LED headlight assembly and control

Abstract

The present disclosure includes methods and systems for creating, using, and controlling LED headlight topologies and matrices that require fewer components, electricity, and power while enabling advanced features such as curved lighting. The disclosed methods and systems can enable the use of smaller electrical systems, including control systems for LED and other headlight topologies. The disclosed methods and systems can also utilize pixel pairing and time multiplexing, among other methods, to manage electrical flow to minimize the power required on a circuit at a given time, thus reducing the amount of materials needed to create the LED headlight topologies, as well as related methods and systems for creating, using, and controlling LED headlight topologies.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims priority to U.S. Provisional Patent Application No. 63 / 043467, filed Jun. 24, 2020, entitled "LED HEADLIGHT ASSEMBLY AND CONTROL", the entire contents of which are incorporated herein by reference.

[0002] This disclosure relates to the design of vehicle headlights, and more specifically, to the topology and matrix management of light - emitting diode (LED) headlights.

Background Art

[0003] Some vehicles use headlight designs composed of light - emitting diodes (LEDs). The LED functions in automotive headlights can include various LED activation patterns and brightness levels related to different headlight settings. For example, the LED functions can include, but are not limited to, low - beam spot, low - beam wide, high - beam, turn, and daytime running lamp (DRL). The low - beam spot of the LED function can be designed to illuminate a relatively short distance from the vehicle, but is mainly focused on one spot or the area directly in front of the vehicle. The low - beam wide of the LED function can be designed to illuminate a relatively short distance from the vehicle, but can be dispersed in a conical shape from the light to project light onto the sides of the vehicle. Thus, the headlight disperses light in a wider pattern in low - beam wide compared to the low - beam spot. The high - beam of the LED function can be designed to illuminate a relatively long distance from the vehicle, enabling the driver to see farther in the dark. The turn of the LED function can be used to signal to oncoming vehicles that the driver is about to change direction. The daytime running lamp can be used to enhance the visibility of the vehicle to other vehicles and people outside the vehicle even when the driver does not need the light to illuminate nearby areas.

[0004] Other LED features may include advanced functions such as bent lighting, if the goal is for the light beam to provide illumination around turns and corners. For example, the LED feature may be designed to emit light from the LEDs and direct the light towards the angle at which the vehicle is turning.

[0005] As shown in Figure 1A, some current automotive headlight designs use multiple LEDs, each LED connected to an individual driver circuit used to activate and deactivate the connected LEDs. In the implementation shown in Figure 1A, each driver circuit is connected to an individual LED, and each individual LED is connected to ground. When the driver circuit is activated, a single LED is activated. Several LEDs connected in this manner can be used in a vehicle to provide high-beam front headlights that allow the driver inside the vehicle to see long distances at night. Alternatively, some LEDs in the headlamp may be used as part of the low beam. Other LEDs in the automotive lighting assembly can be used as daytime running lights.

[0006] In some light-emitting diode (LED) based headlight designs, individual LED functions are arranged in parallel and driven independently by separate LED drivers, meaning that a single LED driver is required for each LED string. This parallel design can be cost-ineffective and lead to reduced system efficiency, as each LED string may require enough power to drive its own LED driver. For example, more power may be converted into heat rather than light, reducing the efficiency of converting electrical energy into light. [Overview of the project]

[0007] 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 one or more of the 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 one or more of the second LEDs to form one or more second LED functions. The first shunt may be controlled using time-division multiplexing, angular-domain multiplexing, or volt-second analysis and may bypass one or more of the first LEDs. The second shunt may be controlled using time-division multiplexing, angular-domain multiplexing, or volt-second analysis and may bypass one or more of the second LEDs. The ECU can be configured to prevent the total power supplied to a first shunt for one or more first LEDs and one or more second LEDs from reaching a predetermined threshold. The one or more first LEDs may include multiple LEDs that can be illuminated independently. The ECU may include various profiles for illuminating the set of LEDs in the headlight assembly. The profiles may include those selected from the group consisting of high beam, low beam spot, low beam wide, daytime running light, and turn light.

