Automotive LED indicator light driver circuit and device

Abstract

This invention relates to an automotive LED indicator light driving circuit and device. The driving circuit includes a main control module, a CAN decoding module, an interface module, a power supply module, and an LED light driving module. The power supply module includes three independent step-down modules: a first step-down module, a second step-down module, and a third step-down module. All three modules are connected to the interface module to obtain the power supply voltage from the vehicle's power supply. The first step-down module is connected to the CAN decoding module to convert the power supply voltage into a first operating voltage for the CAN decoding module. The second step-down module is connected to the main control module to convert the power supply voltage into a second operating voltage for the main control module. The third step-down module is connected to the LED indicator light to convert the power supply voltage into a third operating voltage for the LED indicator light. Through this method, this application enables effective hardware power supply isolation between the main control module, the CAN decoding module, and the LED indicator light.

Description

Automotive LED indicator light driver circuit and device Technical Field

[0001] This invention relates to the field of automotive indicator light driving technology, and in particular to an automotive LED indicator light driving circuit and device. Prior Technology

[0002] Note that with the development of intelligent and personalized automotive interiors, in-vehicle ambient lighting / indicator lights have become mainstream in-vehicle auxiliary electronic devices. As the core component of the in-vehicle lighting control circuit, the power supply system's voltage regulation topology design, power supply isolation, and ripple suppression capability directly determine the operational stability of the main control module and the lighting drive module, thereby affecting the control accuracy and operational reliability of the entire circuit.

[0003] In existing vehicle lighting control circuit power supply designs, the voltage regulation branch design is simple, generally using a cascaded step-down architecture of vehicle 12V power supply - 5V - 3.3V to power different functional modules in the control circuit, such as LED lights, MCU, and communication modules. That is, different functional modules share the same low-voltage power supply link, and there is a lack of effective hardware power supply isolation between functional modules. As a result, the current noise and electromagnetic interference generated by power devices such as LED lights will be conducted to the MCU and communication module through the shared power supply link, forming serious power supply crosstalk. At the same time, the ripple and voltage fluctuation of the front-end 5V branch will be directly conducted to the rear-end 3.3V branch. Combined with the ripple interference of the vehicle 12V power supply itself, it will also reduce the power supply accuracy of the rear-end 3.3V and increase the ripple of the rear-end 3.3V, which cannot meet the stable operation requirements of the MCU that requires 3.3V power supply.

[0004] The following detailed description of the features and advantages of this invention is sufficient to enable anyone skilled in the art to understand the technical content of this invention and implement it accordingly. Furthermore, based on the content disclosed in this specification, the scope of the patent application, and the drawings, anyone skilled in the art can easily understand the purpose and advantages of this invention. Summary of the Invention

[0005] The main purpose of this invention is to provide an automotive LED indicator driver circuit and device that enables effective hardware power supply isolation between the main control module, the CAN decoding module, and the LED indicator, effectively preventing the LED indicator from affecting other modules through the power supply link, while also avoiding the problem of the front-stage power supply branch affecting the power supply voltage of the rear stage, thereby improving the stability of circuit operation.

[0006] This application provides an automotive LED indicator light driver circuit, including a main control module, a CAN decoding module, an interface module, a power supply module, and an LED light driver module. The interface module is connected to the vehicle's power supply. The power supply module is connected to the interface module, main control module, CAN decoding module, and LED driver module to provide power. The CAN decoding module is connected to the vehicle's CAN bus via the interface module to receive vehicle status signals transmitted on the CAN bus. The main control module is connected to the CAN decoding module and generates LED driving signals based on the vehicle status signals and transmits them to the LED light driver module. The LED light driver module is connected to the LED indicator light via the interface module. The power supply module is connected to an interface module to control the LED indicator to light up according to the LED drive signal. The power supply module includes three independent step-down modules: a first step-down module, a second step-down module, and a third step-down module. The first step-down module, the second step-down module, and the third step-down module are all connected to the interface module to obtain the power supply voltage of the vehicle power supply. The first step-down module is connected to the CAN decoding module to convert the power supply voltage into the first operating voltage of the CAN decoding module. The second step-down module is connected to the main control module to convert the power supply voltage into the second operating voltage of the main control module. The third step-down module is connected to the LED indicator to convert the power supply voltage into the third operating voltage of the LED indicator.

