Reversed polarity protection circuit and wiper system including same

Abstract

A reverse polarity protection circuit and a wiper system including the same, the reverse polarity protection circuit including a MOS circuit configured to turn on a first terminal and a second terminal when a first terminal voltage of the MOS circuit is higher than a second terminal voltage, and to turn off the first terminal and the second terminal when the first terminal voltage is lower than the second terminal voltage; the anode of the first diode is connected with the first end of the MOS circuit; the anode of the second diode is connected with the first end of the triode, and the cathode of the second diode is connected with the cathode of the first diode; the second end of the triode is connected with the second end of the MOS circuit; the first resistor is connected between the cathode of the first diode and the ground; the second resistor is connected between the third end of the triode and the ground; and the third resistor is connected between the third end of the MOS circuit and the third end of the triode. The reversed polarity protection circuit can protect the power supply from being damaged by reversed polarity voltage.

Description

Technical Field

[0001] The invention relates to an electronic circuit, in particular to a reverse polarity protection circuit and a wiper system comprising the reverse polarity protection circuit. Background Art

[0002] Currently, vehicles generally include windshield wipers (also known as windshield wipers or windshield wipers, etc.) for clearing rain, snow, ice, washer fluid, water or debris from the windshield of the cab.

[0003] In response to different weather conditions or user needs, most wipers are configured to operate at different speeds, such as low speed and high speed, through a motor with multiple windings. However, when one of the multiple windings is operated, an induced voltage may be generated in other windings that are not operated. The induced voltage generated in the winding that is not operated may have an adverse effect on the power supply circuit of the wiper. Summary of the invention

[0004] The present disclosure provides a reverse polarity protection circuit, comprising: a MOS circuit, configured to turn on the first and second ends of the MOS circuit when the voltage of the first end of the MOS circuit is higher than the voltage of the second end of the MOS circuit, and to disconnect the first and second ends of the MOS circuit when the voltage of the first end of the MOS circuit is lower than the voltage of the second end of the MOS circuit; a first diode, wherein the anode of the first diode is connected to the first end of the MOS circuit; a second diode, wherein the anode of the second diode is connected to the first end of the triode, and the cathode of the second diode is connected to the cathode of the first diode; a triode, wherein the second end of the triode is connected to the second end of the MOS circuit; a first resistor, wherein the first resistor is connected between the cathode of the first diode and the ground; a second resistor, wherein the second resistor is connected between the third end of the triode and the ground; and a third resistor, wherein the third resistor is connected between the third end of the MOS circuit and the third end of the triode.

[0005] The reverse polarity protection circuit according to the present disclosure further includes: a power supply connected to the first end of the MOS circuit, and a load connected to the second end of the MOS circuit.

[0006] According to the reverse polarity protection circuit disclosed in the present invention, the MOS circuit includes a PMOS circuit, wherein the first end of the MOS circuit corresponds to the drain of the PMOS circuit, the second end of the MOS circuit corresponds to the source of the PMOS circuit, and the third end of the MOS circuit corresponds to the gate of the PMOS circuit.

[0007] According to the reverse polarity protection circuit disclosed in the present invention, the transistor includes a PNP type transistor, wherein the first end of the transistor corresponds to the base of the PNP type transistor, the second end of the transistor corresponds to the emitter of the PNP type transistor, and the third end of the transistor corresponds to the collector of the PNP type transistor.

[0008] According to the reverse polarity protection circuit disclosed in the present invention, the first resistor is at least used for current limiting and pulling down the cathode voltages of the first diode and the second diode, and the resistance value of the first resistor is between 5000 and 15000 ohms.

[0009] According to the reverse polarity protection circuit disclosed in the present invention, the second resistor is at least used for current limiting and pulling down the voltage of the third end of the MOS circuit when the voltage of the first end of the MOS circuit is higher than the voltage of the second end of the MOS circuit, and the resistance value of the second resistor is between 5000 and 15000 ohms.