[0008] This disclosure includes a method for controlling a light-emitting diode (LED) matrix in a vehicle, the method comprising: receiving a signal to activate a set of LEDs in the vehicle; activating a first LED driver circuit to supply power to the set of LEDs; and controlling a first shunt connected to one or more LEDs in the set of LEDs to electrically bypass one or more LEDs in the set of LEDs. The method may further include monitoring the power consumed by the first LED driver circuit and bypassing one or more LEDs if the power consumption exceeds a predetermined threshold. The step of activating the first LED driver circuit may include reading an LED lighting profile to determine which LEDs should be bypassed by the first shunt. The profile may be selected from the group consisting of high beam, low beam spot, low beam wide, daytime running light, or turn. The step of controlling the first shunt may include time-division multiplexing, angular domain multiplexing, or volt-second analysis of the first shunt.

[0009] This disclosure includes a method for controlling a light-emitting diode (LED) matrix in a vehicle headlight assembly, the method comprising: identifying a first pixel and a second pixel of an LED matrix powered by an LED driver; pairing the first pixel and 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 volt-second threshold for output by the LED driver; determining a set of LED functions to associate with the LED driver; optimizing a set of LED functions in a vehicle headlight assembly; and associating a set of LED functions with an LED driver. The set of LED functions may be associated with an LED light profile that includes one of the following LED light profiles: high beam, low beam spot, low beam wide, daytime running light, or turn. Optimizing a set of LED functions in a vehicle headlight assembly may include optimizing using any combination of time-division multiplexing, angular domain multiplexing, or volt-second analysis. [Brief explanation of the drawing]

[0010] Next, various embodiments of the features of the present invention will be described with reference to the following drawings. Throughout the drawings, reference numerals may be reused to indicate correspondences between the referenced elements. The drawings are provided to illustrate exemplary embodiments described herein and are not intended to limit the scope of the disclosure. [Figure 1A] An example circuit diagram of a conventional technology having parallel driver LEDs corresponding to each LED function is shown.

[0011] [Figure 1B] An exemplary circuit diagram of an LED string according to one embodiment of the present invention is shown, wherein each LED string includes an LED driver, one or more LED functions, and one or more shunts.

[0012] [Figure 1C] Shows an exemplary timing diagram for the operation of the exemplary circuit diagram shown in FIG. 1B.

[0013] [Figure 2A] Shows an example of the changing current flow through a series-shunt topology.

[0014] [Figure 2B] Shows another example of the changing current flow through a series-shunt topology.

[0015] [Figure 3A] Is a diagram showing an exemplary LED matrix arrangement.

[0016] [Figure 3B] Is a diagram showing an exemplary LED matrix arrangement grouped into banks.

[0017] [Figure 4A] Shows exemplary voltage measurements over time for three interleaved LED banks.

[0018] [Figure 4B] Shows exemplary voltage measurements over time for an LED channel.

[0019] [Figure 5] Shows a graph showing how pixel pairing can be optimized in an angular region.

[0020] [Figure 6] Shows a graph showing the volt-second analysis used to maximize the utilization of an LED driver.

[0021] [Figure 7A] Shows an exemplary flowchart showing an exemplary series of steps for optimizing pixel pairing.

[0022] [Figure 7B]An exemplary flowchart is shown illustrating an exemplary sequence of steps in optimizing pixel pairing. [Modes for carrying out the invention]

[0023] 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 embodied in many different forms and should not be construed as being limited to any particular structure or function presented through this disclosure. Rather, these aspects are provided so as to make this disclosure thorough and complete and fully convey the scope of this disclosure to those skilled in the art. Based on the teachings of this specification, 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, an apparatus can be implemented or a method can be implemented using any number of aspects described herein. Furthermore, the scope of the invention is intended to cover any such apparatus or method implemented using, in addition to, the various aspects of the invention described herein, or other structures, functions, or structures and functions other than the various aspects of the invention described herein. It should be understood that any aspect disclosed herein may be embodied by one or more elements of the claims.

