Control circuit and control method of rearview mirror with protection function

Abstract

The invention discloses a rearview mirror control circuit with protection and a control method, and relates to the technical field of rearview mirror electric control. In the circuit, a control module is electrically connected to a rearview mirror SOD module; the first end of the micro-control sub-module is electrically connected to the first end of the H-bridge driving sub-module, and the second end of the micro-control sub-module is electrically connected to the first end of the current acquisition feedback sub-module; the second end of the H-bridge driving sub-module is electrically connected to the second end of the current acquisition feedback sub-module and the first end of the first resistor R1, the third end of the H-bridge driving sub-module is electrically connected to the first end of the rearview mirror SOD module, the fourth end of the H-bridge driving sub-module is electrically connected to the second end of the rearview mirror SOD module, and the fifth end of the H-bridge driving sub-module is electrically connected to a power supply; the third end of the current acquisition feedback sub-module and the second end of the first resistor R1 are both grounded. According to the technical scheme, efficient control and real-time protection of the rearview mirror motor can be achieved.

Description

Technical Field

[0001] This application relates to the field of rearview mirror electronic control technology, specifically to a control circuit and control method for a rearview mirror with protection. Background Technology

[0002] In modern automotive design, rearview mirrors are a crucial component for ensuring driving safety. Traditional rearview mirrors primarily rely on physical adjustments and simple motor drives, but with the development of automotive electronics technology, rearview mirror control has gradually become more intelligent and electronic. Electronic rearview mirrors not only offer more flexible adjustment methods but also integrate more functions, such as automatic folding, heating and anti-fogging, and blind spot detection. However, with the increase in functionality, the complexity and reliability requirements of the control circuitry also increase.

[0003] Currently available rearview mirror control circuits typically employ simple switch control or basic motor drive circuits, which are insufficient to meet the requirements of multi-functional integration and high reliability. Especially in high-current and complex electromagnetic environments, the stability and protection mechanisms of rearview mirror control circuits are paramount. While existing H-bridge drive circuits can achieve bidirectional control of the rearview mirror motor, in practical applications, for rearview mirrors with built-in SOD control modules, leakage current at the H-bridge drive end can cause a voltage difference across the motor output, triggering the SOD module's stall protection and cutting off the output. This results in the rearview mirror failing to fold or unfold as intended. Summary of the Invention

[0004] This application provides a control circuit and control method for a rearview mirror with protection, which can achieve efficient control and real-time protection of the rearview mirror motor.

[0005] In a first aspect, this application provides a control circuit for a protected rearview mirror, the circuit comprising: a control module and a rearview mirror SOD module; the control module comprising: a microcontroller submodule, an H-bridge drive submodule, a current acquisition feedback submodule, a first resistor R1, and a power supply; the control module is electrically connected to the rearview mirror SOD module; a first terminal of the microcontroller submodule is electrically connected to a first terminal of the H-bridge drive submodule, and a second terminal of the microcontroller submodule is electrically connected to a first terminal of the current acquisition feedback submodule; a second terminal of the H-bridge drive submodule is electrically connected to a second terminal of the current acquisition feedback submodule and a first terminal of the first resistor R1, a third terminal of the H-bridge drive submodule is electrically connected to a first terminal of the rearview mirror SOD module, a fourth terminal of the H-bridge drive submodule is electrically connected to a second terminal of the rearview mirror SOD module, and a fifth terminal of the H-bridge drive submodule is electrically connected to the power supply; both the third terminal of the current acquisition feedback submodule and the second terminal of the first resistor R1 are grounded.

[0006] By adopting the above technical solution, the control module is electrically connected to the rearview mirror SOD module, thereby realizing the transmission and execution of control signals for the rearview mirror motor and ensuring that the rearview mirror motor can operate normally according to instructions. The first terminal of the microcontroller submodule is electrically connected to the first terminal of the H-bridge drive submodule, thereby transmitting control signals to the H-bridge drive submodule to achieve drive control of the rearview mirror motor. The second terminal of the microcontroller submodule is electrically connected to the first terminal of the current acquisition feedback submodule, thereby receiving current information transmitted by the current acquisition feedback submodule and realizing real-time monitoring of the rearview mirror motor's operating status. The second terminal of the H-bridge drive submodule is electrically connected to the second terminal of the current acquisition feedback submodule and the first terminal of the first resistor R1, thereby realizing current signal feedback and improving the accuracy of current acquisition, enhancing the system's monitoring capabilities. The fourth terminal of the H-bridge drive submodule is electrically connected to the second terminal of the rearview mirror SOD module, thereby realizing forward and reverse rotation control of the rearview mirror motor and improving the rearview mirror's adjustment capabilities. The third terminal of the current acquisition feedback submodule and the second terminal of the first resistor R1 are both grounded, thus forming a complete current loop and ensuring stable transmission and feedback of the current signal. The above circuit connection scheme enables efficient control and real-time protection of the rearview mirror motor.

[0007] In other words, this application reduces the probability of the rearview mirror failing to fold or unfold as expected through two strategies. First, before driving the rearview mirror, the voltage across the motor is lowered, specifically the voltage across the H-bridge drive submodule, thus eliminating the voltage difference across the motor caused by pre-drive leakage current. Second, if the rearview mirror SOD module triggers unexpected stall protection, cutting off the output, the rearview mirror may fail to fold or unfold normally. The current acquisition and feedback submodule collects the rearview mirror's operating current and transmits it to the microcontroller submodule. Based on the operating current of the rearview mirror SOD module, it determines whether the SOD module's operating status is abnormal. When the SOD module's operating status is abnormal, the microcontroller submodule controls the H-bridge drive submodule to re-drive the SOD module, enabling the rearview mirror to unfold or fold normally.

[0008] Optionally, the H-bridge driver submodule includes: a pre-drive unit, a first MOSFET Q1, a second MOSFET Q2, a third MOSFET Q3, a fourth MOSFET Q4, a second resistor R2, and a third resistor R3; the first terminal of the pre-drive unit is electrically connected to the first terminal of the microcontroller submodule, the second terminal of the pre-drive unit is electrically connected to the gate of the first MOSFET Q1, the third terminal of the pre-drive unit is electrically connected to the gate of the second MOSFET Q2, the fourth terminal of the pre-drive unit is electrically connected to the gate of the third MOSFET Q3, and the fifth terminal of the pre-drive unit is electrically connected to the gate of the fourth MOSFET Q4; the drain of the first MOSFET Q1 is electrically connected to the power supply, and the source of the first MOSFET Q1 is electrically connected to the first terminal of the microcontroller submodule R3. The drain of the second MOSFET Q2; the source of the second MOSFET Q2 is grounded; the drain of the third MOSFET Q3 is electrically connected to the power supply, and the source of the third MOSFET Q3 is electrically connected to the drain of the fourth MOSFET Q4; the source of the fourth MOSFET Q4 is grounded; the first terminal of the second resistor R2 is electrically connected to the source of the first MOSFET Q1 and the drain of the second MOSFET Q2, and the second terminal of the second resistor R2 is electrically connected to the first terminal of the first cutoff recovery control submodule; the first terminal of the third resistor R3 is electrically connected to the source of the third MOSFET Q3 and the drain of the fourth MOSFET Q4, and the second terminal of the third resistor R3 is electrically connected to the first terminal of the second cutoff recovery control submodule.

[0009] Optionally, the current acquisition feedback submodule includes: an input filtering unit, a feedback amplification unit, an output filtering unit, and a fourth resistor R4; the first terminal of the input filtering unit is electrically connected to the H-bridge drive submodule, the second terminal of the input filtering unit is electrically connected to the first terminal of the feedback amplification unit, and the third terminal of the input filtering unit is electrically connected to the first terminal of the fourth resistor R4; the second terminal of the feedback amplification unit is electrically connected to the first terminal of the output filtering unit; the second terminal of the output filtering unit is electrically connected to the second terminal of the microcontroller submodule; and the second terminal of the fourth resistor R4 is grounded.

