Vehicle lamp illumination circuit board
By integrating the turn signals, daytime running lights, and position lights into a single lighting circuit board, the structural complexity and high cost issues caused by the independent drive system of vehicle lighting modules are resolved, achieving the effects of simplified structure and reduced electromagnetic radiation.
Patent Information
- Application Number
- CN202423196224.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2025-11-18
- Estimated Expiration
- 2034-12-24
AI Technical Summary
The use of independent drive systems for turn signals, daytime running lights, and position lights in existing vehicles results in complex structures, high costs, and generally poor resistance to electromagnetic interference.
Design a vehicle lighting circuit board that integrates turn signals, daytime running lights, and position lights. The circuit board uses first and second circuit boards and a driver board to integrate turn signal, daytime running lights, and position light modules, and reduces electromagnetic interference through a boost control chip and a shield.
The design simplifies the headlight structure, reduces costs, improves assembly efficiency, and reduces the environmental impact of electromagnetic radiation.
Smart Images
Figure CN223559570U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of vehicle lighting technology, and in particular to a vehicle lighting circuit board. Background Technology
[0002] For driving safety, national standards have specified the light color and chromaticity characteristics of turn signals. However, daytime running lights are always on while the vehicle is in motion. If the daytime running lights are still on when the turn signals are turned on, the light color of the turn signals will not meet the national standard requirements. Furthermore, excessively bright daytime running lights will interfere with the brightness of the turn signals, making them difficult to detect, which does not meet vehicle regulations and safety requirements.
[0003] The existing technology uses three independent drive systems to drive the turn signals, daytime running lights and position lights respectively. However, this makes the lamp structure relatively complex, the cost high, and the electromagnetic interference generally poor. There is an urgent need for a lighting circuit board that can integrate the above-mentioned lighting modules. Utility Model Content
[0004] To address the problems of existing automotive lighting systems that use independent drive systems for various functions such as turn signals, daytime running lights, and position lights, resulting in complex structures, high costs, and limited electromagnetic interference resistance, this invention provides a vehicle lighting circuit board that integrates turn signals, daytime running lights, and position lights, simplifying the vehicle lighting structure, reducing costs, and improving assembly efficiency.
[0005] This utility model provides a vehicle lighting circuit board, including a first circuit board, a second circuit board, and a driver board. The first circuit board has a 4-pin driver input connector, and the second circuit board has a 3-pin driver input connector. The driver board has a power input terminal and a driver output terminal. The power input terminal is connected to the headlight wiring harness, and the driver output terminal is connected to the 4-pin driver input connector of the first circuit board and the 3-pin driver input connector of the second circuit board. A plurality of yellow-white bi-light LEDs are arranged on the first and second circuit boards. The driver board integrates a turn signal module, a daytime running light module, a position light module, and a boost control chip for controlling the yellow-white bi-light LEDs. Integrating turn signals, daytime running lights, and position lights simplifies the vehicle lighting structure and reduces costs.
[0006] Furthermore, the turn signal module, daytime running light module, and position light module are connected in parallel within an integrated circuit formed by a boost control chip. The boost chip has high conversion efficiency, effectively converting the input voltage into a stable output voltage and reducing energy loss.
[0007] Furthermore, a yellow light control module is also integrated into the integrated circuit to control the on / off state of the turn signal module.
[0008] Furthermore, a white light control module is also integrated into the integrated circuit to control the on / off state of the daytime running light module and the position light module.
[0009] Furthermore, the white light control module is also connected to a priority control module, which prioritizes the turn signal module when both the turn signal module and the daytime running light module are input simultaneously.
[0010] Furthermore, an analog dimming module is also integrated into the integrated circuit to adjust the brightness of the white light, with the daytime running light module having a higher brightness than the position module.
[0011] Furthermore, a differential mode filter module is also incorporated into the integrated circuit to reduce electromagnetic interference within the integrated circuit.
[0012] Furthermore, a turn signal fault feedback module is also integrated into the integrated circuit. The turn signal fault feedback module is connected to the FAULT pin of the boost control chip and is used to provide feedback on the open circuit or short circuit status of the turn signal module.
[0013] Furthermore, the integrated circuit also includes an inductor L2, a Schottky diode D2, and a MOSFET Q1. A shielding cover is provided on the driver board, covering the inductor L2, Schottky diode D2, and MOSFET Q1. The shielding cover is located at the switching node, where electromagnetic radiation is strong; a grounded shielding cover is used for isolation.