[0024] While certain embodiments are described herein, many variations and substitutions of these embodiments fall within the scope of this disclosure. Although some advantages and benefits of preferred embodiments are mentioned, the scope of this disclosure is not intended to be limited to any particular advantage, use, or purpose. Rather, embodiments of this disclosure are intended to be broadly applicable to different wireless technologies, system configurations, networks, and transmission protocols, some of which are illustrated in the drawings and the following description of preferred embodiments. The detailed description and drawings are illustrative rather than limiting, and the scope of this disclosure is defined by the appended claims and their equivalents.

[0025] This disclosure includes methods and systems for creating, using, and controlling LED headlight topologies and matrices that require fewer components, electricity, and power compared to conventional systems, while enabling advanced functions such as bent lighting. The disclosed methods and systems can enable easier manufacturing of LED and other headlight topologies, as well as easier repair of LED and other headlight topologies. Embodiments of the disclosed methods and systems can enable the use of smaller, lower-power electrical systems, including control systems for LED and other headlight topologies. Other embodiments utilize, among other methods, pixel pairing and time multiplexing to manage the electrical flow to each LED, thereby minimizing the power required on the circuit at a given time, and thus reducing the amount of material required to create the LED headlight topology, as well as the associated methods and systems for creating, using, and controlling the LED headlight topology.

[0026] In some implementations of this system, groups of 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 controls individual LED functions without affecting the brightness of other LEDs in the same LED string by adjusting the brightness of individual LEDs or groups of LEDs using shunts. Reducing the number of components by, for example, reducing the number of LED drivers can lower system costs, shrink the size of the printed circuit board (PCB), and increase space for other electrical components. This allows for smaller LED headlight designs to be adapted to various headlight configurations and designs, and also reduces circuit complexity. Reduced complexity can lead to improvements in the manufacturing, repair, and replacement of headlights utilizing this system. This embodiment can also reduce the size of the housing or heatsink using specific headlamps.

[0027] In general, systems with fewer LED drivers can also reduce the amount of energy and / or power required to function, and therefore reduce power consumption and extend battery life, especially when power is drawn from a battery, such as in electric vehicles. Thus, the series-shunt LED topology of this disclosure can result in improved electrical efficiency, reduced size and weight, and cost savings. While the series-shunt topology can be used to improve electrical efficiency and reduce costs in any high-power LED lighting system, this disclosure focuses on its use in automotive headlights.

[0028] As shown in Figure 1B, the series-shunt topology supporting five LEDs requires only two driver circuits, LED Driver 1 and LED Driver 2. The series-shunt topology shown in Figure 1B includes LED shunts for individual control of each LED. A shunt is placed for each LED function, and as a result, each LED function can be controlled independently by activating the shunt using a control system connected to each shunt. As shown, V in The LED is connected to LED driver 1, which supplies power to LED string 1. LED driver 1 supplies power to a first LED (LED function 1) and a second LED (LED function 2). LED function 1 is also connected to a first LED dimming shunt, which shunts the power passing through the LED, allowing it to controllly dim or brighten LED function 1. As shown in Figure 1B, LED string 1 also includes LED function 2 connected to a second LED dimming shunt on LED string 1. By activating each shunt, the control system can control the brightness of either the first or second LED in LED string 1, and only a single driver is required to provide power and LED activation to LED string 1.

[0029] As shown in Figure 1B, the LED driver 2 is V in It is connected and configured to drive a set of three LEDs (LED functions 1, 2, and 3). Each of the three LEDs is connected to an individual shunt circuit that can be used to dim or brighten each LED without affecting the other LED functions in the same series.

[0030] To operate each shunt, the control system can turn the shunt off (disconnect) it, thereby allowing current to flow through the LED for that function, and thereby lighting up the LED. When the shunt for an LED function is on, current may be shunted around the LED for that function, so the LED may not turn on because the power is bypassing it. Alternatively, the shunt can be used to dim the LED rather than completely turn it off.

