Modular headlamp LED driver messaging system

Abstract

Various embodiments of this disclosure relate to a modular headlight LED driver messaging system. This disclosure describes a technique for controlling an LED lighting system using a circuit that includes communication, control, and LED driver circuitry specific to a limited number of lighting functions. This circuitry can communicate via a standard communication bus protocol and includes feedback, protection, and sensing circuitry to monitor lighting functions and LED performance. The circuitry can be small enough to be included as part of a lighting assembly (such as a vehicle headlight assembly). When compared to other techniques, the included feedback and monitoring circuitry may physically shut off the driven LEDs, thereby simplifying wiring. The configuration process for the circuitry can further simplify wiring connections and reduce the development and manufacturing costs of lighting systems that can use the circuitry. Limiting the lighting function of each circuitry can improve thermal management by distributing the thermal load.

Description

Technical Field

[0001] This disclosure relates to light-emitting diode (LED) lighting systems. Background Technology

[0002] Modern vehicle systems can use smart LED solutions to replace bulbs and high-intensity discharge (HID) lamps for front, interior, and rear lighting. Additionally, many industrial LED applications—such as architectural LED lighting, LED stripes, and even emergency lighting like exit signs—may benefit from cost-effective systems for controlling and powering this LED lighting. Summary of the Invention

[0003] Generally, this disclosure relates to techniques for controlling LED lighting systems using circuitry that includes communication circuitry, control circuitry, and LED driver circuitry for specific lighting functions specific to the number of wires. This circuitry can communicate via a two-wire communication bus protocol and may include feedback circuitry and sensing circuitry to monitor lighting functions and LED performance. Satellite circuits can be small enough to be included as part of a lighting assembly (such as a vehicle headlight assembly). In this disclosure, "satellite driver circuitry" may refer to driver circuitry used for a subset or portion of the available lighting functions. Compared to other techniques, the included feedback circuitry and sensing circuitry may physically shut off the driven LEDs, thereby simplifying wiring. Communication protocols and configuration procedures for satellite circuits can further simplify wiring connections and reduce the development and manufacturing costs of lighting systems that can use satellite circuits. Limiting the lighting function of each satellite circuit can improve thermal management by distributing the thermal load.

[0004] In one example, this disclosure describes a circuit configured to control a set of light-emitting diodes (LEDs) to perform a specified lighting function. The circuit includes: a communication circuit means configured to receive and interpret messages from a bus controller; a configuration memory; and an LED driver circuit configured to drive the set of LEDs to perform the specified lighting function, wherein the circuit operates the LED driver circuit to perform the specified lighting function based on whether the message includes an identifier for the specified lighting function of the circuit and information stored in the configuration memory.

[0005] In another example, this disclosure describes a system comprising: a bus controller; a collection of light-emitting diodes (LEDs); circuitry configured to communicate with the bus controller and drive the collection of LEDs to perform a lighting function, the circuitry including: a configuration memory; and LED driver circuitry configured to drive the collection of LEDs to perform the lighting function, wherein the circuitry operates the LED driver circuitry to perform the lighting function based on whether a message received from the bus controller includes an identifier for the lighting function of the circuitry, and information stored in the configuration memory.

[0006] In another example, this disclosure describes a method comprising: receiving a message from a bus controller via a communication bus by a circuit; determining whether the message includes a function identifier for a function performed by the circuit; and, in response to determining that the message includes a function identifier for a function performed by the circuit, driving an LED based on a set of: instructions included in the message from the bus controller, and a configuration of the circuit stored in a configuration memory of the circuit.

[0007] Details of one or more examples of this disclosure are set forth in the accompanying drawings and the following description. Other features, objects, and advantages of this disclosure will be apparent from the specification, drawings, and claims. Attached Figure Description

[0008] Figure 1 This is a block diagram illustrating an example LED lighting system according to one or more technologies of this disclosure, the example LED lighting system including a vehicle headlight device assembly with satellite circuitry.

[0009] Figure 2 This is a block diagram illustrating details of a satellite LED driver circuit according to one or more technologies disclosed herein.

[0010] Figure 3 This is a conceptual diagram illustrating an example message used with a system according to one or more technologies disclosed herein.

[0011] Figure 4 This is a block diagram showing an alternative example LED lighting system.

[0012] Figure 5 This is a flowchart illustrating an example operation of a lighting system according to one or more technologies disclosed herein. Detailed Implementation

[0013] Figure 1This is a block diagram illustrating an example LED lighting system according to one or more technologies of this disclosure, the example LED lighting system including a vehicle headlight assembly with satellite circuitry. The configuration of system 100 eliminates the need for an intermediate controller and the complex and costly connections between the intermediate controller and the headlight assembly, which can be used with other types of headlight assemblies. In addition to controlling and driving the vehicle headlight assembly, system 100 can also control other loads and other LED lighting. The description of this disclosure will focus on vehicle lighting, but the technologies of this disclosure can also be applied to other power supply applications, including lighting for buildings, outdoor lighting, security lighting, and non-lighting applications including motor drives.

[0014] Figure 1 Examples of system 100 depicted include: a body control module (BCM) 102, a headlight device assembly 110 (referred to as headlight 110), and other satellite drivers for loads other than headlight 110. System 100 can be installed on a vehicle (such as an automobile or similar vehicle) to control and drive various lighting and other functions. Some examples of vehicle lighting functions that can be performed by headlight 110 may include: high beam function, low beam function, daytime running light (DRL) function; turn indicator function, cornering light function, fog light function, position or driving light function, dynamic bending light function, control of pixel lights and matrix lights, and similar functions.

