Automobile system circuit supporting switch-off and implementing limp-home mode and automobile

Abstract

The application discloses a kind of support switch-off and realize the automobile system circuit of limping mode, when MCU enters limping mode state and one-key starting switch is not pressed when fault occurs, can be through latch circuit to take over logic processing circuit, to maintain the working state of MOSFET before MCU does not appear fault by logic processing circuit, that is, maintain the working state of load before MCU does not appear fault, so as to ensure that the function of the load of vehicle is not affected by MCU fault and normally work, instead of opening the function of load, improve the safety of vehicle, when one-key starting switch is pressed, by latch circuit, send close instruction to logic processing circuit, so as to control MOSFET off by logic processing circuit, that is, load is closed, avoid the situation that the function of opened load cannot be closed even after vehicle is parked, improve convenience.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of drive control, in particular to an automobile system circuit supporting switch-off and realizing limp-home mode. BACKGROUND

[0002] LIMP HOME limp-home mode is a vehicle fault protection mechanism. When a vehicle fails, in order to ensure the safety and reliability of the vehicle, the vehicle will automatically enter the LIMP HOME limp-home mode. In the LIMP HOME limp-home mode, the performance and function of the vehicle are limited, but the vehicle can still continue to run so as to safely drive back to the repair station for maintenance.

[0003] In order to ensure the normal operation of the LIMP HOME limp-home mode, it is necessary to add KL15 relay holding function in the vehicle circuit. KL15 relay is an important part of the vehicle circuit, which is responsible for controlling the power switch of the vehicle to ensure the normal operation of the vehicle. In the LIMP HOME limp-home mode, KL15 relay needs to be kept in an open state to ensure that the circuit system of the vehicle can work normally.

[0004] In the prior art, after the vehicle enters the LIMP HOME limp-home mode, some functions of the load are directly turned on, which leads to poor safety of the vehicle. For example, after the vehicle enters the LIMP HOME limp-home mode, the oil pump is turned on, and some hybrid cars use battery power when entering the LIMP HOME mode. At this time, the oil pump cannot be turned on, and the long time of turning on the oil pump will be dangerous to the vehicle. Moreover, the functions of the load turned on may not be able to be turned off even after the vehicle is parked, which is very inconvenient. SUMMARY

[0005] The present application provides an automobile system circuit supporting switch-off and realizing limp-home mode, to improve the safety and convenience of the automobile. The specific technical solutions are as follows:

[0006] In the first aspect, the present application provides an automobile system circuit supporting switch-off and realizing limp-home mode, comprising:

[0007] a fault output circuit and at least one set of control logic modules, each set of control logic modules comprising a metal-oxide-semiconductor field-effect transistor (MOSFET), a signal detection circuit, a logic processing circuit, and a latch circuit;

[0008] The signal detection circuit and the logic processing circuit of each set of control logic modules are connected with the fault output circuit, and the fault output circuit is connected with the micro control unit (MCU) of the automobile;

[0009] For each control logic module, the first end of the MOSFET of the module is connected to the power signal of the automobile, the second end of the MOSFET of the module is connected to the logic processing circuit of the module, the logic processing circuit of the module is connected to the MCU, the third end of the MOSFET of the module is connected to the load of the automobile and the latch circuit of the module respectively, the signal detection circuit of the module is connected to the one-key start switch of the automobile and the latch circuit of the module respectively, and the latch circuit of the module is connected to the logic processing circuit of the module;

[0010] The fault output circuit detects that the MCU is faulty, and outputs a fault signal enable signal to the signal detection circuit and the logic processing circuit of each control logic module respectively;

[0011] For each control logic module, the signal detection circuit of the module switches from a normal working state to a limp mode state after receiving the fault signal enable signal, and detects whether the one-key start switch is pressed;

[0012] The logic processing circuit of the module switches from the normal working state to the limp mode state after receiving the fault signal enable signal, and masks the system signal sent by the MCU;

[0013] When the signal detection circuit of the module detects that the one-key start switch is not pressed, the signal detection circuit sends a takeover instruction to the latch circuit of the module;

[0014] The latch circuit of the module receives the takeover instruction sent by the signal detection circuit of the module, collects the working state information of the MOSFET of the module before the MCU is faulty as current working state information, and sends the current working state information to the logic processing circuit of the module;

[0015] The logic processing circuit of the module receives the current working state information sent by the latch circuit of the module, and controls the MOSFET of the module to be turned on or turned off based on the current working state information;

[0016] When the signal detection circuit of the module detects that the one-key start switch is pressed, the signal detection circuit sends a shutdown instruction to the latch circuit of the module;

[0017] The latch circuit of the module receives the shutdown instruction sent by the signal detection circuit of the module, and sends the shutdown instruction to the logic processing circuit of the module;

[0018] The logic processing circuit of the module receives the shutdown instruction sent by the latch circuit of the module, and turns off the MOSFET of the module.

[0019] Optionally, after the fault output circuit detects that the MCU is normal, the fault output circuit sends a stop detection instruction to the signal detection circuit of each module and a recovery control instruction to the logic processing circuit of each module respectively;

[0020] For each group of control logic modules, the signal detection circuit of the group stops detecting whether the one-key start switch is pressed after receiving the stop detection instruction;

[0021] The logic processing circuit of the group re-receives the system signal sent by the MCU after receiving the recovery control instruction.

[0022] Optionally, the automobile system circuit supporting switch-off and limp-home mode further comprises a power anti-reverse device;

[0023] For each group of control logic modules, the first end of the MOSFET of the group is connected with the power anti-reverse device signal, and the power anti-reverse device is connected with the power signal of the automobile.

[0024] Optionally, the signal detection circuit of each group comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a voltage comparator, a voltage source and a first switch tube;

[0025] The one-key start switch is connected in parallel with the first resistor, one end of the first resistor is grounded, the other end is connected with one end of the second resistor, the other end of the second resistor is connected with one end of the third resistor and the comparison end of the voltage comparator respectively, the other end of the third resistor is connected with the fault output circuit, and the reference source end of the voltage comparator is grounded through the voltage source;

[0026] One end of the fourth resistor is connected with the fault output circuit, the other end is connected with the power positive end of the voltage comparator and the latch circuit of the group respectively, the power negative end of the voltage comparator is grounded, the output end of the voltage comparator is connected with the first signal end of the first switch tube, the output end of the first switch tube is connected with the latch circuit of the group, and the second signal end of the first switch tube is grounded.