[0014] The beneficial effects of this utility model are as follows:
[0015] This utility model provides a vehicle lighting circuit board that integrates turn signal module, daytime running light module, and position light module, simplifying the vehicle lighting structure, reducing costs, and improving assembly efficiency. Furthermore, by setting a shielding cover outside the switching node inductor L2, Schottky diode D2, and MOSFET Q1, electromagnetic radiation can be isolated, reducing the impact of electromagnetic radiation on the surrounding environment and lowering circuit noise. Attached Figure Description
[0016] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the circuit board for the car lights;
[0018] Figure 2 This is a schematic diagram of the integrated circuit for a car headlight;
[0019] Figure 3 This is a circuit diagram of the yellow light control module, white light control module, priority control module, and turn signal fault feedback module;
[0020] In the diagram: 1. First circuit board; 11. Driver input 4-pin connector; 2. Second circuit board; 21. Driver input 3-pin connector; 3. Driver board; 31. Power input terminal; 32. Driver output terminal; 33. Shielding cover; 4. Yellow and white dual-beam LED; 5. Yellow light control module; 6. White light control module; 7. Priority control module; 8. Analog dimming module; 9. Differential mode filter module; 10. Turn signal fault feedback module. Detailed Implementation
[0021] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.
[0022] To simplify the structure of vehicle lights and reduce costs, a vehicle light illumination circuit board is designed, such as... Figure 1 As shown, the circuit includes a first circuit board 1, a second circuit board 2, and a driver board 3. The first circuit board 1 is provided with a 4-pin driver input connector 11, the second circuit board 2 is provided with a 3-pin driver input connector 21, and the driver board 3 is provided with a power input terminal 31 and a driver output terminal 32. The power input terminal 31 is connected to the headlight wiring harness, and the driver output terminal 32 is connected to the 4-pin driver input connector 11 of the first circuit board 1 and the 3-pin driver input connector 21 of the second circuit board 2. Sixteen yellow-white bi-xenon LEDs 4 are arranged on the first circuit board 1 and the second circuit board 2. The driver board 3 integrates a turn signal module, a daytime running light module, a position light module, and a boost control chip for controlling the yellow-white bi-xenon LEDs 4. The turn signal module, daytime running light module, and position light module are connected in parallel in an integrated circuit formed by the boost control chip U1.
[0023] The boost control chip U1 in this solution uses the BD18353, a 1-channel high-current LED controller manufactured by ROHM, specifically designed for automotive applications. The BD18353 features a built-in PWM generation circuit for freely setting the PWM dimming duty, a built-in high-side current detection amplifier for detecting LED current and outputting abnormal LED status to the FAULT terminal, and built-in dual-system analog dimming. It is compatible with the circuit system in this solution, which integrates various automotive lighting functions such as turn signals, daytime running lights, and position lights, simplifying the headlight structure, reducing costs, and improving assembly efficiency.
[0024] like Figure 2As shown, the switching nodes experience rapid voltage changes during switching. These voltage transitions can be considered sources of electromagnetic interference (EMI), radiating electromagnetic waves to the outside world through the power supply's internal wiring and PCB traces. The main EMI sources in a switching power supply include the PFC switching transistor, PFC boost diode, DC / DC switching transistor, DC / DC rectifier diode, freewheeling diode, PFC boost inductor, and DC / DC transformer. The electromagnetic radiation generated during operation may affect human health. The switching nodes in this integrated circuit include inductor L2, Schottky diode D2, and MOSFET Q1. To reduce the impact of electromagnetic radiation on human health, a shielding cover 33 is provided on the driver board 3. The shielding cover 33 covers inductor L2, Schottky diode D2, and MOSFET Q1, isolating electromagnetic radiation, reducing its impact on the surrounding environment, and lowering circuit noise.
[0025] like Figure 3 As shown, the integrated circuit also includes a yellow light control module 5, which controls the on / off state of the turn signal module. The yellow light signal input controls the MOSFET Q5; when a signal is received, Q5 conducts, and the yellow light illuminates.
[0026] The integrated circuit also includes a white light control module 6, which controls the on / off state of the daytime running light module and the position light module. The daytime running light or position light signal input controls Q4; when a signal is received, Q4 conducts, and the white light illuminates.
[0027] The white light control module 6 also includes a priority control module 7, which prioritizes the turn signal module when both the turn signal module and the daytime running light module are input simultaneously. When a yellow light signal is input simultaneously, MOSFET Q6 is turned on, and the gate voltage of MOSFET Q4, which is used to turn on the white light, is pulled to ground (GND). Q4 is turned off, and the white light cannot be lit. That is, when white and yellow light signals are input simultaneously, yellow light is lit first.
[0028] Specifically, the following situations will occur when the position lights, turn signals, and daytime running lights are illuminated: When the position lights are on and the turn signals and daytime running lights are off, the position lights are on; when the turn signals are on and the position lights and daytime running lights are off, the turn signals are on; when the daytime running lights are on and the position lights and turn signals are off, the daytime running lights are on; when the position lights and turn signals are on and the daytime running lights are off, the position lights are off, and the turn signals are on; when the position lights and daytime running lights are on and the turn signals are off, the position lights are dimly lit; when the turn signals and daytime running lights are on and the position lights are off, only the turn signals are on; when the position lights, turn signals, and daytime running lights are all on, only the turn signals are on.