[0015] Headlight 110 may include one or more satellite driver circuits, switches, and an LED assembly to provide vehicle lighting functionality. An example of headlight 110 includes a satellite driver circuit A 112 (referred to as circuit A112) configured to operate an LED string 140. Headlight 110 also includes circuit B 114 that supplies power to LEDs 142. LEDs 142 may include one or more LEDs controlled by matrix manager 118. In other examples, headlight 110 may include more or fewer satellite driver circuits and LED assemblies. Vbat 150 may supply power to components of system 100. Vbat 150 may be implemented as a battery or some other power source.

[0016] As described above, in this disclosure, "satellite driver circuit" can refer to a driver circuit used for a subset or portion of the available lighting functions. Like satellite driver circuits A 112, C 120, and D 112, circuit B 114 can be configured to control a set of light-emitting diodes (LEDs) to perform a specified lighting function or a combination of lighting functions. For example, circuit B 114 can control and drive a turn signal function. In other examples, circuit B can control a combination of turn signals and daytime running lights, or a combination of other functions.

[0017] Circuit B 114 may include communication circuitry configured to receive and interpret messages from a bus controller (such as BCM 102). Circuit B 114 may also include configuration memory and LED driver circuitry configured to drive a set of LEDs 142 to perform a specified lighting function. Some examples of LED driver circuitry may include DC-DC converter circuitry, such as boost, buck, buck-boost, and other types of driver circuitry.

[0018] Configuration memory of circuit B 114 ( Figure 1 (Not shown) Information (not shown) can be stored to customize circuit B 114 for the arrangement of headlight 110. For example, circuit B 114 may be a satellite driver circuit configured to control turn signal functionality. Headlight 110 may include one or more LEDs and a string of LEDs for turn signal functionality. In other examples, different headlight assemblies may use different sets of LEDs with different power requirements, different duty cycle preferences, etc., that differ from the arrangement of headlight 110 to provide turn signal functionality. The configuration memory of circuit B 114 can customize circuit B 114 to operate turn signal functionality for any compatible headlight device assembly.

[0019] In operation, circuit B 114 can operate the LED driver circuit based on whether the message from BCM 102 includes an identifier for a specified lighting function or a function performed by circuit B 114, and information stored in the configuration register. Figure 1 (Not shown in the image) to perform the specified lighting function.

[0020] In the example of headlight 110, circuit B 114 provides power to matrix manager 118 to drive LED 142. Matrix manager 118 receives control commands from BCM 102 via communication bus 138. In some examples, circuit B 114 can provide power to LED 142 to provide a first lighting function at a first time and a second lighting function at a second time based on messages from BCM 102. For example, circuit B 114 can provide power for daytime running light function while BCM 102 configures matrix manager 118 to control a subset of LEDs of LED 142 performing the daytime running light function. The power provided by circuit B 114 can be set to a specified voltage, current, duty cycle, etc., as specified by the configuration memory of BCM 102 and circuit B 114. In some examples, BCM 102 can send a message to circuit B 114 that includes only a lighting function activation flag and LED brightness level. Specific details of the duty cycle and other settings can be determined by circuit B 114 based on the lighting function and configuration memory.

[0021] At the second time point, BCM 102 can send messages to circuit B 114 and matrix manager 118 to perform different functions (such as turn signals, fog lights, etc.). In some examples, the combination of matrix manager 118 and circuit B 114 can operate dynamic turn signal indicators, such as wiping or ripple effect turn signals.

[0022] In some examples, BCM 102 may communicate only with circuit B 114, without directly communicating with matrix manager 118. In some examples, circuit B 114 may include a second communication connection to matrix manager 118. Figure 1 (Not shown in the diagram), similar to communication link 139 described for circuit D 112. In other words, circuit B 114 can interpret messages from BCM 102 and communicate with matrix manager 118 to perform one or more lighting functions.

[0023] Circuit B 114 may receive power from Vbat 150. In some examples, circuit B 114 may receive power from Vbat 150 via switch 132. Switch 132 may be any type of switch, such as a metal-oxide-semiconductor field-effect transistor (MOSFET), and may be used for protection or otherwise to regulate the power supplied to circuit B 114. In some examples, circuit B 114 may also include a feedback function that can determine the operating state of one or more LEDs 142.

[0024] Similar to circuit B 114, circuits A 112, C 120, and D 122 may include communication circuitry configured to receive and interpret messages from a bus controller (such as BCM 102). Circuits A 112, C 120, and D 122 may also include configuration memory and LED driver circuitry configured to drive a set of LEDs to perform a specified lighting function. In some examples, each satellite driver circuit may be configured to perform a different lighting function than the others. For example, circuit A 112 may be configured for a high beam function. Circuit A 122 may receive power from Vbat 150. In some examples, circuit A 112 may receive power via switch 130, which is similar to switch 132 described above.

[0025] In some examples, the headlight 110 may also include a bypass switch 117. The bypass switch can be configured to disable one or more portions of the LED string 140 to perform a specified function. As a possible example, the bypass switch 117 may be controlled by a satellite driver A 112 to deactivate a portion of the LEDs 140 for low beam functionality and activate all LEDs 140 for high beam functionality. In other examples, the bypass switch 117 may be directly controlled by the BCM 102 (… Figure 1 (Not shown in the image) Receive messages. In this disclosure, the bypass switch 117 may also be referred to as a switch network.

