High-side driver fault diagnosis system and method

Abstract

The present invention relates to a high-side driver fault diagnosis system, comprising an MCU, a driver chip, a sampling resistor, and a safety switch. The present invention also relates to a high-side driver fault diagnosis method, comprising a power-on initialization diagnosis process and a normal operation diagnosis process; wherein: the power-on initialization diagnosis process is used to check when the high-side driver is in a non-powered state; the normal operation diagnosis process is used to check when the high-side driver is in a powered-on operation state. The present invention is more accurate than the prior art; it diagnoses all circuit faults; it achieves safety protection; it determines whether the safety low side can be closed; and it realizes that all faults can be diagnosed at the right time.

Description

Technical Field

[0001] The present invention relates to the field of automotive electronic technology, and in particular to a high-side driver fault diagnosis system and method. Background Art

[0002] The main faults for high-side drivers are: high-side short circuit to ground, high-side short circuit to power supply, and open circuit.

[0003] like Figure 1 , which is a hardware logic structure diagram of a high-side driver in the prior art;

[0004] Based on the hardware structure of the prior art, the prior art fault diagnosis strategy for high-side driver is as follows: Figure 2 As shown, specifically;

[0005] In the ECU, the MCU controls the external load R through Dio_Output and outputs a high level or a low level. For fault diagnosis, the MCU collects the level of the high side through Dio_Input to diagnose faults such as short circuit to ground, short circuit to power supply, and open circuit.

[0006] A typical example is the Chinese invention patent with application number 201610015265.8 and invention name “A linkage protection and alarm circuit for BMS high-side drive”, which discloses the following technical features:

[0007] It includes a main positive circuit unit, a main negative circuit unit and a controller circuit unit; the main positive circuit unit includes a first high side switch M1, a main positive relay K1, a first gate driver Q1, a first inverter T1, a first AND gate circuit G1, a first operational amplifier N1, a first voltage divider resistor R1 and a first grounding resistor R2; the main negative circuit unit includes a second high side switch M2, a main negative relay K2, a second gate driver Q2, a second inverter T2, a second AND gate circuit G2, a second operational amplifier N2, a second voltage divider resistor R3 and a second grounding resistor R4; the controller circuit unit includes a third AND gate circuit G3 and a controller U1;

[0008] A first end of the first high side switch M1 is connected to the power supply VCC, a second end of the first high side switch M1 is connected to the anode of the first gate driver Q1, a third end of the first high side switch M1 is connected to the main positive relay K1, a control electrode GD1 of the first gate driver Q1 is connected to the output end of the second AND gate circuit G2, a cathode of the first gate driver Q1 is grounded, an input end of the first inverter T1 is connected to the second end of the first high side switch M1, an output end of the first inverter T1 is connected to the first input end of the first AND gate circuit G1, one end of the first voltage dividing resistor R1 is connected to the third end of the first high side switch M1, the other end of the first voltage dividing resistor R1 is connected to the first input end of the first operational amplifier N1, one end of the first grounding resistor R2 is connected to the first input end of the first operational amplifier N1, the other end of the first grounding resistor R2 is grounded, the second input end of the first operational amplifier N1 is connected to the output end of the first operational amplifier N1, the output end of the first operational amplifier N1 is connected to the second input end of the first AND gate circuit G1, and the output end of the first AND gate circuit G1 is connected to the control electrode GD2 of the second gate driver Q2;

[0009] A first end of the second high side switch M2 is connected to the power supply VCC, a second end of the second high side switch M2 is connected to the anode of the second gate driver Q2, a third end of the second high side switch M2 is connected to the main negative relay K2, a control electrode GD2 of the second gate driver Q2 is connected to the output end of the first AND gate circuit G1, a cathode of the second gate driver Q2 is grounded, an input end of the second inverter T2 is connected to the second end of the second high side switch M2, an output end of the second inverter T2 is connected to the first input end of the second AND gate circuit G2, one end of the second voltage dividing resistor R3 is connected to the third end of the second high side switch M2, the other end of the second voltage dividing resistor R3 is connected to the first input end of the second op amp N2, one end of the second grounding resistor R4 is connected to the first input end of the second op amp N2, the other end of the second grounding resistor R4 is grounded, the second input end of the second op amp N2 is connected to the output end of the second op amp N2, the output end of the second op amp N2 is connected to the second input end of the second AND gate circuit G2, and the output end of the second AND gate circuit G2 is connected to the control electrode GD1 of the first gate driver Q1;