[0007] This application also provides an automotive LED indicator device, including an LED indicator and the driving circuit described above; the LED indicator includes two outer rearview mirror indicator lights, two inner rearview mirror indicator lights, and a taillight. The two outer rearview mirror indicator lights are respectively disposed on the outer sides of the left and right rearview mirrors, and the two inner rearview mirror indicator lights are respectively disposed on the inner sides of the left and right rearview mirrors. The taillight is disposed on the exterior of the rear of the vehicle. The driving circuit is connected to the outer rearview mirror indicator lights, the inner rearview mirror indicator lights, and the taillight, and is used to drive the outer rearview mirror indicator lights on the same side as the door to illuminate when a door opening command is received; drive the rearview mirror indicator lights on the same side as the side vehicle to illuminate when a side vehicle approach warning signal is received; drive the taillight to illuminate in a first color when a smart driving mode activation command is received; drive the taillight to illuminate in a second color when a braking command is received; and drive the taillight to illuminate in a third color when a navigation mode selection command is received.

[0008] Beneficial technical effects: The power supply module of this application includes three independent step-down modules: a first step-down module, a second step-down module, and a third step-down module. The three step-down modules are used to power the CAN decoding module, the main control module, and the LED indicator, respectively. Thus, different modules use different power supply links to power them, which enables effective hardware power supply isolation between the main control module, the CAN decoding module, and the LED indicator. This effectively prevents the LED indicator from affecting other modules through the power supply link, and also avoids the problem of the front-end power supply branch affecting the power supply voltage of the subsequent stage, thereby improving the stability of circuit operation. Simple Explanation of the Diagram

[0009] Figure 1 is a schematic diagram of the structure of the automotive LED indicator driving circuit according to an embodiment of this application.

[0010] Figure 2 is a circuit diagram of the first step-down module according to an embodiment of this application.

[0011] Figure 3 is a circuit diagram of the second step-down module according to an embodiment of this application.

[0012] Figure 4 is a circuit diagram of a third step-down module according to an embodiment of this application.

[0013] Figure 5 is a circuit schematic diagram of the interface module according to an embodiment of this application.

[0014] Figure 6 is a circuit schematic diagram of the main control module according to an embodiment of this application.

[0015] Figure 7 is a circuit schematic diagram of the CAN decoding module according to an embodiment of this application.

[0016] Figure 8 is a circuit schematic diagram of the wireless communication module according to an embodiment of this application.

[0017] Figure 9 is a circuit schematic diagram of the LED driver module of this application.

[0018] Figure 10 is a circuit diagram of another third step-down module of this application. Implementation

[0019] The following specific examples illustrate the implementation of this invention. Those skilled in the art can easily understand the other advantages and effects of this invention from the content disclosed in this specification.

[0020] Referring to Figure 1, this application discloses an automotive LED indicator light driver circuit 100, which can be integrated into the vehicle control board. It includes a main control module 11, a CAN decoding module 12, an interface module 13, a power supply module 14, and an LED light driver module 15. The interface module 13 serves as the connection hub between the driver circuit 100 and external vehicle devices, connecting to the vehicle power supply. In this embodiment, the vehicle power supply is preferably a standard 12V DC power supply, compatible with the power supply standards of most passenger vehicles. The power supply module 14 is connected to the interface module 13, the main control module 11, the CAN decoding module 12, and the LED driver module, serving as the core power supply for the entire driver circuit 100 and providing a stable and compatible operating voltage for each functional module. The CAN decoding module 12 is connected to the vehicle's CAN bus via the interface module 13. It is used to receive vehicle status signals (such as door opening, side approach, driving mode switching, etc.) transmitted on the vehicle's CAN bus and to complete the decoding and conversion of the CAN bus signals. The main control module 11 is connected to the CAN decoding module 12 and is used to receive the decoded vehicle status signals. It generates LED drive signals based on the decoded vehicle status signals and transmits them to the LED light drive module 15. The LED light drive module 15 is connected to the LED indicator via the interface module 13 and is used to control the LED indicator's on / off state, color, and flashing state based on the LED drive signals.

