A body controller fault control circuit and a body control system

Abstract

A body controller fault control circuit and a body control system according to the present invention include: a limp home signal generation circuit connected to an MCU control unit for generating a limp home enable signal when the MCU control unit fails; a fail-safe control circuit connected to the limp home signal generation circuit and a vehicle ignition switch respectively to generate a fail-safe control signal; a first lighting turn-on circuit connected to the fail-safe control circuit to control the lighting turn-on; a first switch control load turn-on circuit connected to the fail-safe control circuit and a load control switch respectively for generating a load control signal according to the fail-safe control signal and the switch signal of the load control switch, and based on the load control signal, controlling the corresponding load to turn on through a first relay. When the MCU control unit fails, the present invention can timely turn on functions such as vehicle lights and wipers, ensuring the safety of its own vehicle and reminding surrounding vehicles.

Description

Technical Field

[0001] The present invention relates to the field of automobiles, and particularly to a body controller fault control circuit and a body control system. Background Art

[0002] An automotive limp-home control circuit is for the reliable control of certain important functions (such as loads like lights and wipers), to prevent the loss of important functions due to a failure of the MCU control unit and thus affect the driving safety of the vehicle. In the prior art, when the MCU control unit fails, generally a watchdog is used to restart the MCU control unit. When the watchdog does not receive the feeding signal from the MCU control unit, the watchdog resets the MCU control unit by a reset method. This processing method has the following problems: If the MCU control unit has been burned out or short-circuited, this method will fail, resulting in the inability to turn on loads such as lights and / or wipers. If the lights and / or wipers and other loads cannot be turned on, the safety of the driver of the faulty vehicle cannot be guaranteed. Therefore, it is necessary to design a control circuit that can directly enter the limp-home control mode after the reset of the MCU control unit fails. Summary of the Invention

[0003] The main object of the present invention is to propose a body controller fault control circuit and a body control system, which can turn on functions such as vehicle lights and wipers when the MCU control unit fails, to ensure the safety of the vehicle itself and to remind surrounding vehicles.

[0004] The present invention adopts the following technical solutions:

[0005] On the one hand, a body controller fault control circuit includes:

[0006] A limp-home signal generation circuit, connected to the MCU control unit, for generating a limp-home enable signal when the MCU control unit fails;

[0007] A fail-safe control circuit, connected to the limp-home signal generation circuit and the vehicle ignition switch respectively, for generating a fail-safe control signal according to the limp-home enable signal and the ignition signal of the vehicle ignition switch;

[0008] A first light turning-on circuit, connected to the fail-safe control circuit, for controlling the turning-on of lights according to the fault start signal;

[0009] A first switch control load turning-on circuit, connected to the fail-safe control circuit and the load control switch respectively, for generating a load control signal according to the fail-safe control signal and the switch signal of the load control switch; based on the load control signal, controlling the corresponding load to turn on through a first relay.

[0010] Preferably, the limp-home signal generation circuit includes a system basis chip (SBC); the SBC is connected to the MCU control unit and generates a limp-home enable signal after detecting a fault in the MCU control unit.

[0011] Preferably, the fail-safe control circuit includes a first triode, a second triode, and a third triode; the second triode is respectively connected to the first triode and the third triode; the first triode is connected to the limp-home enable signal, the ignition signal, and the DC power supply respectively; the third triode is connected to the ignition signal; the limp-home enable signal, the ignition signal, and the DC power supply control the working states of the first triode and the second triode, and the ignition signal controls the working state of the third triode.

[0012] Preferably, the first light turning-on circuit includes an intelligent MOS chip; the input end of the intelligent MOS chip is connected to the fail-safe control signal, and the output end of the intelligent MOS chip is connected to the light.

[0013] Preferably, the first light turning-on circuit further includes a first diode, and the first diode is arranged between the fail-safe control signal and the intelligent MOS chip.

[0014] Preferably, the first switch control load turning-on circuit includes a fourth triode and a relay driver chip; the fourth triode is respectively connected to the fail-safe control signal and the switch signal, and the fail-safe control signal and the switch signal control the working state of the fourth triode; the input end of the relay driver chip is connected to the output signal of the fourth triode, the output end of the relay driver chip is connected to the first relay, and the first relay controls the working state of the load.

[0015] Preferably, the first switch control load turning-on circuit further includes a second diode; the second diode is arranged between the switch signal and the fourth triode.

[0016] Preferably, the first switch control load turning-on circuit further includes a third diode; the third diode is arranged between the fourth triode and the relay driver chip.