[0027] Optionally, the logic processing circuit of each group is a driving chip supporting level switching function, serial peripheral interface (SPI) control function and level control function.

[0028] Optionally, the latch circuit of each group is further connected with the MCU signal;

[0029] The MCU sends an activation instruction to the latch circuit of each group to activate the latch circuit when the automobile is started.

[0030] Optionally, the latch circuit of each group comprises a NOT gate, a first OR gate, a first diode, a second diode and a tri-state single buffer gate.

[0031] The input end of the NOT gate is connected with the MOSFET signal of the group, the output end of the NOT gate is connected with the first input end of the first OR gate, the second input end of the first OR gate is connected with the signal detection circuit of the group, the output end of the first OR gate is connected with the output enable end of the tri-state single buffer gate, the anode of the first diode is connected with the MCU, the cathode of the first diode is connected with the cathode of the second diode and the input end of the tri-state single buffer gate respectively, the output end of the tri-state single buffer gate is connected with the logic processing circuit of the group, and the anode of the second diode is connected with the logic processing circuit of the group.

[0032] Optionally, the fault output circuit comprises a NOT gate and a second switch tube.

[0033] The first input end of the NOT gate is connected with the MCU, the output end of the NOT gate is connected with the first signal end of the second switch tube, the second signal end of the second switch tube is connected with the key electric relay of the automobile, and the output end of the second switch tube is connected with the signal detection circuit and the logic processing circuit of each group respectively.

[0034] Optionally, the second input end of the NOT gate is connected with the overvoltage fault end of the power supply of the automobile, and the third input end of the NOT gate is connected with the undervoltage fault end of the power supply of the automobile.

[0035] In the second aspect, the application provides an automobile, comprising an automobile system circuit and a vehicle body, wherein the automobile system circuit is installed on the vehicle body, and the automobile system circuit is the automobile system circuit capable of supporting switch-off and realizing limp-home mode according to any one of the first aspect.

[0036] From the above, the automobile system circuit supporting switch-off and realizing limp-home mode provided by the embodiment of the application comprises a fault output circuit and at least one set of control logic modules, each set of control logic modules comprising a MOSFET, a signal detection circuit, a logic processing circuit and a latch circuit, the signal detection circuit and the logic processing circuit of each set of control logic modules being signal connected with the fault output circuit, the fault output circuit being further signal connected with the MCU of the automobile, for each set of control logic modules, the first end of the MOSFET of the set being signal connected with the power supply of the automobile, the second end of the MOSFET of the set being signal connected with the logic processing circuit of the set, the logic processing circuit of the set being signal connected with the MCU, the third end of the MOSFET of the set being signal connected with the load of the automobile and the latch circuit of the set respectively, the signal detection circuit of the set being signal connected with the one-key starting switch of the automobile and the latch circuit of the set respectively, the latch circuit of the set being signal connected with the logic processing circuit of the set, the fault output circuit detecting the fault of the MCU, outputting the fault signal enable signal to the signal detection circuit and the logic processing circuit of each set of control logic modules, for each set of control logic modules, the signal detection circuit of the set switching from the normal working state to the limp-home mode state after receiving the fault signal enable signal, and detecting whether the one-key starting switch is pressed, the logic processing circuit of the set switching from the normal working state to the limp-home mode state after receiving the fault signal enable signal, and shielding the system signal sent by the MCU, when the signal detection circuit of the set detects that the one-key starting switch is not pressed, sending the takeover instruction to the latch circuit of the set, the latch circuit of the set receiving the takeover instruction sent by the signal detection circuit of the set, collecting the working state information of the MOSFET of the set before the fault of the MCU as the current working state information and sending the current working state information to the logic processing circuit of the set, the logic processing circuit of the set receiving the current working state information sent by the latch circuit of the set, and controlling the MOSFET of the set to be turned on or off based on the current working state information, when the signal detection circuit of the set detects that the one-key starting switch is pressed, sending the closing instruction to the latch circuit of the set, the latch circuit of the set receiving the closing instruction sent by the signal detection circuit of the set, and sending the closing instruction to the logic processing circuit of the set, the logic processing circuit of the set receiving the closing instruction sent by the latch circuit of the set, and closing the MOSFET of the set.Therefore, in this embodiment of the invention, when the MCU malfunctions and enters limp mode and the one-button start switch is not pressed, the latch circuit can take over the logic processing circuit. The logic processing circuit then controls the MOSFET to maintain its operating state as it did before the MCU malfunction, thus maintaining the load's operating state before the MCU malfunction. This ensures that the vehicle's load function is not affected by the MCU malfunction and continues to operate normally, rather than simply activating the load function, thereby improving vehicle safety. When the one-button start switch is pressed, the latch circuit sends a shutdown command to the logic processing circuit, which then controls the MOSFET to shut down, effectively turning off the load. This avoids the situation where the activated load function cannot be turned off even after the vehicle is parked, improving convenience.

[0037] The innovative aspects of this invention include:

[0038] 1. When the MCU malfunctions and enters limp mode, and the one-button start switch is not pressed, the latch circuit can take over the logic processing circuit. This allows the logic processing circuit to control the MOSFET to maintain its operating state as it did before the MCU malfunction, thus ensuring the load functions normally without being affected by the MCU failure. This improves vehicle safety. When the one-button start switch is pressed, the latch circuit sends a shutdown command to the logic processing circuit, which then controls the MOSFET to shut down, effectively turning off the load. This prevents the load from remaining active even after the vehicle is parked, improving convenience.

[0039] 2. The automotive system circuit that supports switch-off and implements limp mode provided in this embodiment of the invention is built entirely in hardware, with lower labor costs and a faster development cycle.

[0040] 3. The automotive system circuit that supports switch-off and limp mode provided in this embodiment of the invention can be independent of the overall function of the vehicle, forming a self-contained module, which improves the degree of modularity. When not needed, this automotive system circuit that supports switch-off and limp mode can be removed, which is flexible, convenient, and easy to control costs.

