A diagnostic circuit of a body control module, an automobile

Abstract

This application provides a diagnostic circuit for a vehicle body control module and an automobile, relating to the field of electronic circuits. The circuit includes: a controller unit, a high-side drive unit, and a low-side drive unit; the first enable pin and the first sampling pin of the controller unit are connected to the corresponding input pins of the high-side drive unit, and the second enable pin and the second sampling pin of the controller unit are connected to the corresponding input pins of the low-side drive unit; the output pin of the high-side drive unit is connected to the positive terminal of the corresponding load of the automobile; the output pin of the low-side drive unit is connected to the negative terminal of the corresponding load of the automobile. Through the diagnostic strategy of high-side drive and low-side drive cooperation, a complete diagnosis of abnormal conditions before load driving is achieved at a relatively low cost, making up for the shortcomings of traditional solutions in that they cannot perform open circuit and short-ground diagnosis.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, specifically to a diagnostic circuit for a vehicle body control module and an automobile. Background Technology

[0002] The loads used in automobiles, such as lights, relays, solenoid valves, and wiper motors, are typically controlled using the output module of a controller unit. There are generally two control schemes: 1. High-side drive (HSD) method: The output pin of the high-side drive unit is connected to the positive terminal of the load, and the negative terminal of the load is grounded to ground at the nearest point in the vehicle. High-side drive modules typically use integrated chips such as STMicroelectronics' VND5T series and Infineon's BTT series. Figure 1 As shown. 2. Using the low-side drive (LSD) method, the output pin of the low-side drive unit is connected to the negative terminal of the load, and the positive terminal of the load is connected to the vehicle power supply. The low-side drive module typically uses integrated chips such as Infineon-BTS3408 and TLE7230. Figure 2 As shown.

[0003] In the process of realizing this application, the inventors discovered that using either the high-side drive method or the low-side drive method alone can only diagnose short-power supply faults of the load before driving, but cannot diagnose short-ground and open-circuit faults. Utility Model Content

[0004] In response, this application provides a diagnostic circuit for a vehicle body control module, which solves the problem that existing methods using only high-side drive or only low-side drive can only diagnose short-power supply faults of the load before driving, but cannot diagnose short-ground and open-circuit faults.

[0005] To achieve the above objectives, the embodiments of this application provide the following technical solutions:

[0006] The first aspect of this application discloses a diagnostic circuit for a vehicle body control module, including: a controller unit, a high-side drive unit, and a low-side drive unit;

[0007] The first enable pin and the first sampling pin of the controller unit are connected to the input pins corresponding to the high-side drive unit, and the second enable pin and the second sampling pin of the controller unit are connected to the input pins corresponding to the low-side drive unit.

[0008] The output pin of the high-side drive unit is connected to the positive terminal of the corresponding load of the vehicle;

[0009] The output pin of the low-side drive unit is connected to the negative terminal of the corresponding load of the vehicle.

[0010] Optionally, the diagnostic circuit of the above-mentioned vehicle body control module further includes a controllable power supply, wherein the output pin of the high-side drive unit is connected to the positive terminal of the load corresponding to the vehicle.

[0011] Optionally, in the diagnostic circuit of the above-mentioned vehicle body control module, when the first enable pin is enabled and the second enable pin is disabled, the AD value is obtained based on the sampling voltage of the first sampling pin, the voltage of the controller unit, and the system sampling accuracy. The AD value is used to determine the current state of the corresponding load of the vehicle.

[0012] Optionally, in the diagnostic circuit of the above-mentioned vehicle body control module, if the AD value is within a first preset range, then the current state of the load is that the low end of the load is short-grounded.

[0013] Optionally, in the diagnostic circuit of the above-mentioned vehicle body control module, if the AD value is within the second preset range, then the current state of the load is that the high-side of the load is short-grounded.

[0014] Optionally, in the diagnostic circuit of the above-mentioned vehicle body control module, if the AD value is within a third preset range, the current state of the load is that the load has not failed.

[0015] Optionally, in the diagnostic circuit of the above-mentioned vehicle body control module, if the AD value is within a first preset range, then the current state of the load is that the low end of the load is short-grounded.

[0016] If the AD value is within the second preset range, then the current state of the load is a high-end short ground condition.

[0017] If the AD value is within the third preset range, then the current state of the load is that the load has not failed.

