LED headlamp assembly and control

Abstract

The present disclosure includes methods and systems for creating, using, and controlling LED headlamp topologies and matrices that require fewer components, power, and power while allowing for advanced features such as curve lighting. The disclosed methods and systems enable the use of smaller electrical systems, including control systems for LED and other headlamp topologies. Among other methods, the disclosed methods and systems may utilize pixel pairing and time multiplexing to manage current to minimize the power required on the circuit at a given time, thereby reducing the amount of material required to create LED headlight topologies as well as related methods and systems for creating, using, and controlling LED headlight topologies.

Description

[0001] This application is a divisional application of the invention patent application with international application number PCT / US2021 / 038658, international application date of June 23, 2021, entry into the Chinese national phase date of February 3, 2023, national application number 202180057980.7, and invention title "LED Headlight Assembly and Control". Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 043467, filed June 24, 2020, entitled “LED HEADLIGHT ASSEMBLY AND CONTROL,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to vehicle headlight design, and more specifically, to light-emitting diode (LED) headlight topology and matrix management. Background Technology

[0004] Some vehicles use headlight designs composed of light-emitting diodes (LEDs). The LED functions in automotive headlights can include various LED activation modes and brightness levels associated with different headlight settings. For example, LED functions may include, but are not limited to: low beam, low beam wide, high beam, turn signals, and daytime running lights (DRLs). The LED function of the low beam can be designed to illuminate a relatively close distance to the vehicle, but primarily concentrated in a single spot or area directly in front of the vehicle. The LED function of the low beam wide can be designed to illuminate a relatively close distance to the vehicle, but can be dispersed to project light in a cone shape from the lamp, thus projecting light to the sides of the vehicle. Therefore, headlights with low beam wide disperse light in a wider pattern compared to low beam. The LED function of the high beam can be designed to illuminate a relatively far distance to the vehicle, allowing the driver to see further in the dark. The LED function of the turn signals can be used to signal to oncoming traffic participants that the driver intends to turn in a certain direction. Daytime running lights can be used to increase a car's visibility to other vehicles and people outside the vehicle, even if the driver in the nearby area does not need the lights.

[0005] Other LED functions can include advanced features such as cornering lighting when the beam is aimed to provide illumination around turns and corners. For example, an LED function can be designed to output light from the LED to direct the light at the angle the vehicle is turning.

[0006] like Figure 1AAs shown, some current automotive headlight designs use multiple LEDs, with each LED connected to a separate driver circuit for activating and deactivating the connected LED. Figure 1A In the implementation shown, each driver circuit is connected to a separate LED, which in turn is grounded. Activating the driver circuit activates the individual LED. Some LEDs connected in this way can be used in a vehicle to provide high beam headlights, which allow the driver inside the vehicle to see over long distances at night. Alternatively, some LEDs within the headlights can be used as part of the low beam headlights. Other LEDs within the automotive lighting assembly can be used as daytime running lights.

[0007] In some LED-based headlight designs, individual LEDs are arranged in parallel and driven independently by separate LED drivers, meaning each LED string requires a single LED driver. Because each LED string may require sufficient power to drive its driver, this parallel design can be costly and potentially lead to poor system efficiency. For example, more power may be converted into heat rather than light, resulting in inefficient conversion of electrical energy into light. Summary of the Invention

[0008] One embodiment is a system for controlling light-emitting diodes (LEDs) in a vehicle. This embodiment includes an electronic control unit (ECU) configured to control current, voltage, or power to a first LED driver circuit; one or more LEDs electrically connected to the first LED driver circuit; and a first shunt connected to the ECU and configured to electrically bypass the one or more first LEDs to form one or more first LED functions. The system may include one or more second LEDs electrically connected to the first LED driver circuit. The system may include a second shunt connected to the ECU and configured to electrically bypass the one or more second LEDs to form one or more second LED functions. Time-division multiplexing, angle-domain multiplexing, or volt-second analysis can be used to control the first shunt to bypass the one or more first LEDs. Time-division multiplexing, angle-domain multiplexing, or volt-second analysis can be used to control the second shunt to bypass the one or more second LEDs. The ECU may be configured to prevent the total power supplied to the one or more first LEDs and the one or more second LEDs from reaching a predetermined threshold. The one or more first LEDs may include multiple LEDs that can be independently illuminated. The ECU may include various designs for illuminating LED groups within a headlight assembly. These designs may include designs selected from the following groups: high beam headlights, low beam spotlights, low beam wide beams, daytime running lights, and turn signals.