[0041] 4. Reverse power connection is prevented by installing a power reverse protection device between the car's power supply and the MOSFET.

[0042] 5、In the fault output circuit detects MCU normal, by sending stop detection instruction to each group of signal detection circuit and resume control instruction to each group of logic processing circuit, control each group of signal detection circuit stop detection one key start switch is pressed, and control each group of logic processing circuit continue to work according to the system command issued by MCU, keep the vehicle normal work.

[0043] 6、By setting the voltage comparator, when the one key start switch is not pressed, the voltage of the comparison end of the voltage comparator is greater than the voltage of the reference source end, the voltage comparator outputs high level to the latch circuit, that is, sends the takeover instruction to the latch circuit, so as to control the MOSFET through the logic processing circuit to maintain the working state before the MCU fails, when the one key start switch is pressed, the voltage of the comparison end of the voltage comparator is less than the voltage of the reference source end, the voltage comparator outputs low level to the latch circuit, that is, sends the close instruction to the latch circuit, so as to control the MOSFET through the logic processing circuit to close.

[0044] 7、By using the driving chip supporting level switching function, SPI control function and level control function, the logic processing circuit is switched from normal working state to limp mode state after receiving the fault signal enable signal, and the system signal issued by MCU is shielded, at the same time, the current working state information sent by the latch circuit is received, and the MOSFET is controlled to open or close based on the current working state information, after the MCU recovers, the resume control instruction is received, the system signal issued by MCU is received again, and the normal work according to the system command issued by MCU is continued.

[0045] 8、In order to ensure that each group of latch circuit can work normally, MCU sends activation instruction to each group of latch circuit to activate each latch circuit when the vehicle starts.

[0046] 9、By setting the three state single buffer gate, the latch circuit receives the takeover instruction sent by the signal detection circuit, collects the working state information of the MOSFET before the MCU fails as the current working state information sent to the logic processing circuit, and then controls the working state of the MOSFET to keep the same as before the MCU fails, so as to ensure that the vehicle works normally without being affected by the MCU failure, and realizes that the latch circuit receives the close instruction sent by the signal detection circuit, and sends the close instruction to the logic processing circuit, and then closes the MOSFET, so as to achieve the purpose of closing the load.

[0047] 10、By setting NAND gate and second switch tube, the fault output circuit detects that the MCU fails, and outputs the fault signal enable signal to the signal detection circuit and the logic processing circuit respectively.

[0048] 11. The overvoltage fault end signal of the power supply of the automobile is connected with the second input end of the NAND gate, and the undervoltage fault end signal of the power supply of the automobile is connected with the third input end of the NAND gate, so that the load is closed when the overvoltage fault or the undervoltage fault of the power supply occurs.

[0049] 12. The automobile provided by the embodiment of the application comprises an automobile system circuit and a vehicle body, the automobile system circuit is installed on the vehicle body, and when the MCU enters a limp mode state due to a fault and a one-key starting switch is not pressed, the latch circuit can take over the logic processing circuit, so that the MOSFET is controlled by the logic processing circuit to maintain the working state before the fault of the MCU, that is, the working state of the load before the fault of the MCU, so that the function of the load of the vehicle is ensured to work normally without being affected by the fault of the MCU, instead of being started, and the safety of the vehicle is improved; when the one-key starting switch is pressed, the latch circuit sends a closing instruction to the logic processing circuit, so that the MOSFET is controlled by the logic processing circuit to be closed, that is, the load is closed, and the situation that the started function of the load cannot be closed even after the vehicle is parked is avoided, and the convenience is improved.

[0050] Of course, implementing any product or method of the application does not necessarily require all the advantages described above. BRIEF DESCRIPTION OF DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only show some embodiments of the application. Those skilled in the art can also obtain other drawings according to these drawings without any creative effort.

[0052] Figure 1 The structural schematic diagram of the automobile system circuit supporting switch-off and realizing the limp mode provided by the embodiment of the application;

[0053] Figure 2 The structural schematic diagram of the signal detection circuit provided by the embodiment of the application;

[0054] Figure 3 The structural schematic diagram of the logic processing circuit provided by the embodiment of the application;

[0055] Figure 4 The structural schematic diagram of the latch circuit provided by the embodiment of the application;

[0056] Figure 5 The structural schematic diagram of the fault output circuit provided by the embodiment of the application;

[0057] Figure 6 A structure schematic diagram of an automobile is provided for the embodiment of the present application.

[0058] Figures 1-6 In the embodiment, 1 fault output circuit, 11 or non-gate, 12 second switch tube, 2 MOSFET, 3 signal detection circuit, 31 first resistor, 32 second resistor, 33 third resistor, 34 fourth resistor, 35 voltage comparator, 36 voltage source, 37 first switch tube, 4 logic processing circuit, 5 latch circuit, 51 non-gate, 52 first or gate, 53 first diode, 54 second diode, 55 tri-state single buffer gate, 6 power supply, 7 load, 8 one-key starting switch, 9 power supply anti-reverse device, 10 key electric relay, 20 automobile system circuit, 21 vehicle body. DETAILED DESCRIPTION

[0059] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0060] It should be noted that the terms "comprising" and "having" and any variations thereof in the embodiments of the present application and the drawings are intended to cover non-exclusive inclusion. For example, the processes, methods, systems, products or devices comprising a series of steps or units are not limited to the listed steps or units, but can optionally further comprise steps or units not listed, or can optionally further comprise other steps or units inherent to the processes, methods, products or devices.

[0061] The embodiment of the present application discloses an automobile system circuit supporting switch-off and realizing limp-home mode and an automobile, which can improve safety and convenience. The embodiments of the present application will be described in detail below.

[0062] Figure 1 A structure schematic diagram of an automobile system circuit supporting switch-off and realizing limp-home mode is provided for the embodiment of the present application. Referring to Figure 1 The automobile system circuit supporting switch-off and realizing limp-home mode provided by the embodiment of the present application comprises a fault output circuit 1 and at least one group of control logic modules, each group of control logic modules comprising a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) 2, a signal detection circuit 3, a logic processing circuit 4 and a latch circuit 5.

