A CAN bus headlamp universal controller
By using a CAN bus universal headlight controller, the problem of the difficulty in implementing a universal headlight controller in existing technologies has been solved. It enables flexible adaptation and intelligent management of headlight functions for various vehicle models, reducing development costs and time.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JHETECH
- Filing Date
- 2025-06-14
- Publication Date
- 2026-06-02
AI Technical Summary
Existing technologies make it difficult to achieve a universal headlight controller. Custom-designed controllers are expensive and cannot be adapted to various vehicle models. Simple switch control and hard-coding methods cannot support intelligent headlight functions and the energy consumption management requirements of electric vehicles.
The headlight universal controller adopts a CAN bus, including an input protection and anti-reverse module, a first-stage boost module, a second-stage buck module, a linear regulator module, a low-side control module, a first CAN transceiver, a second CAN transceiver, a main control chip, a motor drive module, etc. Through the coordinated work of these modules, universal control and data communication of headlight functions for various vehicle models can be achieved.
It enables universal control of headlight functions for various vehicle models, improves system flexibility and reliability, reduces development costs and time, and meets the requirements of intelligent headlight functions and energy consumption management for electric vehicles.
Smart Images
Figure CN224319568U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of electronic circuit control, and in particular to a CAN bus headlight universal controller. Background Technology
[0002] With the increasing prevalence of ADAS (Advanced Driver Assistance Systems) and autonomous driving technologies, automotive headlights are becoming increasingly diverse and intelligent. Headlight controllers need to support intelligent functions such as adaptive high beams (ADB), matrix LEDs, and laser headlights, making universal headlight controllers a market necessity. Simultaneously, electric vehicles have stringent energy management requirements, making efficient headlight control, such as dynamic dimming and low-power modes, essential. Furthermore, reducing development costs through standardized interfaces is also a crucial development direction for universal headlight controllers. Universal headlight controllers have broad application prospects in the future automotive market, but a balance needs to be struck between flexibility, compatibility with multiple vehicle models, and intelligent cost control.
[0003] In the past, various methods were used in the industry to achieve headlight control functions. One common approach was to design specific controllers for different car models and headlight types. This ensured perfect matching between the controller and the vehicle and headlights, but the development cost was high and it was difficult to adapt to constantly changing market demands. Another method was to use simple switch control. While this method was cheaper, it could only achieve basic headlight switching functions and could not meet the needs of modern cars for intelligent headlights. Some controllers implemented specific functions through hard coding, but this method lacked flexibility and made it difficult to expand and upgrade functionality.
[0004] The main drawback of existing technologies is that these conventional methods are difficult to implement universal headlight control. Specially designed controllers cannot be adapted to various vehicle models, resulting in high development costs and long development cycles; simple switch control and hard-coding methods cannot support intelligent headlight functions and complex algorithms, nor can they meet the energy consumption management requirements of electric vehicles. Utility Model Content
[0005] To improve the flexibility and adaptability of headlight control circuits, this application provides a CAN bus universal headlight controller.
[0006] The CAN bus headlight universal controller provided in this application adopts the following technical solution:
[0007] A universal headlight controller using a CAN bus includes an input protection and reverse polarity protection module, a first-stage boost converter, a second-stage buck converter, a linear regulator module, a low-side control module, a first CAN transceiver, a second CAN transceiver, a main control chip, a motor drive module, and the low-side control module. The input terminal of the input protection and reverse polarity protection module is connected to a power input terminal. The input terminal of the first-stage boost converter is electrically connected to the output terminal of the input protection and reverse polarity protection module. The first input terminal of the second-stage buck converter is electrically connected to the output terminal of the first-stage boost converter, and the second input terminal of the second-stage buck converter is electrically connected to the output terminal of the main control chip. The output terminal of the linear regulator module is electrically connected to the power supply terminals of the first CAN transceiver, the second CAN transceiver, and the main control chip. The first CAN transceiver is bidirectionally electrically connected to the main control chip, the second CAN transceiver is bidirectionally electrically connected to the main control chip, the motor drive module is electrically connected to the main control chip, and the low-side control module is electrically connected to the main control chip.