[0009] This disclosure includes a method for controlling a matrix of light-emitting diodes (LEDs) in a vehicle, the method comprising: receiving a signal to activate a group of LEDs in the vehicle; activating a first LED driver circuit to provide power to the group of LEDs; and controlling a first shunt connected to one or more LEDs in the group of LEDs to electrically bypass one or more LEDs in the group of LEDs. The method may further include monitoring the power drawn by the first LED driver circuit and bypassing the one or more LEDs if the power drawn exceeds a predetermined threshold. Activating the first LED driver circuit may include reading an LED lighting design to determine which LEDs should be bypassed by the first shunt. The design may be selected from a group consisting of: high beams, low beam spotlights, low beam wide beams, daytime running lights, or turn signals. Controlling the first shunt may include time-division multiplexing, angle-domain multiplexing, or volt-second analysis of the first shunt.

[0010] This disclosure includes a method for controlling a light-emitting diode (LED) matrix in a vehicle headlight assembly. The method includes: identifying a first pixel and a second pixel of the LED matrix powered by an LED driver; pairing the first pixel with the second pixel, wherein the pairing is optimized such that the total intensity of the pairing is less than the maximum intensity of any individual pixel powered by the LED driver; determining a threshold number of volt-seconds output by the LED driver; determining a set of LED functions associated with the LED driver; optimizing the set of LED functions of the vehicle headlight assembly; and associating the set of LED functions with the LED driver. The set of LED functions may be associated with an LED light design, which includes one of the following LED light designs: high beam, low beam spotlight, low beam wide beam, daytime running lights, or turn signals. Optimizing the set of LED functions of the vehicle headlight assembly may include optimization using any combination of time-division multiplexing, angular domain multiplexing, or volt-second analysis. Attached Figure Description

[0011] Embodiments of various inventive features will now be described with reference to the following accompanying drawings. Throughout the drawings, reference numerals may be used repeatedly to indicate the correspondence between referenced elements. The drawings are provided to illustrate exemplary embodiments described herein and are not intended to limit the scope of this disclosure.

[0012] Figure 1A An exemplary prior art circuit diagram is shown, featuring parallel driver LEDs for each LED function.

[0013] Figure 1B An exemplary circuit diagram with LED strings is shown according to an embodiment of the present invention, wherein each LED string includes an LED driver, one or more LED functions, and one or more splitters.

[0014] Figure 1C It shows Figure 1B An exemplary timing diagram of the operation of the exemplary circuit diagram shown.

[0015] Figure 2A An example of changing the current flowing through a series shunt topology is shown.

[0016] Figure 2B This illustrates another example of altering the current flowing through a series shunt topology.

[0017] Figure 3A An exemplary LED matrix arrangement is shown.

[0018] Figure 3B An exemplary LED matrix arrangement grouped into groups is shown.

[0019] Figure 4A An exemplary voltage measurement over time is shown for three staggered groups of LEDs.

[0020] Figure 4B An exemplary voltage measurement of an LED channel over time is shown.

[0021] Figure 5 A diagram illustrating how pixel pairing is optimized in the angular domain is shown.

[0022] Figure 6 A graph showing the volt-second analysis used to maximize the utilization of the LED driver is presented.

[0023] Figure 7A An exemplary flowchart is shown, illustrating an exemplary sequence of steps in optimizing pixel pairing.

[0024] Figure 7B An exemplary flowchart is shown, illustrating an exemplary sequence of steps in optimizing pixel pairing. Detailed Implementation

[0025] The various aspects of the systems, apparatus, and methods are described more fully below with reference to the accompanying drawings. However, the teachings of this disclosure may be implemented in many different forms and should not be construed as limited to any particular structure or function presented herein. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of this disclosure to those skilled in the art. Based on the teachings herein, those skilled in the art will understand that the scope of this disclosure is intended to cover any aspect of the novel systems, apparatus, and methods disclosed herein, whether implemented independently of or in combination with any other aspect of the invention. For example, any number of aspects set forth herein may be used to implement an apparatus or practice a method. Furthermore, the scope of the invention is intended to cover such apparatuses or methods that are practiced using additional structures, functions, or structures and functions that are attached to or different from the aspects of the invention set forth herein. It should be understood that any aspect disclosed herein may be embodied by one or more elements of the claims.

