A through-type tail lamp driving circuit

Abstract

The utility model relates to car lamp control technical field, concretely relates to a kind of through type tail lamp drive circuit. Including input end circuit, MCU module, DCDC module, LDO module, LIN module, left side LED drive unit, right side LED drive unit. Left and right share input end circuit, DCDC module, LDO module, MCU module and so on device to reduce cost, while using the mode of "position lamp hard wire+LIN mixed wake", meet the prerequisite of automobile tail lamp animation requirement, static current requirement, heat requirement, while protecting vehicle body relay and promoting the stability of circuit wake, make circuit more stable.

Description

Technical Field

[0001] This utility model relates to the field of vehicle lighting control technology, specifically to a through-type taillight drive circuit. Background Technology

[0002] like Figure 1 As shown, for continuous taillights, in existing technologies, the drive circuits on both the left and right sides require: input circuits, DC-DC converters, LDOs, MCUs, linear chips, and LED loads. This results in the following technical defects in existing taillight drive circuits: (1) High overall cost; (2) It is easy for the left and right sides to be out of sync; (3) Because the left and right PCBs are mirror images and the left and right wiring harnesses are common, the PCB traces are not completely consistent when drawing the PCB, which greatly increases the difficulty of EMC rectification. Utility Model Content

[0003] The technical problem to be solved by this invention is to reduce costs while meeting customer requirements (animation requirements, static current requirements) and heat requirements.

[0004] Therefore, this utility model provides a through-type taillight drive circuit to reduce hardware costs while meeting the requirements of automotive taillight animation, static current, and heat requirements, and at the same time protect the vehicle body relay and improve the stability of circuit wake-up.

[0005] The technical solution adopted by this utility model to solve its technical problem is: A through-type taillight driving circuit includes an input terminal circuit, an MCU module (microprocessor), a DCDC module (DC-DC converter), an LDO module (low dropout linear regulator), a LIN module, a left LED driving unit, and a right LED driving unit. The input circuit serves as a power input, receiving dual inputs from the TAIL power input (dedicated power supply for taillights) and the KL30 power input (constant vehicle power). The TAIL power input powers the left and right LED driver units via a DC-DC module, while the KL30 power input powers the LIN module. The KL30 power input is connected to the MCU module via an LDO module to power it. The LIN module serves as the vehicle communication unit and interacts with the MCU module.

[0006] Both the LIN module and the TAIL power input (hardwired) are used to wake up the KL30 power input.

[0007] The left LED driver unit, the right LED driver unit, and the MCU module interact via a proprietary CAN module.

[0008] By adopting the above technical solution, the left and right sides share input terminal circuits, DC-DC converters, LDOs, MCUs and other components to reduce costs. At the same time, the "hard-wired + LIN hybrid wake-up" method is used to meet the static current requirements, making the circuit more stable.

[0009] Furthermore, when the signal line at the TAIL power input (hard wire) is used to wake up the KL30 power input, the current at the input terminal of the TAIL power input is appropriately increased to protect the relay of the vehicle body.

[0010] It should be noted that in existing technologies, the TAIL power input hard wire is usually only used as a power line to power the taillights, or to transmit control signals through an additional signal line. If the current is too small during signal transmission, it may cause the body relay to malfunction, while if it is too large, it will burn out the relay. Therefore, this solution protects the body relay by appropriately increasing the current.

[0011] Furthermore, the TAIL power input regulates the input current through the position light input circuit, thereby protecting the vehicle body relay.

[0012] Furthermore, the left LED driving unit and the right LED driving unit are connected in parallel and then connected to the DC-DC module; Meanwhile, both the left LED driving unit and the right LED driving unit include a linear driving chip and an LED load. The DC-DC module is connected to the linear driving chip, which drives the LED load.

[0013] Furthermore, the proprietary CAN module is contained in both the left and right LED driver units. While the MCU module communicates and interacts with the linear driver chip in the left proprietary CAN module, it also communicates with the right proprietary CAN module through the left proprietary CAN module.