[0010] Optionally, the input filtering unit includes: a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first capacitor C1, and a second capacitor C2; the first end of the fifth resistor R5 is electrically connected to the second end of the H-bridge driver submodule, and the second end of the fifth resistor R5 is electrically connected to the first end of the sixth resistor R6; the second end of the sixth resistor R6 is electrically connected to the first end of the seventh resistor R7 and the first end of the first capacitor C1; the second end of the seventh resistor R7 and the first end of the second capacitor C2 are both electrically connected to the first end of the feedback amplification unit; the second end of the first capacitor C1 is grounded, and the second end of the second capacitor C2 is grounded.

[0011] Optionally, the feedback amplification unit includes: an operational amplifier, an eighth resistor R8, a ninth resistor R9, and a third capacitor C3; the non-inverting input terminal of the operational amplifier is electrically connected to the second terminal of the input filtering unit; the first terminals of the eighth resistor R8, the ninth resistor R9, and the third capacitor C3 are all electrically connected to the inverting input terminal of the operational amplifier; the second terminal of the eighth resistor R8 is grounded; the second terminals of the ninth resistor R9 and the third capacitor C3 are both electrically connected to the output terminal of the operational amplifier; the output terminal of the operational amplifier is electrically connected to the first terminal of the output filtering unit.

[0012] Optionally, the output filtering unit includes: a tenth resistor R10 and a fourth capacitor C4; the first end of the tenth resistor R10 is electrically connected to the second end of the feedback amplification unit; the second end of the tenth resistor R10 and the first end of the fourth capacitor C4 are both electrically connected to the second end of the microcontroller submodule; the second end of the fourth capacitor C4 is grounded.

[0013] Optionally, the rearview mirror SOD module includes: a first cut-off recovery control submodule, a second cut-off recovery control submodule, and a rearview mirror motor; a first end of the first cut-off recovery control submodule is electrically connected to a third end of the H-bridge drive submodule, and a second end of the first cut-off recovery control submodule is electrically connected to a first end of the rearview mirror motor; a first end of the second cut-off recovery control submodule is electrically connected to a fourth end of the H-bridge drive submodule, and a second end of the second cut-off recovery control submodule is electrically connected to a second end of the rearview mirror motor.

[0014] Optionally, the first cutoff recovery control submodule includes: an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, a fifth capacitor C5, a sixth capacitor C6, a first diode D1, a fifth MOSFET Q5, and a first transistor Q7; the first terminals of the eleventh resistor R11, the twelfth resistor R12, and the fifth capacitor C5 are all electrically connected to the base of the first transistor Q7; the second terminal of the twelfth resistor R12 is electrically connected to the second terminal of the fifth capacitor C5; the thirteenth resistor R14, the twelfth resistor R15, the sixteenth resistor R16, the seventeenth resistor R17, the fifth capacitor C5, the sixth capacitor C6, the first diode D1, the fifth MOSFET Q5, and the first transistor Q7; the first terminal of the eleventh resistor R11, the first terminal of the twelfth resistor R12, the first terminal of the twelfth resistor R13, the first terminal of the twelfth resistor R14, the first terminal of the twelfth resistor R15, the first terminal of the twelfth resistor R16, the first terminal of the twelfth resistor R17, the first terminal of the twelfth resistor R16, the first terminal of the twelfth resistor R17, the first terminal of the twelfth resistor R16, the first terminal of the twelfth resistor R17, the first terminal of the twelfth resistor R17, the first terminal of the twelfth resistor R18, the first terminal of the twelfth resistor R19, the first terminal of the twelfth resistor R11, the first terminal of the twelfth resistor R19, the first terminal of the twelfth resistor R11, The first terminal of resistor R13 is electrically connected to the collector of the first transistor Q7, and the second terminal of the thirteenth resistor R13 is electrically connected to the gate of the fifth MOSFET Q5; the first terminal of the sixth capacitor C6 is electrically connected to the first terminal of the thirteenth resistor R13; the first terminals of the fourteenth resistor R14, the fifteenth resistor R15, the sixteenth resistor R16, and the seventeenth resistor R17 are all electrically connected to the source of the fifth MOSFET Q5; the anode of the first diode D1 is electrically connected to the source of the fifth MOSFET Q5, and the cathode of the first diode D1 is electrically connected to the drain of the fifth MOSFET Q5.

[0015] Optionally, the second cutoff recovery control submodule includes: an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a twenty-third resistor R23, a twenty-fourth resistor R24, a seventh capacitor C7, an eighth capacitor C8, a second diode D2, a sixth MOSFET Q6, and a second transistor Q8; the first terminals of the eighteenth resistor R18, the nineteenth resistor R19, and the seventh capacitor C7 are all electrically connected to the base of the second transistor Q8; the second terminal of the nineteenth resistor R19 is electrically connected to the second terminal of the seventh capacitor C7; the twentyth resistor R20, the nineteenth resistor R19, the twenty-third resistor R20, the twenty-fourth resistor R21, the twenty-third resistor R22, the twenty-fourth resistor R24, the seventh capacitor C7, the eighth capacitor C8, the second diode D2, the sixth MOSFET Q6, and the second transistor Q8; the first terminals of the eighteenth resistor R18, the nineteenth resistor R19, and the seventh capacitor C7 are all electrically connected to the base of the second transistor Q8; the second terminal of the nineteenth resistor R19 is electrically connected to the second terminal of the seventh capacitor C7; the second terminal of the nineteenth resistor R19 is electrically connected to the base ... The first terminal of resistor R20 is electrically connected to the collector of the second transistor Q8, and the second terminal of the twentieth resistor R20 is electrically connected to the gate of the sixth MOSFET Q6; the first terminal of the eighth capacitor C8 is electrically connected to the first terminal of the twentieth resistor R20; the first terminals of the twentieth resistor R21, the twentieth resistor R22, the twentieth resistor R23, and the twentieth resistor R24 ​​are all electrically connected to the source of the sixth MOSFET Q6; the anode of the second diode D2 is electrically connected to the source of the sixth MOSFET Q6, and the cathode of the second diode D2 is electrically connected to the drain of the sixth MOSFET Q6.

[0016] A second aspect of this application provides a control method for a protected rearview mirror, the method comprising: a current acquisition feedback submodule acquiring the operating current of the rearview mirror SOD module; transmitting the operating current to a microcontroller submodule, and determining whether the operating state of the rearview mirror SOD module is abnormal based on the operating current; when the operating state of the rearview mirror SOD module is abnormal, the microcontroller submodule controlling the H-bridge drive submodule to shut down the rearview mirror SOD module, thereby stopping the rearview mirror from working; after the shutdown operation, the microcontroller submodule continuously determining whether the operating state of the rearview mirror SOD module is abnormal based on the operating current; when the operating state of the rearview mirror SOD module is not abnormal, the microcontroller submodule controlling the H-bridge drive submodule to cancel the shutdown operation of the rearview mirror SOD module, thereby allowing the rearview mirror to work normally again.

[0017] In summary, one or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: The control module is electrically connected to the rearview mirror SOD module, thereby transmitting and executing control signals for the rearview mirror motor, ensuring that the motor operates normally according to instructions. The first terminal of the microcontroller submodule is electrically connected to the first terminal of the H-bridge drive submodule, transmitting control signals to the H-bridge drive submodule to drive the rearview mirror motor. The second terminal of the microcontroller submodule is electrically connected to the first terminal of the current acquisition and feedback submodule, receiving current information from it and enabling real-time monitoring of the rearview mirror motor's operating status. The second terminal of the H-bridge drive submodule is electrically connected to the second terminal of the current acquisition and feedback submodule and the first terminal of the first resistor R1, achieving current signal feedback and improving the accuracy of current acquisition, thus enhancing the system's monitoring capabilities. The fourth terminal of the H-bridge drive submodule is electrically connected to the second terminal of the rearview mirror SOD module, enabling forward and reverse rotation control of the rearview mirror motor and improving the rearview mirror's adjustability. The third terminal of the current acquisition and feedback submodule and the second terminal of the first resistor R1 are both grounded, forming a complete current loop to ensure stable transmission and feedback of the current signal. The above circuit connection scheme enables efficient control and real-time protection of the rearview mirror motor. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a control circuit for a protected rearview mirror provided in an embodiment of this application; Figure 2 This is a circuit diagram of an H-bridge driver submodule provided in an embodiment of this application; Figure 3 This is a circuit diagram of a current acquisition feedback submodule provided in an embodiment of this application; Figure 4 This is a circuit diagram of a rearview mirror SOD module provided in an embodiment of this application; Figure 5 This is a flowchart illustrating a control method for a protected rearview mirror provided in an embodiment of this application.