[0026] While specific aspects are described herein, numerous variations and substitutions of these aspects fall within the scope of this disclosure. Although some benefits and advantages of preferred aspects are mentioned, the scope of this disclosure is not intended to be limited to specific benefits, uses, or purposes. Rather, aspects of this disclosure are intended to be broadly applicable to various wireless technologies, system configurations, networks, and transport protocols, some of which are illustrated by way of example in the accompanying drawings and the following description of preferred aspects. The detailed description and drawings are merely illustrative and not limiting of this disclosure, the scope of which is defined by the appended claims and their equivalents.

[0027] This disclosure includes methods and systems for creating, using, and controlling LED headlight topologies and matrices that require fewer components, power, and specifications compared to existing systems, while allowing advanced features such as cornering lighting. The disclosed methods and systems enable easier manufacturing and repair of LEDs and other headlight topologies. Embodiments of the disclosed methods and systems enable the use of smaller, lower-power electrical systems, including control systems for LEDs and other headlight topologies. In other methods, other embodiments may utilize pixel pairing and time multiplexing to manage the current flowing to each LED, minimizing the power required on the circuit at a given time, thereby reducing the amount of material required to create LED headlight topologies and the associated methods and systems for creating, using, and controlling LED headlight topologies.

[0028] In some implementations of this system, groups of multiple LEDs are connected in series to the same LED driver and driven as a single LED string. This design allows multiple LED lights and functions to be assigned to a single LED driver. In some implementations, the system uses a splitter to control the individual LED functions to adjust the brightness of each LED or LED group without affecting the brightness of other LEDs in the same LED string. For example, reducing the number of components by reducing the number of LED drivers can lower system costs, reduce printed circuit board (PCB) size, and increase space for other electrical components. This allows for smaller LED headlight designs to fit a variety of headlight configurations and designs, and also reduces circuit complexity. Reduced complexity can lead to improvements in manufacturing, repairing, and replacing headlights using this system. This embodiment can also result in a reduction in the size of the housing or heat sink for a particular headlight.

[0029] Typically, systems with fewer LED drivers also reduce the amount of energy and / or power required to operate, thus reducing power draw and increasing battery life if power is drawn from a battery (e.g., in an electric vehicle). Therefore, the currently disclosed series-shunt LED topology can lead to improved electrical efficiency, reduced size and weight, and lower cost. Series-shunt topologies can be utilized to improve electrical efficiency and reduce costs in any high-power LED lighting system, although this disclosure focuses on its use in automotive headlights.

[0030] like Figure 1B As shown, a series split topology that supports five LEDs requires only two driver circuits, namely LED driver 1 and LED driver 2. Figure 1B The illustrated series shunt topology includes LED shunts for individual control of each LED. Placing a shunt at each LED function allows for independent control of each LED function by activating the shunt using a control system connected to each shunt. As shown in the figure, V in Connected to LED driver 1, driver 1 powers LED string 1. LED driver 1 supplies power to the first LED (LED function 1) and the second LED (LED function 2). LED function 1 is also connected to a first LED dimming splitter, which allows the power passing through the LED to be split and is used to controllably dim or brighten LED function 1. Figure 1B As shown, LED string 1 also includes LED function 2 connected to a second LED dimming splitter on LED string 1. By activating each splitter, the control system can control the brightness of the first or second LED in LED string 1, and only a single driver is needed to provide power to LED string 1 and activate the LEDs.

[0031] Similarly, Figure 1BAs shown, LED driver 2 is connected to V in It is configured to drive a group of three LEDs (LED functions 1, 2, and 3). Each of the three LEDs is connected to a separate shunt circuit, which can be used to dim or brighten each LED without affecting the functions of other LEDs in the same series.

[0032] To operate each shunt, the control system can turn the shunt off (disconnect it), which allows current to flow through the LED that functions, thus illuminating the LED. When the shunt for an LED function is turned on, current can be shunted around the LED that functions, so the LED may not be turned on because power is bypassing the LED. Alternatively, the shunt can be used to dim the LED instead of turning it off completely.