[0014] Compared to traditional independent left and right control (which is prone to synchronization deviation due to signal delay), the high communication speed and low transmission latency of the CAN bus ensure that the control commands from the MCU module (such as animation frame data and brightness adjustment signals) are synchronously transmitted to the private CAN modules on both sides. These private CAN modules then transmit the commands to the corresponding linear drive chips, ultimately achieving millisecond-level synchronous response of the LED loads on both sides. This avoids the "left and right animation asynchrony" display problem seen in through-type taillights. Furthermore, compared to the left-side core circuit (including the MCU module, DCDC module, LIN module, etc.), the right-side circuit has fewer components, simpler wiring, and no complex signal interference sources. When EMC (electromagnetic compatibility) testing fails, the source of interference can be quickly located (mostly concentrated in the left-side core circuit), eliminating the need to check redundant components on the right side one by one, significantly reducing the EMC rectification cycle and difficulty.

[0015] Furthermore, each set of the private CAN modules is powered by a corresponding linear drive chip, and the two communicate with each other.

[0016] The above setup, compared to existing technologies, shortens the physical trace length between the two components, reducing electromagnetic interference (such as radiation interference from surrounding circuits and crosstalk between wires) during long-distance signal transmission. Simultaneously, the CAN bus itself possesses differential signal transmission characteristics, offering strong anti-interference capabilities. Combined with the short-link design, this further enhances the stability of the "CAN module-linear driver chip" communication, preventing control command loss or status feedback errors due to interference. The CAN module is powered by the linear driver chip, which only operates after the circuit is woken up (KL30 power input is turned on). When not woken up, neither the linear driver chip nor the proprietary CAN module consumes power, avoiding the problem of traditional independently powered CAN modules "still consuming power in static conditions," thus helping the overall circuit meet customer requirements for quiescent current control.

[0017] The beneficial effects of this utility model are: 1. While meeting customer design requirements, it can reduce costs and improve market competitiveness; the left and right sides share input circuits, DC-DC modules, LDO modules, MCU modules and other components, which can meet customer requirements for lighting fixtures and eliminate multiple redundant drive modules, thereby reducing costs; 2. To meet the customer's requirements for quiescent current control, this design directly connects the power supply of the LIN chip to the KL30 module, LDO module, MCU module, DCDC module, and private CAN module, all of which are connected to the back side of the wake-up circuit, thus meeting the customer's requirements for quiescent current.

[0018] 3. TAIL power input position lamp wire power wire (hard wire): When using signal wire, appropriately increasing the current at the input end can protect the vehicle body relay. 4. The KL30 power input wake-up uses either a hard-wired position light or a LIN module to make the circuit more stable; 5. The power supply for the internal proprietary CAN module has been changed from an external LDO module to an internal LDO power supply for the linear drive chip, which can further reduce costs; 6. Reduced Design Difficulty in Lighting Fixtures. Modern automotive designs are becoming increasingly minimalist, squeezing out the space available for internal components and thus increasing the demands on component placement. This design eliminates most components, significantly reducing the PCB area and consequently lowering the overall design complexity of the lighting fixture.

[0019] 7. When the EMC test fails, the right-side drive only has a private CAN module, a linear drive chip, and an LED load, which reduces the difficulty of EMC rectification. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Figure 1 It is a circuit block diagram of existing technology; Figure 2 This is the circuit block diagram of this utility model; Figure 3 This is the position lamp input circuit diagram of this utility model; Figure 4 This is the input circuit diagram of the KL30 utility model; Figure 5 This is the LIN input circuit diagram of this utility model.

[0022] In the diagram: 1. TAIL power input; 2. KL30 power input; 3. MCU module; 4. DCDC module; 5. LDO module; 6. LIN module; 7. Proprietary CAN module; 8. Linear driver chip; 9. LED load. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the present invention, and therefore only show the components relevant to the present invention.

[0024] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] Reference Figure 2 A through-type taillight driving circuit includes a TAIL power input 1, a KL30 power input 2, an MCU module 3, a DCDC module 4, an LDO module 5, a LIN module 6, a left LED driving unit, and a right LED driving unit; both the left LED driving unit and the right LED driving unit are composed of a linear driving chip 8, an LED load 9, and a proprietary CAN module 7.

