Back emf bleed circuit, method, vehicle, medium, device, and product

Abstract

The embodiment of the application discloses a kind of counter electromotive force discharge circuit, method, vehicle, medium, equipment and product, discharge circuit includes: counter electromotive force circuit, anti-reverse circuit, drive circuit, pre-drive chip, charge pump circuit and switch tube;Counter electromotive force circuit is connected with anti-reverse circuit, drive circuit, pre-drive chip respectively, anti-reverse circuit is also connected with charge pump circuit by switch tube, drive circuit is also connected with charge pump circuit by pre-drive chip, drive circuit is also grounded;Pre-drive chip is used to control charge pump circuit to generate charge pump voltage, and monitor the voltage value of counter electromotive force generated by counter electromotive force circuit, whether control drive circuit based on the voltage value of counter electromotive force is discharged to ground;Switch tube is used to control the conduction or turn-off of anti-reverse circuit based on charge pump voltage.The embodiment of the application realizes the safe discharge of counter electromotive force.

Description

Technical Field

[0001] This application belongs to the field of vehicle body circuits, specifically relating to a back EMF discharge circuit, a back EMF discharge method, a vehicle, a storage medium, an electronic device, and a computer program product. Background Technology

[0002] During vehicle production, after the domain control module and tailgate support rod are installed, the vehicle is in a state of no power. When the tailgate is manually and quickly opened and closed, the motor inside the electric support rod will rotate and generate back electromotive force. If it is not properly discharged, it will be transmitted into the vehicle circuit and randomly interfere with other electrical modules, affecting the production plan.

[0003] Currently, conventional methods for discharging back EMF utilize drive circuits and anti-reverse circuits to guide the back EMF to the vehicle's power supply, where it is absorbed by the battery. However, this method only applies when the battery is already installed. During vehicle production, if the battery terminals are not yet installed, the back EMF can be discharged into the vehicle's electrical system, causing other electrical modules to briefly power on, triggering abnormal actions and affecting normal vehicle delivery.

[0004] Therefore, existing technologies lack a technical solution that does not rely on batteries and can safely discharge back electromotive force without interfering with the vehicle's electrical circuitry. Summary of the Invention

[0005] The purpose of this application is to provide a back EMF discharge circuit, method, vehicle, medium, device, and product that can solve the problem that existing back EMF discharge methods that rely on batteries interfere with the vehicle's circuitry.

[0006] In a first aspect, embodiments of this application provide a back electromotive force (EMF) discharge circuit, which includes: a back EMF circuit, an anti-reverse circuit, a drive circuit, a pre-drive chip, a charge pump circuit, and a switching transistor; the back EMF circuit is connected to the anti-reverse circuit, the drive circuit, and the pre-drive chip respectively; the anti-reverse circuit is also connected to the charge pump circuit through the switching transistor; the drive circuit is also connected to the charge pump circuit through the pre-drive chip; and the drive circuit is also grounded. The pre-drive chip is used to control the charge pump circuit to generate a charge pump voltage and monitor the voltage value of the back electromotive force generated by the back electromotive force circuit. Based on the voltage value of the back electromotive force, it determines whether to control the drive circuit to discharge the back electromotive force to ground. The switching transistor is used to control the conduction or shutdown of the anti-reverse circuit based on the charge pump voltage.

[0007] Optionally, the drive circuit includes a high-side power transistor, a low-side power transistor, and a motor winding; the high-side power transistor is connected to the back EMF circuit, the pre-drive chip, the low-side power transistor, and the motor winding; the low-side power transistor is also connected to the pre-drive chip, the motor winding, and ground; and the motor winding is also connected to the pre-drive chip.

[0008] Optionally, the low-side power transistor includes a first power transistor and a second power transistor; the sources of the first power transistor and the second power transistor are grounded, the drains of the first power transistor and the second power transistor are connected to the motor winding, the high-side power transistor, and the pre-drive chip, and the gates of the first power transistor and the second power transistor are connected to the pre-drive chip.

[0009] Optionally, the high-side power transistors include a third power transistor and a fourth power transistor; the sources of the third and fourth power transistors are connected to the motor windings, the low-side power transistors, and the pre-driver chip; the drains of the third and fourth power transistors are connected to the back EMF circuit; and the gates of the third and fourth power transistors are connected to the pre-driver chip.

[0010] Optionally, the pre-drive chip includes a drive channel with braking function and a power supply channel; the drive channel is connected to the drive circuit, and the power supply channel is connected to the back electromotive force circuit and the charge pump circuit.

[0011] Optionally, the pre-drive chip further includes an overvoltage monitor, the input of which is connected to the power supply channel, and the output of which is connected to the drive channel.

[0012] Optionally, the pre-driver chip includes a sleep control terminal; the switching transistor is also connected to the sleep control terminal, and the sleep control terminal is used to control the switching transistor to turn on or off.

[0013] Optionally, the anti-reverse circuit includes a fifth power transistor; the drain of the fifth power transistor is connected to the back electromotive force circuit, the gate of the fifth power transistor is connected to the switching transistor, and the source of the fifth power transistor is connected to the power supply.

[0014] Secondly, embodiments of this application provide a back EMF discharge method, applied to the back EMF discharge circuit as described in the first aspect, the method comprising: In response to the back electromotive force, the path from the charge pump voltage to the anti-reverse circuit is switched off by the switching transistor; When the voltage value of the back electromotive force exceeds a preset threshold, the braking function of the pre-drive chip is activated, and when the braking function is activated, the back electromotive force is controlled to be discharged to ground through the drive circuit.

[0015] Optionally, the step of shutting off the path of the charge pump voltage to the anti-reverse circuit via the switching transistor in response to the back electromotive force includes: In response to the back electromotive force, the pre-drive chip is controlled to generate a sleep signal; The switch is turned off based on the sleep signal to cut off the path of the charge pump voltage to the anti-reverse circuit.

[0016] Optionally, controlling the back electromotive force to be discharged to ground via the drive circuit when the braking function is activated includes: When the braking function is activated, the pre-drive chip is controlled to generate a control signal; Based on the control signal, the low-side power transistor is simultaneously turned on to discharge the back electromotive force to ground through the low-side power transistor.

[0017] Thirdly, embodiments of this application provide a vehicle including the structure of the back EMF discharge circuit as described in the first aspect, or steps for implementing the back EMF discharge method as described in the second aspect.

[0018] Fourthly, embodiments of this application provide a storage medium that stores computer instructions, which, when executed by a computer, are used to perform the steps of the back EMF discharge method as described in the second aspect.