[0033] To dim LEDs, each shunt can be modulated at a frequency high enough to avoid noticeable flicker but low enough to make switching losses negligible. For example, a shunt can be modulated to operate at approximately 200 Hz. Alternatively, a shunt can be modulated to operate at frequencies of approximately 100, 120, 130, 144 Hz, or even higher than 200 Hz, depending on design constraints. An LED driver supplying power to each LED string can maintain a constant current through the string, such that the current through any given LED function can be controlled by its associated shunt. Therefore, a shunt can drive multiple LED functions from the same LED driver while maintaining complete control over the relative brightness of each LED function. Shunts can also be useful because they can be configured to use very little PCB space and can be relatively low in complexity compared to other electrical components such as LED drivers and boost converters.

[0034] Figure 1C It is shown Figure 1B Exemplary voltage levels and reference values ​​for LED functions 1, 2, 3, 4, and 5. Figure 1B The exemplary series shunt topology shown is illustrated in the timing diagram of the corresponding voltage levels that can be seen on the two LED strings. LED functions 1 and 2 are connected in series to form LED string 1, and LED functions 3, 4, and 5 are connected in series to form LED string 2. Figure 1C It also explains how to reuse different LED functions to avoid any overvoltage conditions in any LED string or LED function. For example, LED function 3 could be a daytime running light, while LED function 5 could be a low beam headlight. Since the daytime running lights operate during the day and the low beam headlights operate in the dark, these lights cannot be used simultaneously. Thus, Figure 1C The exemplary time multiplexing shown illustrates how LED function 3 can be used as a daytime running light, and is only turned on and activated when LED function 5, which is used as a low beam wide headlight, is off, and vice versa.

[0035] In another example, LED function 1 and LED function 2 can be used as the second daytime running light and the third daytime running light, respectively. Figure 1C The exemplary time multiplexing shown illustrates how LED function 1, as a second daytime running light, is only turned on when LED function 2, as a third daytime running light, is off, and vice versa. These examples demonstrate how time multiplexing and / or interleaving LED driver channels can allow additional LED functions without increasing the positive voltage of the entire LED string.

[0036] Figure 2A and 2B An example of varying current guided by a shunt topology is shown. Changing the current allows for different combinations of LED functionality, which can be used in specific situations. For example, Figure 2A The decoupling activation of the high beam LEDs shown can prevent the activation of the high beam LED function used for nighttime driving, thereby reducing the risk to oncoming traffic participants. In another example, Figure 2B The diagram depicts combinations of activated LED functions, which may include only daytime running lights (DRLs) for daytime driving. Figure 2B As shown, LED driver 1 is branched to bypass the low beam spotlight, low beam wide beam, and high beam LEDs, and only connects the DRL1 LED function to be activated. Similarly, LED driver 2 is connected to DRL2 and DRL3, so that all three DRL systems are activated, as shown. Figure 2B As shown. Figure 2A and 2B It also shows how to use diodes and shunts to power the turn signal from either LED driver.

[0037] Figure 2A and 2B The description in the document can reflect all LED functions activated by LED drivers 1 and 2, but not all LED functions need to be activated at the same time. Figure 2A and 2B An example mode of an LED driver is shown, which can activate one or more LED functions at a time and alternate and / or multiplex signals to each associated LED function.

[0038] The series shunt topology described here uses time multiplexing to share a single LED driver across multiple LED functions. Time multiplexing can be used because the shunt allows for individual control of different LED functions, enabling the interleaving and multiplexing of LED functions in time. When there is a large difference between the input voltage to the LED driver and the output voltage from the LED driver, a hysteretic LED driver can suffer from poor electrical efficiency. By stacking multiple LED functions and multiplexing them, the series shunt topology can reduce the input-output voltage difference and improve the electrical efficiency of the LED driver.

[0039] The reduction in the input-output voltage difference can be attributed to the time multiplexing of LED functions driven by the same LED driver. For example, Figure 2A LED driver 1 can drive both DRL1 and the low beam LED because the maximum LED driver voltage will not simultaneously cover both the low beam LED and DRL1. The LED driver will use time multiplexing to drive DRL1, and the low beam LED will operate at different times. Similarly, Figure 2B In this series shunt topology, DRL2 and DRL3 will never be on simultaneously, so LED driver 2 can drive both DRL2 and DRL3 because they will never simultaneously contribute the maximum LED driver voltage. Due to this increased electrical efficiency and / or reduced power extraction, the boost converter used in the series shunt topology can be physically smaller than the boost converter in other topologies. It should be recognized that the series shunt topology can be implemented using any commercially available LED driver.