[0027] TAIL power input 1 serves as the dedicated power source for the taillights, while KL30 power input 2 provides constant power for the vehicle. TAIL power input 1 is connected to MCU module 3 via a detection circuit, which monitors the status of the connected TAIL power supply, including parameters such as voltage and current, and feeds this information back to MCU module 3. KL30 power input 2 is connected to DC-DC module 4 and LDO module 5 via an input circuit to provide power. LDO module 5 is then connected to MCU module 3 to provide power. The input circuit performs power protection and signal conditioning on the input KL30 power supply before distributing it to DC-DC module 4 and LDO module 5. MCU module 3 communicates with the linear driver chip 8 in the left LED driver unit, and also communicates with the private CAN module 7 in the right LED driver unit via the private CAN module 7 in the left LED driver unit, and with the linear driver chip 8 on the right side via the private CAN module 7 in the right LED driver unit. The KL30 power input 2 is also connected to the LIN module 6 to supply power. The LIN module 6, as an on-board communication unit, establishes a signal connection with the vehicle (body controller) through the vehicle body LIN bus. At the same time, the LIN module 6 establishes a point-to-point signal connection with the MCU module 3 through the signal output pin of its LIN chip U1 to achieve communication.

[0028] The power supply terminal (Vlin) of the LIN chip U1 is connected to the power input 2 of the KL30, which is independent of the power supply of the MCU module 3 (provided by the LDO module 5) to ensure controllable quiescent current. The LIN module 6 establishes a wake-up signal connection between its LIN chip U1 output terminal and the input terminal loop.

[0029] TAIL power input 1 provides a position line (also a hard wire, essentially a power line, but actually used as a signal line) to the vehicle body. Its connection to the input circuit is achieved through the position light input circuit.

[0030] Reference Figure 3In one embodiment, the position light input circuit includes capacitors PC1, PC2, and PC3, a TVS diode PT1, a reverse protection diode PD1, a transistor PQ1, and resistors PR1, PR2, PR3, PR4, PR5, PR6, PR7, PR8, PR9, PR10, PR11, and PR12. The filter circuit composed of TVS diode PT1, capacitors PC1 and PC2, the reverse protection diode PD1, resistors PR4-PR12, resistors PR1-PR3, capacitor PC3, and transistor PQ1 are used to provide position light signals to the MCU module 3 and to provide a PL+ signal to wake up KL30, forming a hardware wake-up method. The LIN module 6 and the TAIL power input 1 hardwire are both used to wake up the KL30 power input 2. Resistors PR4-PR12 add approximately 100mA of current to the position light line to protect the vehicle body relay.

[0031] Specifically: TVS diode PT1 is connected to the TAIL power input at one end and grounded (GND) at the other end. Capacitors PC1 and PC2 are also connected to the TAIL power input at one end and grounded (GND) at the other end, forming a filter circuit to filter out noise from the TAIL power input. Anti-reverse diode PD1 has its anode connected to the TAIL power input (after filtering by PC1 and PC2), and its cathode connected to the input of a resistor network consisting of resistors PR4, PR5, PR6, PR7, PR8, PR9, and PR10 connected in parallel. The output of the resistor network is connected to one end of resistor PR1. The other end of resistor PR1 is connected to one end of capacitor PC3 and one end of resistor PR2, and also to the base of transistor PQ1. The other ends of resistor PR2 and capacitor PC3 are both grounded (GND). The emitter of transistor PQ1 is grounded (GND), and its collector is connected to one end of resistor PR3, simultaneously outputting the POW_Sig signal. The other end of resistor PR3 is connected to the +5V power supply output from LDO module 5.

[0032] Reference Figure 4 The input circuit includes diode D3, resistors R5, R6, R7, and R18, and capacitors C9, C10, C11, and C12. Within this input circuit is a sub-circuit responsible for power supply processing and wake-up control of the KL30 power input 2. Specifically, the vehicle LIN bus signal passes through diode D3, resistor R18, and capacitor C12 to the LIN chip U1 (model TLIN1021A). The LIN chip U1 outputs an INH voltage for KL30 wake-up and outputs LIN_RXD and LIN_TXD to the MCU for message transmission. The power supply Vlin for the LIN chip U1 is provided by KL30 power input 2. Specifically: Resistor R5 is connected at one end to the +5V power input of LDO module 5, and at the other end to the RXD pin and LIN_RXD signal of LIN chip U1 (model TLIN1021A); Resistor R6 is connected at one end to the WAKE pin of LIN chip U1, and at the other end to ground (GND); Resistor R7 is connected at one end to the TXD pin and LIN_TXD signal of LIN chip U1, and at the other end to the +5V power supply; Resistor R18 is connected to the LIN pin of LIN chip U1; Capacitors C9, C10, and C11 are each connected at one end to KL30 power input 2 and the VSUP pin of LIN chip U1, and at the other end to GND, forming a filter circuit to filter out noise from KL30 power input 2; Capacitor C12 is connected at one end to the output of resistor R18, and at the other end to ground (GND), used for filtering and stabilizing the voltage of the vehicle body LIN bus signal; Diode D3 has its anode connected to the output of resistor R18 and its cathode grounded (GND), used for filtering the vehicle body LIN bus signal. Bus signals are clamped to prevent reverse voltage from damaging the circuit.