[0026] Circuit C 120 can control lighting separate from headlight 110. For example, fog lights, reversing lights, or brake lights can be separate from the headlight assembly. Circuit C 120 can (and in some examples, via switch 134) receive power from Vbat 150. Circuit C 120 can cause the LED driver circuit within the circuit operating circuit C 120 to perform a specified lighting function based on a message from BCM 102, which includes an identifier for the specified lighting function for the circuit and information stored in the configuration memory. Similar to circuits A 112, B 114, and D 122, vehicle manufacturers or lighting component manufacturers can program the configuration memory of circuit C 120 based on, for example, the type of LEDs in LED set 144, the voltage characteristics and other characteristics of Vbat 150, the desired balance between light output and energy saving, etc. Figure 1 In the example, LED set 144 is a single LED, but in other examples it may include two or more LEDs.

[0027] The satellite driver circuit of this disclosure can also be configured to drive loads other than those used for lighting functions. For example, circuit D 122 can be configured to drive various other loads 124. Other loads 124 may include any of the following: an audible alarm, a display, a motor (such as driving a cooling fan to dissipate heat for thermal management of one or more components of system 100), a power supply for a second-stage linear current regulator of an LED driver, or a DC-DC LED driver. Although depicted as separate from the headlight device assembly 110, in other examples, other loads 124 may be included as part of the headlight device assembly 110, for example, configured to (e.g., when the vehicle is not moving) manage the temperature of circuits A 112 and B 114.

[0028] As described above, circuit D 122 can receive power from Vbat 150 via switch 136 and provide power to other loads 124 based on messages from BCM 102 and predefined configurations stored in the configuration memory of circuit D 122. In some examples, satellite driver circuitry (such as circuit D 122) may include connections (e.g., via communication link 139) for communicating with other loads 124.

[0029] In examples where the other load 124 is a motor, circuit D 122 can be implemented using a drive circuit (such as an H-bridge). In other words, when selecting a satellite driver circuit to drive the motor, the system designer can choose a satellite driver with a DC-DC driver circuit configured to effectively drive the motor, such as a DC-DC driver including an H-bridge controller and one or more bypass switches, rather than, for example, a buck-boost type driver. In this way, the technology of this disclosure includes a variety of satellite driver circuits to provide a modular approach to the system design of the vehicle lighting system depicted by system 100.

[0030] exist Figure 1 In the example, BCM 102 is configured as a body control module. However, in other examples, BCM 102 can be any type of control unit, such as an electronic control unit, which can be used as a bus controller to control one or more functions (e.g., those of the vehicle). BCM 102 may include one or more processors 104 operatively coupled to one or more memory devices 106. Figure 1 In this example, BCM 102 also includes communication circuitry 108. BCM 102 can monitor and control various aspects of vehicle operation. Some examples may include monitoring sensors indicating whether doors are closed, tire pressure, operation indicator lights, and communication with a secondary processor (such as an electronic control unit (ECU)). BCM 102 can operate in a master / slave configuration with satellite driver circuitry of system 100, where computation can be distributed between the BCM and LED drivers.

[0031] Examples of processors for processor 104 may include any one or more processors such as a microcontroller (MCU) (e.g., a computer on a single integrated circuit, including a processor core, memory, and programmable input / output peripherals), a microprocessor (μP) (e.g., a central processing unit (CPU) on a single integrated circuit (IC)), a controller, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a system-on-a-chip (SoC), or an equivalent discrete logic circuit device or integrated logic circuit device. The processor may be an integrated circuit device, i.e., an integrated processing circuit device, and this integrated processing circuit device may be implemented as a fixed hardware processing circuit device, a programmable processing circuit device, and / or a combination of both.

[0032] Communication circuitry 108 can be configured to communicate with satellite driver circuitry via communication bus 138. In some examples, communication circuitry 108 may include a Universal Asynchronous Receiver / Transmitter (UART). In some examples, communication circuitry 108 may operate using any one or more of the following: a Gigabit Multimedia Serial Link (GMSL) interface; a Controller Area Network (CAN) bus interface, UARToverCAN (Universal Asynchronous Receiver / Transmitter), a Controller Area Network-Flexible Data (CAN-FD) bus interface; an interface defined according to the FlexRay protocol; a link defined according to the Low Voltage Differential Signaling (LVDS) standard, such as FPD-Link, FlatLink, FPD-Link II, FPD-Link III, and OpenLDI, or a Very Large Controller Area Network (CAN-XL) bus interface. In an example of system 100, communication bus 138 may be a two-wire bus operating using CAN-FD or a similar two-wire protocol.

[0033] System 100 can control the vehicle's lighting functions based on vehicle operator input, sensor input, and other factors. For example, the vehicle operator can operate the controller to signal a left turn. BCM 102 can command the turn signal driver circuit (e.g., circuit B 114) to turn off the daytime running lights. BCM 102 can also command circuit B 114 and matrix manager 118 to activate the turn signal. BCM 102 can also command circuit C 120 to activate the turn lights at a specified brightness level based on the sensed level of ambient light around the vehicle. For each change, BCM 102 can send a message including a lighting function indicator via communication bus 138. Slave satellite driver circuits can respond to messages including lighting function indicators, and operate accordingly. In other words, circuit B 114 can ignore messages with turn function indicators on communication bus 138, but respond to messages including turn signal function indicators.

[0034] In other examples, BCM 102 can send messages in which a common identifier can be used to update the brightness levels of all functions. For example, a vehicle might enter a tunnel during the day. One or more sensors connected to BCM 102 (such as brightness sensors and cameras) can signal to BCM 102 that the vehicle has entered the tunnel. BCM 102 can send a message with a common identifier, causing all satellite driver circuitry to respond to the message and increase the brightness to a specified level. In other examples, BCM 102 can output a message with a common identifier for a subgroup of lighting functions, causing all lighting functions in that subgroup to respond to the message.

