture data packets belonging to each driving partition 4 and output them to each driving partition 4 for display, effectively breaking through the data bandwidth bottleneck, achieving extremely low latency, and improving display efficiency.

[0030] Furthermore, to address the voltage drop (IR Drop) issue on large-area silicon substrates, this embodiment improves the physical structure of the power distribution network (PDN). Specifically, the main power output from the main power circuit (e.g., using a mature dual-channel high-power DC / DC controller) is forcibly distributed into 20 independent power supply branches through a star topology routing structure, each connected to a power input terminal 42, and then supplying power to the corresponding drive partition 4 through the power input terminal 42. This physical splitting significantly shortens the physical power supply path from the power supply to the array center, ensuring the consistency of the forward voltage VF of all pixels, strictly controlling the matrix brightness deviation within ±12.5%, and avoiding heat accumulation caused by local large currents, thus improving bonding reliability. In addition, each drive partition 4 is connected to the ASIC control chip 1 through a corresponding data interface 41 and connected to an independent power supply branch through a corresponding power input terminal 42. If any one of the drive partitions 4 experiences a data cable breakage or power short circuit, causing only the pixels of that drive partition 4 to go out, the system can still use the remaining 19 drive partitions 4 to reconstruct the safety light pattern, greatly improving the fault tolerance and safety of night driving and meeting strict automotive-grade safety requirements.

[0031] Specifically, the number of pixel driver modules 3, N ≥ 2.5W, and the number of pixel driver modules 3 in each driver partition 4 is... The number of pixel driving modules 3 is divided into driving partitions 4, with M being the number of driving partitions 4. For example, if the number of pixel driving modules 3 N=51200, the pixel driving modules 3 are arranged in a 400 substrate module array on the driving substrate 2. When M=20, the number of pixel driving modules 3 in each driving partition 4 is 2560.

[0032] It should be noted that in this embodiment, the number of drive partitions 4 is the same as the number of power input terminals 42 and the number of data interfaces 41.

[0033] In this embodiment, each driving unit 31 corresponds one-to-one with a Micro-LED 32, and the driving units 31 are electrically connected to their respective Micro-LED 32. In other words, one driving unit 31 controls one Micro-LED 32, achieving independent active driving of a single Micro-LED 32. Furthermore, the driving unit 31 includes a constant current source switch to avoid the problem of severe local brightness unevenness caused by the slight internal resistance differences between the individual Micro-LED 32 chips. In this embodiment, the data interface 41 is a QSPI interface. The ASIC control chip 1 is connected to the QSPI interface through the QSPI bus to improve the accuracy and effectiveness of data packet transmission for each sub-screen, and can meet the high-frequency real-time road projection requirements of N pixel driving modules 3 at 8-bit grayscale, 420Hz refresh rate and 60FPS.

[0034] In this embodiment, each power input terminal 42 is physically isolated from each other inside the driving substrate 2, fundamentally solving the problem of thermoelectric accumulation at the microscale. When all N pixel driving modules 3 are fully operational, the instantaneous theoretical total current reaches as high as 120A. If a centralized power supply is used, the 120A current concentrated on the driving substrate 2, which is only a few square millimeters in size, will produce an extremely severe voltage drop, resulting in a huge difference in the positive voltage VF between the center and edge pixels of the chip, leading to uneven brightness. At the same time, the extremely high heat flux density can easily cause thermal stress cracking of the micro-bumps.

[0035] Example 2: This application provides an embodiment of an in-vehicle Micro-LED zone drive control method, which employs the aforementioned in-vehicle Micro-LED zone drive control system. Figure 5 As shown, the method includes the following steps: S1, divide all pixel driving modules 3 on the driving substrate 2 into M driving partitions 4.

[0036] S2, ASIC control chip 1 acquires the original video frame, performs thermal derating mask overlay and Gamma correction on the original video frame, and cuts and divides the corrected original video frame to obtain M sub-picture data packets; wherein, each sub-picture data packet corresponds to a driving partition 4.

[0037] Furthermore, the thermal downscaling mask overlay and gamma correction of the original video frames specifically include: The storage uses a spatial weight matrix that matches the pixel array resolution (e.g., a 400-pixel array). Specifically, the spatial weight matrix that matches the pixel array resolution is set based on the chip's physical heat dissipation model and exhibits a distribution characteristic that increases from the center to the edge.