[0063] The signal detection circuit 3 and the logic processing circuit 4 of each control logic module are connected with the fault output circuit 1, and the fault output circuit 1 is also connected with the MCU (Microcontroller Unit) of the automobile.

[0064] For each control logic module, the first end of the MOSFET 2 of the module is connected with the power supply 6 of the automobile, the second end of the MOSFET 2 of the module is connected with the logic processing circuit 4 of the module, the logic processing circuit 4 of the module is connected with the MCU, the third end of the MOSFET 2 of the module is connected with the load 7 of the automobile and the latch circuit 5 of the module respectively, the signal detection circuit 3 of the module is connected with the one-key starting switch 8 of the automobile and the latch circuit 5 of the module respectively, and the latch circuit 5 of the module is connected with the logic processing circuit 4 of the module.

[0065] The load 7 can be a wiper, an oil pump or a brake light. The number of control logic modules is the same as the number of loads 7 to be controlled.

[0066] Continuing to refer to Figure 1 The automobile system circuit package provided by the embodiment of the application also comprises a power supply anti-reverse device 9.

[0067] For each control logic module, the first end of the MOSFET 2 of the module is connected with the power supply anti-reverse device 9, and the power supply anti-reverse device 9 is connected with the power supply 6 of the automobile.

[0068] In this way, the power supply anti-reverse device 9 is installed between the power supply 6 of the automobile and the MOSFET 2, so that the power supply is prevented from being connected reversely.

[0069] When the MCU works normally, the fault output circuit 1 has no output, the logic processing circuit 4 of each module is in a normal working state, and works normally according to the system instruction sent by the MCU.

[0070] When the fault output circuit 1 detects that the MCU has a fault, the fault signal enable signal is output to the signal detection circuit 3 and the logic processing circuit 4 of each control logic module.

[0071] For each control logic module, the signal detection circuit 3 of the module receives the fault signal enable signal, learns that the MCU has a fault, then switches from the normal working state to the limping mode state, and detects whether the one-key starting switch 8 is pressed.

[0072] The logic processing circuit 4 of the module receives the fault signal enable signal, learns that the MCU has a fault, then switches from the normal working state to the limping mode state, and shields the system signal sent by the MCU to prevent the error system signal from participating in the control.

[0073] When the signal detection circuit 3 of the group detects that the one-key start switch 8 is not pressed, it indicates that the vehicle needs to continue normal work at this time, and sends a takeover instruction to the latch circuit 5 of the group.

[0074] The latch circuit 5 of the group receives the takeover instruction sent by the signal detection circuit 3 of the group, at this time, the control of the logic processing circuit 4 of the group is taken over by the latch circuit 5 of the group, and the latch circuit 5 of the group sends the working state information of the MOSFET 2 of the group before the MCU fails to the logic processing circuit 4 of the group as the current working state information.

[0075] The logic processing circuit 4 of the group receives the current working state information sent by the latch circuit 5 of the group, and controls the MOSFET 2 of the group to be turned on or turned off based on the current working state information. If the current working state information is to turn on the MOSFET 2, the logic processing circuit 4 turns on the MOSFET 2 of the group, otherwise, it turns off the MOSFET 2 of the group. That is, when the one-key start switch 8 is not pressed, the latch circuit 5 of the group controls the working state of the MOSFET 2 of the group through the logic processing circuit 4 to remain the same as before the MCU fails, that is, to maintain the working state of the load 7 before the MCU fails, so as to ensure that the function of the load of the vehicle works normally without being affected by the MCU failure.

[0076] When the signal detection circuit 3 of the group detects that the one-key start switch 8 is pressed, it indicates that the vehicle needs to stop at this time, and needs to close the load 7 by turning off the MOSFET 2 of the group, so it sends a closing instruction to the latch circuit 5 of the group.

[0077] The latch circuit 5 of the group receives the closing instruction sent by the signal detection circuit 3 of the group, and sends the closing instruction to the logic processing circuit 4 of the group. The logic processing circuit 4 of the group receives the closing instruction sent by the latch circuit 5 of the group, and turns off the MOSFET 2 of the group. After the MOSFET 2 of the group is turned off, the load 7 connected with the MOSFET 2 is also turned off, so as to achieve the purpose of closing the load 7.

[0078] Since the MCU may be a short-time failure, when the fault output circuit 1 detects that the MCU has recovered to normal, it sends a stop detection instruction to each group of signal detection circuits 3 and a recovery control instruction to each group of logic processing circuits 4.

[0079] For each group of control logic modules, the signal detection circuit 3 of the group receives the stop detection instruction and stops detecting whether the one-key start switch 8 is pressed. The logic processing circuit 4 of the group receives the recovery control instruction and re-receives the system signal sent by the MCU, and continues to work normally according to the system instruction sent by the MCU.

[0080] Thus, after the fault output circuit 1 detects that the MCU has returned to normal, the signal detection circuit 3 of each group is controlled to stop detecting whether the one-key start switch 8 is pressed, and the logic processing circuit 4 of each group is controlled to continue to work normally according to the system instruction issued by the MCU, so that the vehicle works normally.