[0031] To dim the LEDs, each shunt can be modulated at a frequency high enough to avoid significant flicker, but low enough so that switching losses are minimal. For example, a shunt can be modulated to function at a frequency of approximately 200 Hz. Alternatively, depending on design constraints, shunts can be modulated to function at frequencies of approximately 100, 120, 130, 144 Hz, or above 200 Hz. An LED driver supplying power to each string of LEDs can maintain a constant current through the series, and therefore the current through any given LED function can be controlled by its associated shunt. Thus, shunts can drive multiple LED functions from the same LED driver while maintaining complete control over the relative brightness of each LED function. Shunts can be useful because they can be configured to use very little PCB space and can be relatively less complex compared to other electrical components such as LED drivers and boost converters.

[0032] Figure 1C is a timing diagram showing the exemplary voltage levels of LED functions 1, 2, 3, 4, and 5 in Figure 1B and the corresponding voltage levels that can be seen on two LED strings, with reference to the exemplary series-shunt topology shown in Figure 1B. LED functions 1 and 2 are in series and constitute LED string 1, and LED functions 3, 4, and 5 are in series and constitute LED string 2. Figure 1C also shows how different LED functions can be multiplexed to avoid overvoltage conditions in any LED string or LED function. For example, LED function 3 could be a daytime running lamp and LED function 5 could be a low-beam wide light. Since daytime running lights are on during the day and low-beam wide lights are on in the dark, these lights are never used simultaneously. Thus, the exemplary time multiplexing shown in Figure 1C shows how LED function 3 can function as a daytime running lamp and be turned on and activated only when LED function 5 as a low-beam wide light is off, and vice versa.

[0033] In another example, LED function 1 and LED function 2 can function as a second daytime running lamp and a third daytime running lamp, respectively. Thus, the exemplary time multiplexing shown in Figure 1C demonstrates how LED function 1, as the second daytime running lamp, is on only when LED function 2, as the third daytime running lamp, is off, and vice versa. These examples demonstrate how time multiplexing and / or interleaving of LED driver channels enables additional LED functions without increasing the forward voltage of the entire LED string.

[0034] Figures 2A and 2B illustrate examples of changing current flow through a series-shunt topology induced by shunts. By altering the current flow, various combinations of LED functions that may be used in specific situations can be enabled. For example, the shunt activation of the high-beam LEDs shown in Figure 2A can reduce the risk to oncoming vehicles by avoiding the activation of the high-beam LED function for nighttime driving. In another example, Figure 2B shows a combination of activated LED functions that may include only daytime running lights (DRLs) for daytime driving. As shown in Figure 2B, LED driver 1 is shunted to bypass the low-beam spot LED, low-beam wide LED, and high-beam LED, connecting only to the DRL 1 LED function that is to be activated. Similarly, LED driver 2 is connected to DRL 2 and DRL 3 so that all three DRL systems are activated, as shown in Figure 2B. Figures 2A and 2B also illustrate how diodes and shunts can be used to power the turn signals from either LED driver.

[0035] The depictions in Figures 2A and 2B can reflect all LED functions activated by LED Driver 1 and LED Driver 2, but not all LED functions need to be activated at the same moment. Figures 2A and 2B show exemplary modes of LED drivers that can activate one or more LED functions at a time, along with alternating and / or multiplexed signals to each of the associated LED functions.

[0036] The series-shunt topology described herein can use time multiplexing to share a single LED driver among multiple LED functions. Time multiplexing can be used because the shunt allows for individual control of different LED functions for interleaving and multiplexing the LED functions in time. Hysteresis LED drivers can suffer from poor electrical efficiency when there is a large difference between the input voltage to the LED driver and the output voltage from the LED driver. 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.