[0040] In some implementations, LED matrix control systems result in large, expensive ECUs that are inefficient and susceptible to large power / current surges affecting upstream components. In some implementations, LED matrix control methods typically align the start times of all pixels in an LED group. As used herein, a "pixel" can be an individual LED. A pixel can be part of an LED group comprising multiple individual LEDs, each of which can be individually powered to provide a specific light pattern within the LED group. By aligning the start times of all pixels in the LED group, all pixels are turned on simultaneously and turned off simultaneously as needed to achieve the desired brightness. This results in maximum power / current being drawn from upstream components for a short period. To accommodate the surge, upstream components (e.g., wires, high-side drivers, etc.) need to be resized to accommodate the power draw, and the LED matrix module needs to be divided into LED groups, each with a dedicated LED driver. Furthermore, the higher input-output voltage difference leads to further electrical inefficiency. This results in each LED driver controlling a small segment of LEDs. This design inefficiently utilizes LED drivers and requires several LED drivers to drive the matrix. This control method allows for fewer components, higher system power, component, and space efficiency, and lower system cost. The system and method can combine multiple groups to form channels. Instead of using one LED driver per group, this method can use one LED driver per channel, thereby reducing the number of LED drivers required. The system and method can further improve LED system efficiency by grouping pixels to utilize LED drivers more efficiently. This control of these LEDs can also limit inrush current by staggering the activation cycles of the individual pixels. Embodiments of the system can be used to control any LED matrix, including but not limited to the series-branched LED topology described above.

[0041] Figure 3A and 3B An exemplary LED matrix arrangement is shown. Figure 3AA 28×4 matrix of individual pixels is shown, where each pixel can operate at a set brightness within the light unit. The brightness of a given pixel can be determined by the currently active LED function (e.g., high beam, low beam, or daytime running lights). Another LED function could be cornering illumination, a feature that changes the headlight directionality as the vehicle prepares to round a corner, during or after a turn, or adjusts to a road curve. In prior art implementations, cornering illumination is mechanically implemented, where an electric motor rotates the headlight hardware such that the beam is angled toward the curve. In this embodiment, cornering illumination is electronically implemented by adjusting pixel brightness to focus the beam toward the curve. In some implementations, pixels facing the curve can increase brightness, while pixels away from the curve can dim. In some implementations, cornering illumination can be achieved by generating an interference pattern from the light emitted by each pixel based on the brightness of each pixel.

[0042] Figure 3B Show how to Figure 3A Individual pixels are grouped as possible configurations for the group. For example... Figure 3B As shown, the LEDs can be grouped into nine LED groups, each of which is individually controllable. In some embodiments, Figure 3A It describes the usage of each pixel, and Figure 3B The use of groups is described. These nine groups can also be grouped into channels. To form channels, groups that draw more power can be paired with groups that draw less power, ensuring that the amount of power used never exceeds the maximum value of the associated LED driver, which will drive power to the multiple groups grouped to form channels. In some implementations, one or more groups with lower utilization will be paired with one or more groups with higher utilization, ensuring that the power required by the group does not exceed the maximum power available from the LED driver. Pixels within each group can also be individually interleaved to eliminate high power / current surges that occur. Under this control method, one LED driver can drive each channel. Therefore, this control method can maximize the utilization of the LED driver while still achieving advanced features such as cornering lighting, which requires very dynamic control of pixel brightness.

[0043] In some implementations, one or more groups with lower utilization will be paired with one or more groups with higher utilization, such that the power required by the group when performing any particular LED function does not exceed the maximum power available from the LED driver. Utilization can be measured as the average power draw, brightness, or the percentage of time that typically draws the threshold current. Pixels within each group can also be individually interleaved to eliminate large power / current surges that occur during any particular LED function.

[0044] Figure 4A and 4BThe voltage levels in an LED matrix with staggered pixel activation times are shown. Figure 4A An exemplary voltage measurement over time is shown for three interleaved LED groups that can be controlled by a single LED driver, where the LED groups are configured to form a channel. By interleaving, the LED groups do not need to be activated simultaneously. Instead, each LED group can be activated only when needed, thus distributing power surges over time and avoiding large surges. An interleaved LED matrix can support overlap in LED group activation by combining multiple groups together, ensuring that even when activated simultaneously, these groups do not draw more power than the driver can support.