[0010] The first input end of the third AND gate circuit G3 is connected to the output end of the first AND gate circuit G1, the second input end of the third AND gate circuit G3 is connected to the output end of the second AND gate circuit G2, the output end of the third AND gate circuit G3 is connected to the controller U1, and the controller U1 is respectively connected to the output end of the first AND gate circuit G1 and the output end of the second AND gate circuit G2.

[0011] The controller U1 is a single chip microcomputer.

[0012] When the main positive relay K1 and the main negative relay K2 are short-circuited at the same time, the controller U3 uses the output signal of the third AND gate circuit G3 as an alarm signal, and the controller U1 warns the user through the human-machine interface connected thereto.

[0013] When the high side drive of the main positive relay is short-circuited to the power supply, the gate drive signal of the second end of the first high side switch is pulled low, and the first high side switch is disconnected. At this time, the first voltage divider resistor and the first operational amplifier detect the short circuit to the power supply, and the first operational amplifier outputs a high level signal. The gate drive signal of the second end of the first high side switch enters the first AND gate circuit simultaneously with the high level signal output by the first operational amplifier using the first inverter. The gate drive signal of the second end of the first high side switch is pulled to a low level, indicating that the relay is to be disconnected, that is, a short circuit has occurred, and the first AND gate circuit will output a high level signal. At this time, even if the gate drive signal of the second end of the first high side switch has been pulled low, the main positive relay cannot be disconnected. The present invention uses the high level signal output by the first AND gate circuit to pull down the gate drive signal of the second end of the second high side switch of the main negative circuit unit through the second gate driver, and directly shuts down the main negative relay with a hardware circuit when the high side drive of the main positive relay is short-circuited to the power supply.

[0014] Similarly, when the high-side drive of the main negative relay is short-circuited to the power supply, the gate drive signal of the second end of the second high-side switch is pulled low, and the second high-side switch is disconnected. At this time, the second voltage-dividing resistor and the second operational amplifier detect the short circuit to the power supply, and the second operational amplifier outputs a high-level signal. The gate drive signal of the second end of the second high-side switch enters the second AND gate circuit simultaneously with the high-level signal output by the second operational amplifier using the second inverter. The gate drive signal of the second end of the second high-side switch is pulled to a low level, indicating that the relay is to be disconnected, that is, a short circuit has occurred, and the second AND gate circuit will output a high-level signal. At this time, even if the gate drive signal of the second end of the second high-side switch has been pulled low, the main negative relay cannot be disconnected. The present invention uses the high-level signal output by the second AND gate circuit to pull down the gate drive signal of the second end of the first high-side switch of the main positive circuit unit through the first gate driver, and directly shuts down the main positive relay with a hardware circuit when the high-side drive of the main negative relay is short-circuited to the power supply. That is, the main positive relay drive is turned off in the same control mode, so as to achieve the purpose of linkage control of the main positive relay and the main negative relay.

[0015] In addition, the output signals of the first AND gate circuit and the second AND gate circuit are respectively fed back to the controller of the control circuit unit, so that the controller can monitor in real time whether the high-side drivers of the main positive relay and the main negative relay are short-circuited to the power supply. In particular, when the high-side drivers of the main positive relay and the main negative relay are both short-circuited to the power supply, the third AND gate circuit will output an alarm signal representing danger to the controller, and the controller will feedback the alarm signal to the user through the human-machine interface to realize the alarm.