[0081] The automobile system circuit provided by the embodiment of the application supports switch-off and realizes limp-home mode, and comprises a fault output circuit 1 and at least one set of control logic modules, each set of control logic modules comprising a MOSFET 2, a signal detection circuit 3, a logic processing circuit 4 and a latch circuit 5, the signal detection circuit 3 and the logic processing circuit 4 of each set of control logic modules being in signal connection with the fault output circuit 1, the fault output circuit 1 also being in signal connection with the MCU of the automobile, for each set of control logic modules, the first end of the MOSFET 2 of the set being in signal connection with the power supply 6 of the automobile, the second end of the MOSFET 2 of the set being in signal connection with the logic processing circuit 4 of the set, the logic processing circuit 4 of the set being in signal connection with the MCU, the third end of the MOSFET 2 of the set being in signal connection with the load 7 of the automobile and the latch circuit 5 of the set respectively, the signal detection circuit 3 of the set being in signal connection with the one-key start switch 8 of the automobile and the latch circuit 5 of the set respectively, the latch circuit 5 of the set being in signal connection with the logic processing circuit 4 of the set, the fault output circuit 1 detecting the fault of the MCU and outputting a fault signal enable signal to the signal detection circuit 3 and the logic processing circuit 4 of each set of control logic modules, for each set of control logic modules, the signal detection circuit 3 of the set switching from a normal working state to a limp-home mode state after receiving the fault signal enable signal and detecting whether the one-key start switch 8 is pressed, the logic processing circuit 4 of the set switching from the normal working state to the limp-home mode state after receiving the fault signal enable signal and shielding the system signal sent by the MCU, when the signal detection circuit 3 of the set detects that the one-key start switch 8 is not pressed, sending a takeover instruction to the latch circuit 5 of the set, the latch circuit 5 of the set receiving the takeover instruction sent by the signal detection circuit 3 of the set, collecting the working state information of the MOSFET 2 of the set before the fault of the MCU occurs as current working state information and sending the current working state information to the logic processing circuit 4 of the set, the logic processing circuit 4 of the set receiving the current working state information sent by the latch circuit 5 of the set and controlling the MOSFET 2 of the set to be turned on or off based on the current working state information, when the signal detection circuit 3 of the set detects that the one-key start switch 8 is pressed, sending a shutdown instruction to the latch circuit 5 of the set, the latch circuit 5 of the set receiving the shutdown instruction sent by the signal detection circuit 3 of the set and sending the shutdown instruction to the logic processing circuit 4 of the set, and the logic processing circuit 4 of the set receiving the shutdown instruction sent by the latch circuit 5 of the set and shutting down the MOSFET 2 of the set.Therefore, in the embodiment of the present application, when the MCU enters the limp mode state due to failure and the one-key starting switch 8 is not pressed, the logic processing circuit 4 can be taken over by the latch circuit, so that the MOSFET 2 is controlled by the logic processing circuit 4 to maintain the working state before the MCU fails, that is, the working state of the load 7 before the MCU fails is maintained, so that the function of the load of the vehicle is ensured to work normally without being affected by the failure of the MCU, instead of starting the function of the load, thereby improving the safety of the vehicle. When the one-key starting switch 8 is pressed, the latch circuit 5 sends a shutdown instruction to the logic processing circuit 4, so that the MOSFET 2 is controlled by the logic processing circuit 4 to be turned off, that is, the load 7 is turned off, thereby avoiding the situation that the started function of the load cannot be turned off even after the vehicle is parked, and improving the convenience.

[0082] In addition, the automobile system circuit provided by the embodiment of the present application supports switch-off and realizes the limp mode, and is built by pure hardware, so that the labor cost is low and the development cycle is faster.

[0083] In addition, the automobile system circuit provided by the embodiment of the present application supports switch-off and realizes the limp mode, and is built by pure hardware, so that the labor cost is low and the development cycle is faster.

[0084] Figure 2 The structure diagram of the signal detection circuit provided by the embodiment of the present application is shown in Figure 2 Each group of signal detection circuits 3 includes a first resistor 31, a second resistor 32, a third resistor 33, a fourth resistor 34, a voltage comparator 35, a voltage source 36 and a first switch tube 37. For the voltage comparator 35, a high level is output when the positive voltage is greater than the negative voltage, and the first switch tube 37 can be an NPN triode or an NMOS (N-Metal-Oxide-Semiconductor) tube.

[0085] The one-key starting switch 8 is connected in parallel with the first resistor 31, one end of the first resistor 31 is grounded, the other end is connected with one end of the second resistor 32, the other end of the second resistor 32 is respectively connected with one end of the third resistor 33 and the comparison end of the voltage comparator 35, the other end of the third resistor 33 is connected with the fault output circuit 1, and the reference source end of the voltage comparator 35 is grounded through the voltage source 36, wherein the other end of the third resistor 33 is connected with the reference voltage end of the fault output circuit 1.

[0086] Continuing to refer to Figure 2One end of the fourth resistor 34 is connected to the fault output circuit 1, and the other end is connected to the positive power supply terminal of the voltage comparator 35 and the latch circuit 5 of the same group. The negative power supply terminal of the voltage comparator 35 is grounded. The output terminal of the voltage comparator 35 is connected to the first signal terminal of the first switching transistor 37. The output terminal of the first switching transistor 37 is connected to the latch circuit 5 of the same group. The second signal terminal of the first switching transistor 37 is grounded. One end of the fourth resistor 34 is connected to the fault voltage terminal of the fault output circuit 1.

[0087] The working principle of signal detection circuit 3 is as follows:

[0088] When the fault voltage is activated, that is, when the fault signal enable signal is received, the voltage comparator 35 starts to work. When the signal detection circuit 3 detects that the one-button start switch 8 is not pressed, the voltage at the comparison terminal of the voltage comparator 35 is greater than the voltage at the reference source terminal. The voltage comparator 35 outputs a high level to the latch circuit 5, that is, sends a takeover command to the latch circuit 5, thereby controlling the MOSFET2 to maintain the working state before the MCU malfunctions through the logic processing circuit 4.

[0089] When the signal detection circuit 3 detects that the one-button start switch 8 is pressed, the voltage at the comparison terminal of the voltage comparator 35 is less than the voltage at the reference source terminal. The voltage comparator 35 outputs a low level to the latch circuit 5, which means it sends a shutdown command to the latch circuit 5, thereby controlling the MOSFET 2 to turn off through the logic processing circuit 4.

[0090] Therefore, by setting the voltage comparator 35, when the one-button start switch 8 is not pressed, the voltage at the comparison terminal of the voltage comparator 35 is greater than the voltage at the reference source terminal, and the voltage comparator 35 outputs a high level to the latch circuit 5, that is, sends a takeover command to the latch circuit 5, thereby controlling the MOSFET2 to maintain the working state before the MCU malfunctions through the logic processing circuit 4. When the one-button start switch 8 is pressed, the voltage at the comparison terminal of the voltage comparator 35 is less than the voltage at the reference source terminal, and the voltage comparator 35 outputs a low level to the latch circuit 5, that is, sends a shutdown command to the latch circuit 5, thereby controlling the MOSFET2 to turn off through the logic processing circuit 4.