[0035] System 100 offers several advantages compared to other types of systems used to control lighting functions and other loads. The satellite driver circuitry of System 100 divides various lighting functions into modular, optional driver circuits. These satellite driver circuits provide a scalable solution for vehicle lighting and the control of other loads. Individual plug-and-play satellite driver circuits (each specific to a particular function and each with an LED driver) simplify and reduce the cost of lighting equipment components (such as headlights 110) compared to an intermediate electronic control unit that controls and drives all lighting functions. While each satellite driver circuit can be programmed to be configured for specific details, such driver circuits may not require the development, testing, and validation of dedicated software to control all aspects of all lighting functions of the vehicle. Each headlight equipment component, and changes to headlight equipment components, may require different dedicated software and associated development and validation costs. In some examples, it may be necessary to validate dedicated software to comply with the AUTOSAR (Automotive Open Systems Architecture) standard, which could add additional costs.

[0036] Furthermore, modules for satellite driver circuits that may not be specific to a particular headlight assembly can be used in other vehicles and lighting designs. The driver circuits can be built in high-volume, standard designs, which can reduce costs, improve reliability, and streamline the logistics of aftermarket parts. For example, satellite driver circuits according to one or more techniques of this disclosure can be implemented in several different models. A first model for operating turn signal functions, a second model for operating high beam functions, a third model for operating low beam functions, a fourth model for operating both high beam and low beam functions, etc. System designers can select appropriate driver circuit models, configure each driver circuit for the details of the lighting design, and achieve modular design in a way that reduces the need for extensive software development and testing. In some examples, headlight assembly designers can install and configure the satellite driver circuits before sending the headlight assembly to the vehicle assembly operation for final installation and configuration. In other words, the techniques of this disclosure can provide a selection of different satellite driver circuits to allow modular designs to drive a variety of different loads, where modules are selected based on desired design objectives.

[0037] Another advantage of satellite driver circuitry can include reducing the size, cost, and complexity of the interconnects between a single electronic control unit and the headlight device assembly. The interconnect for an intermediate dedicated electronic control unit that integrates all lighting, driver, and thermal management functions can include: output lines from each driver circuit to each LED or LED string in the headlight device assembly, sensor lines for monitoring LED performance, etc. The LED output lines can be sized to carry the required current over the distance between the dedicated electronic control unit and one or more headlight device assemblies.

[0038] Conversely, the satellite driver circuits according to this disclosure can be mounted close to a collection of LEDs to be driven by a particular satellite driver circuit. The power supply connection to this collection of LEDs can be short, and feedback between the LED driver circuits and the communication circuitry can be built into each satellite driver circuit. Each satellite driver circuit can be connected to a power bus provided by Vbat 150 and the communication bus 138. Compared to other technologies, the simplified connection arrangement of this disclosure can reduce costs, decrease hardware development effort, and improve reliability.

[0039] Other advantages may include simplified thermal management and reduced cost of heat dissipation structures that can be used by a single intermediate controller. For example, each satellite driver circuit can be mounted in a different location within the headlight assembly, which can distribute the heat generated by the LED driver circuitry within the satellite driver circuitry.

[0040] Figure 2This is a block diagram illustrating details of a satellite LED driver circuit according to one or more technologies of this disclosure. The satellite driver circuit 200 (referred to simply as circuit 200) is as described above regarding... Figure 1 Examples of circuits A 112, B 114, C 120, and D 122 are described and may have similar functions and characteristics. For example, circuit 200 may be configured to control an array of LEDs to perform a specified lighting function or some combination of lighting functions, or to provide power to another load (such as a motor).

[0041] exist Figure 2 In the example, circuit 200 includes processing circuitry 204, DC-DC driver circuitry 210, sensing circuitry 220, and communication circuitry 212. Circuit 200 can receive power from Vbat 250 and is also connected to a reference voltage Vref 252.

[0042] In the example of circuit 200, the configuration memory is an one-time programmable (OTP) memory 208. In other examples, the configuration memory may be reprogrammable and may be implemented by, for example, an EPROM or some other reprogrammable memory device. OTP memory 208 may store configuration information, such as the number and type of LEDs in the LED string 244. In some examples, the configuration information may also include predetermined settings for the selected brightness level, such as pulse width modulation information including the PWM frequency, the PWM duty cycle, and voltage and current settings for the selected brightness level. Other configuration information may include lighting function identifier values, LED power derating curves, other specified information for the vehicle or component where circuit 200 may be installed, and device-specific configurations specific to circuit 200, such as general purpose input / output (GPIO), safety status settings, etc.

[0043] In some examples, circuit 200 may include one or more protection functions. Examples of protection functions may include reverse polarity, LED short circuit, LED open-circuit load, LED power derating, and thermal shutdown. Sensing circuitry 220 may include one or more sensors, such as a temperature sensor, to detect errors or fault conditions within circuit 200 and having LED string 244. Configuration memory, i.e. Figure 2 The OTP memory 208 in the example may include threshold limits, operating ranges, and other settings to customize protection features for a specific application.

[0044] In some examples, the OTP memory 208 can receive configuration information from CAN terminals 214A and 241B via communication circuitry 212. Although in Figure 2The example is depicted as a CAN terminal, but the communication circuitry can communicate with any of the various communication protocols (such as those mentioned above). Figure 1 The aforementioned communication protocols work together.

[0045] The communication circuit device 212 can also be operatively coupled to the processing circuit device 204. (As mentioned above...) Figure 1 The communication circuit device 212 can receive messages from a bus controller (such as BCM 102). In some examples, the communication circuit device 212 can interpret the message from BCM 102 and determine that the message is for a lighting function not managed by circuit 200. The communication circuit device 212 and the processing circuit device 204 do not take any further action on the message.