[0016] The defects of the prior art are:

[0017] 1. The existing technical solutions can only diagnose high-side short circuit to power supply and short circuit to ground, but cannot diagnose open circuit faults;

[0018] 2. When a fault occurs, safety protection cannot be provided; for example, when the high side is short-circuited to the power supply, the external load is always in working state. If the load is closely related to the safety of vehicle operation, it may cause unknown dangers;

[0019] 3. The judgment of fault occurrence and fault recovery need to be carried out under specific diagnostic conditions. If the diagnostic conditions are not met, the fault will be diagnosed. Summary of the invention

[0020] In view of the above problems, the present invention provides a high-side driver fault diagnosis system and method, which aims to be more accurate than the prior art; diagnose all circuit faults; achieve safety protection; determine whether the safety low side can be closed; and ensure that all faults can be diagnosed when they occur.

[0021] To solve the above problems, the technical solution provided by the present invention is:

[0022] A high-side driver fault diagnosis system includes an MCU, a driver chip, a sampling resistor, and a safety switch; wherein:

[0023] The sampling resistor is used to indirectly determine the current size in the high-side drive; the sampling resistor is connected in series in the high-side;

[0024] The safety switch is used to forcibly disconnect the safety low side;

[0025] One end of the sampling resistor is connected to the driving chip circuit, and the other end is connected to one end circuit of the safety switch;

[0026] The other end of the safety switch is grounded.

[0027] Preferably, the safety switch is electrically signal coupled to the MCU, and performs a disconnection operation or a connection operation according to a safety switch control signal from the MCU.

[0028] Preferably, the voltage at one end of the sampling resistor connected to the driving chip circuit is the point A sampling voltage; the point A sampling voltage is collected in real time and sent to the MCU;

[0029] The voltage at one end of the sampling resistor connected to the safety switch circuit is the point B sampling voltage; the point B sampling voltage is collected in real time and sent to the MCU.

[0030] Preferably, an external load is connected in series to the connection circuit between the sampling resistor and the safety switch.

[0031] Preferably, the driver chip is electrically signal coupled to the MCU and receives a driver chip input signal from the MCU;

[0032] The driving chip is also connected to a power supply voltage.

[0033] A high-side driver fault diagnosis method using a high-side driver fault diagnosis system includes a power-on initialization diagnosis process and a normal operation diagnosis process; wherein:

[0034] The power-on initialization diagnostic process is used to perform checks when the system is powered on and initialized;

[0035] The normal operation diagnosis process is used to check when the system is initialized and running periodically.

[0036] Preferably, the power-on initialization diagnosis process specifically includes the following steps:

[0037] Sa100. The MCU sends a safety switch control signal to the safety switch; the safety switch performs the disconnect operation according to the safety switch control signal from the MCU; keeps the safety low side disconnected;

[0038] Sa200. The high side driver outputs a low voltage;

[0039] Sa300. Collect the sampled voltage at point B; then send the sampled voltage at point B to the MCU; Sa400. Perform the following operations according to the value of the sampled voltage at point B:

[0040] If the value of the sampling voltage at point B is 0V, it is determined that the high side is not short-circuited to the power supply; then Sa500 is executed;

[0041] If the value of the sampled voltage at point B is equal to the value of the power supply voltage, it is determined that the high side has been short-circuited to the power supply; then Sa600 is executed;

[0042] Sa500. Return and execute Sa100 again;

[0043] Sa600. The high side driver outputs a high voltage;

[0044] Sa700 collects the sampled voltage at point B again; and then sends the sampled voltage at point B to the MCU;

[0045] Sa800. Perform the following operations according to the value of the sampling voltage at point B:

[0046] Sa900. Perform the following operations according to the value of the sampling voltage at point B:

[0047] If the value of the sampling voltage at point B is 0V, it is determined that the high side is short-circuited to the ground; then Sa1000 is executed;

[0048] If the value of the sampled voltage at point B is equal to the value of the power supply voltage, it is determined that the high side is not short-circuited to the ground; then Sa1100 is executed;

[0049] Sa1000. Return and execute Sa100 again;

[0050] Sa1100. The MCU sends a safety switch control signal to the safety switch; the safety switch performs the connection operation according to the safety switch control signal from the MCU; and keeps the safety low side closed;

[0051] Sa1200. End the execution of the power-on initialization diagnostic process.