[0018] Wherein, the maximum value of the third preset range is less than the minimum value of the first preset range, and the maximum value of the first preset range is less than the minimum value of the second preset range.

[0019] Optionally, in the diagnostic circuit of the above-mentioned body control module, the load is at least one of the following: lamp load, relay load, solenoid valve load, and wiper motor load.

[0020] The second aspect of this application discloses an automobile, including: a body control module and a diagnostic circuit for the body control module as disclosed in any of the first aspects.

[0021] Optionally, in the above-mentioned vehicles, the vehicles are electric vehicles or new energy vehicles.

[0022] The diagnostic circuit for the vehicle body control module provided in this application includes: a controller unit, a high-side drive unit, and a low-side drive unit; the first enable pin and the first sampling pin of the controller unit are connected to the corresponding input pins of the high-side drive unit, and the second enable pin and the second sampling pin of the controller unit are connected to the corresponding input pins of the low-side drive unit; the output pin of the high-side drive unit is connected to the positive terminal of the corresponding load of the vehicle; the output pin of the low-side drive unit is connected to the negative terminal of the corresponding load of the vehicle. Through the diagnostic strategy of high-side drive and low-side drive cooperation, a complete diagnosis of abnormal conditions before load driving can be achieved at a relatively low cost, making up for the shortcomings of traditional solutions in that they cannot perform open circuit and short-ground diagnosis. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0024] Figure 1 A schematic diagram of the structure of a high-side drive diagnostic circuit for a vehicle body control module provided in this application;

[0025] Figure 2 A schematic diagram of the structure of a low-side drive diagnostic circuit for a vehicle body control module provided in this application;

[0026] Figure 3 A circuit diagram of a diagnostic circuit for a vehicle body control module provided in an embodiment of this application;

[0027] Figure 4 A circuit diagram of a diagnostic circuit for another vehicle body control module provided in an embodiment of this application;

[0028] Figure 5 The diagram shows the current flow of a diagnostic circuit for a vehicle body control module provided in this application embodiment. Detailed Implementation

[0029] The technical solutions of the embodiments of this application 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. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0030] This application provides a diagnostic circuit for a vehicle body control module, which solves the problem that existing methods using only high-side drive or only low-side drive can only diagnose short-power supply faults of the load before driving, but cannot diagnose short-ground and open-circuit faults.

[0031] Please see Figure 3 The diagnostic circuit of the body control module mainly includes: a controller unit (MCU), a high-side drive unit (HSD), and a low-side drive unit (LSD).

[0032] The first enable pin EN-1 and the first sampling pin IS-1 of the controller unit MCU are connected to the input pins corresponding to the high-side drive unit HSD, and the second enable pin EN-2 and the second sampling pin IS-2 of the controller unit MCU are connected to the input pins corresponding to the low-side drive unit LSD.

[0033] The output pin of the high-side drive unit HSD is connected to the positive terminal of the corresponding load in the vehicle;

[0034] The output pin of the low-side drive unit (LSD) is connected to the negative terminal of the corresponding load of the vehicle.

[0035] In practical applications, the vehicle control module (DCM) can contain both a DCM chip that acts as a drive manager and a power supply chip that operates in intermittent conduction mode, providing efficient and stable voltage to its internal DCM and other circuits. Working together, they construct the highly integrated, intelligent, and efficient electronic and electrical architecture of modern automobiles.

[0036] The controller unit MCU can be the MCU in the body control module, which has at least four pins, namely the first enable pin EN-1, the first data acquisition pin IS-1, the second enable pin EN-2, and the second data acquisition pin IS-2.

[0037] The controller unit (MCU) is used to control the high-side drive unit (HSD) and the low-side drive unit (LSD) to pre-drive the load corresponding to the vehicle, and obtains the AD value used to determine the current state of the load corresponding to the vehicle through the sampling voltage of the first sampling pin and / or the sampling voltage of the second sampling pin.

[0038] Specifically, after determining that the load corresponding to the vehicle meets the preset driving requirements, the load corresponding to the vehicle is pre-driven by enabling the first enable pin, disabling the second enable pin, detecting the sampling voltage of the first sampling pin, and obtaining the AD value used to determine the current state of the load corresponding to the vehicle.

[0039] The high-side drive unit (HSD) is used to control the on / off state of the internal circuitry based on the enable state of the input pins.

[0040] Specifically, when the input pin of the high-side drive unit HSD is enabled, the internal circuit is turned on and can output a high level.