[0019] Fifthly, embodiments of this application provide an electronic device including at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the steps of the back EMF discharge method as described in the second aspect.

[0020] In a sixth aspect, embodiments of this application provide a computer program product, including a computer program / instructions that, when executed by a processor, implement the steps of the back EMF discharge method as described in the second aspect.

[0021] In this embodiment, the switching transistor can cut off the path of the charge pump voltage to the anti-reverse circuit, thereby cutting off the path of back EMF to the vehicle circuit via the power harness. Thus, the back EMF no longer relies on the battery for absorption, solving the problem of the inability to absorb back EMF when the battery is not installed. It also avoids the risk of back EMF entering the vehicle circuit and causing abnormal operation of other electrical modules. Furthermore, based on the pre-drive chip monitoring the voltage value of the back EMF, when conditions are met, the back EMF can be controlled to be discharged to ground via the grounded drive circuit. This changes the discharge path of the back EMF from through the anti-reverse circuit to the vehicle power supply to through the drive circuit to ground, with the discharge endpoint being ground, not the vehicle power harness. This further ensures that the discharge process will not interfere with the vehicle circuit. The two paths are independent and act simultaneously, preventing back EMF interference with the vehicle and providing a safe and reliable discharge path for the back EMF. Attached Figure Description

[0022] Figure 1 This is a structural block diagram of a back EMF discharge circuit provided in an embodiment of this application; Figure 2 This is a schematic diagram of the flow of current generated by a motor in a drive circuit according to an embodiment of this application; Figure 3 This is a schematic diagram of the driving principle of a motor drive provided in an embodiment of this application; Figure 4 This is a schematic diagram illustrating the principle of changing the driving channel according to an embodiment of this application; Figure 5 This is a schematic diagram of a switching transistor provided in an embodiment of this application; Figure 6 This is a flowchart illustrating the steps of a back EMF discharge method provided in an embodiment of this application. Figure 7 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0025] The back EMF discharge circuit and back EMF discharge method provided in this application will be described in detail below with reference to the accompanying drawings and through specific embodiments and application scenarios.

[0026] Reference Figure 1 This is a structural block diagram of a back EMF discharge circuit provided in an embodiment of this application, specifically including: a back EMF circuit 1, an anti-reverse circuit 2, a drive circuit 3, a pre-drive chip 4, a charge pump circuit 5, and a switching transistor 6; the back EMF circuit 1 is connected to the anti-reverse circuit 2, the drive circuit 3, and the pre-drive chip 4 respectively; the anti-reverse circuit 2 is also connected to the charge pump circuit 5 through the switching transistor 6; the drive circuit 3 is also connected to the charge pump circuit 5 through the pre-drive chip 4; and the drive circuit 3 is also grounded. The pre-drive chip 4 is used to control the charge pump circuit 5 to generate a charge pump voltage and monitor the voltage value of the back electromotive force generated by the back electromotive force circuit 1. Based on the voltage value of the back electromotive force, it determines whether to control the drive circuit 3 to discharge the back electromotive force to ground. The switching transistor 6 is used to control the conduction or cutoff of the anti-reverse circuit 2 based on the charge pump voltage.

[0027] In this embodiment, the back EMF circuit 1 is the power supply bus of the electric strut drive circuit, used to generate a back EMF when the electric strut is dragged by an external force, and transmit the back EMF to the anti-reverse circuit 2, the drive circuit 3, and the pre-drive chip 4. The anti-reverse circuit 2 is connected between the back EMF circuit 1 and the vehicle power supply 7, used to connect the back EMF circuit 1 and the vehicle power supply 7 when it is turned on. The drive circuit 3 is connected between the back EMF circuit 1 and ground, used to connect the back EMF circuit 1 and ground under the control of the pre-drive chip 4, so that the back EMF can be discharged to ground through this path. The charge pump circuit 5 is used to generate a charge pump voltage under the control of the pre-drive chip 4, which provides the control voltage required for the anti-reverse circuit 2 to be turned on. The switching transistor 6 is connected between the charge pump circuit 5 and the anti-reverse circuit 2, used to control whether the charge pump voltage can be transmitted to the anti-reverse circuit 2. The pre-drive chip 4 is the control core of the back EMF discharge circuit. It is used to control the charge pump circuit 5 to generate the charge pump voltage and to monitor the voltage value of the back EMF on the back EMF circuit 1 in real time.

[0028] Specifically, the back EMF circuit 1 is connected to the anti-reverse circuit 2, which provides a discharge path for the back EMF to the vehicle power supply 7 via the anti-reverse circuit 2; the back EMF circuit 1 is connected to the drive circuit 3, which provides a discharge path for the back EMF to ground via the drive circuit 3; the back EMF circuit 1 is connected to the pre-drive chip 4, which enables the pre-drive chip 4 to directly acquire the voltage signal on the back EMF circuit 1 so as to monitor the voltage value of the back EMF in real time.

[0029] The anti-reverse circuit 2 is connected to the charge pump circuit 5 via a switching transistor 6. This connection provides a path for the charge pump voltage to be transmitted to the control terminal of the anti-reverse circuit 2. The switching transistor 6 acts as the control switch for this path, determining whether the charge pump voltage can reach the control terminal of the anti-reverse circuit 2. The drive circuit 3 is connected to the charge pump circuit 5 via a pre-driver chip 4. This connection enables the pre-driver chip 4 to generate a control signal using the charge pump voltage to control the drive circuit 3 to perform corresponding on or off actions. The drive circuit 3 is grounded, providing a physical path for the back electromotive force to be discharged to ground through the drive circuit 3.

[0030] In practical applications, there are two scenarios: one with and one without back EMF. In the scenario without back EMF, where the electric strut is not dragged by an external force and no back EMF is generated in the back EMF circuit 1, the pre-drive chip 4 controls the charge pump circuit 5 to operate normally, generating a charge pump voltage. This charge pump voltage is transmitted to the control terminal of the anti-reverse circuit 2 via the switching transistor 6, keeping the anti-reverse circuit 2 in a conducting state. At this time, the vehicle power supply 7 supplies power to the back EMF circuit 1 normally via the anti-reverse circuit 2, and the drive circuit 3 drives the electric strut motor to operate normally under the control of the pre-drive chip 4. In this state, the switching transistor 6 remains conducting, ensuring a smooth path for the charge pump voltage to the anti-reverse circuit 2.