[0033] Reference Figure 5In one embodiment, the input circuit diagram of LIN module 6 includes TVS transistor T1, capacitors C1, C2, C3, C4, C5, C6, C7, C8, MOSFET Q1, MOSFET Q2, diode D1, diode D2, resistors R1, R2, R3, R4, transistor Q3, and inductor L1. The KL30 power input 2 passes through a filter circuit consisting of TVS transistor T1, capacitors C1 and C2; an anti-reverse circuit consisting of MOSFET Q1, diode D1, resistor R1, and capacitor C3; a switching circuit consisting of MOSFET Q2, resistors R2, R3, R4, capacitor C8, transistor Q3, and diode D2, where the input terminal of diode D2 is connected to the TAIL power input 1PL+ signal and the INH pin of LIN chip U1, respectively, for the KL30 wake-up function. When not woken up, DC-DC module 4, LDO module 5, MCU module 3, and linear drive chip 8 do not work, which can meet the customer's requirements for static current; and a π filter circuit consisting of capacitors C4~C7 and inductor L1. After passing through the π filter circuit, the DC-DC module 4 is powered. The output voltage of the DC-DC module C powers the linear drive chips 8 on the left and right sides, and the linear drive chips 8 drive the LED load 9. The input of the LDO module 5 is provided by the power input 2 of the KL30, and it outputs +5V power to power the MCU module 3 (S9KEAZ128AMLH). The MCU module 3 outputs UART communication to drive the linear drive chip 8 on the left (TPS929120) and the private CAN module 7 (TCAN1044) for communication on the right. The power supply of the private CAN module 7 is provided by the linear drive chip 8. In this way, one LDO module 5 can be omitted on the right side, and the synchronization of the communication between the MCU module 3 and the linear drive chips 8 on the left and right sides can be guaranteed.

[0034] Specifically: TVS diode T1 is connected at one end to power input 2 of KL30 and grounded (GND) at the other end to suppress transient high-voltage pulses from the input power supply; capacitors C1 and C2 are both connected at one end to power input 2 of KL30 and grounded (GND) at the other end, forming a filter circuit to filter out noise from power input 2 of KL30; the source of MOSFET Q1 is connected to power input 2 of KL30, the drain is connected to one end of resistor R1 and the cathode of diode D1, and the gate is connected to the collector of transistor Q3; the anode of diode D1 is grounded (GND), and the cathode is connected to the drain of MOSFET Q1 and one end of resistor R1 for freewheeling protection of MOSFET Q1; the other end of resistor R1 is connected to one end of capacitor C3 and the MOSFET... The source of transistor Q2 is connected to capacitor C3. The other end of capacitor C3 is grounded (GND) for filtering and stabilizing the source voltage of transistor Q2. The drain of transistor Q2 is connected to one end of resistor R2 and one end of inductor L1, and the gate is connected to the other end of resistor R2. The other end of resistor R2 is connected to the drain of transistor Q2 for gate bias. Inductor L1 is connected to the power output terminal (VCC is connected to DC-DC module 4, and Vlin is connected to LIN chip U1) and one end of capacitors C4, C5, C6, and C7. One end of each of capacitors C4, C5, C6, and C7 is connected to +5V. The power supply output is connected to the ground (GND) at the other end, forming a multi-stage filter circuit to stabilize the +5V output voltage. The anode of diode D2 is connected to the INH signal, and the cathode is connected to one end of resistor R3. The other end of resistor R3 is connected to the base of transistor Q3 and one end of capacitor C8. One end of capacitor C8 is connected to the output terminal of resistor R3, and the other end is grounded (GND) for filtering and stabilizing the voltage at the base of transistor Q3. The emitter of transistor Q3 is grounded (GND). One end of resistor R4 is connected to the collector of transistor Q3, and the other end is grounded (GND) for collector biasing and current limiting of transistor Q3.