[0008] By adopting the above technical solution, universal control of headlight functions for various vehicle models is achieved. Input protection and reverse polarity protection modules ensure power input safety. The first-stage boost module and the second-stage buck module provide appropriate voltages for different loads. The linear voltage regulator module provides stable voltages for the first CAN transceiver, the second CAN transceiver, and the main control chip. The first and second CAN transceivers enable data communication between the vehicle system and the controller. The main control chip provides unified control of each circuit module. The motor drive module and the low-side control module work together with the main control chip to achieve corresponding functions.
[0009] Preferably, a filter is also included, and the input protection and anti-reverse module is electrically connected to the input terminal of the first-stage boost module through the filter.
[0010] By adopting the above technical solution, the filter can effectively filter noise and interference signals in the input power supply, reduce the impact of these interference signals on the first-stage boost module and other subsequent circuits, further improve the anti-interference capability and working stability of the entire controller, and ensure that the controller can still work normally in complex electromagnetic environments.
[0011] Preferably, the low-side control module includes a temperature detection submodule and a fan control submodule. The temperature detection submodule is a thermistor or a temperature sensor, and the fan control submodule includes a relay or MOSFET drive circuit.
[0012] By adopting the above technical solution, the low-side control module enables the main control chip to manage temperature detection and fan control in a unified manner. Through the temperature detection submodule, the temperature of the controller's internal components and related parts is monitored in real time. Based on the temperature signal, the main control chip can promptly control the fan control submodule to start or stop the fan for cooling, thereby achieving effective control of the controller's internal temperature, preventing malfunctions caused by overheating, and improving the controller's reliability and lifespan.
[0013] Preferably, the input protection and reverse connection protection module includes a TVS diode and a reverse connection protection element, wherein the reverse connection protection element is a diode or a MOSFET, and the TVS diode and the reverse connection protection element are connected in parallel at the input terminal of the input protection and reverse connection protection module.
[0014] By adopting the above technical solutions, TVS diodes can absorb high-energy surge voltages instantly, protecting the circuit from overvoltage impacts; the reverse connection protection components effectively prevent damage to the circuit caused by reverse power connection.
[0015] Preferably, the first-stage boost module is a BOOST constant voltage circuit, which includes an inductor, a capacitor, a diode, and a switching transistor. One end of the inductor is electrically connected to the output terminal of the input protection and reverse protection module. The switching transistor is connected in series between the other end of the inductor and the output terminal of the input protection and reverse protection module. The diode is connected in parallel with the inductor and its positive terminal faces the switching transistor. The capacitor is connected in parallel with the output terminal of the BOOST constant voltage circuit.
[0016] By adopting the above technical solution, the power supply voltage is increased to meet the needs of the subsequent buck circuit group; the inductor can store and release energy, the capacitor is used for filtering to make the output voltage more stable, the switching transistor has a fast switching speed and low loss, and the diode has a fast recovery speed and high withstand voltage, which makes the boost circuit perform better.
[0017] Preferably, the secondary step-down module includes at least two step-down branches, each of which includes a step-down chip and a filter element. The input terminal of the step-down branch is electrically connected to the output terminal of the primary step-up module, and the output terminal of the step-down branch is electrically connected to multiple headlight modules respectively.
[0018] By adopting the above technical solution, the two-stage step-down module includes multiple step-down branches, each corresponding to a different lighting module. It can perform precise step-down and filtering processing according to the different needs of each lighting module. This ensures that each lighting module receives the appropriate voltage and current for its operation, improving the brightness adjustment accuracy and operational stability of the lighting modules. It also facilitates independent control of different lighting modules by the main control chip, enhancing the controller's refined management capabilities of the headlight system and improving the overall performance and reliability of the headlight system.