[0052] Preferably, the normal operation diagnosis process specifically includes the following steps:

[0053] Sb100. Get the state of the safety low side;

[0054] Sb200. Perform the following operations according to the state of the safety low side:

[0055] If the state of the safety low side is closed, execute Sb300;

[0056] If the state of the safety low side is disconnected, execute Sa100;

[0057] Sb300. Get the status of high-side output;

[0058] Sb400. Perform the following operations according to the state of the high-side output:

[0059] If the state of the high-side output is outputting a low level, executing a high-side low-level diagnosis sub-process;

[0060] If the state of the high-side output is outputting a high level, the high-side high level diagnosis sub-process is executed.

[0061] Preferably, the high-side high-level diagnosis sub-process specifically includes the following steps:

[0062] Sba400 collects the sampling voltage at point A and the sampling voltage at point B; and then sends the sampling voltage at point A and the sampling voltage at point B to the MCU;

[0063] Sba410. Subtract the sampling voltage at point B from the sampling voltage at point A to obtain the voltage difference at sampling points AB;

[0064] Sba420. Compare the pressure difference between the AB sampling points with the manually preset lower limit threshold of the pressure difference between the AB sampling points; and then perform the following operations:

[0065] If the comparison result is that the pressure difference between the AB sampling points is lower than the lower limit threshold of the pressure difference between the AB sampling points, it is determined that the high side is open; then Sba450 is executed;

[0066] If the pressure difference between the AB sampling points is not lower than the lower limit threshold of the pressure difference between the AB sampling points, execute Sba430;

[0067] Sba430. Compare the pressure difference between the AB sampling points with the manually preset upper limit threshold of the pressure difference between the AB sampling points; and then perform the following operations:

[0068] If the comparison result is that the pressure difference between the AB sampling points is higher than the upper limit threshold of the pressure difference between the AB sampling points, it is determined that the high side is short-circuited to the ground; then Sba440 is executed;

[0069] If the pressure difference between the AB sampling points is not higher than the upper pressure difference threshold between the AB sampling points, it is determined that the system is operating normally; then Sba450 is executed;

[0070] Sba440 disconnects the safety low side; then executes Sba450;

[0071] Sba450. End the high-side high-level diagnosis sub-process described this time.

[0072] Preferably, the high-side low-level diagnosis sub-process specifically comprises the following steps:

[0073] Sbb400 collects the sampled voltage at point B; and then sends the sampled voltage at point B to the MCU;

[0074] Sbb410. Perform the following operations according to the value of the sampling voltage at point B:

[0075] If the value of the sampled voltage at point B is equal to the value of the power supply voltage, it is determined that the high side has been short-circuited to the power supply;

[0076] Sbb420.Execute Sba450.

[0077] Compared with the prior art, the present invention has the following advantages:

[0078] 1. The present invention uses the magnitude of the current to perform fault diagnosis, which is more accurate than the prior art;

[0079] 2. The present invention can diagnose all circuit faults;

[0080] 3. The present invention has a safety low edge, so that safety protection can be achieved;

[0081] 4. The present invention performs fault diagnosis when power is turned on to determine whether the safety low side can be closed;

[0082] 5. The present invention keeps the low side disconnected when power is turned on or a fault occurs. At this time, diagnostic conditions can be forcibly created to detect the fault, so that all faults can be diagnosed in time. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 A schematic diagram of the system hardware structure of the prior art in the background technology;

[0084] Figure 2 A schematic diagram of a diagnostic scheme flow chart of the prior art in the background technology;

[0085] Figure 3 A schematic diagram of the system structure of a specific embodiment of the present invention;

[0086] Figure 4 The figure is a flow chart of a diagnostic scheme according to a specific embodiment of the present invention.