[0019] Explanation of reference numerals in the attached diagram: 1. Control module; 11. Microcontroller submodule; 12. H-bridge drive submodule; 121. Pre-drive unit; 13. Current acquisition and feedback submodule; 131. Input filtering unit; 132. Feedback amplification unit; 133. Output filtering unit; 2. Rearview mirror SOD module; 21. First cut-off recovery control submodule; 22. Second cut-off recovery control submodule. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0021] In the description of the embodiments in this application, the words "for example" or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "for example" or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design solutions. Specifically, the use of the words "for example" or "for instance" is intended to present the relevant concepts in a concrete manner.

[0022] In the description of the embodiments of this application, the term "multiple" means two or more. For example, multiple systems means two or more systems, and multiple screen terminals means two or more screen terminals. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. The terms "comprising," "including," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0023] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "electrical connection," "electrical connection," or "communication electrical connection" should be interpreted broadly. For example, "electrical connection," "electrical connection," or "communication electrical connection" can refer not only to a physical electrical connection, but also to an electrical connection or a signal electrical connection. For instance, it can be a direct electrical connection, i.e., a physical electrical connection, or an indirect electrical connection through at least one intermediate component, as long as the circuit is connected. It can also refer to the internal connection between two components. A signal electrical connection can refer not only to a signal electrical connection through a circuit, but also to a signal electrical connection through a medium, such as radio waves. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] This application provides a control circuit for a protected rearview mirror, referring to... Figure 1 This document illustrates a schematic diagram of a control circuit for a protected rearview mirror according to an embodiment of this application. The circuit includes a control module 1 and a rearview mirror SOD module 2. The control module 1 includes a microcontroller submodule 11, an H-bridge drive submodule 12, a current acquisition feedback submodule 13, a first resistor R1, and a power supply. The control module 1 is electrically connected to the rearview mirror SOD module 2. The first terminal of the microcontroller submodule 11 is electrically connected to the first terminal of the H-bridge drive submodule 12, and the second terminal of the microcontroller submodule 11 is electrically connected to the first terminal of the current acquisition feedback submodule 13. The second terminal of the H-bridge drive submodule 12 is electrically connected to the second terminal of the current acquisition feedback submodule 13 and the first terminal of the first resistor R1. The third terminal of the H-bridge drive submodule 12 is electrically connected to the first terminal of the rearview mirror SOD module 2, the fourth terminal of the H-bridge drive submodule 12 is electrically connected to the second terminal of the rearview mirror SOD module 2, and the fifth terminal of the H-bridge drive submodule 12 is electrically connected to the power supply. The third terminal of the current acquisition feedback submodule 13 and the second terminal of the first resistor R1 are both grounded.

[0025] Specifically, during the use of rearview mirrors, the rearview mirror motor may malfunction due to various reasons (such as overload, jamming, etc.). In order to monitor the working status of the rearview mirror motor in real time, cut off the power supply in time to protect the rearview mirror motor in abnormal situations, and restart the rearview mirror motor after normal operation is restored, this application designs a control circuit based on current acquisition feedback.

[0026] In the specific circuit connection, the circuit includes a control module 1 and a rearview mirror SOD module 2. The control module 1 consists of a microcontroller submodule 11, an H-bridge drive submodule 12, a current acquisition and feedback submodule 13, a first resistor R1, and a power supply. The control module 1 is electrically connected to the rearview mirror SOD module 2.

[0027] In the circuit, the first terminal of the microcontroller submodule 11 is electrically connected to the first terminal of the H-bridge drive submodule 12, and is responsible for sending control signals to the H-bridge drive submodule 12. The second terminal of the microcontroller submodule 11 is electrically connected to the first terminal of the current acquisition and feedback submodule 13, and is used to receive current data transmitted from the current acquisition and feedback submodule 13. Through this connection, the microcontroller submodule 11 can monitor the operating current of the rearview mirror motor in real time.

[0028] The H-bridge drive submodule 12 is the core component of the entire rearview mirror motor drive circuit. Its second terminal is electrically connected to the second terminal of the current acquisition feedback submodule 13 and the first terminal of the first resistor R1, used to receive feedback signals and provide the necessary drive current. The third and fourth terminals of the H-bridge drive submodule 12 are electrically connected to the first and second terminals of the rearview mirror SOD module 2, respectively, directly driving the rearview mirror motor. The fifth terminal of the H-bridge drive submodule 12 is electrically connected to the power supply, providing power to the entire rearview mirror motor drive circuit.

[0029] The third terminal of the current acquisition and feedback submodule 13 and the second terminal of the first resistor R1 are both grounded, forming a complete current loop. The current acquisition and feedback submodule 13 monitors the operating current of the rearview mirror motor in real time through the sampling resistor and transmits the current information to the microcontroller submodule 11. The microcontroller submodule 11 determines whether the rearview mirror motor is working properly based on the acquired current data.

[0030] With the above circuit design, when the rearview mirror motor is working normally, the current data monitored by the current acquisition feedback submodule 13 remains within the normal range, the microcontroller submodule 11 continues to maintain the normal working state of the H-bridge drive submodule 12, and the rearview mirror motor operates normally.

[0031] When the rearview mirror motor malfunctions (such as overload or jamming), the current acquisition and feedback submodule 13 detects the abnormal current and transmits this information to the microcontroller submodule 11. The microcontroller submodule 11 determines that the rearview mirror motor's operating state is abnormal based on a preset current threshold, and then controls the H-bridge drive submodule 12 to shut down the first cut-off recovery control submodule 21 and the second cut-off recovery control submodule 22, causing the rearview mirror motor to stop working and protecting the rearview mirror motor and its circuitry.

[0032] After the shutdown operation, the microcontroller submodule 11 continuously determines the operating status of the rearview mirror motor based on the current data provided by the current acquisition feedback submodule 13. When the rearview mirror motor is detected to have returned to normal, the microcontroller submodule 11 controls the H-bridge drive submodule 12 again to cancel the shutdown operation, allowing the rearview mirror motor to resume normal operation.

[0033] This circuit design not only protects the rearview mirror motor from damage, but also ensures that the rearview mirror quickly returns to normal function after the abnormal situation is resolved, thus improving the overall reliability and stability of the circuit.

[0034] In one possible implementation, refer to Figure 2 This document illustrates a circuit diagram of an H-bridge driver submodule provided in an embodiment of this application. The H-bridge driver submodule 12 includes: a pre-drive unit 121, a first MOSFET Q1, a second MOSFET Q2, a third MOSFET Q3, a fourth MOSFET Q4, a second resistor R2, and a third resistor R3; the first terminal of the pre-drive unit 121 is electrically connected to the first terminal of the microcontroller submodule 11, the second terminal of the pre-drive unit 121 is electrically connected to the gate of the first MOSFET Q1, the third terminal of the pre-drive unit 121 is electrically connected to the gate of the second MOSFET Q2, the fourth terminal of the pre-drive unit 121 is electrically connected to the gate of the third MOSFET Q3, and the fifth terminal of the pre-drive unit 121 is electrically connected to the gate of the fourth MOSFET Q4; the drain of the first MOSFET Q1 is electrically connected to a power supply. The source of the first MOSFET Q1 is electrically connected to the drain of the second MOSFET Q2; the source of the second MOSFET Q2 is grounded; the drain of the third MOSFET Q3 is electrically connected to the power supply, and the source of the third MOSFET Q3 is electrically connected to the drain of the fourth MOSFET Q4; the source of the fourth MOSFET Q4 is grounded; the first terminal of the second resistor R2 is electrically connected to the source of the first MOSFET Q1 and the drain of the second MOSFET Q2, and the second terminal of the second resistor R2 is electrically connected to the first terminal of the first cutoff recovery control submodule 21; the first terminal of the third resistor R3 is electrically connected to the source of the third MOSFET Q3 and the drain of the fourth MOSFET Q4, and the second terminal of the third resistor R3 is electrically connected to the first terminal of the second cutoff recovery control submodule 22.