[0046] In other examples, the communication circuitry can interpret messages received from BCM 102 and determine that the message is for a lighting function managed by circuitry 200. For example, the message may include an activation flag indicating whether the lighting function is turned on or off. The message may also include an indication of the brightness level of the LEDs in LED string 244. Processing circuitry 204 is operatively coupled to OTP memory 208, communication circuitry 212, and LED driver circuitry (i.e., DC-DC driver circuitry 210). Processing circuitry 204 can control DC-DC driver circuitry 210 based on messages received from communication circuitry 212 and information stored in OTP memory 208. For example, processing circuitry 204 can select a PWM frequency and duty cycle for a brightness level requested by BCM 102. Processing circuitry 204 can cause DC-DC driver circuitry 210 to provide a predetermined amount of current at the selected PWM frequency and duty cycle based on the number and type of LEDs in LED string 244 and other settings stored in OTP memory 208. (As stated above regarding...) Figure 1 The DC-DC driver circuit 210 can be implemented as various driver circuits, such as a buck converter, a boost converter, or other types of drivers. In some examples, the type of DC-DC driver 210 may depend on the expected operating environment, input voltage, expected load type, and other factors.

[0047] Similar to the above about Figure 1 The described circuit A 112, circuit 200 may include communication output terminals 216A and 216B. Circuit 200 can use the output communication terminals to control or otherwise communicate with other components in the lighting equipment assembly. For example, output terminals 216A and 216B can be connected via (e.g., using the methods described above regarding...) Figure 1The other loads 124 or matrix manager 118 described are connected to the component via a communication link. In other words, output terminals 216A and 216B can be configured to control one or more switches, allowing circuit 200 to drive a set of LEDs via one or more switches to perform a specified lighting function. In some examples, output terminals 216A and 216B can also communicate with one or more downstream secondary power supplies driven by DC-DC driver circuit 210. In some examples, communication circuitry 212 can receive messages from BCM 102 via CAN terminals 214A and 214B, which can travel through circuit 200 to another component. In other examples, communication circuitry 212 of circuit 200 can generate signals to control the operation of downstream components connected to output terminals 216A and 216B.

[0048] Regarding the above Figure 1 Similar to the described processor 104, the processing circuitry 204 can be implemented as any logic circuit, hardware, software, or combination including a microcontroller. However, compared to intermediate electronic control unit technology, the operation of the processing circuitry 204 can be considered a black box for the system designer. The above-mentioned implementation using circuitry 200... Figure 1 In one of the described lighting functions, the system designer only needs to provide configuration information to be stored in the OTP memory 208 to customize the circuitry 200 to control the LED string 244. Providing configuration information can have the advantage of reducing development time and cost compared to coding and testing custom software, for example, executed on a general-purpose microcontroller.

[0049] Figure 3 This is a conceptual diagram illustrating an example message used with a system according to one or more technologies based on this disclosure. (See above regarding...) Figure 1 As described, message frame 300 is one possible example of a message format that can be transmitted on the communication bus 138 between BCM 102 and satellite driver circuitry and other components of system 100. Message frame 300 may have a structure similar to that of CAN or CAN-FD message frames.

[0050] Message frame 300, also known as a data packet, may include Start of Frame (SOF) 301, Arbitration field 302, Header field 304, Data field 306, and Authentication field (in...). Figure 3 The example includes the Cyclic Redundancy Check (CRC) field 308, the Acknowledgment (ACK) field 310, and the End of Frame (EOF) delimiter 312.

[0051] Arbitration field 302 may include function identifier 314. (As mentioned above...) Figure 1 and Figure 2As described, the function identifiers can enable the communication circuitry of the satellite driver circuitry to ignore or respond to messages. In some examples, the messaging system of this disclosure can directly address each individual lighting function. For example, Figure 1 The BCM 102 shown can output a message with a fog light function identifier on the communication bus. Satellite driver circuitry controlling the high beam function may ignore this message. However, satellite driver circuitry for the fog light function can respond to the message, for example, by turning it on or off, changing the shape of the lighting output, increasing or decreasing the brightness, etc. In other examples, the function identifier 314 can be a generic identifier that can be applied to all lighting functions or a subset of lighting functions. For example, a generic identifier could cause all satellite driver circuitry to increase or decrease the brightness level.

[0052] exist Figure 3 In the example, data field 306 includes data CRC 316, CID 318, counter field CNT 320, and master / slave frame 322. CRC 316 can be a second CRC, which the communication circuitry of the satellite driver circuit can use to check the integrity of the master / slave frame 322. The master / slave frame 322 may include a master frame sent from the bus controller to the satellite driver circuit. (As mentioned above...) Figure 1 and Figure 2 As described, the master frame may include activation indicators or markers to turn LEDs on or off, brightness levels, and other similar control signals. The master / slave frame 322 may also include slave frames sent from the satellite driver circuitry to the bus controller (e.g., BCM 102). Slave frames may include information (such as confirmation that the receiver has received the transmitted frame, status messages, alarm messages) or markers (such as the satellite driver circuitry detecting an on LED, overheating, etc.).

[0053] CID 318 can be used to check whether the data is applicable to the correct function identifier 314. In some examples, CID 318 may include a portion of function identifier 314 and the communication circuitry of the satellite driver circuit can compare CID 318 with function identifier 314 for verification.

[0054] CNT 320 may include a rolling counter maintained by the originator of message frame 300 (e.g., BCM 102), and the rolling counter in CNT 320 may be used to detect duplicate frames or detect lost frame reception. CNT 320 may be incremented after any transmission of data to the communication bus, and CNT 320 may be set to zero after any device reset.