[0087] Among them: VBAT. Power supply voltage, Output. Driver chip input signal, Adcinput_A. Point A sampling voltage, Adcinput_B. Point B sampling voltage, r. Sampling resistor, R. External load, Ctr_L. Safety switch control signal, Safeswitch. Safety switch. DETAILED DESCRIPTION

[0088] The present invention is further explained below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0089] like Figure 3 As shown, a high-side driver fault diagnosis system includes an MCU, a driver chip, a sampling resistor r, and a safety switch Safeswitch; wherein:

[0090] The sampling resistor r is used to indirectly determine the current size in the high-side driver; the sampling resistor r is connected in series in the high-side.

[0091] The safety switch Safeswitch is used to forcibly disconnect the safety low side.

[0092] In this specific embodiment, the safety switch Safeswitch is coupled to the MCU electrical signal, and performs a disconnection operation or a connection operation according to a safety switch control signal Ctr_L from the MCU.

[0093] One end of the sampling resistor r is connected to the driving chip circuit, and the other end is connected to one end circuit of the safety switch Safeswitch.

[0094] In this specific embodiment, the voltage at one end of the sampling resistor r connected to the driving chip circuit is the point A sampling voltage ADCINPUT_A; the point A sampling voltage ADCINPUT_A is collected in real time and sent to the MCU.

[0095] In this specific embodiment, the voltage at one end of the sampling resistor r connected to the safety switch Safeswitch circuit is the point B sampling voltage ADCINPUT_B; the point B sampling voltage ADCINPUT_B is collected in real time and sent to the MCU.

[0096] In this specific embodiment, an external load R is connected in series to the connection circuit between the sampling resistor r and the safety switch Safeswitch.

[0097] It should be noted that, in this specific embodiment, a sampling resistor r is added to the high side; the resistance of the sampling resistor r is much smaller than the resistance of the external load R, so as to convert the current signal passing through the external load R into a voltage signal; thus, by judging the voltage difference across the sampling resistor r, that is, the voltage difference between the AB sampling points, the current size is indirectly judged, and then combined with the size of the sampling voltage ADCINPUT_B at point B, the faults of the high side short circuit to the power supply, the high side short circuit to the ground and the open circuit are diagnosed; in this way, the defect that the prior art cannot diagnose the open circuit fault is solved.

[0098] In this specific embodiment, the other end of the safety switch Safeswitch is grounded.

[0099] It should be noted that, in this specific embodiment, the purpose of adding a safety switch Safeswitch on the low side is: when it is diagnosed that the high side is short-circuited to the power supply, the safe low side is disconnected to prevent the load from being in a working state all the time; in this way, the defect that the prior art cannot provide safety protection is solved.

[0100] It should be further explained that, when power is turned on or a fault occurs, adding a safety switch Safeswitch on the low side can keep the low side disconnected; at this time, no matter what state the high side is in, the load will not be driven, and diagnostic conditions can be forcibly created to detect faults; in this way, the defect of the prior art that a fault will be diagnosed all the time if the diagnostic conditions are not met is solved.

[0101] In this specific embodiment, the driver chip is electrically signal coupled to the MCU and receives a driver chip input signal Output from the MCU.

[0102] The driver chip is also connected to the power supply voltage VBAT.

[0103] A high-side driver fault diagnosis method using a high-side driver fault diagnosis system includes a power-on initialization diagnosis process and a normal operation diagnosis process; wherein:

[0104] The power-on initialization diagnostic process is used to check when the system is powered on and initialized.

[0105] like Figure 4 As shown, in this specific embodiment, the power-on initialization diagnosis process specifically includes the following steps:

[0106] Sa100. The MCU sends a safety switch control signal Ctr_L to the safety switch Safeswitch; the safety switch Safeswitch performs a disconnection operation according to the safety switch control signal Ctr_L from the MCU; and the safety low side is kept disconnected.