[0031] In scenarios involving back electromotive force (EMF), specifically when the electric strut is dragged by an external force and generates back EMF, the back EMF is transmitted via back EMF circuit 1 to anti-reverse circuit 2, drive circuit 3, and pre-drive chip 4. At this time, the back EMF acts simultaneously on two possible discharge paths: one path through anti-reverse circuit 2 to the vehicle power supply 7, and the other path through drive circuit 3 to ground. To prevent the back EMF from discharging through anti-reverse circuit 2 to the vehicle power supply 7 and interfering with other electrical modules, pre-drive chip 4 uses switching transistor 6 to cut off the path from charge pump circuit 5 to anti-reverse circuit 2. This causes the control terminal of anti-reverse circuit 2 to lose charge pump voltage, thus keeping anti-reverse circuit 2 off. The path of back EMF through anti-reverse circuit 2 to the vehicle power supply 7 is cut off, eliminating the risk of back EMF entering the vehicle circuitry. Furthermore, to further determine whether to control the drive circuit, pre-drive chip 4 also monitors the voltage value on back EMF circuit 1 in real time and compares this value with a preset threshold. If the back electromotive force (EMF) voltage does not exceed the preset threshold, the pre-driver chip 4 does not trigger active discharge, and the back EMF is naturally dissipated and absorbed through the impedance path of other components connected to the back EMF circuit 1. If the back EMF voltage exceeds the preset threshold, the pre-driver chip 4 determines that active discharge needs to be performed. The pre-driver chip 4 controls the drive circuit 3 through its braking function, so that the back EMF circuit 1 is connected to ground. At this time, the back EMF can be discharged to ground through the drive circuit 3, realizing the safe discharge of the back EMF.

[0032] In this embodiment, the switching transistor 6 can cut off the path from the charge pump voltage to the anti-reverse circuit 2, thereby cutting off the path of back EMF to the vehicle circuit via the power harness. Thus, the back EMF no longer relies on the battery for absorption, solving the problem of the battery not being able to absorb the back EMF. It also avoids the risk of back EMF entering the vehicle circuit and causing abnormal operation of other electrical modules. Furthermore, based on the pre-drive chip 4 monitoring the voltage value of the back EMF, it can control the back EMF to be discharged to ground via the grounded drive circuit 3 when conditions are met. This changes the discharge path of the back EMF from through the anti-reverse circuit 2 to the vehicle power supply 7 to through the drive circuit 3 to ground, with the discharge endpoint being ground, not the vehicle power supply 7 harness. This further ensures that the discharge process will not interfere with the vehicle circuit. The two paths are independent and act simultaneously, preventing back EMF interference with the vehicle and providing a safe and reliable discharge path for the back EMF.

[0033] In one embodiment of this application, the drive circuit 3 includes a high-side power transistor 31, a low-side power transistor 32, and a motor winding 33; the high-side power transistor 31 is connected to the back EMF circuit 1, the pre-drive chip 4, the low-side power transistor 32, and the motor winding 33; the low-side power transistor 32 is also connected to the pre-drive chip 4, the motor winding 33, and ground; and the motor winding 33 is also connected to the pre-drive chip 4.

[0034] Reference Figure 2This is a schematic diagram illustrating the flow of current generated by a motor in a drive circuit, provided in an embodiment of this application. Figure 2 (a) indicates that the motor is rotating forward. Figure 2 (b) represents motor reversal, showing three current flow directions. Specifically, ① is the current flow direction in drive circuit 3 when the motor is operating normally in both forward and reverse directions; ② is the current flow direction in drive circuit 3 when the tailgate is manually opened and closed in the brake state; ③ is the current flow direction in drive circuit 3 when the current is freewheeling through the freewheeling diode (body diode) in the coast state (high resistance state).

[0035] In this embodiment, the driving circuit 3 is an H-bridge topology circuit, such as... Figure 2 As shown, the drive circuit 3 consists of three parts: a high-side power transistor 31, a low-side power transistor 32, and a motor winding 33.

[0036] The high-side power transistor 31 refers to the MOS (Metal-Oxide-Semiconductor) transistor connected between the back EMF circuit 1 and the motor winding 33. Its drain is connected to the back EMF circuit 1 to receive power from the bus, its source is connected to one end of the motor winding 33 to provide drive current to the motor, and its gate is connected to the pre-driver chip 4 to receive control signals. The low-side power transistor 32 refers to the MOS transistor connected between the motor winding 33 and ground. Its drain is connected to the corresponding end of the motor winding 33, its source is grounded to form a current loop, and its gate is connected to the pre-driver chip 4 to receive control signals.

[0037] The two ends of the motor winding 33 are respectively connected to the connection nodes of the high-side power transistor 31 and the low-side power transistor 32. Specifically, one end of the motor winding 33 is connected to the node between the source of the high-side power transistor 31 and the drain of the low-side power transistor 32, and the other end of the motor winding 33 is connected to the node between the source of another high-side power transistor 31 and the drain of another low-side power transistor 32. The voltage at the two winding ends is controlled by the switching states of the corresponding high-side power transistor 31 and low-side power transistor 32. The pre-driver chip 4 controls the switching of the energizing direction of the motor winding 33 by controlling the on and off combinations of the high-side power transistor 31 and the low-side power transistor 32, thereby controlling the motor to rotate forward or backward.

[0038] This embodiment of the application constructs a complete H-bridge power stage using high-side power transistor 31, low-side power transistor 32, and motor winding 33, providing a hardware foundation for the forward and reverse drive control of the motor and the discharge control of back EMF. Under the control of the pre-driver chip 4, high-side power transistor 31 and low-side power transistor 32 coordinate their operation, realizing both the bidirectional drive function of the motor and providing a switchable discharge path for the back EMF.

[0039] In one embodiment of this application, the low-side power transistor 32 includes a first power transistor 321 and a second power transistor 322; the sources of the first power transistor 321 and the second power transistor 322 are grounded, the drains of the first power transistor 321 and the second power transistor 322 are connected to the motor winding 33, the high-side power transistor 31, and the pre-drive chip 4, and the gates of the first power transistor 321 and the second power transistor 322 are connected to the pre-drive chip 4.

[0040] Reference Figure 3 This is a schematic diagram of the driving principle of a motor drive provided in an embodiment of this application, showing the connection relationship between the back EMF circuit 1, the drive circuit 3, and the pre-drive chip 4.