[0038] The system performs pixel-by-pixel multiplication of the grayscale values ​​of each pixel in the original video frame with the weight values ​​of the corresponding coordinates in the spatial weight matrix that matches the resolution of the pixel array to generate intermediate image data. Through this superposition process, the system actively reduces the maximum allowable grayscale value of pixels in the heat dissipation bottleneck area (central area) at the software data level, reduces unnecessary peak power output at the data source, avoids ineffective power consumption and thermal decay caused by high brightness, and ensures that Micro-LED always maintains extremely high electro-optical conversion efficiency. This limits the maximum driving current and luminous power of the corresponding Micro-LED, realizes feedforward spatial thermal derating, and effectively avoids the risk of micro-bump melting or chip thermal stress cracking caused by local overheating.

[0039] The built-in Gamma correction algorithm or lookup table (LUT) is invoked to perform nonlinear mapping on the intermediate image data after the above thermal derating process, converting its original linear grayscale values ​​into nonlinear driven grayscale values ​​that conform to the visual characteristics of the human eye.

[0040] It's important to note that the luminance of a Micro-LED device is strictly linearly proportional to its driving current (PWM duty cycle), while the human eye's perception of brightness exhibits a non-linear logarithmic relationship (sensitive to changes in dark areas but insensitive to changes in bright areas). Directly using linear grayscale driving would result in harsh grayscale transitions in the projected light effect and a loss of detail in dark areas. The corrected target video frame data, when subsequently converted into a PWM driving signal, can compensate for the difference between the physical emission of the LED and human visual perception, ensuring a smooth and natural grayscale transition of the beam projected onto the road surface (especially at the obstruction edges of the adaptive high beam (ADB)). This eliminates visually harsh boundaries and abruptness, avoids wasting energy in visually insensitive high-brightness areas, and achieves a hardware-software synergy power-saving effect of "providing higher quality lighting visuals with lower absolute power consumption."

[0041] S3, the ASIC control chip 1 transmits the sub-screen data packets in parallel to the corresponding drive partition 4 through the data interface 41.

[0042] S4, each driver partition 4 receives and buffers sub-screen data packets.

[0043] S5, ASIC control chip 1 confirms whether all M sub-screen data packets have been transmitted. If so, it sends a global latch signal to each drive partition 4. Drive partition 4 synchronously flips the SRAM read / write pointer based on the global latch signal in the same clock cycle, and converts the digital grayscale value into a PWM signal through the internal PWM generator.

[0044] S6, the PWM signal is input to the driving unit 31 of each pixel driving module 3, and the driving unit 31 controls the Micro-LED 32 based on the PWM signal.

[0045] When the PWM signal is high, the constant current source switch of the drive unit 31 is closed, the drive unit 31 obtains the set drive current, and drives the corresponding Micro-LED 32 to light up; when the PWM signal is low, the constant current source switch of the drive unit 31 is open, cutting off the current loop, and the Micro-LED 32 is turned off.

[0046] It should be noted that the driving unit 31 obtains the driving current from the corresponding power input terminal 42, rather than sharing the power globally. This solves the voltage drop problem on the large-area silicon substrate, ensures the consistency of the positive voltage VF of all pixels, strictly controls the matrix brightness deviation within ± consistency, keeps it within the matrix, avoids local heat accumulation, and improves bonding reliability.

[0047] In this embodiment, the sub-screen data packet includes a header, The grayscale data of each pixel and the CRC check code are received. Each driver partition 4 will also perform CRC check based on the CRC check code when receiving sub-screen data packets.

[0048] Example 3: The difference from Embodiment 2 is that each driver uses a dual-buffering mechanism (Ping-Pong SRAM) to acquire sub-screen data packets. Two independent SRAMs A / B are used alternately as the "input buffer" and "output buffer" for sub-screen data packets. For example, when the SRAM is writing the Nth frame of sub-screen data for the first time, the display logic is reading the N-1th frame of sub-screen data from the SRAMB, realizing simultaneous reading and writing, zero dead zone switching, avoiding screen tearing during transmission, resulting in better display effect and improved user experience. In summary, the vehicle-mounted Micro-LED partitioned driving control system and its control method of the present invention, through the ASIC control chip 1, can decompose the original video frame into sub-screen data packets belonging to each driving partition 4, and output them to each driving partition 4 for display respectively. This effectively breaks through the data bandwidth bottleneck, achieves extremely low latency, and improves display efficiency. At the same time, it avoids the huge computational redundancy caused by traditional global centralized processing, and significantly reduces the dynamic power consumption of the main control chip during data throughput. The total power supply is distributed to each power input terminal 42, shortening the physical power supply path from the power supply to the array center. It solves the voltage drop problem on a large-area silicon substrate, ensures the consistency of the forward voltage VF of all pixels, strictly controls the matrix brightness deviation within ± consistency, and avoids local heat accumulation, thus improving bonding reliability. Furthermore, each drive partition 4 is connected to the ASIC control chip 1 via a corresponding data interface 41, and each drive partition 4 is connected to a power supply via a corresponding power input terminal 42. However, if the data line of any drive partition 4 breaks or the power supply is short-circuited, only the pixels of that drive partition 4 will be turned off. The system can still use the remaining 19 drive partitions 4 to reconstruct the safety light pattern, greatly improving the safety of nighttime driving and meeting automotive-grade safety requirements. In addition, this independent partition architecture allows the system to directly put non-working partitions into sleep mode or shut them down at the physical level in specific lighting scenarios (such as adaptive high beam shading scenarios where only partial illumination is required), avoiding low-current leakage losses caused by global power supply and achieving more refined regional energy consumption management.