[0037] The reduction in input-output voltage difference can be attributed to the time multiplexing of LED functions driven by the same LED driver. For example, LED driver 1 in Figure 2A can drive DRL 1 and low beam wide because the maximum LED driver voltage does not include both low beam wide and DRL 1 simultaneously. The LED driver uses time multiplexing to drive the DRL 1 and low beam wide LED functions at different times. Similarly, DRL 2 and DRL 3 in Figure 2B are never turned on at the same time, and therefore LED driver 2 can drive both DRL 2 and DRL 3 because they never contribute to the maximum LED driver voltage simultaneously. This improvement in electrical efficiency and / or reduction in power consumption allows the boost converter used in a series-shrink topology to be physically smaller than the boost converter in other topologies. It should be understood that a series-shrink topology can be implemented using any commercially available LED driver.

[0038] In some implementations, LED matrix control systems result in large and expensive ECUs that are inefficient and can suffer large power / current surges affecting upstream components. In some implementations, the LED matrix control method generally synchronizes the start times of all pixels within a single LED bank. As used herein, “pixel” may be an individual LED. A pixel may also be part of an LED bank containing multiple individual LEDs, each of which may be individually powered to provide a specific light pattern within the LED bank. By synchronizing the start times of all pixels within a single LED bank, all pixels are turned on simultaneously and turned off simultaneously as needed to achieve the desired brightness. This results in maximum power / current being consumed from upstream components in a short time. To accommodate the surge, upstream components (e.g., wires, high-side drivers, etc.) must be sized to accommodate the power consumption, and the LED matrix module must be divided into banks of LEDs with a dedicated LED driver for each bank. Furthermore, more electrical inefficiencies exist due to the higher input / output voltage difference. This leads to each LED driver controlling a small portion of the LEDs. This design inefficiently utilizes LED drivers and requires multiple LED drivers to drive the matrix. This control method can enable fewer components, higher system electrical, component, and space efficiency, and lower system cost. This system and method can combine multiple banks to form channels. Instead of using one LED driver per bank, this method can use one LED driver per channel, thereby reducing the number of LED drivers required. This 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 the generation of surge currents by interleaving the activation periods of individual pixels.Embodiments of the system may be used to control any LED matrix, including but not limited to the series-shunt LED topology described above.

[0039] Figures 3A and 3B show exemplary LED matrix arrangements. Figure 3A shows individual pixels of a 28x4 matrix, each capable of operating within a lighting unit at a set brightness. The brightness of a given pixel may be determined by the currently activated LED function (e.g., high beam, low beam spot, or daytime running light). Another LED function may be flexed lighting, which is a function that can change the direction of the headlights when a vehicle is preparing to turn a corner, in the process of turning a corner, has completed turning a corner, or is adjusting to a curve in the road. In prior art implementations, flexed lighting was achieved mechanically by a motor rotating the headlight hardware so that the light beam is tilted toward the curve. In this embodiment, flexed lighting is achieved electronically by adjusting the pixel brightness to focus the light beam toward the curve. In some implementations, pixels facing the curve may have increased brightness, while pixels facing outward from the curve may become dimmer. In some implementations, flexed lighting can be achieved by creating interference patterns of light emitted by individual pixels based on the brightness of each individual pixel.

[0040] Figure 3B shows possible configurations of how the individual pixels in Figure 3A may be grouped into banks. As shown in Figure 3B, the LEDs can be grouped into nine banks of LED lights, each bank being individually controllable. In some embodiments, Figure 3A illustrates the utilization of each pixel, and Figure 3B illustrates the utilization of the banks. These nine banks may be further grouped into channels. To form a channel, a bank that consumes more power can be paired with a bank that consumes less power, such that the amount of power used never exceeds the maximum value of the associated LED driver driving power to the multiple banks grouped to form a single channel. In some implementations, one or more banks with low utilization are paired with one or more banks with high utilization, such that the power required by the bank does not exceed the maximum power that the LED driver can supply. Pixels within each bank can also be individually interleaved to smooth out large power / current surges that occur. In this control method, each channel can be driven by a single LED driver. Therefore, this control method can maximize the utilization of LED drivers while still implementing advanced functions such as refracted lighting, which require highly dynamic control of pixel brightness.