[0021] The power supply module 14 includes three independent step-down modules: a first step-down module, a second step-down module, and a third step-down module. All three modules are connected to the interface module 13 to obtain the vehicle power supply voltage. The first step-down module is connected to the CAN decoding module 12 to convert the supply voltage into the first operating voltage of the CAN decoding module 12. The second step-down module is connected to the main control module 11 to convert the supply voltage into the second operating voltage of the main control module 11. The third step-down module is connected to the LED indicator to convert the supply voltage into the third operating voltage of the LED indicator. Thus, by using three independent step-down modules to power different modules—that is, different modules using different power supply links—effective hardware power supply isolation is achieved between the main control module 11, the CAN decoding module 12, and the LED indicator. This effectively prevents the LED indicator from affecting other modules through the power supply link and also avoids the problem of the front-end power supply branch affecting the downstream power supply voltage, improving the stability of circuit operation.

[0022] Further, as shown in Figure 2, the first step-down module includes an inductor L1, a capacitor C5, a voltage regulator chip U4, capacitors C8, C9, and C2. One end of the inductor L1 is connected to the power supply voltage of the vehicle power supply, serving as a front-end current limiter and surge protector. The other end of the inductor L1 and one end of the capacitor C5 are both connected to pin 2 of the voltage regulator chip U4, forming the voltage input terminal of the voltage regulator chip. The other end of the capacitor C5 and pin 1 of the voltage regulator chip U4 are both grounded, completing the filtering and grounding of the input circuit. Pin 3 of the voltage regulator chip U4 is the voltage output pin, outputting the first operating voltage CAN_5V to power the CAN decoding module 12. One end of each of the capacitors C8, C2, and C9 is connected to pin 3 of the voltage regulator chip U4, and the other end is grounded, forming a multi-stage output filtering circuit to filter out noise and ripple in the output voltage and reduce power supply interference to the CAN decoding module 12.

[0023] As shown in Figure 3, the second step-down module includes inductor L1, capacitor C105, voltage regulator chip U12, capacitors C3, C106, C107, C108, C109, C110, and C111. The specific connections of each component can be found in the circuit diagram shown in Figure 3, and will not be elaborated upon here. One end of inductor L11 is connected to the vehicle power supply voltage, enabling front-end current limiting protection. Pin 3 of voltage regulator chip U12 outputs the second operating voltage MCU_3V3. Capacitors C3, C106, C107, C108, C109, C110, and C111 form a high-density output filter network to filter out voltage ripple, ensuring accurate and smooth operation of the main control module 11.

[0024] As shown in Figure 4, the third step-down module is a dedicated power supply circuit for the LED indicator light. It converts the vehicle's 12V voltage into the third working voltage RGB1_5V adapted to the LED beads. It adopts the power management chip control mode and supports enable signal regulation. It includes power management chip U7, inductor PL1, diode D1, resistor R41, resistor R21, resistor R27, capacitor C10, capacitor C11, capacitor C12, capacitor C13, capacitor C14, capacitor C15, capacitor C16, capacitor C18, capacitor C19, capacitor C20, and capacitor C23.

[0025] The power supply from the vehicle power supply is filtered by capacitors C11 and C12 in parallel to remove input voltage noise before being connected to pin 8 of chip U7. Resistor R41 is connected between pins 7 and 8 of chip U7, serving as a voltage divider and providing chip startup protection. Pins 6 and 7 of chip U7 are grounded through capacitors C14 and C19 respectively, enabling internal circuit filtering. Capacitor C10 is connected between pins 1 and 2 of chip U7. Pin 2 of chip U7 is connected to the output node through inductor PL1 to output the third operating voltage RGB1_5V. The cathode of diode D1 is connected to pin 2 of chip U7, and the anode is grounded. The circuit provides freewheeling and reverse cutoff protection to prevent reverse breakdown. Capacitors C16, C18, C20, and C23 form the output filter circuit, with one end connected to the output node and the other end grounded. Resistor R21 and capacitor C15 are connected in parallel between pin 5 of chip U7 and the output node. One end of resistor R27 is connected to pin 5 of chip U7 and the other end is grounded, forming a voltage feedback loop to achieve precise control of the output voltage. Pin 3 of chip U7 is connected to the enable signal MCU_5V_EN output by the main control module 11. The enable signal MCU_5V_EN controls the start and stop of the third step-down module, enabling on-demand power supply for the LED indicator. Pin 4 of chip U7 is grounded through capacitor C13 to complete the chip reference voltage filtering.