[0035] Detailed embodiments of the present invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely examples of the present invention, which can be implemented in various forms. Therefore, the specific structural and functional details disclosed herein should not be construed as limiting, but merely as the basis of the claims and as a representative basis for teaching those skilled in the art to employ the present invention differently with any suitable detailed structure contemplated. In particular, features presented and described in the individual dependent claims may be applied in combination, and any advantageous combinations of these claims are disclosed herein.

[0036] Furthermore, it is anticipated that structural elements can be generated by applying three-dimensional (3D) printing technology. Therefore, any reference to structural elements is intended to cover any computer-executable instructions that instruct a computer to generate such a structural element using 3D printing technology or similar computer-controlled manufacturing techniques. Additionally, any such reference to structural elements is also intended to cover computer-readable media carrying such computer-executable instructions.

[0037] Furthermore, the terms and phrases used herein are not intended to be restrictive, but rather to provide an understandable description of the present invention. As used herein, the term “a” or “an” is defined as one or more. As used herein, the term “multiple” is defined as two or more. As used herein, the term “another” is defined as at least a second or more. As used herein, the terms “comprising” and / or “having” are defined as including (i.e., open-ended language). As used herein, the term “connection” is defined as a link, although not necessarily a direct link.

[0038] The present invention, as thus described, can obviously be modified in many ways. These modifications should not be considered as a departure from the spirit and scope of the present invention, and all such modifications, which are obvious to those skilled in the art, are intended to be included within the scope of the appended claims.

[0039] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined by the scope of the claims.

Claims

1. A through-type taillight drive circuit, characterized in that, include Input circuit, MCU module (3), DC-DC module (4), LDO module (5), LIN module (6) and The left LED driving unit is powered by a set of DC-DC modules (4) through the input circuit. The input circuit of the right LED driving unit also supplies power to the left LED driving unit through the same set of DCDC modules (4); The left LED driver unit and the right LED driver unit are connected in parallel. The input circuit supplies power to the MCU module (3) through the LDO module (5), and also supplies power to the LIN module (6). The LIN module (6) interacts with the MCU module (3). The MCU module (3) controls both the left LED driving unit and the right LED driving unit simultaneously.

2. The through-type taillight drive circuit according to claim 1, characterized in that, The input circuit includes a TAIL power input (1) and a KL30 power input (2). The KL30 power input (2) is divided into two paths: one path supplies power to the left LED driver unit and the right LED driver unit through the DCDC module (4), and the other path supplies power to the LIN module (6); The TAIL power input (1) is connected to the MCU module (3) and is also used to hardwire wake up the KL30 power input (2); The LIN module (6) is also used to wake up the KL30 power input (2).

3. The through-type taillight driving circuit according to claim 2, characterized in that, Both the left LED driving unit and the right LED driving unit include a linear driving chip (8) and an LED load (9). The DC-DC module (4) is connected to the linear driving chip (8), and the linear driving chip (8) is used to drive the corresponding LED load (9).

4. The through-type taillight drive circuit according to claim 3, characterized in that, Both the left LED driving unit and the right LED driving unit also include a private CAN module (7). The MCU module (3) communicates with the private CAN module (7) in the right LED driving unit through the private CAN module (7) in the left LED driving unit.

5. The through-type taillight drive circuit according to claim 4, characterized in that, The private CAN module (7) in the right LED driver unit interacts with the linear driver chip (8).

6. The through-type taillight driving circuit according to claim 4, characterized in that, The MCU module (3) interacts with the private CAN module (7) in the left LED driver unit.

7. The through-type taillight driving circuit according to claim 4, characterized in that, The private CAN module (7) is powered by the corresponding linear drive chip (8).

8. The through-type taillight drive circuit according to any one of claims 1-7, characterized in that, The KL30 power input (2) is connected to the DCDC module (4) through the input terminal loop; The input circuit contains a sub-circuit responsible for power supply processing and wake-up control of the KL30 power input (2).

9. The through-type taillight driving circuit according to claim 8, characterized in that, The TAIL power input (1) is connected to the input circuit through the position light input circuit; Meanwhile, the output current in the position light input circuit is increased by a resistor network consisting of multiple sets of resistors connected in parallel.

10. The through-type taillight driving circuit according to claim 1, characterized in that, The TAIL power input (1) is connected to the MCU module (3) through a detection circuit.

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