[0041] In some implementations, one or more banks with lower utilization rates are paired with one or more banks with higher utilization rates to ensure that the power required by the bank when performing any particular LED function does not exceed the maximum power that the LED driver can supply. Utilization rates can be measured by average power consumption, brightness, or the percentage of time that a threshold amount of current is typically consumed. Pixels within each bank can also be individually interleaved to smooth out large power / current surges that occur during any particular LED function.

[0042] Figures 4A and 4B show voltage levels within an LED matrix with interleaved pixel activation times. Figure 4A shows exemplary voltage measurements over time for three interleaved LED banks that can be controlled by a single LED driver configured so that the LED banks form a single channel. Interleaving does not require the LED banks to be activated simultaneously. Instead, each LED bank can be activated only when needed, allowing power surges to be distributed over time and thereby avoiding large surges. An interleaved LED matrix can support overlapping LED bank activations by grouping together banks that, even when activated simultaneously, do not consume more power than the driver can support.

[0043] Figure 4B shows exemplary voltage measurements of an LED channel over time. A channel can be formed by grouping at least two LED banks together. Each channel can be controlled by a dedicated LED driver. Interleaving allows the LED driver to be used for a longer period of time, in contrast to other methods that leave the LED driver idle for a relatively long period (at 0 voltage) between changes in LED function. As shown in the figure, interleaving can minimize peak channel voltages and prevent the system from exceeding the driver's maximum support voltage.

[0044] Figure 5 is a graph showing how pixel pairing can be optimized in the angular domain for bent illumination. As mentioned above, electronic bent illumination may require dynamic dimming and brightening of individual pixels. Figure 5 shows the bend angle and intensity of pixel A, pixel B, and their combined intensity. Pixel intensity may depend on the bend angle and may change as the bend angle changes. In some implementations, bent illumination can include beam patterns with bend angles of -10 to 5 degrees or -5 to 10 degrees, depending on whether the beam is emitted from the left or right side of the vehicle. In this example, -10 degrees could be -10 degrees relative to straight-shining light, and -10 degrees to the left or right. In some implementations, these bend angles can be configured to vary with a resolution of 0.1 degrees (allowing bend angles such as 0 degrees, 0.1 degrees, 0.2 degrees, 0.3 degrees, 0.4 degrees, etc.). Optimized pixel pairing can allow for adjustment of the intensity of each pixel during LED functionality while ensuring that the combined intensity of a pixel pair never exceeds 100%. Intensity can refer to the voltage, current, and / or power supplied to the pixel, or the brightness of the light emitted from the pixel. Pixel intensity can also be associated with the on-time of the pixel when pulse-width modulation is performed to power the pixel. For example, each pair of pixels cannot be supplied with a voltage, current, and / or power exceeding the maximum voltage, current, and / or power that can be supplied to a single pixel at any given time. In some implementations, each pair of pixels cannot emit light exceeding the maximum light that can be emitted by a single pixel. A pixel pair with 100% intensity at all angles can mean that the two pixels are perfectly matched, as any off-time of one pixel is filled by the on-time of the other.

[0045] As shown in Figure 5, pixels do not necessarily need to sum to 100% intensity for all angles, but the ideal sum should be as close to 100% as possible without exceeding 100%. By attempting to optimize 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, and others at positive angles. These pixels with maximum intensity at opposite angles may be paired together such that when one is dark, the other is bright. Paired pixels do not have to be adjacent to each other, nor do they have to be adjacent laterally. Alternatively, the intensity of a pixel pair can be optimized so that the sum is close to 200%, where 200% represents the maximum intensity of two pixels designed to be powered by an LED driver.

[0046] Pixel pairing can be optimized in the angular and temporal domains. For example, angular domain optimization pairs pixels based on their utilization across light bending angles. In another example, temporal domain optimization pairs pixels based on their utilization during temporal multiplexing. Pixel pairing can be optimized simultaneously in both the angular and temporal domains. Pixel pairing can also be optimized in the volt-second domain (as described herein).