[0017] On the other hand, a vehicle body control system includes an MCU control unit and further includes the vehicle body controller fault control circuit as described above.

[0018] Preferably, the vehicle body control system further includes a vehicle body controller normal control circuit; the vehicle body controller normal control circuit includes:

[0019] The second lighting turn-on circuit, connected to the MCU control unit, is configured to receive the lighting control signal sent by the MCU control unit through an intelligent MOS chip and control the lighting to turn on or off according to the lighting control signal;

[0020] The second switch control load turn-on circuit, connected to the MCU control unit, is configured to receive the load control signal sent by the MCU control unit through a relay driver chip and drive the second relay to act according to the load control signal, and the second relay controls the working state of the connected load.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] (1) When a limp home enable signal is output in case of a fault in the MCU control unit, if the vehicle has been ignited at this time, the control outputs a fail-safe control signal through a triode; based on the fail-safe control signal, on the one hand, it directly controls the lighting (such as hazard warning lights, low beam lights, etc.) to turn on, so that whether the fault occurs at night or during the day, it can play a reminder role and ensure the safety of the driver and surrounding vehicles / persons; on the other hand, according to the needs of the driver, after the driver turns on the load control switch (such as the wiper control switch), it can also control the load to act at a preset frequency, which can not only play a reminder role, but also ensure the driver's visual space on rainy days and further ensure the driver's safety;

[0023] (2) The present invention controls the output of the fail-safe control signal only when both conditions of generating a limp home enable signal and the vehicle being ignited are met, preventing the lighting and other loads from being turned on when the vehicle is not ignited, resulting in waste of resources and shortening the service life of equipment (such as lighting and wipers);

[0024] (3) The first lighting turn-on circuit and the second lighting turn-on circuit of the present invention share the same intelligent MOS chip, and the first switch control load turn-on circuit and the second switch control load turn-on circuit share the same relay driver chip. Through the reuse of components, the unified layout of the body controller fault control circuit and the body controller normal control circuit is realized. On the one hand, it saves costs, and on the other hand, it makes the circuit wiring reasonable and simple, reducing the coupling between components.

[0025] The above description is only an overview of the technical solution of the present invention. In order to be able to understand the technical means of the present invention more clearly, so as to be implemented in accordance with the content of the specification, and in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable, the following specific embodiments of the present invention are listed.

[0026] Those skilled in the art will better understand the above and other objects, advantages, and features of the present invention from the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings. Brief Description of the Drawings

[0027] Figure 1 It is the overall structural block diagram of the body controller fault control circuit according to an embodiment of the present invention;

[0028] Figure 2 It is the overall circuit diagram according to an embodiment of the present invention;

[0029] Figure 3 It is the limp-home signal generation circuit according to an embodiment of the present invention;

[0030] Figure 4 It is the fail-safe control circuit according to an embodiment of the present invention;

[0031] Figure 5 It is the light-on circuit according to an embodiment of the present invention;

[0032] Figure 6 It is the switch control load turn-on circuit I according to an embodiment of the present invention;

[0033] Figure 7 It is the switch control load turn-on circuit II according to an embodiment of the present invention;

[0034] Figure 8 It is the overall structural block diagram of the body control system according to an embodiment of the present invention. Detailed Embodiments

[0035] In order to make the technical solutions and advantages of the present invention clearer and more understandable, the following further details the present invention in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for illustrative purposes of the present invention and are not used to limit the protection scope of the present invention.

[0036] For the sake of brevity and intuitiveness in description, the following describes the solutions of the present invention by describing several representative embodiments. A large number of details in the embodiments are only used to help understand the solutions of the present invention. However, it is obvious that the technical solutions of the present invention can be implemented without being limited to these details. In order to avoid unnecessarily obscuring the solutions of the present invention, some embodiments are not described in detail but only present the framework. Hereinafter, "including" means "including but not limited to", and "according to..." means "at least according to..., but not limited to only according to...". Due to the language habits of Chinese, when the number of a component is not specifically pointed out hereinafter, it means that the component can be one or more, or can be understood as at least one.

[0037]

[0038] Figure 1 See Figure 1as shown Figure 2 As shown in Figure 2 , a vehicle body controller fault control circuit 10 of the present invention includes:

[0039] A limp signal generation circuit 101, connected to the MCU control unit 20, for generating a limp home enable signal LIMP_HOME when the MCU control unit 20 fails;

[0040] A fail-safe control circuit 102, connected to the limp home enable signal LIMP_HOME generation circuit and the vehicle ignition switch respectively, for generating a fail-safe control signal FAIL_SAFE according to the limp home enable signal LIMP_HOME and the ignition signal IGN of the vehicle ignition switch;

[0041] A first lighting turn-on circuit 103, connected to the fail-safe control circuit 102, for controlling the lighting to turn on according to the fault start signal;

[0042] A first switch control load turn-on circuit 104, connected to the fail-safe control circuit 102 and the load control switch respectively, for generating a load control signal WIP_FAILSAFE according to the fail-safe control signal FAIL_SAFE and the switch signal SW of the load control switch; based on the load control signal WIP_FAILSAFE, controlling the corresponding load to turn on through a first relay RLY1.