[0107] Sa200. Outputs low voltage by high-side driver.

[0108] Sa300. Collect the sampling voltage ADCINPUT_B at point B; then send the sampling voltage ADCINPUT_B at point B to the MCU.

[0109] Sa400. Perform the following operations according to the value of the sampling voltage ADCINPUT_B at point B:

[0110] If the value of the sampling voltage ADCINPUT_B at point B is 0V, it is determined that the high side is not short-circuited to the power supply; then Sa500 is executed.

[0111] If the value of the sampling voltage ADCINPUT_B at point B is equal to the value of the power supply voltage VBAT, it is determined that the high side is short-circuited to the power supply; then Sa600 is executed.

[0112] Sa500. Return and execute Sa100 again.

[0113] Sa600. Outputs high voltage through high-side driver.

[0114] Sa700. Collect the sampling voltage ADCINPUT_B at point B again; and then send the sampling voltage ADCINPUT_B at point B to the MCU.

[0115] Sa800. Perform the following operations based on the value of the sampled voltage ADCINPUT_B at point B:

[0116] Sa900. Perform the following operations based on the value of the sampling voltage ADCINPUT_B at point B:

[0117] If the value of the sampling voltage ADCINPUT_B at point B is 0V, it is determined that the high side is short-circuited to ground; then Sa1000 is executed.

[0118] If the value of the sampling voltage ADCINPUT_B at point B is equal to the value of the power supply voltage VBAT, it is determined that the high side is not short-circuited to the ground; then Sa1100 is executed.

[0119] Sa1000. Return and execute Sa100 again.

[0120] Sa1100. The MCU sends a safety switch control signal Ctr_L to the safety switch Safeswitch; the safety switch Safeswitch performs a connection operation according to the safety switch control signal Ctr_L from the MCU; and keeps the safety low side closed.

[0121] Sa1200. End the execution of this power-on initialization diagnostic process.

[0122] The normal operation diagnostic process is used to check the system after initialization is completed and it is running periodically.

[0123] In this specific embodiment, the normal operation diagnosis process specifically includes the following steps:

[0124] Sb100. Get the status of safe low side.

[0125] Sb200. Perform the following operations according to the status of the safety low side:

[0126] If the state of the safety low side is closed, execute Sb300.

[0127] If the status of the safety low side is disconnected, execute Sa100.

[0128] Sb300. Get the status of the high-side output.

[0129] Sb400. performs the following operations according to the status of the high-side output:

[0130] If the state of the high-side output is outputting a low level, the high-side low level diagnosis sub-process is executed.

[0131] In this specific embodiment, the high-side low-level diagnosis sub-process specifically includes the following steps:

[0132] Sbb400 collects the sampling voltage ADCINPUT_B at point B; and then sends the sampling voltage ADCINPUT_B at point B to the MCU.

[0133] Sbb410 performs the following operations according to the value of the sampling voltage ADCINPUT_B at point B:

[0134] If the value of the sampling voltage ADCINPUT_B at point B is equal to the value of the power supply voltage VBAT, it is determined that the high side is short-circuited to the power supply.

[0135] Sbb420.Execute Sba450.

[0136] If the state of the high-side output is outputting a high level, the high-side high-level diagnosis sub-process is executed.

[0137] In this specific embodiment, the high-side high-level diagnosis sub-process specifically includes the following steps:

[0138] Sba400 collects the sampling voltage ADCINPUT_A at point A and the sampling voltage ADCINPUT_B at point B; and then sends the sampling voltage ADCINPUT_A at point A and the sampling voltage ADCINPUT_B at point B to the MCU.

[0139] Sba410. Subtract the sampling voltage ADCINPUT_B at point B from the sampling voltage ADCINPUT_A at point A to obtain the voltage difference between the sampling points AB.