[0055] CRC 308 can be used as a verification check for the integrity of all frames 300. ACK 310 can provide an acknowledgment to the bus controller, the acknowledgment message being sent by at least one satellite driver circuit or other component in the system (e.g., as mentioned above). Figure 1 The matrix manager 118 described receives the data. In response to the bus controller not receiving acknowledgment of the transmitted frame from any receiver on the bus (e.g., via the ACK 310 field), the bus controller can retry the same frame using the same CNT 320 value.

[0056] Figure 4 This is a block diagram illustrating an alternative example LED lighting system. Similar to the above regarding... Figure 1 The described systems 100 and 400 may also include a bus controller, a BCM 402, and a headlight device assembly, a headlight 430. However, compared to system 100, an example of system 400 includes an intermediate electronic control unit, an electronic control unit (ECU) 420.

[0057] BCM 402 may include one or more processors 404, memory 406, and communication unit 408. In the configuration of system 400, BCM 402 can send CAN or LIN commands to ECU 420 to control and retrieve the status of the LED lighting function of headlight 430. Microcontroller 424 on ECU 424 can decode these commands and then control LED driver 426 or other external components to perform the operations requested by BCM 402. In some examples, communication unit 38 may be included as part of microcontroller 424. In other examples, communication unit 428 may include circuitry, such as those described above. Figure 1 The described UART circuit device controlled by microcontroller 424.

[0058] System 400 may have drawbacks, such as requiring a dedicated ECU to act as the interpreter of BCM commands. A dedicated ECU may also require the development of OEM-specific AUTOSAR-compliant software, which increases development costs for headlight equipment components and end products (such as vehicles). Compared to the satellite driver circuitry of this disclosure, a dedicated ECU may require new software development, testing, validation, and certification for each different application and any changes to a specific vehicle, rather than a simple configuration update used by the satellite driver circuitry of this disclosure.

[0059] Another drawback might include a large connector 460 to connect the LED driver 426 to all the LEDs within the headlight 430. Figure 4In the example, headlight 430 may include LEDs 435 and 436, as well as one or more LED strings 432, 433, 438, and 440. Connector 460 may also include sensor connection 464 from headlight 430 to microcontroller 424. As a result, the wiring harness including all connections 460 and 464 can be large and implemented with the resulting high cost for wiring.

[0060] In some examples, concentrating all LED drivers 426 in one location may require expensive thermal management solutions to dissipate the heat generated by the LED drivers 426 and protect surrounding components of the vehicle or other products. For example, a dedicated metal housing may be used to manage the heat generated by the LED drivers 426.

[0061] Figure 5 This is a flowchart illustrating example operation of a lighting system according to one or more technologies of this disclosure. Unless otherwise stated, it will be interpreted according to... Figure 1 To describe Figure 5 The frame.

[0062] The satellite driver circuit (e.g., circuit B 114) can receive messages (90) from the bus controller (BCM 102) via communication bus 138. Circuit B 114 can determine whether the message from BCM 102 includes a function identifier (92) for a function performed by the circuit, such as low beam function, turn signal function, motor drive function, power supply to the secondary DC-DC converter, etc.

[0063] If the function identifier issued by the master matches the slave identifier, the slave (e.g., circuit B 114) can take action according to the master request frame. Otherwise, circuit B 114 can ignore the entire frame. In other words, in response to determining that the message from BCM 102 includes a function identifier for a lighting function executed by circuit B 114, circuit B 114 can drive the set of LEDs based on both the instructions included in the message from bus controller BCM 102 and the configuration of circuit B 114 stored in its configuration memory. For example, as described above regarding Figure 3 The configuration information described herein allows the specified brightness level in the main control section of the message frame to be correlated with a predetermined PWM frequency, PWM duty cycle, current level, etc., in order to be output to the LED array.

[0064] In one or more examples, the above functionality can be implemented in hardware, software, firmware, or any combination thereof. For example, the above regarding... Figure 1 and Figure 4The one or more processors 104 and 404 described can be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functionality can be stored on a tangible computer-readable storage medium (such as those described above). Figure 1 , Figure 2 and Figure 4 The memory 106, memory 206 and memory 406 described are executed by a processor or a hardware-based processing unit.

[0065] Instructions can be executed by one or more processors, such as one or more digital signal processors (DSPs), general-purpose microprocessors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other equivalent integrated or discrete logic circuit devices. Therefore, the terms "processor" and "processing circuit device" as used herein can refer to any of the foregoing structures or any other structure suitable for implementing the techniques described herein. Similarly, the techniques can be fully implemented in one or more circuit or logic elements.

[0066] The techniques disclosed herein can be implemented in a variety of devices or apparatuses, including wireless handheld devices, ICs, or collections of ICs (e.g., chip sets). Various components, modules, or units are described in this disclosure to emphasize functional aspects of a device configured to perform the disclosed techniques, but do not necessarily need to be implemented by different hardware units. Rather, as described above, various units can be combined in a hardware unit or provided by a collection of interoperable hardware units (including one or more processors described above).

[0067] The techniques disclosed herein can also be described in the following examples.

[0068] Example 1. A circuit configured to control a set of light-emitting diodes (LEDs) to perform a specified lighting function, the circuit comprising: a communication circuit means configured to receive and interpret messages from a bus controller; a configuration memory; and an LED driver circuit configured to drive the set of LEDs to perform the specified lighting function, wherein the circuit operates the LED driver circuit to perform the specified lighting function based on whether the message includes an identifier for the specified lighting function of the circuit, and information stored in the configuration memory.

[0069] Example 2. Based on the circuit of Example 1, the message includes a lighting function activation flag and an LED brightness level.