[0026] To accommodate the independent power supply requirements of two sets of RGB tri-color light sources, the third step-down module in this embodiment is set to two sets. The circuit principle of the other set of third step-down modules is shown in Figure 10. The third step-down module shown in Figure 10 outputs the third working voltage RGB2_5V. The two sets of modules have the same structure and work independently, supplying power to the two sets of RGB light sources respectively, further avoiding power supply interference between the light groups.

[0027] As shown in Figure 5, interface module 13 includes connector J1 and its peripheral circuitry. Diodes D32 and D402 are used for power path control and to prevent reverse current flow. Diode D36 is the core protection device, clamping high-voltage surges / static electricity to protect the downstream circuitry. Pin 14 of connector J1 is connected to the +12V supply voltage of the vehicle power supply, which is filtered by capacitor C1. The third operating voltages RGB1_5V and RGB2_5V, output by the two sets of third step-down modules, are output to the positive terminal of the LED indicator through pins 2 and 13 of connector J1. Pins 7 and 8 of connector J1 are connected to the high and low bus lines of the CAN bus, respectively, for transmitting CAN bus signals.

[0028] As shown in Figure 6, the main control module 11 includes the main control chip U5 and its peripheral circuits. The specific connection relationship of each component can be referred to the circuit schematic shown in Figure 6, and will not be described in detail here.

[0029] Referring to Figure 7, the CAN decoding module 12 is the core of the vehicle's CAN bus communication, realizing the decoding and level conversion of CAN bus signals. It includes chip U6, resistors R1, R2, R36, R37, and R42. The specific connection relationship of each component can be referred to the circuit schematic shown in Figure 7. Among them, each resistor plays the role of current limiting and voltage pull-up stabilization to ensure the stability of communication signals. Pins 6 and 7 of chip U6 are connected to pins 7 and 8 of connector J1 in interface module 13, respectively, to connect to the vehicle's CAN bus through interface module 13.

[0030] Referring to Figure 8, the drive circuit 100 also includes a wireless communication module 16. The main control module 11 communicates bidirectionally with external terminal devices such as mobile phones and vehicle central control systems through the wireless communication module 16, supporting remote debugging of indicator light control parameters, real-time uploading of circuit operating status, and receiving external remote control commands. The circuit composition of the wireless communication module 16 and the connection relationship of each component can be referred to the circuit schematic shown in Figure 8, and will not be described in detail here.

[0031] The LED driver module 15 includes at least one driver unit. Each driver unit consists of a current-limiting resistor, a voltage-regulating resistor, and a MOSFET, forming a switching driver circuit with fast response, precise control, and no delay or stuttering. Specifically, the driver unit includes a first resistor, a second resistor, and a MOSFET. The LED driving signal is transmitted to the gate of the MOSFET through the first resistor, achieving current-limited signal transmission. The source of the MOSFET is grounded, and the collector is connected to the negative terminal of the LED indicator through the interface module 13. The positive terminal of the LED indicator is connected to the third operating voltage RGB1_5V, forming a complete LED power supply circuit. One end of the second resistor is connected to the gate of the MOSFET, and the other end is grounded, serving to regulate the gate voltage and prevent electrostatic discharge.

[0032] Referring to Figure 9, in some embodiments, the LED indicator includes two sets of RGB tri-color light sources, totaling six independent LED beads. Six independent drive units are configured to control each of the six LED beads. The main control module 11 outputs six LED drive signals to the six drive units. The third operating voltages RGB1_5V and RGB2_5V output by the two sets of third step-down modules are used to power the two sets of RGB tri-color light sources. Taking the drive unit of the first red LED bead as an example, the drive unit includes a first resistor R26, a second resistor R7, and a MOSFET Q12. One end of the first resistor R26 is connected to an LED drive signal R1, and the other end is connected to the gate of the MOSFET Q12. One end of the second resistor R7 is connected to the gate of the MOSFET Q12, and the other end is grounded. The source of the MOSFET Q12 is grounded, and the collector is connected to the negative terminal of the corresponding red LED bead through pin 3 of connector J1. The positive terminal of the red LED bead is connected to the third operating voltage RGB1_5V through pin 2 of connector J1. When the main control module 11 sends a high-level drive signal, the MOSFET Q12 turns on, and the red LED light is powered on and lit; when a low-level drive signal is sent, the MOSFET Q12 turns off, and the red LED light is turned off. The brightness and flashing frequency of the LED light can also be controlled by the PWM signal.