[0091] Figure 3 A schematic diagram of the logic processing circuit provided in an embodiment of the present invention is shown below. Figure 3 Each group's logic processing circuit 4 is a driver chip that supports level switching, SPI (Serial Peripheral Interface) control, and level control functions.

[0092] For example, the logic processing circuit 4 in each group can be a ROHM chip BD8LA700.

[0093] The level switching function refers to switching from a normal working state to a limp mode state after receiving a fault enable signal; the SPI control function refers to receiving or shielding a system signal sent by an MCU; and the level control function refers to being controllable by the latch module 5.

[0094] The working principle of the logic processing circuit 4 is as follows:

[0095] After receiving a fault signal enable signal, the logic processing circuit 4 switches from a normal working state to a limp mode state, shields a system signal sent by an MCU, receives current working state information sent by the latch circuit 5, and controls the MOSFET 2 to be turned on or turned off based on the current working state information. After the MCU recovers to normal, the logic processing circuit 4 receives a recovery control instruction, re-receives the system signal sent by the MCU, and continues to work normally according to the system instruction sent by the MCU.

[0096] Thus, by using a driving chip supporting a level switching function, an SPI control function, and a level control function, the logic processing circuit 4 switches from a normal working state to a limp mode state after receiving a fault signal enable signal, shields a system signal sent by an MCU, receives current working state information sent by the latch circuit 5, and controls the MOSFET 2 to be turned on or turned off based on the current working state information. After the MCU recovers to normal, the logic processing circuit 4 receives a recovery control instruction, re-receives the system signal sent by the MCU, and continues to work normally according to the system instruction sent by the MCU.

[0097] In an implementation manner, the latch circuit 5 of each group is further connected with an MCU signal.

[0098] The MCU sends an activation instruction to the latch circuit 5 of each group to activate the latch circuit 5 when the vehicle starts.

[0099] To ensure that the latch circuit 5 of each group can work normally, the MCU sends an activation instruction to the latch circuit 5 of each group to activate the latch circuit when the vehicle starts.

[0100] Figure 4 The latch circuit provided by the embodiment of the present application is shown in the structural diagram, which is shown in Figure 4 In the case that the latch circuit 5 of each group is further connected with an MCU signal, the latch circuit 5 of each group comprises a NOT gate 51, a first OR gate 52, a first diode 53, a second diode 54, and a tri-state single buffer gate 55.

[0101] The input end of the non-gate 51 is connected with the MOSFET 2 signal of the group, the output end of the non-gate 51 is connected with the first input end of the first or-gate 52, the second input end of the first or-gate 52 is connected with the signal detection circuit 3 of the group, the output end of the first or-gate 52 is connected with the output enable end of the tri-state single buffer gate 55, the positive pole of the first diode 53 is connected with the MCU, the negative pole of the first diode 53 is connected with the negative pole of the second diode 54 and the input end of the tri-state single buffer gate 55 respectively, the output end of the tri-state single buffer gate 55 is connected with the logic processing circuit 4 of the group, and the positive pole of the second diode 54 is connected with the logic processing circuit 4 of the group.

[0102] For the tri-state single buffer gate 55, when the output enable end is low, the output end follows the level state of the output enable end and is also low, and when the output enable end is high, the output end is in a high resistance state and has no output.

[0103] The working principle of the latch circuit 5 is as follows:

[0104] When the closing instruction is low and the driving output state, that is, the working state of the MOSFET 2, is high, the first or-gate 52 outputs low, the MCU inputs a high signal to the tri-state single buffer gate 55 according to the current working state, the tri-state single buffer gate 55 outputs a high working state to the logic processing circuit 4, that is, the latch circuit 5 receives the takeover instruction sent by the signal detection circuit 3, and the latch circuit 5 collects the working state information of the MOSFET 2 before the MCU fails as the current working state information and sends it to the logic processing circuit 4.

[0105] When the closing instruction is pulled high or the driving output is closed, that is, the MOSFET 2 is closed and is low, the first or-gate 52 outputs high to the output enable end of the tri-state single buffer gate 55, at this time, the output end of the tri-state single buffer gate 55 is in a high resistance state, and since the working state of the driving output, that is, the MOSFET 2, is controlled by the working state of the tri-state single buffer gate 55, the working state of the driving output, that is, the MOSFET 2, is low, the high level of the output enable end of the tri-state single buffer gate 55 is maintained, and the low level of the output working state of the tri-state single buffer gate 55 is maintained to the logic processing circuit 4, that is, the latch circuit 5 receives the closing instruction sent by the signal detection circuit 3 and sends the closing instruction to the logic processing circuit 4.

[0106] Thus, by setting the three-state single-buffer gate 55, the latch circuit 5 receives the takeover instruction sent by the signal detection circuit 3, collects the working state information of the MOSFET 2 before the MCU fails as the current working state information and sends the current working state information to the logic processing circuit 4, and then controls the working state of the MOSFET 2 to be the same as that before the MCU fails, so as to ensure that the vehicle normally works without being affected by the MCU failure, and to realize that the latch circuit 5 receives the shutdown instruction sent by the signal detection circuit 3 and sends the shutdown instruction to the logic processing circuit 4, and then the MOSFET 2 is turned off, so as to achieve the purpose of turning off the load 7.

[0107] Figure 5 The structure schematic diagram of the fault output circuit 1 provided by the embodiment of the application is shown in Figure 5 The fault output circuit 1 comprises an NOR gate 11 and a second switch tube 12. The second switch tube 12 can be a PNP triode or a PMOS (positive channel Metal Oxide Semiconductor, p-channel metal oxide semiconductor) tube.

[0108] The first input end of the NOR gate 11 is connected with the MCU signal, the output end of the NOR gate 11 is connected with the first signal end of the second switch tube 12, the second signal end of the second switch tube 12 is connected with the key electric relay 10 of the automobile, and the output end of the second switch tube 12 is connected with the signal detection circuit 3 and the logic processing circuit 4 of each group, respectively.

[0109] The working principle of the fault output circuit 1 is as follows:

[0110] When the key electric relay 10 normally outputs the key electric and the fault signal output by the MCU is high, the NOR gate 11 outputs low, the second switch tube 12 is opened, the second switch tube 12 outputs the fault enable signal as high, that is, the fault output circuit 1 detects that the MCU fails, and outputs the fault signal enable signal to the signal detection circuit 3 and the logic processing circuit 4, respectively.