[0041] In this embodiment, the low-side power transistor 32 includes a first power transistor 321 and a second power transistor 322, corresponding to the low-side switches of the left and right half-bridges of the H-bridge, respectively. Figure 3 As shown, the source of the first power transistor 321 and the source of the second power transistor 322 are both grounded, providing a physical path to ground for back EMF discharge; the drain of the first power transistor 321 is connected to one end of the motor winding 33 and the corresponding high-side power transistor 31, and the drain of the second power transistor 322 is connected to the other end of the motor winding 33 and the corresponding high-side power transistor 31, forming the midpoint of the left and right half-bridge arms, and the motor winding 33 is connected across these two midpoints; the gate of the first power transistor 321 and the gate of the second power transistor 322 are respectively connected to the corresponding drive channel 41 of the pre-driver chip 4 to receive the control signal output by the pre-driver chip 4.

[0042] The drains of the first power transistor 321 and the second power transistor 322 are also connected to the pre-driver chip 4. That is, the connection node between the first power transistor 321, the second power transistor 322 and the high-side power transistor 31 also needs to be connected to the pre-driver chip 4.

[0043] In one embodiment of this application, the high-side power transistor 31 includes a third power transistor 311 and a fourth power transistor 312; the sources of the third power transistor 311 and the fourth power transistor 312 are connected to the motor winding 33, the low-side power transistor 32, and the pre-drive chip 4; the drains of the third power transistor 311 and the fourth power transistor 312 are connected to the back electromotive force circuit 1; and the gates of the third power transistor 311 and the fourth power transistor 312 are connected to the pre-drive chip 4.

[0044] In this embodiment, the high-side power transistor 31 includes a third power transistor 311 and a fourth power transistor 312, corresponding to the high-side switches of the left and right half-bridges of the H-bridge, respectively. Figure 3As shown, the drains of both the third power transistor 311 and the fourth power transistor 312 are connected to the back EMF circuit 1 to obtain the bus power required for motor drive. The source of the third power transistor 311 is connected to one end of the motor winding 33 and the corresponding low-side power transistor 32 (the drain of the first power transistor 321), forming the midpoint of the left half-bridge arm; the source of the fourth power transistor 312 is connected to the other end of the motor winding 33 and the corresponding low-side power transistor 32 (the drain of the second power transistor 322), forming the midpoint of the right half-bridge arm. The motor winding 33 is connected across the source of the third power transistor 311 and the source of the fourth power transistor 312. The gates of the third power transistor 311 and the fourth power transistor 312 are respectively connected to the pre-driver chip 4 to receive the control signals output by the pre-driver chip 4.

[0045] The source of the third power transistor 311 and the source of the fourth power transistor 312 are also connected to the pre-driver chip 4. That is, the connection node between the third power transistor 311, the fourth power transistor 312 and the low-side power transistor 32 also needs to be connected to the pre-driver chip 4.

[0046] Specifically, under normal driving conditions, the pre-drive chip 4 controls the alternating conduction of the third power transistor 311 and the fourth power transistor 312 with the first power transistor 321 and the second power transistor 322, causing the current to flow through the motor winding 33 in different directions, thereby achieving forward and reverse rotation control of the motor. For example, when the third power transistor 311 and the second power transistor 322 are simultaneously turned on, the current flows from the back EMF circuit 1 through the third power transistor 311 into the motor winding 33, and then through the second power transistor 322 to ground, causing the motor to rotate forward; when the fourth power transistor 312 and the first power transistor 321 are simultaneously turned on, the current flows through the motor winding 33 in the reverse direction, causing the motor to rotate in reverse.

[0047] In the back EMF discharge scenario, the gates of the third power transistor 311 and the fourth power transistor 312 have no control signal and are in the off state. However, the body diodes of the third power transistor 311 and the fourth power transistor 312 form a signal channel for the back EMF to be transmitted from the motor winding 33 side to the pre-driver chip 4, enabling the overvoltage monitor inside the pre-driver chip 4 to obtain the voltage value of the back EMF. When the pre-driver chip 4 determines that the voltage value exceeds the preset threshold, it simultaneously outputs a high-level control signal to the gates of the first power transistor 321 and the second power transistor 322 through its braking function, causing the first power transistor 321 and the second power transistor 322 to conduct simultaneously. Since the sources of the first power transistor 321 and the second power transistor 322 are both grounded, their conduction channels provide a low-resistance path from both ends of the motor winding 33 to ground. The back EMF current flows from the motor winding 33 through the conduction channels of the first power transistor 321 and the second power transistor 322 to ground, realizing the safe discharge of the back EMF to ground. When the voltage value does not exceed the preset threshold, the pre-drive chip 4 does not trigger the active discharge action, and the back EMF is naturally consumed and absorbed through the impedance path of other components connected on the back EMF circuit 1.

[0048] In simple terms, the first power transistor 321 and the second power transistor 322 act as discharge actuators when the braking function is activated, providing a current path from the back EMF to ground; the body diodes of the third power transistor 311 and the fourth power transistor 312 serve as voltage monitoring channels, providing a back EMF voltage signal to the pre-driver chip 4, enabling the pre-driver chip 4 to detect the back EMF voltage value in real time, and triggering the low-side power transistor to conduct when it is determined to exceed a preset threshold. Figure 3 As shown, the direction of back EMF flow in the back EMF discharge scenario is ④→⑤→⑥.

[0049] In this embodiment, the coordinated operation of the four power transistors enables the back electromotive force to be effectively reduced during the discharge process, thereby preventing overvoltage damage and ensuring the safe release of back electromotive force energy without interfering with external circuits.

[0050] In one embodiment of this application, the pre-drive chip 4 includes a drive channel 41 with braking function and a power supply channel 42; the drive channel 41 is connected to the drive circuit 3, and the power supply channel 42 is connected to the back electromotive force circuit 1 and the charge pump circuit 5.

[0051] Reference Figure 4 This is a schematic diagram of the principle of changing the driving channel provided in the embodiment of this application, showing the connection relationship between the pre-drive chip 4 and the back EMF circuit 1, charge pump circuit 5, driving circuit 3, and switching transistor 6.