[0035] Specifically, in the design of the vehicle rearview mirror control circuit, in order to achieve precise control of the rearview mirror motor and protect it under abnormal conditions, a circuit connection scheme based on the H-bridge drive submodule 12 was designed. This scheme aims to ensure the stable operation and timely protection of the rearview mirror motor through the coordinated work of the pre-drive unit 121 and multiple MOSFETs.

[0036] In the specific circuit connection, the H-bridge driver submodule 12 includes a pre-driver unit 121, a first MOSFET Q1, a second MOSFET Q2, a third MOSFET Q3, a fourth MOSFET Q4, a second resistor R2, and a third resistor R3. The first terminal of the pre-driver unit 121 is electrically connected to the first terminal of the microcontroller submodule 11, and is responsible for receiving control signals from the microcontroller submodule 11. The second, third, fourth, and fifth terminals of the pre-driver unit 121 are electrically connected to the gates of the first MOSFET Q1, the second MOSFET Q2, the third MOSFET Q3, and the fourth MOSFET Q4, respectively, and are used to drive the switching states of these MOSFETs. The pre-driver unit 121 is typically a dedicated driver chip. This chip is designed to convert the low-voltage control signals from the microcontroller into high-voltage, high-current drive signals suitable for driving power MOSFETs or IGBTs. The pre-driver chip not only simplifies circuit design but also provides additional protection functions, such as overcurrent protection, undervoltage lockout, and short-circuit protection, to improve system reliability.

[0037] In the circuit design of the H-bridge driver submodule 12, the drain of the first MOSFET Q1 is electrically connected to the power supply, and its source is electrically connected to the drain of the second MOSFET Q2. The source of the second MOSFET Q2 is grounded. Similarly, the drain of the third MOSFET Q3 is electrically connected to the power supply, and its source is electrically connected to the drain of the fourth MOSFET Q4. The source of the fourth MOSFET Q4 is also grounded. This connection method forms a typical H-bridge structure, which can control the forward and reverse rotation of the rearview mirror motor.

[0038] To monitor the operating status of the rearview mirror motor, a second resistor R2 and a third resistor R3 are connected between the source of the first MOSFET Q1 and the drain of the second MOSFET Q2, and between the source of the third MOSFET Q3 and the drain of the fourth MOSFET Q4, respectively. The second terminal of the second resistor R2 is electrically connected to the first terminal of the first cutoff recovery control submodule 21, and the second terminal of the third resistor R3 is electrically connected to the first terminal of the second cutoff recovery control submodule 22.

[0039] Through the above design, the microcontroller submodule 11 can precisely control the switching state of each MOSFET in the H-bridge drive submodule 12 via the pre-drive unit 121, thereby controlling the forward and reverse rotation of the rearview mirror motor. When the control signal causes the pre-drive unit 121 to drive the first MOSFET Q1 and the fourth MOSFET Q4 to conduct, while the second MOSFET Q2 and the third MOSFET Q3 are turned off, the rearview mirror motor will rotate forward. Conversely, when the pre-drive unit 121 drives the second MOSFET Q2 and the third MOSFET Q3 to conduct, while the first MOSFET Q1 and the fourth MOSFET Q4 are turned off, the rearview mirror motor will rotate in reverse.

[0040] Furthermore, when the rearview mirror motor is operating, the current changes of the rearview mirror motor are monitored through the second resistor R2 and the third resistor R3, allowing real-time acquisition of the motor's operating status information. Once an abnormal current is detected, the microcontroller submodule 11 can quickly adjust the state of each MOSFET through the pre-drive unit 121, shutting down the first cut-off recovery control submodule 21 and the second cut-off recovery control submodule 22 to cut off the power supply to the rearview mirror motor and protect the motor and circuitry from damage.

[0041] This design, based on the H-bridge drive submodule 12, not only achieves precise control and forward / reverse operation of the rearview mirror motor, but also provides timely protection measures when the rearview mirror motor malfunctions, ensuring the safety and stability of the rearview mirror motor and circuitry. Simultaneously, by monitoring the current status of the rearview mirror motor in real time, the circuit can quickly restart the motor after normal operation is restored, guaranteeing the normal function and reliability of the rearview mirror.

[0042] In one possible implementation, refer to Figure 3 The diagram illustrates a circuit diagram of a current acquisition feedback submodule provided in an embodiment of this application. The current acquisition feedback submodule 13 includes: an input filtering unit 131, a feedback amplification unit 132, an output filtering unit 133, and a fourth resistor R4. The first terminal of the input filtering unit 131 is electrically connected to the H-bridge driver submodule 12, the second terminal of the input filtering unit 131 is electrically connected to the first terminal of the feedback amplification unit 132, and the third terminal of the input filtering unit 131 is electrically connected to the first terminal of the fourth resistor R4. The second terminal of the feedback amplification unit 132 is electrically connected to the first terminal of the output filtering unit 133. The second terminal of the output filtering unit 133 is electrically connected to the second terminal of the microcontroller submodule 11. The second terminal of the fourth resistor R4 is grounded.

[0043] Specifically, to achieve real-time monitoring of the rearview mirror motor's operating status and to provide timely protection in abnormal situations, a circuit connection scheme based on the current acquisition and feedback submodule 13 was designed. This scheme ensures that the circuit can respond promptly and take appropriate control measures by accurately acquiring and feeding back the rearview mirror motor current.

[0044] In the specific circuit connection, the current acquisition feedback submodule 13 includes an input filtering unit 131, a feedback amplification unit 132, an output filtering unit 133, and a fourth resistor R4. The first terminal of the input filtering unit 131 is electrically connected to the H-bridge drive submodule 12 to receive the current signal from the rearview mirror motor. The second terminal of the input filtering unit 131 is electrically connected to the first terminal of the feedback amplification unit 132, and the third terminal of the input filtering unit 131 is electrically connected to the first terminal of the fourth resistor R4. Through filtering and voltage regulation, the stability and accuracy of the current signal are ensured.

[0045] The second terminal of the feedback amplification unit 132 is electrically connected to the first terminal of the output filter unit 133. The feedback amplification unit 132 amplifies and processes the input current signal through an operational amplifier and a precision resistor network, generating a stable voltage signal that reflects real-time changes in the current. The output filter unit 133 further smooths the processed signal, ensuring its purity and stability.

[0046] The second terminal of the output filter unit 133 is electrically connected to the second terminal of the microcontroller submodule 11, and the second terminal of the fourth resistor R4 is grounded. Through this connection, the current acquisition feedback submodule 13 can transmit the processed current signal to the microcontroller submodule 11 for real-time monitoring of the operating status of the rearview mirror motor.

[0047] Through the above design, the input filtering unit 131 first performs preliminary filtering and voltage regulation on the current signal from the H-bridge drive submodule 12 to remove high-frequency noise and transient interference, ensuring signal stability. The processed signal is then transmitted to the feedback amplification unit 132, where it is precisely amplified and processed by an operational amplifier and a resistor network to generate a voltage signal reflecting the operating current of the rearview mirror motor.

[0048] The output filtering unit 133 further smooths the amplified signal to remove residual noise and ensure signal purity. The final processed signal is then transmitted to the microcontroller submodule 11, which monitors the operating status of the rearview mirror motor in real time based on this signal.

[0049] When the rearview mirror motor is working normally, the current signal is within the preset range, and the microcontroller submodule 11 maintains normal drive status. When the rearview mirror motor malfunctions (such as overload, jamming, etc.), the current signal exceeds the normal range. The microcontroller submodule 11 determines that the working status of the rearview mirror motor is abnormal based on this signal, and then controls the H-bridge drive submodule 12 to take corresponding protection measures, such as shutdown, to prevent damage to the rearview mirror motor and circuit.