[0045] Figure 4B An exemplary voltage measurement of an LED channel over time is shown. This channel can be formed by combining at least two groups of LEDs together. Each channel can be controlled by a dedicated LED driver. By interleaving, the LED driver can utilize more time compared to other methods that leave the LED driver idle (at 0 voltage) for relatively long periods between LED function changes. As shown, interleaving minimizes peak channel voltage and prevents the system from exceeding the driver's maximum supported voltage.

[0046] Figure 5 This diagram illustrates how pixel pairing is optimized in the angular domain of cornering lighting. As mentioned above, electronic cornering lighting may require dynamic dimming and brightening of individual pixels. Figure 5This illustrates the bend angles and intensities of pixels A and B, as well as the sum of their intensities. Pixel intensity can depend on the bend angle and can change as the bend angle changes. In some implementations, bend lighting can include a beam pattern for bend angles ranging from -10 degrees to 5 degrees or from -5 degrees to 10 degrees, depending on whether the beam is emitted from the left or right side of the vehicle. In this example, -10 degrees can be -10 degrees relative to light illuminating directly ahead, and can be -10 degrees to the left or right. In some implementations, these bend angles can be configured to change with a resolution of 0.1 degrees (e.g., allowing bend angles of 0, 0.1, 0.2, 0.3, and 0.4 degrees, etc.). Optimized pixel pairing can allow adjustment of the intensity of each pixel during LED operation while ensuring that the pixel pair never exceeds 100% of the combined intensity. Intensity can refer to the voltage, current, and / or power supplied to the pixel or the brightness of the light emitted from the pixel. It should also be noted that when pulse width modulation is implemented to power pixels, the intensity of a pixel can be related to its on-time. For example, you cannot provide each pair of pixels with more voltage, current, and / or power than is available to a single pixel at any given time. In some implementations, each pair of pixels cannot emit more light than the maximum light a single pixel can emit. A pixel pair with 100% intensity at all angles could mean that the two pixels are perfectly matched because any off-time in one pixel is filled by the on-time of the other pixel.

[0047] like Figure 5 As shown, for all angles, the pixel intensity does not necessarily need to sum to 100%, but ideally the sum should be as close to 100% as possible without exceeding it. By optimizing all pixel pairs to 100% intensity, the input-output voltage difference can be minimized, increasing electrical efficiency and other factors disclosed herein. For example, some pixels may have maximum intensity at negative angles, while other pixels may have maximum intensity at positive angles. These pixels with maximum intensity at opposite angles can be paired together such that when one is dark, the other is bright. Paired pixels do not need to be adjacent to each other or laterally adjacent. Alternatively, the intensity of a pixel pair can be optimized to a sum close to 200%, where 200% represents the maximum intensity of the two pixels the LED driver is designed to power.

[0048] Pixel pairing can be optimized in both the angular and temporal domains. For example, angular domain optimization would be based on pairing pixels using the bending angle of light. In another example, temporal domain optimization would be based on the utilization rate during time multiplexing. Pixel pairing can be optimized in both the angular and temporal domains simultaneously. Pixel pairing can also be optimized in the volt-second domain (described here).

[0049] Figure 6This is a graph illustrating volt-second analysis used to maximize the utilization of an LED driver. When multiple LED functions are multiplexed, volt-second analysis (also known as Tetromino analysis) can be used to optimize LED driver channels. Volt-second analysis can observe the maximum capability of an LED driver based on an area measured in volt-seconds. Figure 6 The rectangular portion in the diagram represents the LED. Using volt-second analysis, the LED driver (or the LED driver controller) can determine the function of the LED to be driven by examining the input voltage and its PWM. For example, if the input voltage is between 30 and 50V and the PWM of the input voltage is between 0 and 90%, then the LED has the function of driving the LED. Figure 6 The exemplary LED driver system, plotted as a volt-second analysis curve, will drive the high-beam LED function. If the input voltage is between 10V and 30V and the PWM of the input voltage is between 10% and 100%, then... Figure 6 The same example LED driver system shown in the diagram will drive a low-beam wide-angle LED function. Using volt-second analysis can lead to simpler designs for control schemes of multiple LED functions driven by a single LED driver. An LED driver can support as many different functions as possible until its volt-second capacity is fully utilized. Increasing the LED driver output voltage increases the total available volt-second area. Increasing the LED driver current reduces the volt-second area required for each function, thus allowing each LED driver to have more functions. Therefore, the utilization of the LED driver can be maximized (e.g., the volt-second area of ​​the LED driver is occupied by the LED function) by adjusting the driver voltage and current.