[0052] like Figure 4As shown, the pre-drive chip 4 includes a drive channel 41 with braking function and a primary drive channel 43 without braking function. In the prior art, the drive of the strut is usually controlled through the primary drive channel 43 without braking function. Since the primary drive channel 43 does not have braking function, when back electromotive force is generated, the pre-drive chip 4 cannot actively control the low-side power transistor 32 in the drive circuit 3 to conduct simultaneously through the primary drive channel 43. Therefore, the back electromotive force can only be discharged to the vehicle power supply 7 through the anti-reverse circuit 2, relying on the battery for absorption, and cannot be safely discharged when the battery is not installed. In order to actively control the drive circuit 3 to discharge when back electromotive force is generated, this embodiment switches the drive of the strut from the primary drive channel 43 to the drive channel 41 with braking function, and connects the gate of the first power transistor 321 and the gate of the second power transistor 322 in the drive circuit 3 through the drive channel 41. When the voltage value of the back electromotive force exceeds the preset threshold, the pre-drive chip 4 outputs a control signal to the gate of the first power transistor 321 and the gate of the second power transistor 322 through the drive channel 41 with braking function, so that the first power transistor 321 and the second power transistor 322 are turned on at the same time, short-circuiting the two ends of the motor winding 33, thereby providing a discharge path for the back electromotive force to ground through the drive circuit 3, and realizing the safe discharge of the back electromotive force.

[0053] Specifically, the output terminal of the pre-drive chip 4 serves as the control terminal of the drive circuit 3. To facilitate the description of the connection relationship between the drive channel 41 and the drive circuit 3, it is uniformly defined that the drive channel 41 of the pre-drive chip 4 is connected to the drive circuit 3 through the connection terminal 8. Among them, the drive channel 41 with braking function is connected to the gate of the first power transistor 321 and the second power transistor 322.

[0054] like Figure 4 As shown, the pre-driver chip 4 also has a power supply channel 42, which includes a PVDD channel and a VCP channel. Specifically, the back EMF circuit 1 is connected to the PVDD channel, which allows the voltage signal on the back EMF circuit 1 to be directly transmitted to the PVDD channel, enabling real-time monitoring of the back EMF voltage value. The charge pump circuit 5 is connected to the VCP channel, which allows the charge pump voltage generated by the charge pump circuit 5 to be input to the pre-driver chip 4 via the VCP channel, serving as the power supply for the pre-driver chip 4 and providing the gate control voltage required to drive the first power transistor 321, the second power transistor 322, the third power transistor 311, and the fourth power transistor 312 to the drive channel 41.

[0055] In this embodiment, the drive of the strut is switched from the original drive channel 43 without braking function to the drive channel 41 with braking function. This allows the pre-drive chip 4 to actively control the low-side power transistor 32 to conduct simultaneously when a back electromotive force (EMF) is generated and the voltage value exceeds a preset threshold, safely discharging the back EMF to ground and avoiding interference with the vehicle power supply 7. Simultaneously, real-time monitoring of the back EMF voltage is achieved through the connection of the PVDD channel to the back EMF circuit 1, and the pre-drive chip 4 can obtain the power supply required for drive through the VCP channel to the charge pump circuit 5, ensuring that the drive channel 41 can output sufficient gate control level, enabling the pre-drive chip 4 to coordinate and control the entire process of back EMF discharge.

[0056] In one embodiment of this application, the pre-drive chip 4 further includes an overvoltage monitor, the input terminal of which is connected to the power supply channel 42, and the output terminal of which is connected to the drive channel 41.

[0057] In this embodiment, the pre-drive chip 4 also includes an overvoltage monitor. Specifically, the PVDD channel is connected to the input terminal of the overvoltage monitor, that is, the voltage value of the back electromotive force received by the PVDD channel is used as the input of the overvoltage monitor. The output terminal of the overvoltage monitor is connected to the drive channel 41. When the overvoltage monitor determines that the voltage value on the PVDD channel exceeds a preset threshold, its output terminal outputs a braking activation signal to the drive channel 41 to activate the braking function of the pre-drive chip 4, that is, to trigger the drive channel 41 to perform the braking function, and at the same time outputs control signals to the gates of the first power transistor 321 and the second power transistor 322.

[0058] It should be noted that as long as the pre-drive chip 4 receives a back electromotive force, the overvoltage monitor needs to remain in working condition to continuously monitor the voltage on the PVDD channel and ensure that the braking function can be triggered in a timely manner.

[0059] In this embodiment, the voltage value on the PVDD channel is monitored in real time by an overvoltage monitor. When the voltage value of the back electromotive force exceeds a preset threshold, the drive channel 41 is automatically triggered to perform the braking function. No external controller intervention is required. The response speed is fast and the reliability is high, ensuring that the back electromotive force can be discharged in time.

[0060] In one embodiment of this application, the pre-driver chip 4 includes a sleep control terminal 44; the switch 6 is also connected to the sleep control terminal 44, and the sleep control terminal 44 is used to control the switching of the switch 6 to be turned on or off.

[0061] like Figure 4 As shown, the pre-driver chip 4 also includes a sleep control terminal 44, which is connected to the switching transistor 6 via the control terminal 9 to control the switching transistor 6 to turn on or off.

[0062] Reference Figure 5 This is a schematic diagram of a switching transistor provided in an embodiment of this application, showing the connection relationship between the anti-reverse circuit 2 and the charge pump circuit 5 through the switching transistor 6.

[0063] In the prior art, when a back electromotive force (EMF) is generated, the anti-reverse circuit 2 directly responds to the back EMF and conducts without any control. Therefore, the back EMF will inevitably be discharged to the vehicle power supply 7 through the anti-reverse circuit 2. Since the conduction of the anti-reverse circuit 2 depends only on the presence of the charge pump voltage, which is triggered by the back EMF itself, the back EMF causes the anti-reverse circuit 2 to conduct, and the conducted anti-reverse circuit 2 then leads the back EMF to the vehicle power supply 7. There is no link in the process that can actively cut off this discharge path. Therefore, this discharge path is forcibly conducted when the back EMF is generated and cannot be cut off according to actual needs. At the same time, in the prior art, the sleep control terminal 44 of the pre-drive chip 4 is only used to control the chip's own sleep and wake-up, and there is no control relationship between it and the anti-reverse circuit 2. During the chip's sleep period, the anti-reverse circuit 2 can still respond to the back EMF and conduct freely, resulting in the back EMF still being discharged to the vehicle power supply 7 through the anti-reverse circuit 2 even when the vehicle is not powered on or in standby mode. Therefore, when the battery is not installed, the back electromotive force will be directly connected to the vehicle's circuitry, causing interference to the vehicle's control module and other electrical modules.