[0050] This design, based on the current acquisition and feedback submodule 13, not only enables real-time monitoring of the rearview mirror motor's operating status but also allows for timely response and protective measures in case of abnormalities, ensuring the circuit's safety and stability. Through precise current acquisition and feedback processing, the circuit effectively prevents damage to the rearview mirror motor, extends its service life, and improves the reliability of the rearview mirror control circuit.

[0051] In one possible implementation, refer to Figure 3The input filtering unit 131 includes: a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first capacitor C1, and a second capacitor C2; the first end of the fifth resistor R5 is electrically connected to the second end of the H-bridge drive submodule 12, and the second end of the fifth resistor R5 is electrically connected to the first end of the sixth resistor R6; the second end of the sixth resistor R6 is electrically connected to the first end of the seventh resistor R7 and the first end of the first capacitor C1; the second end of the seventh resistor R7 and the first end of the second capacitor C2 are both electrically connected to the first end of the feedback amplification unit 132; the second end of the first capacitor C1 is grounded, and the second end of the second capacitor C2 is grounded.

[0052] Specifically, in the vehicle rearview mirror control circuit, an input filtering unit 131 is designed to ensure the accuracy and stability of the current acquisition feedback. This unit filters and stabilizes the input current signal, ensuring the signal purity and reliability of the current acquisition feedback submodule 13.

[0053] In the specific circuit connection, the input filter unit 131 includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first capacitor C1, and a second capacitor C2. The input filter unit 131 is designed to perform preliminary processing on the current signal from the H-bridge drive submodule 12 to ensure the purity and stability of the signal.

[0054] In terms of specific connections, the first terminal of the fifth resistor R5 is electrically connected to the second terminal of the H-bridge driver submodule 12, receiving the current signal from the H-bridge driver submodule 12. The second terminal of the fifth resistor R5 is electrically connected to the first terminal of the sixth resistor R6. The second terminal of the sixth resistor R6 is electrically connected to the first terminal of the seventh resistor R7 and the first terminal of the first capacitor C1, forming a basic low-pass filter network to remove high-frequency noise.

[0055] The second terminal of the seventh resistor R7 and the first terminal of the second capacitor C2 are both electrically connected to the first terminal of the feedback amplifier unit 132. In this way, the combination of R7 and C2 further smooths the signal, removes transient interference and residual noise, and ensures that the signal received by the feedback amplifier unit 132 is stable and reliable.

[0056] The second terminal of the first capacitor C1 is grounded, and the second terminal of the second capacitor C2 is also grounded. The low-pass filter formed by these two capacitors and the resistor can effectively filter out high-frequency noise and ensure the purity of the signal.

[0057] Through the above design, the input filter unit 131 effectively filters and stabilizes the current signal transmitted from the H-bridge drive submodule 12. The series connection of the fifth resistor R5 and the sixth resistor R6, and the parallel connection of the first capacitor C1, constitute the primary filter circuit, which removes high-frequency noise from the input signal.

[0058] The seventh resistor R7 and the second capacitor C2 further smooth the signal, removing transient interference and residual noise. The processed signal is then transmitted to the feedback amplification unit 132, ensuring that the signal received by the current acquisition feedback submodule 13 has high purity and high stability.

[0059] Through the processing of the input filtering unit 131, the current acquisition feedback submodule 13 can more accurately reflect the working status of the rearview mirror motor, avoiding misjudgments caused by noise and interference. When the rearview mirror motor is working normally, the filtered current signal remains within the preset normal range; when the rearview mirror motor malfunctions, the filtered current signal exceeds the normal range, and the microcontroller submodule 11 can quickly determine the working status of the rearview mirror motor and take corresponding protective measures.

[0060] This design based on the input filter unit 131 not only improves the accuracy and stability of the current signal, but also enhances the circuit's anti-interference capability in complex electromagnetic environments, ensuring the reliability and safety of the rearview mirror control circuit. Through effective filtering and stabilization of the current signal, the circuit can better monitor the operating status of the rearview mirror motor, respond promptly, and take appropriate control measures to ensure the normal function and stable operation of the rearview mirror.

[0061] In one possible implementation, refer to Figure 3 The feedback amplification unit 132 includes an operational amplifier, an eighth resistor R8, a ninth resistor R9, and a third capacitor C3; the non-inverting input terminal of the operational amplifier is electrically connected to the second terminal of the input filter unit 131; the first terminals of the eighth resistor R8, the ninth resistor R9, and the third capacitor C3 are all electrically connected to the inverting input terminal of the operational amplifier; the second terminal of the eighth resistor R8 is grounded; the second terminals of the ninth resistor R9 and the third capacitor C3 are both electrically connected to the output terminal of the operational amplifier; the output terminal of the operational amplifier is electrically connected to the first terminal of the output filter unit 133.

[0062] Specifically, the current signal may be weak and susceptible to interference during the acquisition process, therefore it needs to be amplified and processed to ensure that the microcontroller submodule 11 can accurately receive the current change information. By designing the feedback amplification unit 132, the input signal can be accurately amplified, noise and interference can be eliminated, and a stable output signal can be generated.

[0063] In the specific circuit connection, the feedback amplification unit 132 includes an operational amplifier, an eighth resistor R8, a ninth resistor R9, and a third capacitor C3. The operational amplifier is used for signal amplification and processing, and its non-inverting input terminal is electrically connected to the second terminal of the input filter unit 131 to receive the pre-filtered current signal.

[0064] To ensure the accuracy of the amplification process, the first terminal of the eighth resistor R8, the first terminal of the ninth resistor R9, and the first terminal of the third capacitor C3 are all electrically connected to the inverting input of the operational amplifier. The second terminal of the eighth resistor R8 is grounded. Through this connection, the operational amplifier can form a negative feedback loop, stabilize the amplification factor, and suppress high-frequency noise.

[0065] The second terminal of the ninth resistor R9 and the second terminal of the third capacitor C3 are both electrically connected to the output terminal of the operational amplifier. The combination of R9 and C3 further stabilizes the output signal, reduces high-frequency interference and transient noise, and ensures the purity and stability of the output signal.

[0066] The output terminal of the operational amplifier is electrically connected to the first terminal of the output filter unit 133, which transmits the amplified and processed signal to the output filter unit 133 for further smoothing and stabilization, and finally transmits it to the microcontroller submodule 11.

[0067] Through the above design, the feedback amplification unit 132 can effectively and accurately amplify and process the input signal. The non-inverting input of the operational amplifier receives the current signal from the input filter unit 131. Through the feedback network formed by the eighth resistor R8 and the ninth resistor R9, the operational amplifier amplifies the signal, and the amplification factor is controlled by negative feedback to ensure the stability of the output signal.

[0068] The third capacitor C3, together with the ninth resistor R9, further filters out high-frequency noise and transient interference generated during amplification, ensuring the purity of the output signal. Finally, the amplified and processed signal is transmitted to the microcontroller submodule 11 through the output filter unit 133.

[0069] This design based on the feedback amplification unit 132 not only improves the amplification accuracy and stability of the current signal, but also enhances the circuit's anti-interference capability in noisy environments. Through precise signal amplification and processing, the microcontroller submodule 11 can more accurately monitor the operating status of the rearview mirror motor, promptly detect abnormalities, and take protective measures.

[0070] Finally, through the feedback amplification unit 132, the current acquisition feedback submodule 13 can output a high-precision, high-stability signal to ensure the reliable operation of the rearview mirror control circuit. When the rearview mirror motor is working normally, the amplified signal remains within the preset range; when the rearview mirror motor malfunctions, the amplified signal exceeds the normal range, and the microcontroller submodule 11 can respond quickly to protect the rearview mirror motor and circuit from damage.