[0140] Sba420. Compare the pressure difference between the AB sampling points with the manually preset lower limit threshold of the pressure difference between the AB sampling points; then perform the following operations:

[0141] If the comparison result is that the pressure difference between the AB sampling points is lower than the lower limit threshold of the pressure difference between the AB sampling points, it is determined that the high side is open; then Sba450 is executed.

[0142] If the pressure difference between the AB sampling points is not lower than the lower limit threshold of the pressure difference between the AB sampling points, Sba430 is executed.

[0143] Sba430. Compare the pressure difference between the AB sampling points with the manually preset upper limit threshold of the pressure difference between the AB sampling points; then perform the following operations:

[0144] If the comparison result is that the voltage difference between the AB sampling points is higher than the upper voltage difference threshold between the AB sampling points, it is determined that the high side is short-circuited to the ground; then Sba440 is executed.

[0145] If the pressure difference between the AB sampling points is not higher than the upper limit threshold of the pressure difference between the AB sampling points, it is determined that the system is operating normally; then Sba450 is executed.

[0146] Sba440. Disconnect the safety low side; then execute Sba450.

[0147] Sba450. End this high-side high-level diagnosis sub-process.

[0148] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0149] The disclosed embodiments are described above to enable any person skilled in the art to implement or use the present invention. Various modifications of these embodiments are obvious to those skilled in the art, and the general principles defined herein may also be applied to other embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.

[0150] The above description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

[0151] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-side driver fault diagnosis system, characterized in that: It includes MCU, driver chip, sampling resistor (r), and safety switch (Safeswitch); among which: The sampling resistor (r) is used to indirectly determine the current size in the high-side drive; the sampling resistor (r) is connected in series in the high side; The safety switch (Safeswitch) is used to forcibly disconnect the safety low side; One end of the sampling resistor (r) is connected to the driving chip circuit, and the other end is connected to one end of the safety switch (Safeswitch) circuit; The other end of the safety switch (Safeswitch) is grounded; The safety switch (Safeswitch) is electrically signal coupled to the MCU, and performs a disconnection operation or a connection operation according to a safety switch control signal (Ctr_L) from the MCU; The voltage at one end of the sampling resistor (r) connected to the driving chip circuit is the point A sampling voltage (ADCINPUT_A); the point A sampling voltage (ADCINPUT_A) is collected in real time and sent to the MCU; The voltage at one end of the sampling resistor (r) connected to the safety switch (Safeswitch) circuit is the point B sampling voltage (ADCINPUT_B); the point B sampling voltage (ADCINPUT_B) is collected in real time and sent to the MCU; An external load (R) is connected in series to the connection circuit between the sampling resistor (r) and the safety switch (Safeswitch); The driver chip is electrically signal coupled to the MCU and receives a driver chip input signal (Output) from the MCU; The driver chip is also connected to a power supply voltage (VBAT).