[0010] According to the reverse polarity protection circuit disclosed in the present invention, the third resistor is at least used to provide a signal loop for the third end of the MOS circuit and to perform current limiting, and the resistance value of the third resistor is at least partially determined based on the current limiting requirement of the MOS circuit.

[0011] The reverse polarity protection circuit according to the present disclosure further includes a voltage regulator diode, and the voltage regulator diode is used to limit the voltage difference between the second terminal and the third terminal of the MOS circuit.

[0012] The reverse polarity protection circuit according to the present disclosure further includes an electrostatic discharge (ESD) protection circuit for protecting the reverse polarity protection circuit module and the power supply module to avoid device damage caused by an electrostatic discharge pulse.

[0013] According to the reverse polarity protection circuit of the present disclosure, the electrostatic discharge (ESD) protection circuit is configured to reduce the voltage at the second end of the MOS circuit when the voltage at the first end of the MOS circuit is lower than the voltage at the second end of the MOS circuit.

[0014] The reverse polarity protection circuit according to the present disclosure further includes a micro control unit MCU configured to monitor a voltage outputted by the reverse polarity protection circuit.

[0015] The present disclosure provides a domain controller, including the reverse polarity protection circuit according to the present disclosure as described above. For details, please refer to the description of the reverse polarity protection circuit above, which will not be repeated here for the sake of brevity.

[0016] The present disclosure provides a windshield wiper system, comprising: a windshield wiper module, the windshield wiper module comprising: a windshield wiper motor, the motor comprising at least two windings, the motor being configured to use power from a power supply module to drive a windshield wiper through the at least two windings, the windshield wiper being operably connected to one of the at least two windings; a power supply module, the power supply module being configured to supply power to the windshield wiper module; a reverse polarity protection circuit module, the reverse polarity protection circuit module comprising at least one reverse polarity protection circuit, the at least one reverse polarity protection circuit corresponding to one of the at least two windings, the at least one reverse polarity protection circuit being used to prevent a reverse polarity voltage generated by one of the at least two windings from acting on the power supply module, the at least one reverse polarity protection circuit comprising: a MOS circuit, configured to, when a voltage at a first end of the MOS circuit is higher than a voltage at a first end of the MOS circuit, The first end and the second end of the MOS circuit are turned on when the voltage at the second end of the MOS circuit is lower than the voltage at the second end of the MOS circuit, and the first end and the second end of the MOS circuit are turned off when the voltage at the first end of the MOS circuit is lower than the voltage at the second end of the MOS circuit; a first diode, wherein the anode of the first diode is connected to the first end of the MOS circuit; a second diode, wherein the anode of the second diode is connected to the first end of the triode, and the cathode of the second diode is connected to the cathode of the first diode; a triode, wherein the second end of the triode is connected to the second end of the MOS circuit; a first resistor, wherein the first resistor is connected between the cathode of the first diode and the ground; a second resistor, wherein the second resistor is connected between the third end of the triode and the ground; and a third resistor, wherein the third resistor is connected between the third end of the MOS circuit and the third end of the triode.

[0017] The present disclosure provides a motor vehicle, including the reverse polarity protection circuit according to the present disclosure and / or the wiper system according to the present disclosure as described above. For details, please refer to the description of the reverse polarity protection circuit and / or the domain controller and / or the wiper system above, which will not be repeated here for the sake of brevity.

[0018] According to the reverse polarity protection circuit and the wiper system disclosed in the present invention, when the power supply normally supplies power to the load, the power consumption generated by the reverse polarity protection circuit is extremely small. When the load sends a reverse polarity voltage to the power supply, the reverse polarity protection circuit is reversely turned off, so the power supply is protected. In addition, the reverse polarity protection circuit can be turned on and off adaptively according to the power supply voltage and the reverse polarity voltage without the need for additional control signals, thereby effectively reducing system complexity, control difficulty and manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description in conjunction with the accompanying drawings, in which:

[0020] Figure 1a It is a windshield wiper system;