[0019] Preferably, both the first CAN transceiver and the second CAN transceiver include a CAN transceiver chip and an isolation element. The isolation element is connected in series between the CAN transceiver chip and the main control chip, and the isolation element is an optocoupler or a magnetic coupler.
[0020] By adopting the above technical solution, the isolation elements in the first CAN transceiver and the second CAN transceiver can effectively isolate the signal between the CAN transceiver chip and the main control chip, prevent signal interference and noise transmission, and improve the quality and reliability of the communication signal.
[0021] Preferably, the linear voltage regulator module includes a voltage regulator chip and a filter capacitor. The input terminal of the voltage regulator chip is electrically connected to the output terminal of the input protection and reverse polarity protection module. The output terminal of the voltage regulator chip is electrically connected to the power supply terminals of the first CAN transceiver, the second CAN transceiver, and the main control chip through the filter capacitor.
[0022] By adopting the above technical solution, the voltage output of the input protection and anti-reverse module is stabilized to a suitable value by using a voltage regulator chip, and the filter capacitor further smooths the output voltage and reduces voltage fluctuations, which can provide a stable power supply to the first CAN transceiver, the second CAN transceiver and the main control chip.
[0023] In summary, this application includes at least one of the following beneficial technical effects:
[0024] 1. The TVS diode in the input protection and reverse connection protection module can quickly conduct when a sudden high voltage occurs in the power supply, clamping the excessive voltage within a safe range. The reverse connection protection component can prevent current from flowing in the opposite direction, protecting the downstream circuit and the entire circuit from damage, thus improving the reliability and stability of the system.
[0025] 2. The first-stage boost module increases the input voltage, and the second-stage buck module decreases the boosted voltage and outputs a voltage suitable for each load module. It can flexibly adjust the voltage according to the needs of different headlight loads, so that the headlights can function normally and extend their service life.
[0026] 3. The first and second CAN transceivers enable bidirectional data transmission between the vehicle system and the controller, forming a complete CAN communication network. This ensures smooth data interaction, improves communication reliability and anti-interference capabilities, and ensures the timeliness and accuracy of headlight control. Attached Figure Description
[0027] Figure 1 This is a schematic diagram of an embodiment of this application. Detailed Implementation
[0028] The following combination Figure 1 This application will be described in further detail.
[0029] This application discloses a CAN bus headlight universal controller.
[0030] Reference Figure 1 A CAN bus headlight universal controller includes an input protection and anti-reverse module, a filter, a first-stage boost module, a second-stage buck module, a linear regulator module, a low-side control module, a first CAN transceiver, a second CAN transceiver, a main control chip, and a motor drive module.
[0031] The power supply output terminal KL15 sequentially outputs starting voltage to multiple vehicle lighting modules through an input protection and reverse polarity protection module, a filter, a first-stage boost module, and a second-stage buck module. The input protection and reverse polarity protection module includes a TVS diode and a reverse polarity protection element. The TVS diode is typically selected for its fast response and precise clamping voltage; it can quickly conduct when a sudden surge in voltage occurs, clamping the excessive voltage within a safe range and protecting downstream circuitry from damage. At the moment of vehicle startup, the power supply output terminal KL15 may generate a sudden surge in voltage, which the TVS diode suppresses, protecting downstream modules. The reverse polarity protection element can be a diode or a MOSFET. When the power supply is reversed, the diode is cut off or the MOSFET does not conduct, preventing current from flowing in reverse and thus protecting the entire circuit. The output terminal of the input protection and reverse polarity protection module is set as a voltage output terminal Vin. In this embodiment, the output voltage range of the voltage output terminal Vin is 9~16V.
[0032] The filter can be configured as an RC filter network, filter capacitor, or other filter circuit to filter out noise and interference signals in the power supply, making the voltage input to the first-stage boost module purer and more stable, and ensuring the normal operation of subsequent circuits.