[0064] To address the aforementioned issues, this embodiment of the application provides a switch 6 positioned between the charge pump circuit 5 and the reverse protection circuit 2. The switch 6 is controlled by a sleep control terminal 44, making it a controllable element in the conduction path of the reverse protection circuit 2. When a back electromotive force (EMF) is generated, the sleep control terminal 44 generates a sleep signal in response to the back EMF signal or an external control command, controlling the switch 6 to turn off. This cuts off the transmission path of the charge pump voltage to the reverse protection circuit 2, keeping the reverse protection circuit 2 off and preventing back EMF from entering the vehicle's electrical system. When the back EMF disappears or the vehicle requires normal power supply, the sleep control terminal 44 exits the sleep state, controlling the switch 6 to turn on, restoring the transmission path of the charge pump voltage to the reverse protection circuit 2, allowing the reverse protection circuit 2 to conduct normally. In this way, the hibernation control terminal 44 dynamically controls the conduction and cutoff of the switch tube 6 according to the presence or absence of back EMF or the change of the vehicle's working state, fundamentally solving the problem of uncontrollable back EMF discharge path in the prior art. It can effectively prevent back EMF from interfering with the vehicle's circuit when the battery is not installed or the vehicle is in hibernation state.

[0065] Specifically, the sleep control terminal 44 is used to control the pre-drive chip 4 to enter or exit sleep mode. When the pre-drive chip 4 receives a sleep command, the sleep control terminal 44 outputs a sleep signal. On the one hand, this causes the internal circuit of the pre-drive chip 4 to enter a low-power sleep mode. On the other hand, the sleep signal is transmitted to the control terminal of the switching transistor 6, controlling the switching transistor 6 to turn off, cutting off the path from the charge pump circuit 5 to the anti-reverse circuit 2, causing the control terminal of the anti-reverse circuit 2 to lose the charge pump voltage, and the anti-reverse circuit 2 remains off. When the pre-drive chip 4 receives a wake-up command, the sleep control terminal 44 outputs a wake-up signal (e.g., a high-level signal), controlling the switching transistor 6 to turn on, restoring the path from the charge pump circuit 5 to the anti-reverse circuit 2, allowing the anti-reverse circuit 2 to conduct normally. Thus, during the sleep period of the pre-drive chip 4, the switching transistor 6 is also in the off state. Even if a back electromotive force is generated, the anti-reverse circuit 2 cannot conduct, and the back electromotive force cannot be discharged to the vehicle power supply 7 through the anti-reverse circuit 2, ensuring that the vehicle circuit is not affected by back electromotive force in the sleep state.

[0066] Meanwhile, the sleep control terminal 44 can also control the pre-drive chip 4 to maintain the braking function ready state during sleep. When the pre-drive chip 4 is in sleep mode, its internal overvoltage monitor remains operational, continuously monitoring the voltage on the back EMF circuit 1. If the back EMF voltage exceeds a preset threshold during sleep, the overvoltage monitor directly triggers the braking function of the pre-drive chip 4, causing the pre-drive chip 4 to output a conduction control signal to the gate of the low-side power transistors (first power transistor 321 and second power transistor 322) in the drive circuit 3 through the drive channel with braking function, controlling the first power transistor 321 and the second power transistor 322 to conduct simultaneously, discharging the back EMF to ground through the drive circuit 3. Since the anti-reverse circuit 2 has been cut off by the switch 6 at this time, the back EMF can only be discharged to ground through the drive circuit 3, and will not interfere with the vehicle circuit. Thus, even in the dormant state, the pre-drive chip 4 can still actively perform a discharge action in response to a back EMF exceeding a preset threshold. At the same time, the anti-reverse circuit 2 remains off to ensure that the back EMF will not be fed into the vehicle power supply 7, thereby achieving safe discharge of back EMF and protection of the vehicle circuit in the dormant state.

[0067] In the sleep state, if the voltage value of the back electromotive force does not exceed the preset threshold, the pre-drive chip 4 will not trigger the braking function, and the back electromotive force will be naturally consumed and absorbed by other components connected to the back electromotive force circuit 1.

[0068] It should be noted that the reverse polarity protection circuit 2 is the only path connecting to the vehicle power supply 7 when back electromotive force (EMF) is generated. If it is conducting, the back EMF will directly enter the wiring harness of the vehicle power supply 7 through this path, causing interference to other electrical modules. After the reverse polarity protection circuit 2 is turned off, this path is physically cut off, and the back EMF cannot flow from the back EMF circuit 1 to the vehicle power supply 7 through the reverse polarity protection circuit 2, fundamentally eliminating the risk of back EMF interference to the vehicle circuit. At the same time, after the reverse polarity protection circuit 2 is turned off, the energy of the back EMF is confined to the back EMF circuit 1 and its connected drive circuit 3. It can only be discharged to ground through the drive circuit 3 controlled by the pre-drive chip 4, or consumed and absorbed by other components on the back EMF circuit 1, and will not affect the external circuit.

[0069] In this embodiment, the sleep control terminal 44 simultaneously controls the sleep state of the pre-driver chip 4 and the on / off state of the switching transistor 6. During the chip sleep period, the anti-reverse circuit 2 is kept off, which further enhances the safety and reliability of the circuit in the standby state. At the same time, the switch transistor 6 being turned off in the sleep state also avoids unnecessary path leakage of the charge pump voltage during the sleep period, reducing standby power consumption.

[0070] In one embodiment of this application, the anti-reverse circuit 2 includes a fifth power transistor 21; the drain of the fifth power transistor 21 is connected to the back electromotive force circuit 1, the gate of the fifth power transistor 21 is connected to the switching transistor 6, and the source of the fifth power transistor 21 is connected to the power supply.

[0071] like Figure 5 As shown, the anti-reverse circuit 2 includes a fifth power transistor 21, wherein the drain of the fifth power transistor 21 is connected to the back EMF circuit 1, the gate of the fifth power transistor 21 is connected to the switching transistor 6, and the source of the fifth power transistor 21 is connected to the vehicle power supply 7.

[0072] Specifically, the fifth power transistor 21 is a MOSFET, and its gate voltage is supplied by the charge pump voltage provided by the charge pump circuit 5 via the switching transistor 6. When the switching transistor 6 is turned on, the charge pump voltage is transmitted to the gate of the fifth power transistor 21, giving the gate of the fifth power transistor 21 a control level higher than its source voltage. The fifth power transistor 21 is turned on, and at this time, the back EMF circuit 1 is connected to the vehicle power supply 7 through the conduction channel of the fifth power transistor 21. The back EMF can be discharged to the vehicle power supply 7 through this path. When the switching transistor 6 is turned off, the charge pump voltage cannot be transmitted to the gate of the fifth power transistor 21, and the gate of the fifth power transistor 21 loses its control level and is at a low potential. The fifth power transistor 21 is turned off, and the path between the back EMF circuit 1 and the vehicle power supply 7 is cut off. The back EMF cannot be discharged to the vehicle power supply 7 through this path. Therefore, by controlling the gate voltage of the fifth power transistor 21, the switching transistor 6 controls the conduction and cutoff of the anti-reverse circuit 2. That is, when the switching transistor 6 is on, the fifth power transistor 21 is on, and when the switching transistor 6 is off, the fifth power transistor 21 is off.