[0111] If there is no key electric or the MCU does not output the fault signal, the second switch tube 12 outputs the fault enable signal as low, that is, the MCU does not fail, and no fault signal enable signal is output at this time.

[0112] Thus, by setting the NOR gate 11 and the second switch tube 12, it is realized that the fault output circuit 1 detects that the MCU fails, and outputs the fault signal enable signal to the signal detection circuit 3 and the logic processing circuit 4, respectively.

[0113] Continuously referring to Figure 5The second input end and the third input end of the NOR gate 11 are both connected with the power supply 6 of the automobile, and the second input end is connected with the overvoltage fault end of the power supply 6, and the third input end is connected with the undervoltage fault end of the power supply 6.

[0114] When the key electric relay 10 normally outputs the key electric and the overvoltage signal / undervoltage signal output by the power supply 6 is high, the NOR gate 11 outputs low, the second switch tube 12 is opened, and the power supply fault signal output by the second switch tube 12 is high, that is, the fault output circuit 1 detects that the power supply has overvoltage fault / undervoltage fault, and outputs the power supply fault signal to the signal detection circuit 3 and the logic processing circuit 4 respectively.

[0115] The subsequent process is the same as the process when the MCU fails, and will not be described here.

[0116] Therefore, by connecting the second input end of the NOR gate 11 with the overvoltage fault end of the power supply 6 of the automobile, and connecting the third input end of the NOR gate 11 with the undervoltage fault end of the power supply 6 of the automobile, the load 7 is closed when the power supply 6 has overvoltage fault or undervoltage fault.

[0117] Figure 6 A structural schematic diagram of an automobile provided by the embodiment of the present application is provided in Figure 6 The automobile provided by the embodiment of the present application comprises an automobile system circuit 20 and a vehicle body 21, the automobile system circuit 20 is installed on the vehicle body 21, and the automobile system circuit 20 is the automobile system circuit provided by any one of the above embodiments and supports the switch-off and realizes the limp-home mode.

[0118] Thus, the automobile provided by the embodiment of the application comprises an automobile system circuit 20 and a vehicle body 21, the automobile system circuit 20 is installed on the vehicle body 21, the automobile system circuit 20 comprises a fault output circuit 1 and at least one set of control logic modules, each set of control logic modules comprises a MOSFET 2, a signal detection circuit 3, a logic processing circuit 4 and a latch circuit 5, the signal detection circuit 3 and the logic processing circuit 4 of each set of control logic modules are in signal connection with the fault output circuit 1, the fault output circuit 1 is also in signal connection with an MCU of the automobile, for each set of control logic modules, a first end of the MOSFET 2 of the set is in signal connection with a power supply 6 of the automobile, a second end of the MOSFET 2 of the set is in signal connection with the logic processing circuit 4 of the set, the logic processing circuit 4 of the set is in signal connection with the MCU, a third end of the MOSFET 2 of the set is in signal connection with a load 7 of the automobile and the latch circuit 5 of the set respectively, the signal detection circuit 3 of the set is in signal connection with a one-key starting switch 8 of the automobile and the latch circuit 5 of the set respectively, the latch circuit 5 of the set is in signal connection with the logic processing circuit 4 of the set, the fault output circuit 1 detects that the MCU is faulty, and outputs a fault signal enable signal to the signal detection circuit 3 and the logic processing circuit 4 of each set of control logic modules, for each set of control logic modules, the signal detection circuit 3 of the set switches from a normal working state to a limping mode state after receiving the fault signal enable signal, and detects whether the one-key starting switch 8 is pressed, the logic processing circuit 4 of the set switches from the normal working state to the limping mode state after receiving the fault signal enable signal, and shields a system signal sent by the MCU, when the signal detection circuit 3 of the set detects that the one-key starting switch 8 is not pressed, sends a takeover instruction to the latch circuit 5 of the set, the latch circuit 5 of the set receives the takeover instruction sent by the signal detection circuit 3 of the set, collects working state information of the MOSFET 2 of the set before the MCU is faulty as current working state information and sends the current working state information to the logic processing circuit 4 of the set, the logic processing circuit 4 of the set receives the current working state information sent by the latch circuit 5 of the set, and controls the MOSFET 2 of the set to be turned on or turned off based on the current working state information, when the signal detection circuit 3 of the set detects that the one-key starting switch 8 is pressed, sends a closing instruction to the latch circuit 5 of the set, the latch circuit 5 of the set receives the closing instruction sent by the signal detection circuit 3 of the set, and sends the closing instruction to the logic processing circuit 4 of the set, the logic processing circuit 4 of the set receives the closing instruction sent by the latch circuit 5 of the set, and closes the MOSFET 2 of the set.Thus, in the embodiment of the present application, when the MCU enters the limp mode state due to a fault and the one-key starting switch 8 is not pressed, the latch circuit can take over the logic processing circuit 4, so that the MOSFET 2 is controlled by the logic processing circuit 4 to maintain the working state before the MCU fails, that is, the working state of the load 7 before the MCU fails, so as to ensure that the function of the load of the vehicle works normally without being affected by the MCU fault, instead of starting the function of the load, thereby improving the safety of the vehicle. When the one-key starting switch 8 is pressed, the latch circuit 5 sends a closing instruction to the logic processing circuit 4, so that the MOSFET 2 is controlled by the logic processing circuit 4 to be closed, that is, the load 7 is closed, thereby avoiding the situation that the function of the started load cannot be closed even after the vehicle is parked, and improving the convenience.

[0119] Those skilled in the art can understand that the drawings are only schematic diagrams of an embodiment, and the modules or flows in the drawings are not necessarily necessary for implementing the present application.

[0120] Those skilled in the art can understand that the modules in the device in the embodiment can be distributed in the device in the embodiment according to the description of the embodiment, or can be changed and located in one or more devices different from the embodiment. The modules in the above embodiment can be combined into one module, or can be further split into multiple sub-modules.