[0070] Example 3. A circuit based on any combination of Examples 1-2, wherein the circuit is configured to perform one or more of the following specified lighting functions based on an identifier in a message: high beam function, low beam function, daytime running light (DRL) function; turn indicator function; and fog light function. Based on an activation flag in the received message.

[0071] Example 4. A circuit based on any combination of Examples 1-3, wherein the circuit is configured to perform one and only one of the following functions at a given time: high beam and low beam function or daytime running lights (DRL) and turn indicator function.

[0072] Example 5. A circuit based on any combination of Examples 1-4, wherein the configuration memory is configured to store information including the number of LEDs in the set of LEDs and the type of LEDs in the set of LEDs.

[0073] Example 6. A circuit based on any combination of Examples 1-5, wherein the configuration memory is an one-time programmable (OTP) memory. The LED driver circuit includes: a DC-DC driver circuit, and a sensing circuit device configured to monitor the performance of a collection of LEDs.

[0074] Example 7. A circuit according to any combination of Examples 1-6, wherein the LED driver circuit includes: a DC-DC driver circuit; and a sensing circuit device configured to monitor the performance of a set of LEDs.

[0075] Example 8. A circuit based on any combination of Examples 1-7, wherein the bus controller is configured to communicate according to a two-wire bus communication standard selected from one of the following: Controller Area Network (CAN), Controller Area Network-Flexible Data (CAN-FD), UART over CAN (Universal Asynchronous Receiver / Transmitter), or Local Interconnect Network (LIN).

[0076] Example 9. A circuit according to any combination of Examples 1-8, further comprising a communication output terminal configured to control one or more switches, wherein the circuit is configured to drive a set of LEDs via one or more switches to perform a specified lighting function.

[0077] Example 10. A circuit according to any combination of Examples 1-9 further includes a communication output terminal configured to communicate with one or more secondary power supplies.

[0078] Example 11. The circuit according to any combination of Examples 1-10 further includes a processing circuit means operatively coupled to the configuration memory, the communication circuit means, and the LED driver circuit, wherein the processing circuit means is configured to control the LED driver circuit based on messages received by the communication circuit means and information stored in the configuration memory.

[0079] Example 12. A system comprising: a bus controller; a collection of light-emitting diodes (LEDs); circuitry configured to communicate with the bus controller and drive the collection of LEDs to perform a lighting function, the circuitry including: a configuration memory; and LED driver circuitry configured to drive the collection of LEDs to perform the lighting function, wherein the circuitry operates the LED driver to perform the lighting function based on whether a message received from the bus controller includes an identifier for the lighting function of the circuitry, and information stored in the configuration memory.

[0080] Example 13. The system according to Example 12, wherein the set of LEDs is a first set of LEDs and the circuit is a first circuit, the system further includes a second set of LEDs and a second circuit, wherein the first circuit is configured to perform one or more of the following lighting functions based on an identifier in a received message: high beam function, low beam function, daytime running light (DRL) function, turn indicator function, and fog light function, and the second circuit is configured to perform a lighting function that is different from the lighting function performed by the first circuit.

[0081] Example 14. A system based on any combination of Examples 12-13, wherein the bus controller is configured to synchronize and resynchronize the first and second circuits.

[0082] Example 15. A system based on any combination of Examples 12-14, wherein the circuit is configured to perform one and only one of the following functions at a given time: high beam and low beam function or daytime running lights (DRL) and turn indicator function.

[0083] Example 16. A system based on any combination of Examples 12-15, wherein the configuration memory is an one-time programmable (OTP) memory and the configuration memory is configured to store information about the number of LEDs included in the set of LEDs and the type of LEDs in the set of LEDs.

[0084] Example 17. A system based on any combination of Examples 12-16, wherein a two-wire bus communication standard is selected from one of the following: Controller Area Network (CAN), Controller Area Network-Flexible Data (CAN-FD), UART over CAN (Universal Asynchronous Receiver / Transmitter), or Local Interconnect Network (LIN).

[0085] Example 18. A system based on any combination of Examples 12-17 further includes a switching network, wherein the circuitry is configured to drive a set of LEDs via the switching network.

[0086] Example 19. A system based on any combination of Examples 12-18, where the switch network is a matrix manager.

[0087] Example 20. A system based on any combination of Examples 12-19, wherein a set of LEDs is configured to be used as a swipe-type turn indicator.

[0088] Example 21. A system according to any combination of Examples 12-20, wherein the circuitry further includes a processing circuitry means operatively coupled to the configuration memory and the LED driver circuitry, wherein the processing circuitry means is configured to control the LED driver circuitry based on messages received from the main controller and information stored in the configuration memory.

[0089] Example 22. A method comprising: receiving a message from a bus controller via a communication bus by a circuit; determining whether the message includes a function identifier for a function performed by the circuit; and, in response to determining that the message includes a function identifier for a function performed by the circuit, driving an LED based on a set of instructions included in the message from the bus controller and a configuration of the circuit stored in a configuration memory of the circuit.

[0090] Example 23. According to the method of Example 22, the message includes a lighting function activation flag and an LED brightness level.

[0091] Example 24. The method according to any combination of Examples 22-23 further includes: receiving a request for information from a bus controller by the circuit; determining the state of one or more LEDs in the set of LEDs by the circuit; and sending a message to the bus controller by the circuit including the state of one or more LEDs.

[0092] Example 25. A method based on any combination of Examples 22-24, wherein the state includes one or more of the following: whether one or more LEDs are lit or off; the brightness level of one or more LEDs; whether one or more LEDs have malfunctioned.

[0093] Various examples of this disclosure have been described. These and other examples are within the scope of the appended claims.