[0050] Figure 7A and 7B This is an example flowchart illustrating a sequence of steps in optimizing pixel pairing. This flowchart helps ensure that pixels are paired as efficiently as possible for advanced features such as cornering lighting. The method also allows us to assign a numerical value to each possible pixel pair in a channel powered by an LED driver, where the value represents the degree of quality of the pixel pairing.

[0051] Figure 7A This represents an exemplary series of steps that can be described as corner domain optimization. Corner domain optimization describes the utilization of each pixel in a channel (e.g., for high-level features such as corner lighting) and uses that utilization to determine pixel pairings.

[0052] Figure 7BThis represents an example sequence of steps that can be described as time-domain optimization. Time-domain optimization describes the utilization of pixels, groups, and / or channels, and their corresponding peak voltages or currents over a time period. Time-domain optimization can use multiplexing or interleaving techniques to ensure that peak voltages or currents (whether pixel, group, or channel peak voltages or currents) are not exceeded in the electrical system, while providing the necessary voltages and / or currents to the LEDs for targeted illumination or beam patterning and brightness.

[0053] The foregoing disclosure is not intended to limit this disclosure to the exact form disclosed or a particular field of use. Therefore, various alternative embodiments and / or modifications of this disclosure are possible, whether expressly described or implied herein. Since embodiments of this disclosure have been so described, those skilled in the art will recognize that changes in form and detail may be made without departing from the scope of this disclosure. Therefore, this disclosure is defined only by the claims.

[0054] In the foregoing specification, this disclosure has been described with reference to specific embodiments. However, as those skilled in the art will appreciate, the various embodiments disclosed herein may be modified or otherwise implemented in various other ways without departing from the spirit and scope of this disclosure. Therefore, this specification is to be considered illustrative and is intended to teach those skilled in the art the various ways of making and using the disclosed motor assemblies. It should be understood that the forms of this disclosure shown and described herein are considered representative implementations. Equivalent elements, materials, processes, or steps may be substituted for those representatively illustrated and described herein. Furthermore, certain features of this disclosure may be utilized independently of the use of other features, all of which will be apparent to those skilled in the art after benefiting from this specification. Expressions such as “comprising,” “including,” “incorporated,” “consisting of,” “having,” and “is” are used to describe and claim this disclosure and are intended to be interpreted in a non-exclusive manner, allowing for the presence of items, assemblies, or elements not explicitly described. References to the singular are also interpreted to refer to the plural.

[0055] Furthermore, the various implementations disclosed herein should be considered illustrative and explanatory, and in no way should they be construed as limiting this disclosure. All linking references (e.g., attachment, affixation, coupling, connection, etc.) are provided only to aid the reader in understanding this disclosure and are not intended to be limiting, particularly regarding the location, orientation, or use of the systems and / or methods disclosed herein. Therefore, linking references, if any, will be interpreted broadly. Moreover, such linking references do not necessarily imply that two elements are directly interconnected.

[0056] In addition, all numerical terms such as, but not limited to, “first,” “second,” “third,” “primary,” “secondary,” “main,” or any other common and / or numerical terms should be regarded only as identifiers to help the reader understand the various elements, embodiments, variations, and / or modifications of this disclosure, and may not impose any limitations, particularly regarding the order or priority of any element, embodiment, variation, and / or modification relative to another element, embodiment, variation, and / or modification.

[0057] It should also be understood that one or more elements depicted in the accompanying drawings may also be implemented in a more discrete or integrated manner, or in some cases even removed or rendered inoperable, which may be useful depending on the specific application. Furthermore, any signal shadows in the accompanying drawings should be considered exemplary only and not limiting, unless specifically stated otherwise.

Claims

1. An LED lighting system for a vehicle, comprising: Multiple LED driver circuits; Multiple LEDs, wherein multiple subsets of the multiple LEDs implement corresponding LED functions, and the multiple subsets include at least a first subset implementing a first LED function and a second subset implementing a second LED function; Multiple splitters are configured to selectively bypass a specific LED among the multiple LEDs; and The controller is configured to control the plurality of splitters such that: When the first LED function is activated, the plurality of splitters are configured such that the first subset of LEDs receives power from at least two of the plurality of LED driver circuits, and at least one LED in the second subset of LEDs does not receive power. as well as When the second LED function is activated, the plurality of splitters are configured such that the second subset of LEDs receives power from the at least two LED driver circuits; The power draw from each activated LED function is distributed to at least two of the plurality of LED driver circuits.