[0033] It is understood that in other embodiments of this invention, the LED indicator may also be composed of a single LED bead or multiple LED beads connected in series / parallel. In this case, the main control module 11 can control the working status of the six LED indicator lights respectively through six LED drive signals.

[0034] Optionally, the LED indicator light can be a car turn signal, brake light, or other ambient light; there is no limitation on this. This embodiment also provides a car LED indicator light device, integrating the aforementioned drive circuit 100 with the vehicle-mounted LED indicator light, with an overall layout conforming to the vehicle's appearance and functional requirements. The LED indicator light includes two outer rearview mirror indicator lights, two inner rearview mirror indicator lights, and a taillight. The main control module in the drive circuit 100 controls the operating status of these five indicator lights by outputting five LED control signals. The two outer rearview mirror indicator lights are respectively installed on the outer shells of the left and right rearview mirrors, and the two inner rearview mirror indicator lights are respectively installed on the inner shells of the left and right rearview mirrors. The taillight is installed on the exterior of the rear of the car. The inner shells of the left and right rearview mirrors refer to the sides of the left and right rearview mirrors closest to the vehicle body, while the outer shells refer to the sides of the left and right rearview mirrors furthest from the vehicle body.

[0035] In this embodiment, the vehicle status signals include a door opening command, a side vehicle approach warning signal, an intelligent driving mode activation command, a braking command, and a navigation mode selection command. The drive circuit 100 is connected to the outer indicator light of the rearview mirror, the inner indicator light of the rearview mirror, and the taillights. It is used to activate the taillights in the following ways: upon receiving a door opening command, the outer indicator light of the rearview mirror on the same side as the door illuminates; upon receiving a side vehicle approach warning signal, the rearview mirror indicator light on the same side as the side vehicle illuminates; upon receiving an intelligent driving mode activation command, the taillights illuminate in a first color; upon receiving a braking command, the taillights illuminate in a second color; and upon receiving a navigation mode selection command, the taillights illuminate in a third color.

[0036] Furthermore, the first color, the second color, and the third color are different colors; or, any two of the first color, the second color, and the third color are the same color, where the same color corresponds to the highlighted constant state and the blinking state, respectively.

[0037] Specifically, this indicator light device relies on the drive circuit 100 to achieve multi-scenario intelligent control. The control logic is as follows: 1. Door opening prompt: When the CAN decoding module of the drive circuit 100 receives the door opening command transmitted by the vehicle's CAN bus through the interface module, the main control module controls the outer indicator light of the rearview mirror on the same side as the door being opened to illuminate, serving as a door opening safety prompt; 2. Side vehicle approach warning: When the CAN decoding module receives the side vehicle approach warning signal transmitted by the vehicle's blind spot monitoring system through the interface module, the main control module drives the inner indicator light of the rearview mirror on the same side as the side vehicle approaching to illuminate, reminding the driver. 3. Intelligent driving mode indication: When the CAN decoding module receives the intelligent driving mode activation command through the interface module, the main control module controls the taillights to be constantly blue, indicating that the vehicle is in intelligent driving mode; 4. Brake warning: When the CAN decoding module receives the brake pedal trigger command through the interface module, the main control module controls the taillights to be constantly red, brightly reminding vehicles behind to slow down; 5. Navigation mode indication: When the CAN decoding module receives the navigation mode selection command through the interface module, the main control module controls the taillights to flash red, distinguishing different driving assistance modes.

[0038] The structures, proportions, and sizes illustrated in the accompanying diagrams of this manual are solely for the purpose of assisting those familiar with the art in understanding and reading the content disclosed herein. They are not intended to limit the feasibility of this creation and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, provided they do not affect the effectiveness or purpose of this creation, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms used in this manual, such as "one," "two," and "above," are merely for clarity of description and not intended to limit the scope of this creation's feasibility. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this creation's feasibility.

[0039] The above embodiments are merely illustrative of the principles and effects of this invention and are not intended to limit this invention. Any person skilled in the art may modify the above embodiments without departing from the spirit and scope of this invention. Therefore, the scope of protection of this invention should be as set forth in the following patent application claims.