[0021] Figure 1b It is another type of wiper system;

[0022] Figure 2 is a reverse polarity protection circuit according to an embodiment of the present disclosure;

[0023] Figure 3a According to the embodiment of the present disclosure Figure 2 Schematic diagram of the reverse polarity protection circuit in the forward conduction state;

[0024] Figure 3b According to the embodiment of the present disclosure Figure 2 Schematic diagram of the reverse polarity protection circuit in the reverse off-conduction state;

[0025] Figure 4 is another reverse polarity protection circuit according to an embodiment of the present disclosure;

[0026] Figure 5 is another reverse polarity protection circuit according to an embodiment of the present disclosure;

[0027] Figure 6 is another reverse polarity protection circuit according to an embodiment of the present disclosure;

[0028] Figure 7 is a windshield wiper system according to an embodiment of the present disclosure;

[0029] Figure 8 A motor vehicle according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] Before proceeding to the following detailed description, it may be advantageous to set forth definitions of certain words and phrases used throughout this disclosure. The terms "include" and "comprising" and their derivatives mean including, but not limited to. The phrase "at least one," when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one item in the list may be required. For example, "at least one of A, B, C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, A and B and C.

[0031] Definitions for other specific words and phrases are provided throughout this disclosure. Those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior and future uses of such defined words and phrases.

[0032] The various embodiments of the principles of the present disclosure in this patent document are described below in conjunction with the accompanying drawings for illustration only, and should not be interpreted as limiting the scope of the present disclosure in any way. It will be appreciated by those skilled in the art that the principles of the present disclosure can be implemented in any appropriately arranged system or device. In some cases, the actions described in the present disclosure can be performed in different orders, and still achieve the desired results. In addition, the process depicted in the accompanying drawings does not necessarily require the specific order shown or the sequential order to achieve the desired results. In a specific embodiment, multitasking and parallel processing may be advantageous.

[0033] The text and drawings are provided as examples only to help understand the present disclosure. They should not be interpreted as limiting the scope of the claims attached to the present disclosure in any way. Throughout the drawings, the same reference numerals generally indicate the same elements. Although certain embodiments and examples have been provided, based on the contents of the present disclosure, it is clear to those skilled in the art that the embodiments and examples shown may be changed without departing from the scope of the present disclosure.

[0034] Figure 1a It is a windshield wiper system.

[0035] like Figure 1a The wiper system shown can be placed in various vehicles. Vehicles include but are not limited to cars, tractors (with or without trailers), buses, recreational vehicles, minivans or sport utility vehicles (SUVs), construction equipment, agricultural equipment, aircraft, etc. As shown in FIG1 , the wiper system may include a power source 110 , a wiper motor 120 , and a wiper 130 .

[0036] The power source 110 may be configured to provide an input voltage to the wiper motor 120. The power source 110 may be a battery of the vehicle, such as a nickel-cadmium battery, a nickel-metal hydride battery, a lithium-ion battery, a polymer battery, a lead-acid battery, and the like.

[0037] The wiper motor 120 may be configured to receive an input voltage from the power source 110 and drive the wiper 130 to move in different speed modes by selecting different windings. The wiper motor 120 may include a DC motor such as a permanent magnet DC motor and an electromagnetic DC motor, and an AC motor such as a synchronous AC motor and an asynchronous AC motor. Figure 1aAs shown, the wiper motor 120 may include a first winding 121 and a second winding 122, but those skilled in the art will appreciate that the wiper motor 120 may include more windings. The first winding 121 and the second winding 122 may be used by the wiper motor 120 to drive the wiper 130 in different speed modes. In one embodiment, the first winding 121 may have more turns than the second winding 122. Therefore, the first winding 121 may correspond to a fast mode for driving the wiper 130 at a faster speed, and the second winding 122 may correspond to a slow mode for driving the wiper 130 at a slower speed. More windings with different turns may correspond to more speed modes.