[0073] This embodiment of the application achieves active control of the conduction state of the anti-reverse circuit 2 by controlling the gate voltage of the fifth power transistor 21 through the switching transistor 6. When a back electromotive force (EMF) is generated and the voltage value is high, requiring active discharge, the switching transistor 6 is turned off, keeping the fifth power transistor 21 off and cutting off the path of the back EMF to the vehicle power supply 7, ensuring that the back EMF does not interfere with the vehicle circuit. When no back EMF is generated or the voltage value is low and no active intervention is required, the switching transistor 6 is turned on, keeping the fifth power transistor 21 on, ensuring that the vehicle power supply 7 supplies normal power to the back EMF circuit 1. This embodiment of the application achieves flexible control of the conduction and shutdown of the anti-reverse circuit 2, enabling it to switch its operating mode according to the actual state of the back EMF, without affecting normal power supply, and effectively preventing the back EMF from interfering with the vehicle circuit.

[0074] Reference Figure 6 This is a flowchart illustrating the steps of a back electromotive force discharge method provided in an embodiment of this application, specifically including the following steps: Step 601: In response to the back electromotive force, the path from the charge pump voltage to the anti-reverse circuit 2 is turned off by the switch 6; Step 601: When the voltage value of the back electromotive force exceeds a preset threshold, activate the braking function of the pre-drive chip 4, and control the back electromotive force to be discharged to ground through the drive circuit 3 when the braking function is activated.

[0075] In this embodiment, the back EMF discharge method is applied to the back EMF discharge circuit of the aforementioned embodiment. When a back EMF is generated, the path from the charge pump voltage to the anti-reverse circuit 2 is cut off by the switch 6, keeping the anti-reverse circuit 2 off. This cuts off the path from the source of the back EMF to the vehicle power supply 7 via the anti-reverse circuit 2, preventing the back EMF from interfering with other electrical modules by entering the vehicle circuit. At this time, the turn-off of the switch 6 does not depend on the voltage value of the back EMF. That is, regardless of the voltage value of the back EMF, as long as the back EMF is detected, the cut-off operation is performed, thereby ensuring that the path from the anti-reverse circuit 2 to the vehicle power supply 7 is physically disconnected under any back EMF generation.

[0076] Subsequently, the pre-drive chip 4 monitors the voltage value of the back electromotive force in real time and compares it with a preset threshold. Based on the comparison result, it decides whether to activate the braking function. If the voltage value of the back electromotive force exceeds the preset threshold, it means that the energy of the back electromotive force is high and needs to be actively discharged to ground. The pre-drive chip 4 activates its braking function and outputs a control signal to the low-side power transistor 32 in the drive circuit 3 through the drive channel 41, controlling the low-side power transistor 32 to conduct simultaneously, so that the back electromotive force is discharged to ground through the drive circuit 3.

[0077] When the back EMF voltage value does not exceed the preset threshold, it means that the back EMF voltage value is low and its energy is small, which is not enough to cause substantial interference to the vehicle circuit. Therefore, there is no need to perform active discharge. Its energy can be consumed by the natural impedance of components such as the internal resistance of the motor winding 33 and the line impedance. At this time, the pre-drive chip 4 does not need to activate the braking function. The back EMF is consumed and absorbed by other components connected on the back EMF circuit 1.

[0078] In one embodiment of this application, the step of shutting off the path of the charge pump voltage to the anti-reverse circuit 2 via the switch 6 in response to the back electromotive force includes: In response to the back electromotive force, the pre-drive chip 4 is controlled to generate a sleep signal; The switch 6 is turned off based on the sleep signal, thereby cutting off the path of the charge pump voltage to the anti-reverse circuit 2.

[0079] like Figure 4 and Figure 5 As shown, the sleep control terminal 44 of the pre-driver chip 4 is connected to the control terminal of the switching transistor 6, and is used to control the switching transistor 6 to turn on and off. When a back electromotive force is generated, the pre-driver chip 4 responds to the back electromotive force by generating a sleep signal through its sleep control terminal 44. This sleep signal causes the pre-driver chip 4 to enter a low-power sleep state and is also transmitted to the control terminal of the switching transistor 6 to control the switching transistor 6 to turn off. After the switching transistor 6 is turned off, the path from the charge pump circuit 5 to the anti-reverse circuit 2 is cut off, the charge pump voltage cannot reach the control terminal of the anti-reverse circuit 2, and the anti-reverse circuit 2 remains off.

[0080] In one embodiment of this application, controlling the back electromotive force to be discharged to ground via the drive circuit 3 when the braking function is activated includes: When the braking function is activated, the pre-drive chip 4 is controlled to generate a control signal; Based on the control signal, the low-side power transistor 32 is simultaneously turned on to discharge the back electromotive force to ground through the low-side power transistor 32.

[0081] like Figure 3As shown, the pre-drive chip 4 has a braking function drive channel 41 connected to the gates of the first power transistor 321 and the second power transistor 322 in the drive circuit 3. When the pre-drive chip 4 determines that the back electromotive force voltage exceeds a preset threshold, it generates a control signal through the braking function drive channel 41 and outputs it to the gates of the first power transistor 321 and the second power transistor 322 respectively. After receiving the control signal, the first power transistor 321 and the second power transistor 322 are simultaneously turned on. Since the sources of the first power transistor 321 and the second power transistor 322 are both grounded, their simultaneous conduction forms a low-resistance path from both ends of the motor winding 33 to ground. The back electromotive force is discharged to ground through the conduction channel of the first power transistor 321 and the second power transistor 322, realizing the safe discharge of the back electromotive force. The simultaneous conduction of the first power transistor 321 and the second power transistor 322 also realizes the short circuit between the two ends of the motor winding 33, putting the motor in an electrical braking state, further suppressing the rotation tendency of the motor and accelerating the decay process of the back electromotive force energy.