[0040] 100: Car LED indicator light driver circuit

[0041] 11: Main Control Module

[0042] 12: CAN decoding module

[0043] 13: Interface Module

[0044] 14: Power Supply Module

[0045] 15: LED light driver module

[0046] 16: Wireless communication module

[0047] CAN_5V: First operating voltage

[0048] MCU_3V3: Second operating voltage

[0049] RGB1_5V, RGB2_5V: Third operating voltage

[0050] MCU_5V_EN: Enable signal

[0051] L1: Inductor

[0052] C2, C5, C8, C9: Capacitors

[0053] U4: Voltage regulator chip

[0054] L11: Inductor

[0055] C3, C105, C106, C107, C108, C109, C110, C111: Capacitors

[0056] U12: Voltage regulator chip

[0057] U7: Power Management Chip

[0058] PL1: Inductor

[0059] D1: Diode

[0060] R21, R27, R41: Resistors

[0061] C10, C11, C12, C13, C14, C15, C16, C18, C19, C20, C23: Capacitors

[0062] J1: Connector

[0063] D32, D36, D402: Diodes

[0064] C1: Capacitor

[0065] U5: Main control chip

[0066] U6: CAN decoding chip

[0067] R1, R2, R36, R37, R42: Resistors

[0068] Q12: MOSFET

[0069] R26: First resistor

[0070] R7: Second resistor

Claims

1. A driving circuit for an automotive LED indicator light, comprising: a main control module, a CAN decoding module, an interface module, a power supply module, and an LED driver module; the interface module is connected to an on-board power supply, the power supply module is connected to the interface module, the main control module, the CAN decoding module, and the LED driver module to provide power, the CAN decoding module is connected to a vehicle CAN bus through the interface module to receive vehicle status signals transmitted on the vehicle CAN bus, the main control module is connected to the CAN decoding module to generate an LED driving signal based on the vehicle status signal and transmit it to the LED driver module, and the LED driver module is connected to an LED indicator light through the interface module to control the LED indicator light to illuminate based on the LED driving signal; The power supply module includes a first step-down module, a second step-down module, and a third step-down module that are independent of each other. The first step-down module, the second step-down module, and the third step-down module are all connected to the interface module to obtain the power supply voltage of the vehicle power supply. The first step-down module is connected to the CAN decoding module to convert the power supply voltage into a first operating voltage of the CAN decoding module. The second step-down module is connected to the main control module to convert the power supply voltage into a second operating voltage of the main control module. The third step-down module is connected to the LED indicator to convert the power supply voltage into a third operating voltage of the LED indicator.

2. The automotive LED indicator driver circuit as described in claim 1, wherein the first step-down module includes an inductor L1, a capacitor C5, a voltage regulator chip U4, a capacitor C8, a capacitor C9, and a capacitor C2; one end of the inductor L1 is connected to the power supply voltage of the vehicle power supply, the other end of the inductor L1 and one end of the capacitor C5 are both connected to pin 2 of the voltage regulator chip U4, the other end of the capacitor C5 and pin 1 of the voltage regulator chip U4 are both grounded, and pin 3 of the voltage regulator chip U4 outputs the first operating voltage CAN_5V; one end of each of the capacitors C8, C2, and C9 is connected to pin 3 of the voltage regulator chip U4, and the other end is grounded.

3. The automotive LED indicator driving circuit as described in claim 1, wherein the second step-down module includes an inductor L1, a capacitor C105, a voltage regulator chip U12, a capacitor C3, a capacitor C106, a capacitor C107, a capacitor C108, a capacitor C109, a capacitor C110, and a capacitor C111; one end of the inductor L11 is connected to the power supply voltage of the vehicle power supply, the other end of the inductor L11 and one end of the capacitor C105 are both connected to pin 2 of the voltage regulator chip U12, the other end of the capacitor C105 and pin 1 of the voltage regulator chip U12 are both grounded, pin 3 of the voltage regulator chip U12 outputs the second operating voltage MCU_3V3, one end of each of the capacitors C3, C106, C107, C108, C109, C110, and C111 is connected to pin 3 of the voltage regulator chip U12, and the other end is grounded.