[0038] The wiper 130 may include one or more of a bone wiper, a boneless wiper, and a composite wiper. The wiper 130 may be configured to be driven by the wiper motor 120 using a winding to remove rain, snow, ice, washing liquid, water, or debris on the windshield.

[0039] In one embodiment, when the user chooses to drive the wiper 130 in high-speed mode, the power supply 110 supplies power to the first winding 121 of the wiper motor 120, thereby driving the wiper 130 at high speed. However, an induced voltage may be generated in the second winding that is not powered due to electromagnetic induction with the first winding 121. The induced voltage may be opposite to the input voltage provided by the power supply 110 to the wiper motor 120. In other words, the second winding 122 that is not powered may generate a reverse polarity voltage opposite to the input voltage due to electromagnetic induction with the first winding 121 that is powered. The reverse polarity voltage may act on the power supply 110, and when the reverse polarity voltage is large enough, it may cause damage and failure of components of the power supply 110.

[0040] Figure 1b It is another type of wiper system.

[0041] Figure 1b Zhongyu Figure 1a The same parts will not be described repeatedly.

[0042] Figure 1b The wiper system in the embodiment further includes a diode 140. Due to the unidirectional conduction characteristic of the diode 140, the reverse polarity voltage induced in the winding that is not operated (e.g., the second winding) cannot be provided to the power supply 110, and the power supply 110 can therefore be protected from the reverse polarity voltage damage. However, in the case where the load of the operated winding (e.g., the first winding) is heavy, the diode 140 may generate high power consumption due to its own voltage drop and on-resistance.

[0043] Figure 2 Detailed description is given of the reverse polarity protection circuit 200 according to an embodiment of the present disclosure.

[0044] like Figure 2 The input terminal of the reverse polarity protection circuit 200 shown may be connected to the power source 110 , and the output terminal may be connected to a load, such as a winding of a wiper motor 120 .

[0045] like Figure 2 As shown, the reverse polarity protection circuit may include a MOS circuit 210 , a first diode 220 , a second diode 230 , a first resistor 240 , a second resistor 250 , a third resistor 260 , and a transistor 270 .

[0046] like Figure 2 The MOS circuit 210 may include a first terminal MOS1, a second terminal MOS2, and a third terminal MOS3. The first terminal MOS1 of the MOS circuit 210 may be connected to the anode and the input terminal of the first diode 220. The second terminal MOS2 of the MOS circuit 210 may be connected to the second terminal TR2 and the output terminal of the triode 270. The third terminal MOS3 of the MOS circuit 210 may be connected to the third resistor 260. The MOS circuit 210 is configured to turn on the first terminal MOS1 and the second terminal MOS2 when the voltage of the first terminal MOS1 is higher than the voltage of the second terminal MOS2; and to turn off the first terminal MOS1 and the second terminal MOS2 when the voltage of the first terminal MOS1 is lower than the voltage of the second terminal MOS2.

[0047] The first diode 220 and the second diode 230 may include various diodes such as a silicon diode and a germanium diode. The anode of the first diode 220 may be connected to the first terminal MOS1 of the MOS circuit 210. The cathode of the first diode 220 may be connected to the cathode of the second diode 230. The anode of the second diode 230 may be connected to the third terminal TR1 of the triode 270.

[0048] The first resistor 240 may be connected between the cathode of the first diode 220 and the ground. Figure 2 The ground shown in the figure may be a power ground. The second resistor 250 may be connected between the third terminal TR3 of the transistor 270 and the ground. The third resistor 250 may be connected between the third terminal MOS3 of the MOS circuit 210 and the third terminal TR3 of the transistor 270.

[0049] The transistor 270 may include a first terminal TR1, a second terminal TR2, and a third terminal TR3. The first terminal TR1 of the transistor 270 may be connected to the anode of the second diode 230. The second terminal TR2 of the transistor 270 may be connected to the second terminal MOS2 of the MOS circuit 210. The third terminal TR2 of the transistor 270 may be connected to one end of the second resistor 250 and one end of the third resistor 260.