[0047] Figure 6 is a graph showing volt-second analysis used to maximize the utilization of an LED driver. When multiplexing multiple LED functions, volt-second analysis (also known as Tetromino analysis) can be used to optimize the LED driver channel. Volt-second analysis allows us to see the maximum capability of the LED driver in terms of the area in volt-second units, represented by the rectangular portion in Figure 6. Using volt-second analysis, the LED driver (or controller of the LED driver) can determine which LED function to drive by examining the input voltage and the PWM of the input voltage. For example, an exemplary LED driver system with the volt-second analysis graph captured in Figure 6 drives the high-beam LED function when the input voltage is 30-50V and the PWM of the input voltage is 0-90%. The same exemplary LED driver system captured in Figure 6 drives the low-beam wide LED function when the input voltage is 10-30V and the PWM of the input voltage is 10-100%. Using volt-second analysis can result in a simpler design of the control scheme for 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 occupied. Increasing the LED driver output voltage can increase the total available volt-second area. Increasing the LED driver current can decrease the volt-second area required for each function, thereby enabling more functions per LED driver. Therefore, by adjusting the driver voltage and current, the utilization rate of the LED driver (e.g., the volt-second area of ​​the LED driver occupied by the LED functions) can be maximized.

[0048] Figures 7A and 7B show an exemplary flowchart illustrating a typical sequence of steps in optimizing pixel pairing. This flowchart helps ensure that pixels are paired as efficiently as possible for advanced features such as refracted lighting. This method also allows assigning a numerical value to each possible pair of pixels in a channel powered by an LED driver, where the value represents how well the pixels are paired.

[0049] Figure 7A illustrates an exemplary set of steps that can be described as angular domain optimization. Angular domain optimization describes the utilization rate of each pixel in the channel (for example, for advanced features such as refracted lighting) and uses that utilization rate to determine pixel pairing.

[0050] Figure 7B illustrates an exemplary set of steps that can be described as time-domain optimization. Time-domain optimization describes the utilization of pixels, banks, and / or channels, as well as their respective peak voltages or peak currents, over a period of time. Time-domain optimization can use multiplexing or interleaving techniques to ensure that the electrical system does not exceed peak voltages or peak currents (whether for pixels, banks, or channels) while providing the LEDs with the voltages and / or currents required for the target illumination or beam pattern and brightness.

[0051] The foregoing disclosure is not intended to limit the disclosure to the exact form or specific field of use disclosed. Therefore, various alternative implementations and / or modifications to the disclosure, whether expressly described or implied herein, are possible in light of the disclosure. Having described the forms of implementation of the disclosure in this manner, those skilled in the art will recognize that changes can be made in form and detail without departing from the scope of the disclosure. Therefore, the disclosure is limited only by the claims.

[0052] The aforementioned specification described the present disclosure with reference to specific implementation configurations. However, as those skilled in the art will understand, the various implementation configurations disclosed herein can be modified or implemented in various other ways without departing from the spirit and scope of the disclosure. Therefore, this description should be considered illustrative and is intended to teach those skilled in the art how to create and use various implementation configurations of the disclosed motor assemblies. It should be understood that the configurations of the disclosure shown and described herein should be interpreted as representative configurations. Elements, materials, processes, or steps shown and described representatively herein may be replaced with equivalent elements, materials, processes, or steps. Furthermore, certain features of the disclosure can be utilized independently of the use of other features, all of which will become apparent to those skilled in the art after benefiting from this description of the disclosure. Expressions such as “including,” “comprising,” “incorporating,” “consisting of,” “have,” and “is” used to describe and claim this disclosure are intended to be interpreted in a non-exclusive manner, that is, to allow for the existence of items, components, or elements not explicitly described. References to singular forms should be interpreted as relating to plural forms as well.