2. The system of claim 1, wherein the plurality of LEDs are arranged in a plurality of LED strings, each LED string being connected to a corresponding LED driver circuit, and wherein each LED string includes one or more LEDs from each subset of at least two subsets of the plurality of subsets.

3. The system of claim 1, wherein the plurality of LED functions include LED functions selected from the group consisting of: high beam headlights, low beam spotlights, low beam wide beams, daytime running lights, parking lights, turn signals, and cornering lights.

4. The system according to any one of claims 1 to 3, wherein the controller is configured to use time-division multiplexing to control the plurality of splitters to selectively activate and bypass LEDs within a given LED string connected to a single LED driver circuit.

5. The system according to any one of claims 1 to 3, wherein the controller is configured to prevent the total power drawn from any single LED driver circuit of the plurality of LED driver circuits from exceeding a predetermined threshold.

6. The system according to any one of claims 1 to 3, wherein the first LED function and the second LED function share at least one common LED that simultaneously belongs to the first subset and the second subset.

7. The system according to any one of claims 1 to 3, wherein the controller is configured to change the bypassed LEDs by reconfiguring the plurality of splitters to switch between the first LED function and the second LED function without disabling the plurality of LED driver circuits.

8. The system according to any one of claims 1 to 3, wherein: The first subset of LEDs does not include at least one LED in the second subset; The second subset of LEDs does not include at least one LED in the first subset; and The plurality of splitters can be controlled to bypass at least one LED in the second subset when the first LED function is activated, and to bypass at least one LED in the first subset when the second LED function is activated.

9. The system according to claim 8, wherein: The first subset of LEDs and the second subset of LEDs share one or more of the plurality of LEDs; and When the first LED function is activated, and when the second LED function is activated, the one or more LEDs receive power.

10. A method for controlling an LED matrix in a vehicle headlight assembly, the LED matrix comprising a plurality of LEDs and a plurality of splitters, the plurality of LEDs being arranged in a plurality of LED strings connected to respective LED driver circuits, each splitter being configured to selectively bypass at least one LED, the method comprising: Determine the first LED function to be activated, wherein the first LED function is implemented by a first subset of the plurality of LEDs; The plurality of splitters are configured such that LEDs not belonging to the first subset are bypassed, and LEDs belonging to the first subset obtain power from at least two LED driver circuits; as well as In response to determining that a second LED function is to be activated, the plurality of splitters are reconfigured such that LEDs not belonging to a second subset implementing the second LED function are bypassed, and LEDs belonging to the second subset receive power from the at least two LED driver circuits, the second subset not including at least one LED in the first subset; The power draw of each activated LED function is distributed to the at least two LED driver circuits.

11. The method of claim 10, further comprising: Monitor the power draw of each LED driver circuit and adjust the shunt configuration to prevent any single LED driver circuit from drawing power beyond a predetermined threshold.

12. The method of claim 10, wherein configuring the plurality of splitters includes time-division multiplexing, angle-domain multiplexing, or volt-second analysis.

13. The method according to any one of claims 10 to 12, further comprising: Select the first LED function and the second LED function from a plurality of LED lighting designs stored in the controller, wherein the LED lighting designs define a subset of LEDs to be activated for each LED function.

14. The method according to any one of claims 10 to 12, wherein the first LED function and the second LED function are activated simultaneously, and wherein configuring the plurality of splitters comprises: The first subset and the second subset are time-division multiplexed so that the power draw from each LED driver circuit remains below a predetermined threshold at each time point.

15. The method according to any one of claims 10 to 12, wherein reconfiguring the plurality of splitters comprises: While keeping the at least two LED driver circuits operating continuously, the bypassed LED is changed.

16. The method according to any one of claims 10 to 12, wherein: The first subset of LEDs does not include at least one LED in the second subset; and The plurality of splitters can be controlled to bypass at least one LED in the second subset when the first LED function is activated, and to bypass at least one LED in the first subset when the second LED function is activated.

17. The method of claim 16, wherein: The first subset of LEDs and the second subset of LEDs share one or more of the plurality of LEDs; and When the first LED function is activated, and when the second LED function is activated, the one or more LEDs receive power.

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