[0049] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A vehicle-mounted Micro-LED zone drive control system, characterized in that, The system includes: ASIC control chip (1); A driving substrate (2) is provided, which includes a plurality of pixel driving modules (3) arranged in an array. The number of pixel driving modules (3) is N. Each pixel driving module (3) includes a driving unit (31) and a Micro-LED (32) that are electrically connected. Among them, all the pixel driving modules (3) are divided into M driving partitions (4), each driving partition (4) is provided with a corresponding data interface (41) and power input terminal (42), each driving partition (4) is connected to the ASIC control chip (1) through the corresponding data interface (41), and each driving partition (4) is connected to the power supply through the corresponding power input terminal (42); The ASIC control chip (1) can split the original video frame into sub-screen data packets belonging to each driving partition (4) and output them to each driving partition (4) for display.

2. The vehicle-mounted Micro-LED zone drive control system according to claim 1, characterized in that, The pixel driving module (3) is divided according to the number of the pixel driving module (3), and the number of driving partitions (4) is M.

3. The vehicle-mounted Micro-LED zone drive control system according to claim 2, characterized in that, The number of pixel driving modules (3) is N≥2.5W, and the number of pixel driving modules (3) in each driving partition (4) is: indivual.

4. The vehicle-mounted Micro-LED zone drive control system according to claim 1, characterized in that, The driving unit (31) corresponds one-to-one with the Micro-LED (32), and the driving unit (31) is electrically connected to the corresponding Micro-LED (32).

5. The vehicle-mounted Micro-LED zone drive control system according to claim 1, characterized in that, The data interface (41) is a QSPI interface.

6. The vehicle-mounted Micro-LED zone drive control system according to claim 1, characterized in that, Each of the power input terminals (42) is physically isolated from each other inside the drive substrate (2).

7. A method for zoned driving control of vehicle-mounted Micro-LEDs, characterized in that, The method employs an in-vehicle Micro-LED zone drive control system as described in any one of claims 1 to 6, and the method includes the following steps: S1, divide all the pixel driving modules (3) on the driving substrate (2) into M driving partitions (4). S2, the ASIC control chip (1) acquires the original video frame, performs thermal derating Mask superposition and Gamma correction on the original video frame, and cuts and divides the corrected original video frame to obtain M sub-picture data packets; Each sub-screen data packet corresponds to a driver partition (4). S3, the ASIC control chip (1) transmits the sub-screen data packets in parallel to the corresponding drive partition (4) through the data interface (41). S4, each of the drive partitions (4) receives and buffers the sub-screen data packets; S5, the ASIC control chip (1) confirms whether all M sub-screen data packets have been transmitted. If so, it sends a global latch signal to each of the driving partitions (4). The driving partitions (4) synchronously flip the SRAM read / write pointers in the same clock cycle based on the global latch signal and convert the digital grayscale value into a PWM signal through the internal PWM generator. S6, the PWM signal is input to the driving unit (31) of each pixel driving module (3), and the driving unit (31) controls the Micro-LED (32) based on the PWM signal.

8. The vehicle-mounted Micro-LED zone drive control method according to claim 7, characterized in that, In step S6, the driving unit (31) obtains driving current from the corresponding power input terminal (42) and lights up the corresponding Micro-LED (32).

9. The vehicle-mounted Micro-LED zone driving control method according to claim 7, characterized in that, The sub-screen data packet includes a header, The grayscale data of each pixel and the CRC check code are received by each of the driving partitions (4) and the sub-screen data packets are also subjected to CRC check based on the CRC check code.

10. The vehicle-mounted Micro-LED zone driving control method according to claim 7, characterized in that, Each of the aforementioned driver regions employs a double-buffering mechanism to acquire the sub-screen data packets.

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