[0043] Specifically, referring to Figure 3 As shown, the limp signal generation circuit 101 includes a system basic chip SBC (U1); the system basic chip SBC (U1) is connected to the MCU control unit 20, and generates a limp home enable signal LIMP_HOME after detecting the failure of the MCU control unit 20. In this embodiment, the model of the system basic chip is UJA1078. The UJA1078 includes a watchdog circuit, which can monitor the working state of the MCU control unit 20, generate a limp home enable signal LIMP_HOME after detecting the failure of the MCU control unit 20, and output the LIMP_HOME signal to the fail-safe control circuit 102 through the LIMP pin. In this embodiment, the limp home enable signal LIMP_HOME is a low-level signal.

[0044] Referring to Figure 4As shown, the fail-safe control circuit 102 includes a first triode Q1, a second triode Q2, and a third triode Q3; the second triode Q2 is respectively connected to the first triode Q1 and the third triode Q3; the first triode Q1 is respectively connected to the limp-home signal LIMP_HOME, the ignition signal IGN, and the DC power supply; the third triode Q3 is connected to the ignition signal IGN; the limp-home signal LIMP_HOME, the ignition signal IGN, and the DC power supply control the working states of the first triode Q1 and the second triode Q2, and the ignition signal IGN controls the working state of the third triode Q3.

[0045] Specifically, the first triode Q1 includes an NPN type triode or a PNP type triode; the second triode Q2 includes an NPN type triode or a PNP type triode; the third triode Q3 includes an NPN type triode or a PNP type triode. In this embodiment, the first triode Q1 is set as a PNP type triode, the second triode Q2 is set as a PNP type triode, and the third triode Q3 is set as an NPN type triode. The ignition signal IGN and the 5V DC power supply are connected to the emitter of the first triode Q1 through a resistor, the limp-home signal LIMP_HOME is connected to the base of the first triode Q1 through a resistor, the collector of the first triode Q1 is connected to the emitter of the second triode Q2, and the collector of the second triode Q2 outputs the fail-safe control signal FAIL_SAFE. The base of the second triode Q2 is connected to the collector of the third triode Q3 through a resistor, the ignition signal IGN is connected to the base of the third triode Q3 through a second zener diode and a resistor, and the emitter of the third triode Q3 is grounded.

[0046] In this embodiment, only when the MCU control unit 20 fails and the vehicle is ignited, the second triode Q2 will conduct and output the fail-safe control signal FAIL_SAFE. Specifically, when the MCU control unit 20 fails to work properly, the limp-home signal LIMP_HOME is triggered. When the vehicle ignition signal IGN is turned on, the limp-home signal LIMP_HOME drives the first triode Q1 to conduct the 5V power supply, drives the second triode Q2 to conduct, and outputs a high-level fail-safe control signal FAIL_SAFE. When the MCU control unit 20 resumes normal operation, the limp-home signal LIMP_HOME is not output, and the MCU control unit fault control circuit 10 is turned off.

[0047] See Figure 5As shown, the first lighting turn-on circuit 103 includes an intelligent MOS chip U2; the input end of the intelligent MOS chip U2 is connected to the fail-safe control signal FAIL_SAFE, and the output end of the intelligent MOS chip U2 is connected to the lighting. In this embodiment, the model of the intelligent MOS chip U2 is BTS7010-1EPA. The input pin IN of the intelligent MOS chip U2 is respectively connected to the fail-safe control signal FAIL_SAFE and the lighting control signal sent by the MCU control unit 20. When the MCU control unit 20 fails, the input pin IN of the intelligent MOS chip U2 is controlled by the fail-safe control signal FAIL_SAFE. The output pin OUT of the intelligent MOS chip U2 controls the turn-on of the lighting according to the input pin IN.

[0048] In this embodiment, the first lighting turn-on circuit 103 further includes a first diode Q1, and the first diode Q1 is arranged between the fail-safe control signal FAIL_SAFE and the intelligent MOS chip U2. Arranging the first diode Q1 between the fail-safe control signal FAIL_SAFE and the intelligent MOS chip U2 can ensure that the fail-safe control signal FAIL_SAFE is input to the input pin IN of the intelligent MOS chip U2 only when the fail-safe control signal FAIL_SAFE takes a high level.