[0071] In one possible implementation, refer to Figure 3 The output filter unit 133 includes: a tenth resistor R10 and a fourth capacitor C4; the first end of the tenth resistor R10 is electrically connected to the second end of the feedback amplifier unit 132; the second end of the tenth resistor R10 and the first end of the fourth capacitor C4 are both electrically connected to the second end of the microcontroller submodule 11; the second end of the fourth capacitor C4 is grounded.

[0072] Specifically, the amplified current signal may still be affected by some high-frequency noise and transient interference during transmission. Therefore, further filtering is required to ensure that the signal finally transmitted to the microcontroller submodule 11 is pure and stable. By designing the output filter unit 133, the amplified signal can be further smoothed to remove residual interference and ensure signal reliability.

[0073] In the specific circuit connection, the output filter unit 133 includes a tenth resistor R10 and a fourth capacitor C4. The output terminal of the feedback amplifier unit 132 is electrically connected to the first terminal of the tenth resistor R10. The tenth resistor R10 is used to limit the current, provide preliminary signal filtering, and reduce high-frequency noise.

[0074] The second terminal of the tenth resistor R10 and the first terminal of the fourth capacitor C4 are both electrically connected to the second terminal of the microcontroller submodule 11. The fourth capacitor C4 is used to further smooth the signal, eliminate residual transient interference and high-frequency noise, and ensure the purity and stability of the signal. The second terminal of the fourth capacitor C4 is grounded, providing a stable reference voltage and further improving signal stability.

[0075] Through the above design, the output filter unit 133 can effectively further smooth the signal output by the feedback amplifier unit 132. The tenth resistor R10 provides preliminary filtering by limiting current and reducing high-frequency noise and interference. The fourth capacitor C4, connected in parallel on the signal path, further eliminates transient interference and smooths the signal waveform, ensuring signal purity.

[0076] The processed signal is then transmitted to the microcontroller submodule 11, ensuring that the signal received by the microcontroller submodule 11 has high purity and high stability. This design ensures that the microcontroller submodule 11 accurately determines the operating status of the rearview mirror motor and takes appropriate control measures in a timely manner when abnormal situations occur.

[0077] Through further processing by the output filtering unit 133, the signal output by the current acquisition feedback submodule 13 achieves high precision and high stability, ensuring the reliable operation of the rearview mirror control circuit. When the rearview mirror motor is working normally, the filtered signal remains within a preset range; when the rearview mirror motor malfunctions, the filtered signal exceeds the normal range, and the microcontroller submodule 11 can respond quickly to protect the rearview mirror motor and circuit from damage. This design of the output filtering unit 133 not only improves signal reliability but also enhances the circuit's anti-interference capability, ensuring the stability and safety of the rearview mirror control circuit.

[0078] In one possible implementation, refer to Figure 1 and Figure 4 , Figure 4 A circuit diagram of a rearview mirror SOD module provided in an embodiment of this application is shown. The rearview mirror SOD module 2 includes: a first cut-off recovery control submodule 21, a second cut-off recovery control submodule 22, and a rearview mirror motor; the first terminal of the first cut-off recovery control submodule 21 is electrically connected to the third terminal of the H-bridge drive submodule 12, and the second terminal of the first cut-off recovery control submodule 21 is electrically connected to the first terminal of the rearview mirror motor; the first terminal of the second cut-off recovery control submodule 22 is electrically connected to the fourth terminal of the H-bridge drive submodule 12, and the second terminal of the second cut-off recovery control submodule 22 is electrically connected to the second terminal of the rearview mirror motor.

[0079] Specifically, rearview mirror motors may encounter various abnormal situations during operation, such as overload or jamming, which may damage the rearview mirror motor and its control circuit. In order to effectively control the operating status of the rearview mirror motor and perform timely protection operations when abnormalities are detected, a rearview mirror SOD module 2 containing a cut-off recovery control submodule was designed to achieve precise control and protection of the rearview mirror motor.

[0080] In the specific circuit connection, the rearview mirror SOD module 2 includes a first cut-off recovery control submodule 21, a second cut-off recovery control submodule 22, and a rearview mirror motor. The first terminal of the first cut-off recovery control submodule 21 is electrically connected to the third terminal of the H-bridge drive submodule 12, and is responsible for receiving control signals from the H-bridge drive submodule 12. The second terminal of the first cut-off recovery control submodule 21 is electrically connected to the first terminal of the rearview mirror motor, and is used to control the working state of the rearview mirror motor.

[0081] The first terminal of the second cut-off and recovery control submodule 22 is electrically connected to the fourth terminal of the H-bridge drive submodule 12, and is responsible for receiving control signals from the H-bridge drive submodule 12. The second terminal of the second cut-off and recovery control submodule 22 is electrically connected to the second terminal of the rearview mirror motor, and is also used to control the working state of the rearview mirror motor.

[0082] With the above design, when the rearview mirror motor is working normally, the H-bridge drive submodule 12 drives the first cut-off recovery control submodule 21 and the second cut-off recovery control submodule 22 through control signals, and the rearview mirror motor operates normally. When an abnormal operating state of the rearview mirror motor is detected (such as overload or jamming), the microcontroller submodule 11 obtains the abnormal current signal through the current acquisition feedback submodule 13, and immediately controls the H-bridge drive submodule 12 to shut down the first cut-off recovery control submodule 21 and the second cut-off recovery control submodule 22.

[0083] Specifically, upon receiving a shutdown signal, the first cut-off recovery control submodule 21 and the second cut-off recovery control submodule 22 will cut off the power supply to the rearview mirror motor, stopping its operation and preventing further damage. This cut-off operation effectively protects the rearview mirror motor and its control circuit, preventing damage in case of overload or jamming.

[0084] After the shutdown operation is performed, the microcontroller submodule 11 continuously monitors the operating status of the rearview mirror motor and acquires the current signal of the rearview mirror motor in real time through the current acquisition feedback submodule 13. When the rearview mirror motor is detected to have returned to normal (i.e., the current signal has returned to the normal range), the microcontroller submodule 11 controls the H-bridge drive submodule 12 to cancel the shutdown operation of the first cut-off recovery control submodule 21 and the second cut-off recovery control submodule 22.

[0085] After the shutdown operation is canceled, the first cut-off recovery control submodule 21 and the second cut-off recovery control submodule 22 are powered on again, and the rearview mirror motor resumes normal operation. This design not only enables real-time monitoring and abnormal protection of the rearview mirror motor, but also quickly restores the normal working state of the rearview mirror motor after the abnormal situation is resolved, ensuring the stability and reliability of the rearview mirror control circuit.

[0086] Through this cut-off and recovery control mechanism, the rearview mirror SOD module 2 can take timely protective measures when the rearview mirror motor malfunctions, and quickly restore normal function after the malfunction is resolved.

[0087] In one possible implementation, refer to Figure 4The first cut-off recovery control submodule 21 includes: an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, a fifth capacitor C5, a sixth capacitor C6, a first diode D1, a fifth MOSFET Q5, and a first transistor Q7; the first terminals of the eleventh resistor R11, the twelfth resistor R12, and the fifth capacitor C5 are all electrically connected to the base of the first transistor Q7; the second terminal of the twelfth resistor R12 is electrically connected to the second terminal of the fifth capacitor C5. The first terminal of the thirteenth resistor R13 is electrically connected to the collector of the first transistor Q7, and the second terminal of the thirteenth resistor R13 is electrically connected to the gate of the fifth MOSFET Q5; the first terminal of the sixth capacitor C6 is electrically connected to the first terminal of the thirteenth resistor R13; the first terminals of the fourteenth resistor R14, the fifteenth resistor R15, the sixteenth resistor R16, and the seventeenth resistor R17 are all electrically connected to the source of the fifth MOSFET Q5; the anode of the first diode D1 is electrically connected to the source of the fifth MOSFET Q5, and the cathode of the first diode D1 is electrically connected to the drain of the fifth MOSFET Q5.

[0088] Specifically, the first cut-off recovery control submodule 21 includes an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, a fifth capacitor C5, a sixth capacitor C6, a first diode D1, a fifth MOSFET Q5, and a first transistor Q7.