[0050] In one embodiment, the MOS circuit 210 may include a PMOS circuit. For example, the first terminal MOS1 of the MOS circuit 210 corresponds to the drain of the PMOS circuit, the second terminal MOS2 of the MOS circuit 210 corresponds to the source of the PMOS circuit, and the third terminal MOS3 of the MOS circuit 210 corresponds to the gate of the PMOS circuit.

[0051] In one embodiment, the transistor 270 may include a PNP transistor. For example, the first terminal TR1 of the transistor 270 corresponds to the base of the PNP transistor, the second terminal TR2 of the transistor 270 corresponds to the emitter of the PNP transistor, and the third terminal TR3 of the transistor 270 corresponds to the collector of the PNP transistor.

[0052] Figure 3a According to the embodiment of the present disclosure Figure 2 Schematic diagram of the reverse polarity protection circuit 200 in the forward conduction state.

[0053] Just as an example, Figure 3a The first diode 220 and the second diode 230 in the circuit can be germanium diodes, and their conduction voltage drop Vdon can be equal to 0.3V. The input end can be connected to the ground via the first diode 220 and the first resistor 240. The first resistor 240 can be used to limit the current and pull down the cathode voltage of the first diode 220 and the second diode 220. The resistance of the first resistor 240 is between 5kΩ and 15kΩ. For example, the resistance of the first resistor 240 can be 10kΩ. Figure 3a As described above, when the voltage Vin provided via the input terminal is 10V, the voltage Vp1 at the point P1 = Vin - Vdon = 9.7V.

[0054] Assume that the MOS circuit 210 is turned on, and the conduction voltage drop Vmos of the MOS circuit 210 is equal to 0.1V. At this time, the voltage of the second terminal MOS2 of the MOS circuit 210 is Vin-Vmos=9.9V. Therefore, it can be determined that the voltage of the output terminal and the second terminal TR2 of the transistor 270 is 9.9V. When the voltage of the second terminal TR2 of the transistor is 9.9V, the voltage Vp1 of the point P1 as described above is Vin-Vdon=9.7V. The voltage difference between the second terminal TR2 of the transistor and the voltage Vp1 of the point P1 is 0.2V. Due to the unidirectional conduction characteristic of the second diode 230, the second diode 230 requires a conduction voltage drop of Vdon=0.3V when it is turned on. Therefore, the voltage difference between the second terminal TR2 of the transistor and the voltage Vp1 of the point P1 is not enough to turn on the second diode 230 and the transistor 270, so the transistor 270 is in the off state.

[0055] Since the transistor 270 is in the cut-off state, the third terminal TR3 of the transistor 270 cannot provide voltage for the second resistor 260 or the third resistor 270, so the third terminal MOS3 of the MOS circuit 210 can be connected to the ground via the third resistor 260 and the second resistor 250. The second resistor 250 is at least used for current limiting and pulling down the voltage of the third terminal of the MOS circuit. The resistance value of the second resistor 250 is between 5kΩ and 15kΩ, for example, the resistance value of the second resistor 250 can be 10kΩ. Therefore, the third terminal MOS3 of the MOS circuit 210 is in a low level state, and the MOS circuit 210 is turned on.

[0056] exist Figure 3a In the scenario shown, Figure 2 The reverse polarity protection circuit shown in is in a forward conduction state. The input voltage Vin provided by the power supply is provided to the output terminal as Vout after losing the smaller conduction voltage drop Vmos of the MOS circuit 210. The output terminal can be connected to a load such as a wiper motor to supply power to the winding in the wiper motor to drive the wiper action.

[0057] Figure 3b According to the embodiment of the present disclosure Figure 2 Schematic diagram of the reverse polarity protection circuit 200 in the reverse off-conduction state.