[0049] See Figure 6 and Figure 7 As shown, the first switch control load turn-on circuit 104 includes a fourth triode Q4 and a relay driver chip U3; the fourth triode Q4 is respectively connected to the fail-safe control signal FAIL_SAFE and the switch signal SW, and the fail-safe control signal FAIL_SAFE and the switch signal SW control the working state of the fourth triode Q4; the input end of the relay driver chip U3 is connected to the output signal of the fourth triode Q4, the output end of the relay driver chip U3 is connected to the first relay RLY1, and the first relay RLY1 controls the working state of the load.

[0050] Specifically, the fourth triode Q4 includes a PNP type triode or an NPN type triode. In this embodiment, the fourth triode Q4 is a PNP type triode.

[0051] The switch information is the switch signal SW generated by an external manual control switch. When the driver controls the switch to close, the switch signal SW outputs a low level signal, and when the switch is not closed, the switch signal SW outputs a high level signal.

[0052] The first switch control load turn-on circuit 104 further includes a second diode Q2; the second diode Q2 is disposed between the switch signal SW and the fourth triode Q4.

[0053] The first switch control load turn-on circuit 104 further includes a third diode Q3; the third diode Q3 is disposed between the fourth triode Q4 and the relay driver chip U3.

[0054] The switch signal SW is connected to the base of the fourth triode Q4 through the second diode Q2. The fail-safe control signal FAIL_SAFE is connected to the emitter of the fourth triode Q4, and the collector of the fourth triode Q4 outputs a load control signal WIP_FAILSAFE.

[0055] The second diode Q2 disposed between the switch signal SW and the fourth triode Q4 can ensure that only when the external manual control switch is closed, the fourth triode Q4 is controlled to conduct and output the load control signal WIP_FAILSAFE.

[0056] Further, the model of the relay driver chip U3 is ULN2003AFW. The first input terminal of the relay driver chip U3 is respectively connected to the load control signal WIP_FAILSAFE and the first load control signal FR_WIPER_LOW sent when the MCU control unit works normally. The third diode Q3 disposed between the fourth triode Q4 and the relay driver chip U3 ensures that only when the load control signal WIP_FAILSAFE is at a high level, the load control signal WIP_FAILSAFE is input to the first input pin I1. When the load control signal WIP_FAILSAFE is at a high level, it is connected to the output pin O1 of the relay driver chip U3 to control the first relay RLY1 to be connected to the FR_WIPER_PER terminal, so as to control the corresponding load to start according to the set rules.

[0057] In this embodiment, the load may be a wiper device. For load devices such as wipers, if they are directly started when the MCU control unit fails, it may affect the driver's senses, such as affecting hearing and vision. Therefore, a different control method from the lighting control is required, that is, it is only turned on after the driver actively closes the load control switch.

[0058] See Figure 8 As shown, on the other hand, a vehicle body control system includes an MCU control unit 20 and further includes the vehicle body controller fault control circuit 10.

[0059] Further, the vehicle body control system further includes a normal vehicle body controller control circuit 30; the normal vehicle body controller control circuit 30 includes:

[0060] A second lighting turn-on circuit, connected to the MCU control unit 20, for receiving the lighting control signal sent by the MCU control unit 20 through the intelligent MOS chip U2, and controlling the lighting to turn on or off according to the lighting control signal;

[0061] A second switch control load turn-on circuit, connected to the MCU control unit 20, for receiving the load control signal WIP_FAILSAFE sent by the MCU control unit 20 through the relay driver chip U3, and driving the second relay RLY2 to act according to the load control signal WIP_FAILSAFE, and the second relay RLY2 controls the working state of the connected load.

[0062] It should be noted that the second lighting turn-on circuit shares an intelligent MOS chip U2 with the first lighting turn-on circuit 103, and the second switch control load turn-on circuit shares a relay driver chip U3 with the first switch control load turn-on circuit 104. For the specific lighting control signal, please refer to Figure 5 the MCU_INFO signal in Figure 6 In , when the MCU control unit works normally, it will first convert the switch signal SW into the FRONT_WIPER_LO_AD signal and input it into the MCU control unit. After the MCU control unit determines whether it is a high-level or low-level signal, it outputs it to Figure 7 the I1 pin (FR_WIPER_LOW) or the I2 pin (FR_WIPER_HI) of the relay driver chip U3 shown in , thereby controlling the second relay RLY2. Through the reuse of components, the unified layout of the vehicle body controller fault control circuit and the normal vehicle body controller control circuit is realized. On the one hand, the cost is saved, and on the other hand, the circuit wiring is reasonable and simple, reducing the coupling between components.