[0089] In the specific circuit connection, the first terminal of the eleventh resistor R11, the first terminal of the twelfth resistor R12, and the first terminal of the fifth capacitor C5 are all electrically connected to the base of the first transistor Q7, forming a base bias circuit to ensure that Q7 is in the conducting state under normal conditions. The second terminal of the twelfth resistor R12 is electrically connected to the second terminal of the fifth capacitor C5. This combination provides a stable base voltage.

[0090] The first terminal of the thirteenth resistor R13 is electrically connected to the collector of the first transistor Q7, and the second terminal is electrically connected to the gate of the fifth MOSFET Q5. The first terminal of the sixth capacitor C6 is electrically connected to the first terminal of the thirteenth resistor R13, providing further filtering to ensure the stability of the gate voltage.

[0091] The drain of the fifth MOSFET Q5 is connected to the positive terminal (+B) of the power supply, and its source is connected to the first terminals of the fourteenth resistor R14, the fifteenth resistor R15, the sixteenth resistor R16, and the seventeenth resistor R17, and is also connected to the anode of the first diode D1. The cathode of the first diode D1 is connected to the drain of Q5, forming reverse protection to prevent reverse current from damaging the MOSFET.

[0092] With the above design, when the first cut-off recovery control submodule 21 is working normally, the first transistor Q7 is turned on, and the collector current of Q7 provides a bias voltage to the gate of the fifth MOS transistor Q5 through the thirteenth resistor R13, so that Q5 is turned on, and the rearview mirror motor operates normally.

[0093] When the rearview mirror motor malfunctions (such as overload or jamming), the current acquisition and feedback submodule 13 detects the abnormal current and transmits the signal to the microcontroller submodule 11. After analysis, the microcontroller submodule 11 immediately issues a cut-off command. At this time, the first transistor Q7 is turned off, the gate voltage of Q5 is cut off, causing Q5 to turn off, cutting off the power supply to the rearview mirror motor and preventing damage to the rearview mirror motor and circuitry.

[0094] After the cut-off operation, the microcontroller submodule 11 continuously monitors the operating status of the rearview mirror motor and acquires the current signal in real time through the current acquisition and feedback submodule 13. When the rearview mirror motor is detected to have returned to normal (i.e., the current has returned to the normal range), the microcontroller submodule 11 issues a recovery command. The first transistor Q7 is turned on again, and the thirteenth resistor R13 provides a bias voltage to the gate of Q5 again, Q5 turns on, and the rearview mirror motor resumes normal operation.

[0095] This design achieves real-time monitoring and protection of the rearview mirror motor through the first cut-off recovery control submodule 21. When the rearview mirror motor malfunctions, the module can quickly cut off the power to prevent damage, and quickly restore the normal operation of the rearview mirror motor after the malfunction is resolved. This not only protects the rearview mirror motor and control circuit, but also improves the reliability and stability of the circuit.

[0096] In one possible implementation, refer to Figure 4The second cut-off recovery control submodule 22 includes: an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a twenty-third resistor R23, a twenty-fourth resistor R24, a seventh capacitor C7, an eighth capacitor C8, a second diode D2, a sixth MOSFET Q6, and a second transistor Q8; the first terminal of the eighteenth resistor R18, the first terminal of the nineteenth resistor R19, and the first terminal of the seventh capacitor C7 are all electrically connected to the base of the second transistor Q8; the second terminal of the nineteenth resistor R19 is electrically connected to the second terminal of the seventh capacitor C7. The first terminal of the twentieth resistor R20 is electrically connected to the collector of the second transistor Q8, and the second terminal of the twentieth resistor R20 is electrically connected to the gate of the sixth MOSFET Q6; the first terminal of the eighth capacitor C8 is electrically connected to the first terminal of the twentieth resistor R20; the first terminals of the twenty-first resistor R21, the twenty-second resistor R22, the twenty-third resistor R23, and the twenty-fourth resistor R24 ​​are all electrically connected to the source of the sixth MOSFET Q6; the anode of the second diode D2 is electrically connected to the source of the sixth MOSFET Q6, and the cathode of the second diode D2 is electrically connected to the drain of the sixth MOSFET Q6.

[0097] Specifically, the circuit working principle of the second cut-off recovery control submodule 22 is the same as that of the first cut-off recovery control submodule 21, so it will not be elaborated on here.

[0098] This application also provides a control method for a protected rearview mirror, applied in the circuit of any of the above embodiments, referring to... Figure 5 It shows a flowchart of a control method for a protected rearview mirror provided in an embodiment of this application, the method including steps S1-S5: Step S1: The current acquisition feedback submodule acquires the operating current of the rearview mirror SOD module.

[0099] Step S2: Transmit the operating current to the microcontroller submodule and determine whether there is any abnormality in the working status of the rearview mirror SOD module based on the operating current.

[0100] Step S3: When the working state of the rearview mirror SOD module is abnormal, the microcontroller submodule controls the H-bridge drive submodule to shut down the rearview mirror SOD module so that the rearview mirror stops working.

[0101] Step S4: After the shutdown operation is performed, the microcontroller submodule continues to determine whether there is any abnormality in the working status of the rearview mirror SOD module based on the working current.

[0102] Step S5: When there is no abnormality in the working status of the rearview mirror SOD module, the microcontroller submodule controls the H-bridge drive submodule to cancel the shutdown operation of the rearview mirror SOD module so that the rearview mirror can work normally again.

[0103] This application provides a control device for a protected rearview mirror, including the power supply circuit described in any of the above embodiments.

[0104] It should be noted that the circuits provided in the above embodiments are only illustrative examples of the division of functional modules. In practical applications, the functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. Furthermore, the circuit and method embodiments provided in the above embodiments belong to the same concept, and their specific implementation process is detailed in the circuit embodiments, which will not be repeated here.

[0105] A readable storage medium for a digital instrument stores instructions. When executed by one or more processors, these instructions cause the digital instrument to perform one or more methods as described in the above embodiments.

[0106] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0107] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0108] In the several embodiments provided in this application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the shown or discussed mutual couplings or direct couplings or communication connections may be through some service interfaces; indirect couplings or communication connections between apparatuses or units may be electrical or other forms.

[0109] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0110] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0111] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as USB flash drives, portable hard drives, magnetic disks, or optical disks.

[0112] The above are merely exemplary embodiments of this disclosure and should not be construed as limiting the scope of this disclosure. Any equivalent changes and modifications made in accordance with the teachings of this disclosure shall still fall within the scope of this disclosure. Those skilled in the art will readily conceive of other embodiments of this disclosure upon considering the specification and practicing the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not described in this disclosure.

Claims

1. A control circuit for a rearview mirror with protection, characterized in that, The circuit includes: a control module (1) and a rearview mirror SOD module (2); the control module (1) includes: a microcontroller submodule (11), an H-bridge drive submodule (12), a current acquisition feedback submodule (13), a first resistor R1, and a power supply; The control module (1) is electrically connected to the rearview mirror SOD module (2); The first end of the microcontroller submodule (11) is electrically connected to the first end of the H-bridge drive submodule (12), and the second end of the microcontroller submodule (11) is electrically connected to the first end of the current acquisition feedback submodule (13). The second end of the H-bridge drive submodule (12) is electrically connected to the second end of the current acquisition feedback submodule (13) and the first end of the first resistor R1. The third end of the H-bridge drive submodule (12) is electrically connected to the first end of the rearview mirror SOD module (2). The fourth end of the H-bridge drive submodule (12) is electrically connected to the second end of the rearview mirror SOD module (2). The fifth end of the H-bridge drive submodule (12) is electrically connected to the power supply. The third terminal of the current acquisition feedback submodule (13) and the second terminal of the first resistor R1 are both grounded.