[0029] The integrated circuit also incorporates an analog dimming module 8 for adjusting the brightness of the white light. The brightness of the daytime running light module is greater than that of the position light module. The analog dimming module 8 performs two-stage dimming. When the position light signal is input, MOSFET Q2 is turned on, and a voltage divider is formed through R15 and R16. The boost control chip U1 controls the load to output a low current, realizing the position light function with low white light brightness. When the turn light signal is input, MOSFET Q3 is turned on, the gate voltage of Q2 is pulled to ground (GND), and Q2 is turned off. At this time, resistor R16 is floating, and the DCDIM2 terminal (i.e., the analog dimming input pin) of the boost control chip U1 is directly connected to the VREF3 terminal (i.e., the reference voltage input pin) through R15. The boost control chip U1 controls the load to output a high current, realizing the turn light function with high white light brightness.
[0030] The integrated circuit also incorporates a turn signal fault feedback module 10, which is connected to the FAULT pin of the boost control chip U1 to provide feedback on open or short circuit conditions of the turn signal module. The FB port of the turn signal fault feedback module 10 is connected to the feedback pin of the entire lamp harness, and the FLT pin is connected to the FAULT pin of the boost control chip U1. When the load is working normally, the FAULT pin is high, MOSFET Q7 is off, transistor Q8 is also off, and the FB pin outputs a high level, indicating normal circuitry. When an open or short circuit occurs in the turn signal, the FLT pin is high, MOSFET Q7 is on, transistor Q8 is also on, and the FB pin outputs a low level, indicating abnormal circuitry.
[0031] The integrated circuit also incorporates a differential-mode filter module 9, composed of inductor L1 and capacitors C4, C5, C7, and C8, to reduce electromagnetic interference in the integrated circuit. Differential-mode filtering typically relies on the differential-mode inductor and capacitor. Inductor L1, through its inductive characteristics, provides impedance to differential-mode interference signals, thereby suppressing the propagation of differential-mode interference. Capacitors C4, C5, C7, and C8 are connected across the live and neutral wires of the power line, forming a capacitive path that bypasses differential-mode interference noise to the other end of the power line, achieving differential-mode filtering and reducing noise caused by the current returning along the loop on the power line.
[0032] The above description is illustrative only and not restrictive of this utility model. Those skilled in the art will understand that many modifications, variations or equivalents can be made without departing from the spirit and scope defined by the appended claims, and all such modifications, variations or equivalents will fall within the protection scope of this utility model.
Claims
1. A vehicle headlight illumination circuit board, characterized in that: The system includes a first circuit board (1), a second circuit board (2), and a driver board (3). The first circuit board (1) is provided with a 4-pin driver input connector (11), and the second circuit board (2) is provided with a 3-pin driver input connector (21). The driver board (3) is provided with a power input terminal (31) and a driver output terminal (32). The power input terminal (31) is connected to the headlight wiring harness, and the driver output terminal (32) is connected to the 4-pin driver input connector (11) of the first circuit board (1) and the 3-pin driver input connector (21) of the second circuit board (2). Several yellow-white bi-light LED beads (4) are arranged on the first circuit board (1) and the second circuit board (2). The driver board (3) integrates a turn signal module, a daytime running light module, a position light module, and a boost control chip for controlling the yellow-white bi-light LED beads (4).
2. The vehicle headlight illumination circuit board according to claim 1, characterized in that: The turn signal module, daytime running light module, and position light module are connected in parallel in an integrated circuit formed by a boost control chip.
3. The vehicle headlight illumination circuit board according to claim 2, characterized in that: The integrated circuit also includes a yellow light control module (5) for controlling the on / off state of the turn signal module.
4. The vehicle headlight illumination circuit board according to claim 2, characterized in that: The integrated circuit also includes a white light control module (6) for controlling the on / off state of the daytime running light module and the position light module.
5. A vehicle headlight illumination circuit board according to claim 4, characterized in that: The white light control module (6) is also connected to a priority control module (7), which is used to prioritize the turn signal module when the turn signal module and the daytime running light module are input at the same time.
6. A vehicle headlight illumination circuit board according to claim 2, characterized in that: The integrated circuit also includes an analog dimming module (8) for adjusting the brightness of the white light. The brightness of the daytime running light module is greater than that of the position module.
7. A vehicle headlight illumination circuit board according to claim 2, characterized in that: The integrated circuit also incorporates a differential mode filter module (9) to reduce electromagnetic interference in the integrated circuit.
8. A vehicle headlight illumination circuit board according to claim 2, characterized in that: The integrated circuit also includes a turn signal fault feedback module (10), which is connected to the FAULT pin of the boost control chip and is used to provide feedback on the open circuit or short circuit status of the turn signal module.
9. A vehicle headlight illumination circuit board according to claim 2, characterized in that: The integrated circuit also includes an inductor L2, a Schottky diode D2 and a MOSFET Q1. The driving board (3) is provided with a shield (33), which covers the inductor L2, the Schottky diode D2 and the MOSFET Q1.