[0033] Specifically, the first-stage boost module is designed as a constant voltage circuit, comprising components such as inductors, capacitors, diodes, and switching transistors. The inductors are typically wire-wound inductors, possessing high inductance and low resistance, enabling them to store and release energy. Capacitors are used for filtering, making the output voltage more stable. Diodes are selected based on their fast recovery speed and high voltage rating. The switching transistor is usually a MOSFET, characterized by its fast switching speed and low power loss. When the switching transistor is on, the inductor stores energy; when the switching transistor is off, the inductor releases energy, charging the capacitor through the diodes, thereby increasing the voltage. The output voltage of this boost circuit is higher than the external power supply input voltage, for example, boosting the 9-16V external power supply to 50V to meet the requirements of the subsequent buck circuit group.
[0034] The output of the first-stage boost module is electrically connected to the first input of the second-stage buck module, and the output of the main control chip is electrically connected to the second input of the second-stage buck module. The second-stage buck module includes at least two independent buck branches, each containing a buck chip and related filtering components. The buck chip can be selected according to the requirements of different loads, and the filtering components are used to filter out ripple and noise generated during the bucking process. The outputs of each buck branch are respectively connected to the high beam module, low beam module, turn signal module, daytime running light module, cornering light module, and motor drive circuit, stepping down the 50V output from the boost circuit to provide a voltage suitable for each load module. The series and parallel connection method of different lights determines the output voltage of the buck circuit; for example, high beams may require a higher voltage, while daytime running lights require a lower voltage.
[0035] The output of the input protection and reverse polarity protection module is electrically connected to the power supply terminals of the first CAN transceiver, the second CAN transceiver, and the main control chip via a linear voltage regulator module. The linear voltage regulator module includes a voltage regulator chip and a filter capacitor. The voltage regulator chip stabilizes the input voltage at the set output voltage value; a low-dropout linear regulator is typically selected due to its high output voltage accuracy and low noise. The filter capacitor further smooths the output voltage and reduces voltage fluctuations. In this embodiment, the linear voltage regulator module stabilizes the output voltage of the input protection and reverse polarity protection module to 5V, supplying power to the main control chip, the first CAN transceiver, and the second transceiver.
[0036] Both the first and second CAN transceivers include CAN transceiver chips and isolation components. The CAN transceiver chip handles CAN data transmission and reception, while the isolation components provide electrical isolation, improving communication reliability and interference immunity. The first CAN transceiver receives CAN data from the vehicle's infotainment system and outputs it to the main control chip for parsing. The second CAN transceiver transmits the parsed CAN data from the main control chip to the circuits of different load-bearing functional modules, enabling or disabling various functions. The first and second CAN transceivers achieve bidirectional data transmission through the main control chip, forming a complete CAN communication network and ensuring smooth data interaction between the vehicle's infotainment system and the headlight controller.
[0037] The motor drive module may include an H-bridge drive circuit, which consists of four switching transistors, with the control terminals of multiple transistors connected to the PWM signal output terminal of the main control chip. When the main control chip outputs a PWM signal, the H-bridge drive circuit controls the rotation direction and speed of the motor according to the duty cycle and frequency of the PWM signal. By controlling the motor rotation angle, the headlight beam angle can be adjusted to meet different lighting needs.
[0038] The low-side control module includes a temperature detection submodule and a fan control submodule. The temperature detection module can use a thermistor or temperature sensor to detect the internal temperature of the lamp in real time and convert the temperature signal into an electrical signal output to the main control chip. The fan control submodule includes a relay or MOSFET driver circuit and is controlled by the logic signals of the main control chip. When the internal temperature of the lamp exceeds a set value, the main control chip sends a control signal, and the fan control module starts the fan to accelerate heat dissipation; when the temperature drops to a safe range, the fan stops operating.