[0082] It should be noted that, for the sake of simplicity, the method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of this application are not limited to the described order of actions, because according to the embodiments of this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of this application.

[0083] This application also provides a vehicle that includes the structure of the back EMF discharge circuit described above, or steps for implementing the back EMF discharge method described above.

[0084] This application also provides a storage medium that stores computer instructions. When the computer executes the computer instructions, it is used to perform the various processes of the above-described back EMF discharge method embodiments and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0085] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0086] This application also provides an electronic device, including a processor 7010, a memory 709, and a program or instructions stored in the memory 709 and executable on the processor 7010. When the program or instructions are executed by the processor 7010, they implement the various processes of the above-described back EMF discharge method embodiments and achieve the same technical effects. To avoid repetition, they will not be described again here.

[0087] It should be noted that the electronic devices in the embodiments of this application include the mobile electronic devices and non-mobile electronic devices described above.

[0088] Figure 7 A schematic diagram of the hardware structure of an electronic device to implement an embodiment of this application.

[0089] The electronic device 700 includes, but is not limited to, components such as: radio frequency unit 701, network module 702, audio output unit 703, input unit 704, sensor 705, display unit 706, user input unit 707, interface unit 708, memory 709, and processor 7010.

[0090] Those skilled in the art will understand that the electronic device 700 may also include a power supply (such as a battery) for supplying power to various components. The power supply may be logically connected to the processor 7010 through a power management system, thereby enabling functions such as managing charging, discharging, and power consumption through the power management system. Figure 7 The electronic device structure shown does not constitute a limitation on the electronic device. The electronic device may include more or fewer components than shown, or combine certain components, or have different component arrangements, which will not be elaborated here.

[0091] This application also provides a computer program product, including a computer program / instruction. When the computer program / instruction is executed by a processor, it implements the various processes of the above-described back EMF discharge method embodiment and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0092] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0093] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0094] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A back electromotive force discharge circuit, characterized in that, include: The circuit includes a back electromotive force circuit, an anti-reverse circuit, a drive circuit, a pre-drive chip, a charge pump circuit, and a switching transistor. The back electromotive force circuit is connected to the anti-reverse circuit, the drive circuit, and the pre-drive chip. The anti-reverse circuit is also connected to the charge pump circuit through the switching transistor. The drive circuit is also connected to the charge pump circuit through the pre-drive chip. The drive circuit is also grounded. The pre-drive chip is used to control the charge pump circuit to generate a charge pump voltage and monitor the voltage value of the back electromotive force generated by the back electromotive force circuit. Based on the voltage value of the back electromotive force, it determines whether to control the drive circuit to discharge the back electromotive force to ground. The switching transistor is used to control the conduction or shutdown of the anti-reverse circuit based on the charge pump voltage.

2. The discharge circuit according to claim 1, characterized in that, The drive circuit includes a high-side power transistor, a low-side power transistor, and a motor winding. The high-side power transistor is connected to the back EMF circuit, the pre-drive chip, the low-side power transistor, and the motor winding. The low-side power transistor is also connected to the pre-drive chip, the motor winding, and ground. The motor winding is also connected to the pre-drive chip.

3. The discharge circuit according to claim 2, characterized in that, The low-side power transistor includes a first power transistor and a second power transistor; the sources of the first power transistor and the second power transistor are grounded, the drains of the first power transistor and the second power transistor are connected to the motor winding, the high-side power transistor, and the pre-drive chip, and the gates of the first power transistor and the second power transistor are connected to the pre-drive chip.

4. The discharge circuit according to claim 2, characterized in that, The high-side power transistors include a third power transistor and a fourth power transistor; the sources of the third and fourth power transistors are connected to the motor windings, the low-side power transistors, and the pre-driver chip; the drains of the third and fourth power transistors are connected to the back EMF circuit; and the gates of the third and fourth power transistors are connected to the pre-driver chip.

5. The discharge circuit according to claim 1, characterized in that, The pre-drive chip includes a drive channel with braking function and a power supply channel; the drive channel is connected to the drive circuit, and the power supply channel is connected to the back electromotive force circuit and the charge pump circuit.

6. The discharge circuit according to claim 5, characterized in that, The pre-drive chip also includes an overvoltage monitor, the input of which is connected to the power supply channel, and the output of which is connected to the drive channel.

7. The discharge circuit according to claim 1, characterized in that, The pre-driver chip includes a sleep control terminal; the switching transistor is also connected to the sleep control terminal, which is used to control the switching transistor to turn on or off.

8. The discharge circuit according to claim 1, characterized in that, The anti-reverse circuit includes a fifth power transistor; the drain of the fifth power transistor is connected to the back electromotive force circuit, the gate of the fifth power transistor is connected to the switching transistor, and the source of the fifth power transistor is connected to the power supply.

9. A method for discharging back electromotive force, characterized in that, An application to a back EMF discharge circuit according to any one of claims 1-7, comprising: In response to the back electromotive force, the path from the charge pump voltage to the anti-reverse circuit is switched off by the switching transistor; When the voltage value of the back electromotive force exceeds a preset threshold, the braking function of the pre-drive chip is activated, and when the braking function is activated, the back electromotive force is controlled to be discharged to ground through the drive circuit.

10. The venting method according to claim 9, characterized in that, The step of switching off the path of the charge pump voltage to the anti-reverse circuit via the switching transistor in response to the back electromotive force includes: In response to the back electromotive force, the pre-drive chip is controlled to generate a sleep signal; The switch is turned off based on the sleep signal to cut off the path of the charge pump voltage to the anti-reverse circuit.

11. The venting method according to claim 9, characterized in that, The step of controlling the back electromotive force to be discharged to ground via the drive circuit when the braking function is activated includes: When the braking function is activated, the pre-drive chip is controlled to generate a control signal; Based on the control signal, the low-side power transistor is simultaneously turned on to discharge the back electromotive force to ground through the low-side power transistor.

12. A vehicle, characterized in that, Includes the back EMF discharge circuit as described in any one of claims 1-8, or is used to implement a back EMF discharge method as described in any one of claims 9-11.

13. A storage medium, characterized in that, The storage medium stores computer instructions, which, when executed by the computer, are used to perform a back electromotive force discharge method as described in any one of claims 9-11.

14. An electronic device, characterized in that, Includes at least one processor; and, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, which, when executed by the at least one processor, enables the at least one processor to perform a back EMF discharge method as described in any one of claims 9-11.

15. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instruction is executed by the processor, it implements a back EMF discharge method as described in any one of claims 9-11.

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