[0121] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for some technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A vehicle system circuit that supports switch-off and implements limp mode, characterized in that, include: The fault output circuit and at least one set of control logic modules, each set of control logic modules including a metal-oxide-semiconductor field-effect transistor (MOSFET), a signal detection circuit, a logic processing circuit, and a latch circuit; The signal detection circuit and logic processing circuit of each group of control logic modules are connected to the fault output circuit, and the fault output circuit is also connected to the microcontroller unit (MCU) of the vehicle. For each control logic module, the first terminal of the MOSFET in the group is connected to the power signal of the vehicle, the second terminal of the MOSFET in the group is connected to the signal of the logic processing circuit in the group, the logic processing circuit in the group is connected to the signal of the MCU, the third terminal of the MOSFET in the group is connected to the load of the vehicle and the signal of the latch circuit in the group, the signal detection circuit in the group is connected to the one-button start switch of the vehicle and the signal of the latch circuit in the group, and the latch circuit in the group is connected to the signal of the logic processing circuit in the group. The fault output circuit detects that the MCU has failed and outputs a fault signal enable signal to the signal detection circuit and logic processing circuit of each group of control logic modules respectively. For each group of control logic modules, the signal detection circuit of that group switches from normal working state to limp mode state after receiving the fault signal enable signal, and detects whether the one-key start switch is pressed. After receiving the fault signal enable signal, the logic processing circuit of this group switches from normal operation to limp mode and blocks the system signals sent by the MCU. When the signal detection circuit of the group detects that the one-key start switch has not been pressed, it sends a takeover command to the latching circuit of the group. The latching circuit of this group receives the takeover command sent by the signal detection circuit of this group, and collects the working status information of the MOSFET of this group before the MCU malfunctions and sends it as the current working status information to the logic processing circuit of this group. The logic processing circuit of this group receives the current operating status information sent by the latch circuit of this group, and controls the MOSFET of this group to turn on or off based on the current operating status information; When the signal detection circuit of the group detects that the one-key start switch is pressed, it sends a shutdown command to the latching circuit of the group. The latch circuit of this group receives the shutdown command sent by the signal detection circuit of this group, and sends the shutdown command to the logic processing circuit of this group. The logic processing circuit of this group receives a shutdown command from the latch circuit of this group and shuts down the MOSFET of this group; After the fault output circuit detects that the MCU has returned to normal, it sends a stop detection command to the signal detection circuit of each group and a recovery control command to the logic processing circuit of each group. For each group of control logic modules, the signal detection circuit of that group stops detecting whether the one-button start switch has been pressed after receiving the stop detection command; After receiving the recovery control command, the logic processing circuit of this group will again receive the system signals sent by the MCU.

2. The automotive system circuit that supports switch-off and implements limp mode as described in claim 1, characterized in that, It also includes a power supply reverse protection device; For each group of control logic modules, the first terminal of the MOSFET in that group is connected to the power supply anti-reverse signal, and the power supply anti-reverse signal is connected to the power supply signal of the vehicle.

3. The automotive system circuit that supports switch-off and implements limp mode as described in claim 1, characterized in that, Each group's signal detection circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a voltage comparator, a voltage source, and a first switching transistor; The one-button start switch is connected in parallel with the first resistor. One end of the first resistor is grounded, and the other end is connected to one end of the second resistor. The other end of the second resistor is connected to one end of the third resistor and the comparison terminal of the voltage comparator. The other end of the third resistor is connected to the fault output circuit. The reference source terminal of the voltage comparator is grounded through the voltage source. One end of the fourth resistor is connected to the fault output circuit signal, and the other end is connected to the positive power supply terminal of the voltage comparator and the latch circuit signal of the group respectively. The negative power supply terminal of the voltage comparator is grounded. The output terminal of the voltage comparator is connected to the first signal terminal of the first switch transistor. The output terminal of the first switch transistor is connected to the latch circuit signal of the group. The second signal terminal of the first switch transistor is grounded.

4. The automotive system circuit that supports switch-off and implements limp mode as described in claim 1, characterized in that, Each group's logic processing circuit is a driver chip that supports level switching, serial peripheral interface (SPI) control, and level control functions.

5. The automotive system circuit that supports switch-off and implements limp mode as described in claim 1, characterized in that, Each group's latching circuit is also connected to the MCU signal; When the car starts, the MCU sends an activation command to each group of latch circuits to activate each latch circuit.

6. The automotive system circuit as described in claim 5, which supports switch shutdown and implements limp mode, is characterized in that... Each group of latching circuits includes a NOT gate, a first OR gate, a first diode, a second diode, and a tri-state single-buffer gate; The input terminal of the NOT gate is connected to the MOSFET signal of the group, the output terminal of the NOT gate is connected to the first input terminal signal of the first OR gate, the second input terminal of the first OR gate is connected to the signal detection circuit signal of the group, the output terminal of the first OR gate is connected to the output enable terminal signal of the tri-state single-buffered gate, the anode of the first diode is connected to the MCU signal, the cathode of the first diode is connected to the cathode of the second diode and the input terminal signal of the tri-state single-buffered gate, the output terminal of the tri-state single-buffered gate is connected to the logic processing circuit signal of the group, and the anode of the second diode is connected to the logic processing circuit signal of the group.

7. The automotive system circuit as described in claim 1, which supports switch-off and implements limp mode, is characterized in that... The fault output circuit includes a NOR gate and a second switching transistor. The first input terminal of the NOR gate is connected to the MCU signal, the output terminal of the NOR gate is connected to the first signal terminal of the second switch, the second signal terminal of the second switch is connected to the key relay signal of the car, and the output terminal of the second switch is connected to the signal detection circuit and logic processing circuit of each group respectively.

8. The automotive system circuit as described in claim 7, which supports switch shutdown and implements limp mode, is characterized in that, The second input of the NOR gate is connected to the overvoltage fault signal of the vehicle's power supply, and the third input of the NOR gate is connected to the undervoltage fault signal of the vehicle's power supply.

9. A car, characterized in that, It includes an automotive system circuit and a vehicle body, wherein the automotive system circuit is installed on the vehicle body, and the automotive system circuit is the automotive system circuit that supports switch-off and implements limp mode as described in any one of claims 1-8.

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