[0053] Furthermore, the various implementations disclosed herein should be interpreted in an illustrative and descriptive sense and not in any way as limiting the disclosure. All references to joining (e.g., mounting, fixing, joining, connecting, etc.) are used solely to aid the reader's understanding of the disclosure and do not imply any limitation with respect to the location, orientation, or use of the systems and / or methods disclosed herein. Accordingly, where there is a reference to joining, it should be interpreted broadly. Moreover, such references to joining do not necessarily mean that the two elements are directly connected to each other.

[0054] Furthermore, without limitation, all numerical terms such as “first,” “second,” “third,” “primary,” “secondary,” and “principal,” or any other order and / or numerical terms, should also be interpreted solely as identifiers to aid the reader’s understanding of the various elements, implementations, variations, and / or modifications of this disclosure, and in particular, no limitation in order or priority of any element, implementation, variation, and / or modification to another element, implementation, variation, and / or modification.

[0055] It should be understood that, depending on the specific application, one or more of the elements shown in the drawings / figures may also be implemented in a more separated or integrated manner, or in certain cases may be removed or rendered as non-functional. Furthermore, any signal hatches in the drawings / figures should be considered illustrative only and not limiting unless otherwise specified.

Claims

1. A system for controlling light-emitting diodes (LEDs) inside a vehicle, An electronic control unit (ECU) configured to control the current, voltage, or power to the LED driver circuit, The LED driver circuit is electrically connected to the first and second LEDs, A first shunt is connected to the ECU and configured to control the intensity of the first LED in order to control the first LED function, The system includes a second shunt connected to the ECU and configured to control the intensity of the second LED in order to control the second LED function, The aforementioned ECU is The first and second LEDs are paired such that the total intensity of the paired first and second LEDs is less than the maximum possible intensity of any individual LED powered by the LED driver circuit, and the total intensity and the maximum possible intensity are based on at least one of voltage, current, or power. Determine the threshold voltage-second value output by the LED driver circuit. A system configured such that the LED driver circuit outputs a volt-second value below the threshold value.

2. The system according to claim 1, wherein the first shunt is controlled using time-division multiplexing, angular-domain multiplexing, or volt-second analysis.

3. The system according to claim 1, wherein the second shunt is controlled using time-division multiplexing, angular-domain multiplexing, or volt-second analysis.

4. The system according to claim 1, wherein the ECU is configured to prevent the total power supplied to the first LED and the second LED from reaching a predetermined threshold.

5. The system according to any one of claims 1 to 4, wherein the ECU includes a plurality of profiles for illuminating a set of LEDs in a headlight assembly.

6. The system according to claim 5, wherein the plurality of profiles include profiles selected from high beam, low beam spot, low beam wide, daytime running light, and turn light profiles.

7. A method for controlling a light-emitting diode (LED) matrix inside a vehicle, The steps include receiving a signal to activate a set of LEDs electrically connected to an LED driver circuit in the vehicle, wherein the set of LEDs comprises a first LED and a second LED, A step of controlling a first shunt connected to the first LED to control the intensity of the first LED, The steps include controlling a second shunt connected to the second LED to control the intensity of the second LED, A step of pairing the first LED and the second LED such that the total intensity of the paired first LED and the second LED is less than the maximum possible intensity of any individual LED powered by the LED driver circuit, wherein the total intensity and the maximum possible intensity are based on at least one of voltage, current, or power; The steps include determining a threshold voltage-second value to be output by the LED driver circuit, The LED driver circuit outputs a voltage-second value that is below the threshold value. A method comprising the step of activating the LED driver circuit to supply power to the set of LEDs.

8. The method according to claim 7, further comprising the steps of monitoring the volt-seconds output by the LED driver circuit and bypassing the first LED when the volt-seconds exceed the threshold.

9. The method according to claim 7, wherein the step of activating the LED driver circuit includes the step of reading an LED lighting profile and determining the intensity values ​​of the first LED and the second LED.

10. The method according to claim 9, wherein the LED lighting profile is selected from high beam, low beam spot, low beam wide, daytime running light, or turn signal.

11. The method according to claim 7, wherein the step of controlling the first shunt includes time-division multiplexing, angular-domain multiplexing, or volt-second analysis of the first shunt.

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