[0041] The low-side drive unit (LSD) is used to control the on / off state of the internal circuitry based on the enable state of the input pins.

[0042] Specifically, when the input pin of the low-side drive unit (LSD) is enabled, the internal circuit is turned on, and a low level can be output.

[0043] In some embodiments, such as Figure 4 As shown, the diagnostic circuit of the vehicle body control module may further include: a controllable power supply UB_SW, and the controllable power supply UB_SW is also connected between the output pin of the high-side drive unit HSD and the positive terminal of the corresponding load of the vehicle.

[0044] In practical applications, adding a controllable power supply UB_SW between the output pin of the high-side drive unit HSD and the positive terminal of the corresponding load in the vehicle can enable load open-circuit diagnosis before driving.

[0045] Specifically, before the corresponding load in the vehicle is put into operation, the controllable power supply UB_SW and the low-side drive unit LSD can be turned on separately. Since the high-side drive unit HSD is not outputting, if the second back-off pin IS-2 of the controller unit MCU samples normal current, it is considered that the load is online; if the second back-off pin IS-2 of the controller unit MCU fails to sample current, it proves that the load is open. At this time, the load drive can be stopped or the output can be maintained as required, and a fault can be reported to remind the car owner to check. After completing the pre-output diagnosis, the controllable power supply UB_SW can be turned off.

[0046] It should be noted that "load online" indicates that the circuit containing the load is in a closed circuit, while "load open circuit" indicates that the circuit outside the controller unit (MCU) is disconnected, which may be due to damage to the vehicle wiring harness or the load itself.

[0047] It should also be noted that in practice, the switching on and off of the controllable power supply UB_SW can be controlled by the controller unit MCU.

[0048] In some embodiments, the controller unit (MCU) needs to execute a diagnostic strategy that combines high-side drive and low-side drive. Specifically, when the controller unit (MCU) logic determines that the load meets the set drive conditions, it first performs a pre-drive. The controller unit (MCU) enables the first enable pin EN-1 to control the internal circuit of the high-side drive unit (HSD) to conduct and continuously output a high level for 200ms. During this period, the controller unit (MCU) controls the second enable pin EN-2 to be disabled, and the internal circuit of the low-side drive unit (LSD) is not turned on. At the same time, the current state of the load is determined by calculating the AD value by detecting the sampling voltage collected by the first sampling pin IS-1.

[0049] The formula for calculating the AD value is as follows:

[0050] , The sampling voltage is the first sampling pin IS-1. For the voltage of the controller unit MCU, This refers to the system sampling accuracy.

[0051] In practical applications, the voltage of the controller unit (MCU) is typically 5V, and the system sampling accuracy can be 2. 10 That is, 1024.

[0052] When the AD value is within the first preset range, the current state of the load is that the low end of the load is shorted to ground. The first preset range can be 20~1000. An AD value within this range indicates that the low end of the load is shorted to ground, allowing the circuit to conduct and sample normal current.

[0053] When the AD value is within the second preset range, the current state of the load is a short circuit to ground at the high end of the load. The second preset range can be 1000~1024. An AD value within this range indicates a short circuit to ground at the high end of the load, causing the circuit to conduct and sample overload current.

[0054] If either of the above two faults is detected, the low-side drive unit LSD output can be discontinued and a fault report can be submitted for repair.

[0055] When the AD value is within the third preset range, the current state of the load is that the load is not faulty. The third preset range can be 0~20. An AD value within this range proves that there is no conducting circuit, the load is not faulty, and the low-side drive unit (LSD) is continued to be turned on, allowing the circuit to conduct. The circuit direction is referenced... Figure 5 The load is working normally.

[0056] It is understandable that, in practice, the maximum value of the third preset range is less than the minimum value of the first preset range, and the maximum value of the first preset range is less than the minimum value of the second preset range.

[0057] In some embodiments, the load can be at least one of a lamp load, a relay load, a solenoid valve load, or a wiper motor load, depending on the application environment and user requirements, and all of these are within the protection scope of this application. Figures 3 to 5 All examples are based on the load of lighting fixtures.