[0058] Figure 3b The figure shows a scenario where the non-operated winding in the wiper motor generates an induced voltage due to electromagnetic induction, resulting in a voltage of 12V at the output end of the reverse polarity protection circuit. Figure 3b In the example, the voltage at the input terminal Vin = 10V. Figure 3a As described, the input terminal can be connected to the ground via the first diode 220 and the first resistor 240. The first resistor 240 can be used to limit the current and pull down the cathode voltage of the first diode 220 and the second diode 220. The resistance of the first resistor 240 is between 5kΩ and 15kΩ. For example, the resistance of the first resistor 240 can be 10kΩ. Figure 3a As described above, when the voltage Vin provided via the input terminal is 10V, the voltage Vp1 at the point P1 = Vin - Vdon = 9.7V.

[0059] At this time, the voltage at the output end is Vout=12V. Therefore, it can be determined that the voltage at the second end MOS2 of the MOS circuit 210 and the second end TR2 of the transistor 270 is 12V. When the voltage at the second end TR2 of the transistor is 12V, due to the unidirectional conduction characteristic of the second diode 230, it can be determined that the voltage VTR1 at the first end TR1 of the transistor 270 is equal to the voltage at P1 plus the conduction voltage drop Vdon of the second diode 230, that is, 10V. Therefore, the voltage difference between the second end TR2 of the transistor 270 and the first end TR1 of the transistor 270 can be equal to Vout-VTR1=2V. This voltage difference is sufficient to turn on the transistor 270, so the transistor 270 is in the on state. Considering that the conduction voltage drop of the transistor 270 is 0.2V, the voltage at the third end TR3 of the transistor is 11.8V. At this time, it can be determined that the voltage at the third end MOS3 of the MOS circuit 210 is equal to the voltage 11.8V of the third end TR3 of the transistor. Therefore, the third terminal MOS3 of the MOS circuit 210 is in a high level state, so the MOS circuit 210 is turned off. The third resistor 260 can be used at least to provide a signal loop for the third terminal MOS3 of the MOS circuit 210 and to limit the current. The resistance value of the third resistor 260 can be determined at least in part based on the current limiting requirement of the MOS circuit 210.

[0060] exist Figure 3b In the scenario shown, Figure 2 The reverse polarity protection circuit shown in is in the reverse off state. The voltage Vout provided via the load terminal cannot be transmitted to the input terminal or the power supply. Therefore, the reverse polarity voltage generated by the electromagnetic induction between the unpowered winding and the powered winding cannot act on the power supply. Therefore, Figure 2 The reverse polarity protection circuit shown can protect the components of the power supply from damage and malfunction.

[0061] like Figure 2 , Figure 3a and Figure 3b According to the description, the reverse polarity protection circuit according to the embodiment of the present disclosure has at least the following advantages: when the reverse polarity protection circuit is forward-conducted, the power supply can supply power to the load, and the power consumption generated by the reverse polarity protection circuit is extremely small. When the reverse polarity protection circuit is reversely turned off, the reverse polarity protection voltage induced in the winding that is not operated cannot be transmitted to the power supply, so the power supply is protected. The reverse polarity protection circuit according to the embodiment of the present disclosure is adaptive. When connected to the wiper system, the reverse polarity protection circuit can be adaptively turned on and off according to the voltage at its input and output terminals without the need for additional control signals, thereby effectively reducing system complexity, control difficulty and manufacturing cost.

[0062] Figure 4 is another reverse polarity protection circuit 200 ′ according to an embodiment of the present disclosure.

[0063] Figure 4 Zhongyu Figure 2 Similar parts of the components of the reverse polarity protection circuit shown in will not be described repeatedly.