[0063] The above is only the specific implementation manner of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantive modification made to the present invention using this concept shall fall within the scope of infringement of the protection of the present invention.

Claims

1. A vehicle body controller fault control circuit, characterized in that, it includes: A limp home signal generation circuit, connected to the MCU control unit, for generating a limp home enable signal when the MCU control unit fails; A fail-safe control circuit, connected to the limp home signal generation circuit and the vehicle ignition switch respectively, for generating a fail-safe control signal according to the limp home enable signal and the ignition signal of the vehicle ignition switch; A first lighting turn-on circuit, connected to the fail-safe control circuit, for controlling the lighting to turn on according to the fail-safe control signal; A first switch control load turn-on circuit, connected to the fail-safe control circuit and the load control switch respectively, for generating a load control signal according to the fail-safe control signal and the switch signal of the load control switch; Based on the load control signal, control the corresponding load to turn on through a first relay; The fail-safe control circuit includes a first triode, a second triode, a third triode and an eighty-fifth resistor; the second triode is connected to the first triode and the third triode respectively; the first triode is connected to the limp home enable signal, the ignition signal and the DC power supply respectively; the third triode is connected to the ignition signal; the limp home enable signal, the ignition signal and the DC power supply control the working states of the first triode and the second triode, and the ignition signal controls the working state of the third triode; Specifically, the ignition signal and the 5V DC power supply are respectively connected to the emitter of the first triode through an eighty-third resistor and a two-hundred-and-sixty-ninth resistor, the limp home enable signal is connected to the base of the first triode through an eighty-ninth resistor, and the collector of the first triode is connected to the emitter of the second triode; one end of the eighty-fifth resistor is connected to the connection point of the collector of the first triode and the emitter of the second triode, and the other end of the eighty-fifth resistor is grounded; the collector of the second triode outputs a fail-safe control signal, the base of the second triode is connected to the collector of the third triode through a ninetieth resistor, the ignition signal is connected to the base of the third triode through a series-connected second zener diode and a ninety-third resistor, and the emitter of the third triode is grounded.

2. The vehicle body controller fault control circuit according to claim 1, characterized in that, The limp home signal generation circuit includes a system basic chip SBC; the system basic chip SBC is connected to the MCU control unit and generates a limp home enable signal after detecting the failure of the MCU control unit.

3. The vehicle body controller fault control circuit according to claim 1, characterized in that, The first lighting turn-on circuit includes an intelligent MOS chip; the input end of the intelligent MOS chip is connected to the fail-safe control signal, and the output end of the intelligent MOS chip is connected to the lighting.

4. The vehicle body controller fault control circuit according to claim 3, characterized in that, The first lighting turn-on circuit further includes a first diode, and the first diode is disposed between the fail-safe control signal and the intelligent MOS chip.

5. The vehicle body controller fault control circuit according to claim 1, wherein, the first switch control load turn-on circuit includes a fourth triode and a relay driver chip; the fourth triode is respectively connected to the fail-safe control signal and the switch signal, and the fail-safe control signal and the switch signal control the working state of the fourth triode; the input end of the relay driver chip is connected to the output signal of the fourth triode, the output end of the relay driver chip is connected to the first relay, and the first relay controls the working state of the load.

6. The vehicle body controller fault control circuit according to claim 5, wherein, the first switch control load turn-on circuit further includes a second diode; the second diode is disposed between the switch signal and the fourth triode.

7. The vehicle body controller fault control circuit according to claim 5, wherein, the first switch control load turn-on circuit further includes a third diode; the third diode is disposed between the fourth triode and the relay driver chip.

8. A vehicle body control system, including an MCU control unit, wherein, it further includes the vehicle body controller fault control circuit according to any one of claims 1 to 7.

9. The vehicle body control system according to claim 8, wherein, it further includes a vehicle body controller normal control circuit; the vehicle body controller normal control circuit includes: a second lighting turn-on circuit, connected to the MCU control unit, for receiving the lighting control signal sent by the MCU control unit through an intelligent MOS chip, and controlling the lighting to turn on or off according to the lighting control signal; a second switch control load turn-on circuit, connected to the MCU control unit, for receiving the load control signal sent by the MCU control unit through a relay driver chip, driving the second relay to act according to the load control signal, and the second relay controls the working state of the connected load.

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