Claims

1. A circuit configured to control a set of light-emitting diodes (LEDs) to perform a specified lighting function, the circuit comprising: A communication circuit device is configured to receive and interpret messages from a bus controller, wherein the communication circuit device determines, based on the interpretation of the messages, whether the lighting function addressed by the messages should be managed by the circuit. Configure the memory; as well as An LED driver circuit is configured to drive the set of LEDs to perform the specified lighting function, wherein When the lighting function should not be managed by the circuit, the circuit does not take any further action; and When the lighting function is to be managed by the circuit, the circuit operates the LED driver circuit to perform the specified lighting function based on the following: Does the message include an identifier for the specified lighting function of the circuit; and Information stored in the configuration memory.

2. The circuit according to claim 1, wherein the message includes a lighting function activation flag and an LED brightness level.

3. The circuit of claim 1, wherein the circuit is configured to perform one or more of the following specified lighting functions in response to an identifier matched in the message: high beam function, low beam function, daytime running light (DRL) function; turn indicator function; and fog light function.

4. The circuit of claim 1, wherein the circuit is configured to perform one and only one of the following functions at a given time: high beam and low beam function or daytime running light (DRL) and turn indicator function.

5. The circuit of claim 1, wherein the configuration memory is configured to store information including the number of LEDs in the set of LEDs and the type of LEDs in the set of LEDs.

6. The circuit of claim 1, wherein the configuration memory is an one-time programmable (OTP) memory.

7. The circuit according to claim 1, wherein the LED driver circuit comprises: DC-DC driver circuit; as well as A sensing circuit device is configured to monitor the performance of the assembly of LEDs.

8. The circuit of claim 1, wherein the bus controller is configured to communicate according to a two-wire bus communication standard selected from one of the following: Controller Area Network (CAN), Controller Area Network-Flexible Data (CAN-FD), UARToverCAN (Universal Asynchronous Receiver / Transmitter), or Local Interconnect Network (LIN).

9. The circuit of claim 1, further comprising a communication output terminal configured to control one or more switches, wherein the circuit is configured to drive the set of LEDs via the one or more switches to perform the specified lighting function.

10. The circuit of claim 1 further includes a communication output terminal configured to communicate with one or more secondary power supplies.

11. The circuit of claim 1, further comprising a processing circuitry operatively coupled to the configuration memory, the communication circuitry, and the LED driver circuitry, wherein the processing circuitry is configured to control the LED driver circuitry based on the message received by the communication circuitry and information stored in the configuration memory.

12. A system comprising: Bus controller; An array of light-emitting diodes (LEDs); The circuit includes a communication circuit device configured to communicate with the bus controller to receive and interpret messages from the bus controller, wherein the communication circuit device determines, based on the interpretation of the messages, whether a lighting function addressed by the messages should be managed by the circuit. When the lighting function should not be managed by the circuit, the circuit does not take any further action; and When the lighting function is to be managed by the circuit, the circuit drives the set of LEDs to perform the lighting function. The circuit includes: Configure the memory; as well as An LED driver circuit is configured to drive the set of LEDs to perform the lighting function, wherein The circuit operates the LED driver circuit to perform the lighting function based on the following: Does the message received from the bus controller include an identifier for the lighting function of the circuit? Information stored in the configuration memory.

13. The system of claim 12, wherein the set of LEDs is a first set of LEDs and the circuit is a first circuit, the system further comprising a second set of LEDs and a second circuit. The first circuit is configured to perform one or more of the following lighting functions based on the identifier in the received message: high beam function, low beam function; daytime running light (DRL) function; turn indicator function; and fog light function. The second circuit is configured to perform a lighting function that is different from the lighting function performed by the first circuit.

14. The system of claim 13, wherein the bus controller is configured to synchronize and resynchronize the first circuit and the second circuit.

15. The system of claim 12, wherein the circuit is configured to perform one and only one of the following functions at a given time: high beam and low beam function or daytime running lights (DRL) and turn indicator function.

16. The system of claim 12, wherein the configuration memory is an one-time programmable (OTP) memory, and the configuration memory is configured to store information including the number of LEDs in the set of LEDs and the type of LEDs in the set of LEDs.

17. The system of claim 12, wherein the bus controller is configured to communicate according to a two-wire bus communication standard selected from one of the following: Controller Area Network (CAN), Controller Area Network-Flexible Data (CAN-FD), UARToverCAN (Universal Asynchronous Receiver / Transmitter), or Local Interconnect Network (LIN).

18. The system of claim 12, further comprising a switching network, wherein the circuitry is configured to control part of the set of LEDs via the switching network.

19. The system of claim 18, wherein the switch network is a matrix manager.

20. The system of claim 18, wherein the set of LEDs is configured to serve as a swipe-type turn indicator.

21. The system of claim 12, wherein the circuitry further comprises a processing circuitry means operatively coupled to the configuration memory and the LED driver circuitry, wherein the processing circuitry means is configured to control the LED driver circuitry based on the message received from the bus controller and information stored in the configuration memory.

22. A method comprising: The communication circuitry of the circuit receives and interprets messages from the bus controller via a communication bus, wherein the communication circuitry determines, based on the interpretation of the messages, whether the lighting function addressed by the messages should be managed by the circuitry. When the lighting function should not be managed by the circuit, the circuit does not take any further action; When the lighting function should be managed by the circuit, the circuit determines whether the message includes a function identifier for the function performed by the circuit. In response to determining that the message includes a function identifier for a function performed by the circuit, the set of LEDs driven is based on: Instructions included in the message from the bus controller; as well as The configuration of the circuit is stored in the configuration memory of the circuit.

23. The method of claim 22, wherein the message includes a lighting function activation flag and an LED brightness level.

Images