[0039] The implementation principle of a universal headlight controller based on a CAN bus in this application is as follows: Through the collaborative work of multiple circuit modules, universal control of headlight functions for various vehicle models is achieved. Input protection and reverse polarity protection modules ensure the safety of the power input; boost and buck circuits provide suitable voltages for different loads; the CAN transceiver enables data communication between the vehicle system and the controller; and the main control chip provides unified control over all circuit modules. When a certain function is not needed for a particular vehicle model, the corresponding module can be removed, reducing production costs. Simultaneously, the controller's flexibility and maintainability are improved through the configuration interface and pluggable terminal block modules. Compared with existing technologies, this controller achieves a better balance between adapting to multiple vehicle models and intelligent cost control, significantly reducing development costs and development cycles, and possesses strong practicality and innovation.
[0040] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.
Claims
1. A universal headlight controller using a CAN bus, characterized in that: The system includes an input protection and reverse polarity protection module, a first-stage boost converter, a second-stage buck converter, a linear regulator module, a low-side control module, a first CAN transceiver, a second CAN transceiver, a main control chip, a motor drive module, and a low-side control module. The input terminal of the input protection and reverse polarity protection module is connected to the power input terminal. The input terminal of the first-stage boost converter is electrically connected to the output terminal of the input protection and reverse polarity protection module. The first input terminal of the second-stage buck converter is electrically connected to the output terminal of the first-stage boost converter, and the second input terminal of the second-stage buck converter is electrically connected to the output terminal of the main control chip. The output terminal of the linear regulator module is electrically connected to the power supply terminals of the first CAN transceiver, the second CAN transceiver, and the main control chip. The first CAN transceiver is bidirectionally electrically connected to the main control chip, the second CAN transceiver is bidirectionally electrically connected to the main control chip, the motor drive module is electrically connected to the main control chip, and the low-side control module is electrically connected to the main control chip.
2. The CAN bus headlight universal controller according to claim 1, characterized in that: It also includes a filter, through which the input protection and anti-reverse module is electrically connected to the input terminal of the first-stage boost module.
3. A universal headlight controller based on a CAN bus according to claim 1, characterized in that: The low-side control module includes a temperature detection submodule and a fan control submodule. The temperature detection submodule is a thermistor or a temperature sensor, and the fan control submodule includes a relay or MOSFET drive circuit.
4. A universal headlight controller based on a CAN bus according to claim 1, characterized in that: The input protection and reverse connection protection module includes a TVS diode and a reverse connection protection element. The reverse connection protection element is a diode or a MOSFET. The TVS diode and the reverse connection protection element are connected in parallel at the input terminal of the input protection and reverse connection protection module.
5. A universal headlight controller based on a CAN bus according to claim 1, characterized in that: The first-stage boost module is a BOOST constant voltage circuit, which includes an inductor, a capacitor, a diode, and a switching transistor. One end of the inductor is electrically connected to the output terminal of the input protection and reverse protection module. The switching transistor is connected in series between the other end of the inductor and the output terminal of the input protection and reverse protection module. The diode is connected in parallel with the inductor and its positive terminal faces the switching transistor. The capacitor is connected in parallel with the output terminal of the BOOST constant voltage circuit.
6. A universal headlight controller based on claim 1 or 5, characterized in that: The secondary step-down module includes at least two step-down branches, each of which includes a step-down chip and a filter element. The input terminal of the step-down branch is electrically connected to the output terminal of the primary step-up module, and the output terminal of the step-down branch is electrically connected to multiple headlight modules respectively.
7. A universal headlight controller based on a CAN bus according to claim 1, characterized in that: Both the first CAN transceiver and the second CAN transceiver include a CAN transceiver chip and an isolation element. The isolation element is connected in series between the CAN transceiver chip and the main control chip. The isolation element is an optocoupler or a magnetic coupler.
8. A universal headlight controller based on a CAN bus according to claim 1, characterized in that: The linear voltage regulator module includes a voltage regulator chip and a filter capacitor. The input terminal of the voltage regulator chip is electrically connected to the output terminal of the input protection and reverse polarity protection module. The output terminal of the voltage regulator chip is electrically connected to the power supply terminals of the first CAN transceiver, the second CAN transceiver, and the main control chip through the filter capacitor.