[0058] By simultaneously driving the high-side and low-side loads within the controller unit (MCU), the load does not need to be connected to the vehicle power supply or ground. The high-side drive unit (HSD) and low-side drive unit (LSD) can select different driver chips based on the load power. For relatively low power loads, a self-built circuit using MOSFETs can be used to further control costs. The diagnostic strategy of coordinating high-side and low-side drives executed in the MCU enables pre-drive diagnostics of high-side or low-side grounding issues. By adding a controllable power supply (UB_SW), pre-drive open-circuit diagnostics can also be performed. The integrated solution provides comprehensive diagnostics for load drives, protecting the circuitry and ensuring vehicle safety.

[0059] Based on the above principles, the diagnostic circuit of the vehicle control module provided in this embodiment includes: a controller unit (MCU), a high-side drive unit (HSD), and a low-side drive unit (LSD); the first enable pin EN-1 and the first sampling pin IS-1 of the controller unit MCU are connected to the corresponding input pins of the high-side drive unit HSD, and the second enable pin EN-2 and the second sampling pin IS-2 of the controller unit MCU are connected to the corresponding input pins of the low-side drive unit LSD; the output pin of the high-side drive unit HSD is connected to the positive terminal of the corresponding load of the vehicle; the output pin of the low-side drive unit LSD is connected to the negative terminal of the corresponding load of the vehicle. Through the diagnostic strategy of high-side drive and low-side drive working together, a complete diagnosis of abnormal conditions before load driving is achieved at a relatively low cost, making up for the shortcomings of traditional solutions in that they cannot perform open circuit and short-ground diagnosis.

[0060] Optionally, another embodiment of this application also provides an automobile, including: a body control module and a diagnostic circuit for the body control module as described in any of the above embodiments, for diagnosing the state of the load that the body control module needs to control.

[0061] In some embodiments, the vehicle may be an electric vehicle or a new energy vehicle; of course, it is not limited to this, and may be determined according to the application environment and user needs, all of which are within the protection scope of this application.

[0062] The features described in the various embodiments of this specification can be substituted for or combined with each other. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. 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 modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0063] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0064] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0065] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A diagnostic circuit for a vehicle body control module, characterized in that, include: Controller unit, high-side drive unit, and low-side drive unit; The first enable pin and the first sampling pin of the controller unit are connected to the input pins corresponding to the high-side drive unit, and the second enable pin and the second sampling pin of the controller unit are connected to the input pins corresponding to the low-side drive unit. The output pin of the high-side drive unit is connected to the positive terminal of the corresponding load of the vehicle; The output pin of the low-side drive unit is connected to the negative terminal of the corresponding load of the vehicle.

2. The diagnostic circuit for the vehicle body control module according to claim 1, characterized in that, Also includes: Controllable power supply; The controllable power supply is also connected between the output pin of the high-side drive unit and the positive terminal of the load corresponding to the vehicle.

3. The diagnostic circuit for the vehicle body control module according to claim 1, characterized in that, With the first enable pin enabled and the second enable pin disabled, the AD value is obtained based on the sampling voltage of the first sampling pin, the voltage of the controller unit, and the system sampling accuracy. The AD value is used to determine the current state of the corresponding load of the vehicle.

4. The diagnostic circuit for the vehicle body control module according to claim 3, characterized in that, If the AD value is within the first preset range, then the current state of the load is that the load is short-grounded at the low end.

5. The diagnostic circuit for the vehicle body control module according to claim 3, characterized in that, If the AD value is within the second preset range, then the current state of the load is a high-end short ground condition.

6. The diagnostic circuit for the vehicle body control module according to claim 3, characterized in that, If the AD value is within the third preset range, then the current state of the load is that the load has not failed.

7. The diagnostic circuit for the vehicle body control module according to claim 3, characterized in that, If the AD value is within the first preset range, then the current state of the load is that the low end of the load is short-grounded. If the AD value is within the second preset range, then the current state of the load is a high-end short ground condition. If the AD value is within the third preset range, then the current state of the load is that the load has not failed. Wherein, the maximum value of the third preset range is less than the minimum value of the first preset range, and the maximum value of the first preset range is less than the minimum value of the second preset range.

8. The diagnostic circuit for the vehicle body control module according to claim 4, characterized in that, The load is at least one of the following: lamp load, relay load, solenoid valve load, and wiper motor load.

9. A car, characterized in that, include: The body control module and the diagnostic circuit of the body control module as described in any one of claims 1-8.

10. The automobile according to claim 9, characterized in that, The vehicle in question is an electric vehicle, or a new energy vehicle.

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