2. The circuit according to claim 1, characterized in that, The H-bridge drive submodule (12) includes: a pre-drive unit (121), a first MOS transistor Q1, a second MOS transistor Q2, a third MOS transistor Q3, a fourth MOS transistor Q4, a second resistor R2, and a third resistor R3; The first end of the pre-drive unit (121) is electrically connected to the first end of the microcontroller submodule (11), the second end of the pre-drive unit (121) is electrically connected to the gate of the first MOS transistor Q1, the third end of the pre-drive unit (121) is electrically connected to the gate of the second MOS transistor Q2, the fourth end of the pre-drive unit (121) is electrically connected to the gate of the third MOS transistor Q3, and the fifth end of the pre-drive unit (121) is electrically connected to the gate of the fourth MOS transistor Q4. The drain of the first MOSFET Q1 is electrically connected to the power supply, and the source of the first MOSFET Q1 is electrically connected to the drain of the second MOSFET Q2. The source of the second MOSFET Q2 is grounded; The drain of the third MOSFET Q3 is electrically connected to the power supply, and the source of the third MOSFET Q3 is electrically connected to the drain of the fourth MOSFET Q4. The source of the fourth MOS transistor Q4 is grounded; The first end of the second resistor R2 is electrically connected to the source of the first MOS transistor Q1 and the drain of the second MOS transistor Q2, and the second end of the second resistor R2 is electrically connected to the first end of the first cut-off recovery control submodule (21). The first end of the third resistor R3 is electrically connected to the source of the third MOS transistor Q3 and the drain of the fourth MOS transistor Q4, and the second end of the third resistor R3 is electrically connected to the first end of the second cut-off recovery control submodule (22).

3. The circuit according to claim 1, characterized in that, The current acquisition feedback submodule (13) includes: an input filtering unit (131), a feedback amplification unit (132), an output filtering unit (133), and a fourth resistor R4; The first end of the input filtering unit (131) is electrically connected to the H-bridge driving submodule (12), the second end of the input filtering unit (131) is electrically connected to the first end of the feedback amplification unit (132), and the third end of the input filtering unit (131) is electrically connected to the first end of the fourth resistor R4. The second end of the feedback amplification unit (132) is electrically connected to the first end of the output filtering unit (133); The second end of the output filter unit (133) is electrically connected to the second end of the microcontroller submodule (11); The second terminal of the fourth resistor R4 is grounded.

4. The circuit according to claim 3, characterized in that, The input filtering unit (131) includes: a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first capacitor C1, and a second capacitor C2; The first end of the fifth resistor R5 is electrically connected to the second end of the H-bridge drive submodule (12), and the second end of the fifth resistor R5 is electrically connected to the first end of the sixth resistor R6. The second end of the sixth resistor R6 is electrically connected to the first end of the seventh resistor R7 and the first end of the first capacitor C1; The second end of the seventh resistor R7 and the first end of the second capacitor C2 are both electrically connected to the first end of the feedback amplification unit (132); The second terminal of the first capacitor C1 is grounded, and the second terminal of the second capacitor C2 is grounded.

5. The circuit according to claim 3, characterized in that, The feedback amplification unit (132) includes: an operational amplifier, an eighth resistor R8, a ninth resistor R9, and a third capacitor C3; The non-inverting input terminal of the operational amplifier is electrically connected to the second terminal of the input filter unit (131); The first terminal of the eighth resistor R8, the first terminal of the ninth resistor R9, and the first terminal of the third capacitor C3 are all electrically connected to the inverting input terminal of the operational amplifier. The second terminal of the eighth resistor R8 is grounded; The second terminal of the ninth resistor R9 and the second terminal of the third capacitor C3 are both electrically connected to the output terminal of the operational amplifier. The output terminal of the operational amplifier is electrically connected to the first terminal of the output filter unit (133).

6. The circuit according to claim 3, characterized in that, The output filtering unit (133) includes: a tenth resistor R10 and a fourth capacitor C4; The first terminal of the tenth resistor R10 is electrically connected to the second terminal of the feedback amplification unit (132); The second end of the tenth resistor R10 and the first end of the fourth capacitor C4 are both electrically connected to the second end of the microcontroller submodule (11); The second terminal of the fourth capacitor C4 is grounded.

7. The circuit according to claim 1, characterized in that, The rearview mirror SOD module (2) includes: a first cut-off recovery control submodule (21), a second cut-off recovery control submodule (22), and a rearview mirror motor; The first end of the first cut-off recovery control submodule (21) is electrically connected to the third end of the H-bridge drive submodule (12), and the second end of the first cut-off recovery control submodule (21) is electrically connected to the first end of the rearview mirror motor. The first end of the second cut-off recovery control submodule (22) is electrically connected to the fourth end of the H-bridge drive submodule (12), and the second end of the second cut-off recovery control submodule (22) is electrically connected to the second end of the rearview mirror motor.

8. The circuit according to claim 7, characterized in that, The first cut-off recovery control submodule (21) includes: eleventh resistor R11, twelfth resistor R12, thirteenth resistor R13, fourteenth resistor R14, fifteenth resistor R15, sixteenth resistor R16, seventeenth resistor R17, fifth capacitor C5, sixth capacitor C6, first diode D1, fifth MOS transistor Q5 and first transistor Q7; The first terminal of the eleventh resistor R11, the first terminal of the twelfth resistor R12, and the first terminal of the fifth capacitor C5 are all electrically connected to the base of the first transistor Q7. The second terminal of the twelfth resistor R12 is electrically connected to the second terminal of the fifth capacitor C5; The first terminal of the thirteenth resistor R13 is electrically connected to the collector of the first transistor Q7, and the second terminal of the thirteenth resistor R13 is electrically connected to the gate of the fifth MOS transistor Q5. The first terminal of the sixth capacitor C6 is electrically connected to the first terminal of the thirteenth resistor R13; The first terminals of the fourteenth resistor R14, the fifteenth resistor R15, the sixteenth resistor R16, and the seventeenth resistor R17 are all electrically connected to the source of the fifth MOS transistor Q5. The anode of the first diode D1 is electrically connected to the source of the fifth MOS transistor Q5, and the cathode of the first diode D1 is electrically connected to the drain of the fifth MOS transistor Q5.

9. The circuit according to claim 7, characterized in that, The second cut-off recovery control submodule (22) includes: an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a twenty-third resistor R23, a twenty-fourth resistor R24, a seventh capacitor C7, an eighth capacitor C8, a second diode D2, a sixth MOS transistor Q6, and a second transistor Q8; The first terminal of the eighteenth resistor R18, the first terminal of the nineteenth resistor R19, and the first terminal of the seventh capacitor C7 are all electrically connected to the base of the second transistor Q8. The second terminal of the nineteenth resistor R19 is electrically connected to the second terminal of the seventh capacitor C7; The first terminal of the twentieth resistor R20 is electrically connected to the collector of the second transistor Q8, and the second terminal of the twentieth resistor R20 is electrically connected to the gate of the sixth MOS transistor Q6. The first terminal of the eighth capacitor C8 is electrically connected to the first terminal of the twentieth resistor R20; The first terminals of the 21st resistor R21, the 22nd resistor R22, the 23rd resistor R23, and the 24th resistor R24 ​​are all electrically connected to the source of the 6th MOS transistor Q6. The anode of the second diode D2 is electrically connected to the source of the sixth MOS transistor Q6, and the cathode of the second diode D2 is electrically connected to the drain of the sixth MOS transistor Q6.

10. A control method for a rearview mirror with protection, characterized in that, The method, applied to the control circuit of the protected rearview mirror as described in any one of claims 1-9, comprises: The current acquisition feedback submodule (13) acquires the operating current of the rearview mirror SOD module (2); The operating current is transmitted to the microcontroller submodule (11), and the operating status of the rearview mirror SOD module (2) is determined based on the operating current to determine whether there is an abnormality. When the working state of the rearview mirror SOD module (2) is abnormal, the micro-control submodule (11) controls the H-bridge drive submodule (12) to shut down the rearview mirror SOD module (2) so that the rearview mirror stops working. After the shutdown operation is performed, the microcontroller submodule (11) continuously determines whether there is any abnormality in the working status of the rearview mirror SOD module (2) based on the working current; When the working state of the rearview mirror SOD module (2) is not abnormal, the micro-control submodule (11) controls the H-bridge drive submodule (12) to cancel the shutdown operation of the rearview mirror SOD module (2) so that the rearview mirror can work normally again.

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