4. The automotive LED indicator driver circuit as described in claim 1, wherein the third step-down module includes a power management chip U7, an inductor PL1, a diode D1, resistors R41, R21, and R27, and capacitors C10, C11, C12, C13, C14, C15, C16, C18, C19, C20, and C23; the power supply from the vehicle power supply is filtered by capacitors C11 and C12 and then connected to the chip U7. Pin 8 of the power management chip U7 is connected to pins 7 and 8 via resistor R41. Pins 6 and 7 of the power management chip U7 are grounded via capacitors C14 and C19, respectively. Capacitor C10 is connected between pins 1 and 2 of the power management chip U7. Pin 2 of the power management chip U7 is connected to the output node via inductor PL1 to output the third operating voltage RGB1_5V. The cathode of diode D1 is connected to pin 2 of the power management chip U7, and the anode is grounded. One end of capacitors C16, C18, C20, and C23 is connected to the output node, and the other end is grounded. Resistor R21 and capacitor C15 are connected in parallel between pin 5 of the power management chip U7 and the output node. One end of resistor R27 is connected to pin 5 of the power management chip U7, and the other end is grounded. Pin 3 of the power management chip U7 is connected to an enable signal MCU_5V output by the main control module. _EN, pin 4 of the power management chip U7 is grounded through capacitor C13.

5. The automotive LED indicator driver circuit as described in claim 1, wherein the main control module includes a main control chip U5, pins 24, 36, and 48 of the main control chip U5 are all connected to the second operating voltage, the main control chip U5 outputs an enable signal MCU_5V_EN to the third step-down module through pin 10, the main control chip U5 outputs 6 control signals R1 / G1 / B1 / R2 / G2 / B2 to the LED driver module through pins 17, 16, 18, 43, 45, and 42, and the main control chip U5 is connected to the CAN decoding module through pins 33 and 34 for data interaction.

6. The automotive LED indicator driver circuit as described in claim 5, wherein the CAN decoding module includes a chip U6, resistors R1, R2, R36, R37, and R42; pins 6 and 7 of the chip U6 are respectively connected to the interface module to connect to the vehicle CAN bus through the interface module; resistor R1 is connected between pins 7 and 5 of the chip U6; resistor R2 is connected between pins 6 and 5 of the chip U6; pins 1 and 4 of the chip U6 are respectively connected to pins 34 and 33 of the main control chip U5; pin 1 of the chip U6 is connected to the second operating voltage through resistor R42; pin 4 of the chip U6 is connected to the second operating voltage through resistor R1; pin 8 of the chip U6 is connected to the second operating voltage through resistor R37; and pin 3 of the chip U6 is connected to the first operating voltage.

7. The automotive LED indicator drive circuit as described in claim 1 further includes a wireless communication module, through which the main control module communicates bidirectionally with an external terminal device.

8. The automotive LED indicator driving circuit as described in claim 1, wherein the LED driving module includes at least one driving unit, the driving unit including a first resistor, a second resistor and a MOSFET, the LED driving signal is transmitted to the gate of the MOSFET through the first resistor, the source of the MOSFET is grounded, the collector is connected to the negative terminal of the LED indicator through the interface module, the positive terminal of the LED indicator is connected to the third operating voltage, one end of the second resistor is connected to the gate of the MOSFET, and the other end is grounded.

9. An automotive LED indicator device, comprising an LED indicator and the driving circuit according to any one of claims 1-8; the LED indicator includes two outer rearview mirror indicator lights, two inner rearview mirror indicator lights, and a taillight, the two outer rearview mirror indicator lights being respectively disposed on the outer sides of the housings of the left and right rearview mirrors, the two inner rearview mirror indicator lights being respectively disposed on the inner sides of the housings of the left and right rearview mirrors, and the taillight being disposed on the exterior of the rear of the vehicle; the driving circuit is connected to the outer rearview mirror indicator lights, the inner rearview mirror indicator lights, and the taillight, and is used to drive the outer rearview mirror indicator lights on the same side as the door to illuminate when a door opening command is received, drive the rearview mirror indicator lights on the same side as the side vehicle to illuminate when a side vehicle approach warning signal is received, drive the taillight to illuminate in a first color when a smart driving mode activation command is received, drive the taillight to illuminate in a second color when a braking command is received, and drive the taillight to illuminate in a third color when a navigation mode selection command is received.

10. The automotive LED indicator device as claimed in claim 9, wherein the first color, the second color, and the third color are different colors; or, any two of the first color, the second color, and the third color are the same color, wherein the same color corresponds to a high-brightness constant-on state and a flashing state, respectively.

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