2. A high-side driver fault diagnosis method using the high-side driver fault diagnosis system according to claim 1, characterized in that: It includes the power-on initialization diagnostic process and the normal operation diagnostic process; among which: The power-on initialization diagnostic process is used to perform checks when the system is powered on and initialized; The normal operation diagnostic process is used to perform checks after the system initialization is completed and periodically runs; The power-on initialization diagnostic process specifically includes the following steps: Sa100. The MCU sends a safety switch control signal (Ctr_L) to the safety switch (Safeswitch); the safety switch (Safeswitch) performs the disconnection operation according to the safety switch control signal (Ctr_L) from the MCU; and keeps the safety low side disconnected; Sa200. The high side driver outputs a low voltage; Sa300. Collect the sampling voltage (ADCINPUT_B) at point B; then send the sampling voltage (ADCINPUT_B) at point B to the MCU; Sa400. Perform the following operations according to the value of the sampling voltage (ADCINPUT_B) at point B: If the value of the sampling voltage (ADCINPUT_B) at point B is 0V, it is determined that the high side is not short-circuited to the power supply; then Sa500 is executed; If the value of the sampling voltage (ADCINPUT_B) at point B is equal to the value of the power supply voltage (VBAT), it is determined that the high side has been short-circuited to the power supply; then Sa600 is executed; Sa500. Return and execute Sa100 again; Sa600. The high side driver outputs a high voltage; Sa700. collect the sampling voltage (ADCINPUT_B) at point B again; then send the sampling voltage (ADCINPUT_B) at point B to the MCU; Sa800. Perform the following operations according to the value of the sampling voltage (ADCINPUT_B) at point B: Sa900. Perform the following operations according to the value of the sampling voltage (ADCINPUT_B) at point B: If the value of the sampling voltage (ADCINPUT_B) at point B is 0V, it is determined that the high side is short-circuited to the ground; then Sa1000 is executed; If the value of the sampling voltage (ADCINPUT_B) at point B is equal to the value of the power supply voltage (VBAT), it is determined that the high side is not short-circuited to the ground; then Sa1100 is executed; Sa1000. Return and execute Sa100 again; Sa1100. The MCU sends a safety switch control signal (Ctr_L) to the safety switch (Safeswitch); the safety switch (Safeswitch) performs the connection operation according to the safety switch control signal (Ctr_L) from the MCU; and keeps the safety low side closed; Sa1200. End the execution of the power-on initialization diagnostic process; The normal operation diagnosis process specifically includes the following steps: Sb100. Get the state of the safety low side; Sb200. Perform the following operations according to the state of the safety low side: If the state of the safety low side is closed, execute Sb300; If the state of the safety low side is disconnected, execute Sa100; Sb300. Get the status of high-side output; Sb400. Perform the following operations according to the state of the high-side output: If the state of the high-side output is outputting a low level, executing a high-side low-level diagnosis sub-process; If the state of the high-side output is outputting a high level, executing a high-side high-level diagnosis sub-process; The high-side high-level diagnosis sub-process specifically comprises the following steps: Sba400. Collect the sampling voltage (ADCINPUT_A) at point A and the sampling voltage (ADCINPUT_B) at point B; then send the sampling voltage (ADCINPUT_A) at point A and the sampling voltage (ADCINPUT_B) at point B to the MCU; Sba410. Subtract the sampling voltage at point B (ADCINPUT_B) from the sampling voltage at point A (ADCINPUT_A) to obtain the voltage difference at sampling points AB; Sba420. Compare the pressure difference between the AB sampling points with the manually preset lower limit threshold of the pressure difference between the AB sampling points; and then perform the following operations: If the comparison result is that the pressure difference between the AB sampling points is lower than the lower limit threshold of the pressure difference between the AB sampling points, it is determined that the high side is open; then Sba450 is executed; If the pressure difference between the AB sampling points is not lower than the lower limit threshold of the pressure difference between the AB sampling points, execute Sba430; Sba430. Compare the pressure difference between the AB sampling points with the manually preset upper limit threshold of the pressure difference between the AB sampling points; and then perform the following operations: If the comparison result is that the pressure difference between the AB sampling points is higher than the upper limit threshold of the pressure difference between the AB sampling points, it is determined that the high side has been short-circuited to the ground; then Sba440 is executed; If the pressure difference between the AB sampling points is not higher than the upper pressure difference threshold between the AB sampling points, it is determined that the system is operating normally; then Sba450 is executed; Sba440 disconnects the safety low side; then executes Sba450; Sba450 ends the high-side high-level diagnostic subprocess; The high-side low-level diagnosis sub-process specifically comprises the following steps: Sbb400. Collect the sampling voltage (ADCINPUT_B) at point B; then send the sampling voltage (ADCINPUT_B) at point B to the MCU; Sbb410 performs the following operations according to the value of the sampling voltage (ADCINPUT_B) at point B: If the value of the sampling voltage (ADCINPUT_B) at point B is equal to the value of the power supply voltage (VBAT), it is determined that the high side is short-circuited to the power supply; Sbb420.Execute Sba450.

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