[0064] According to the embodiments of the present disclosure Figure 4 The reverse polarity protection circuit also includes a voltage stabilizing diode 280. The cathode of the voltage stabilizing diode 280 is connected to the second end TR2 of the transistor 270, and the anode of the voltage stabilizing diode 280 is connected to the third end TR3 of the transistor 270. In one embodiment, the voltage stabilizing diode 280 can be used to perform voltage protection on the MOS circuit 210. For example, according to the use requirements of the MOS circuit 210, the voltage difference between the second end MOS2 and the third end MOS3 of the MOS circuit 210 may not be allowed to exceed a certain threshold, otherwise the MOS circuit 210 may be damaged due to the excessively high voltage difference. The voltage stabilizing diode 280 can be selected according to the threshold. When the voltage difference between the second end MOS2 and the third end MOS3 of the MOS circuit 210 is too high to exceed the threshold, the voltage stabilizing diode 280 can stabilize the voltage difference at or below the threshold, thereby protecting the MOS circuit 210 from damage.

[0065] Figure 5 ” is another reverse polarity protection circuit 200 according to an embodiment of the present disclosure.

[0066] Figure 5 Zhongyu Figure 2 Similar parts of the components of the reverse polarity protection circuit shown in will not be described repeatedly.

[0067] According to the embodiments of the present disclosure Figure 5 The reverse polarity protection circuit also includes an electrostatic discharge (ESD) protection circuit 290. The electrostatic discharge of the external load may cause a reverse electrostatic discharge pulse to flow to the power supply, which may cause a sudden failure or potential failure of the power supply. The ESD protection circuit 290 may include one or more of a transient suppression diode TVS tube, a multilayer varistor MLV, a metal oxide varistor MOV, a polymer ESD protection device, and a glass ceramic ESD protection device. When a reverse electrostatic discharge pulse flows to the power supply due to an external load or other components, the ESD protection circuit 290 can act to discharge the electrostatic discharge pulse to protect the power supply. In one embodiment, when the unpowered winding generates a reverse polarity voltage opposite to the input voltage due to the electromagnetic induction between the powered winding, the ESD protection circuit 290 can reduce the reverse polarity voltage to a certain extent. Therefore, the ESD protection circuit 290 can also at least partially alleviate the adverse effects caused by the reverse polarity voltage.

[0068] Figure 62 is another reverse polarity protection circuit 200 ′″ according to an embodiment of the present disclosure.

[0069] Figure 6 Zhongyu Figure 2 Similar parts of the components of the reverse polarity protection circuit shown in will not be described repeatedly.

[0070] According to the embodiments of the present disclosure Figure 6 The reverse polarity protection circuit also includes a microcontroller unit (MCU) diagnostic circuit 290. Although not shown, a voltage detection component can be connected between the microcontroller unit diagnostic circuit 290 and the output terminal. The voltage detection component can be configured to detect the voltage output by the output terminal. The microcontroller unit MCU, also known as a single-chip microcomputer, is a microcomputer that integrates a central processing unit, a memory, a timer / counter, various input and output interfaces, etc. on an integrated circuit chip. The MCU diagnostic circuit 290 can monitor the voltage outputted by the reverse polarity protection circuit through the microcontroller unit MCU. When the MCU diagnostic circuit 290 monitors that the voltage outputted by the reverse polarity protection circuit is abnormal, the cause of the abnormality can be further diagnosed by itself or in other ways, for example, a power failure or a reverse polarity protection circuit failure, etc.

[0071] although Figure 4-Figure 6 The reverse polarity protection circuit is shown to include a Zener diode 280, an ESD protection circuit 290, and an MCU diagnostic circuit 295, respectively. However, as will be understood by those skilled in the art, the reverse polarity protection circuit may include one or more of the Zener diode 280, the ESD protection circuit 290, and the MCU diagnostic circuit 295 at the same time.

[0072] The domain controller or regional controller is the core of each functional domain of the car. It is mainly composed of three parts: domain master processor, operating system, and application software and algorithms. Relying on high-performance domain master processor, rich hardware interface resources and powerful software functional characteristics, the domain controller can integrate the core functions that originally require many automotive control units ECU to implement, greatly improving the system function integration, coupled with the standardized interface for data interaction, it can greatly reduce the development and manufacturing costs of this part. The reverse polarity protection circuit described in this article can be used in domain controllers or regional controllers.

[0073] Figure 7 Detailed description is given of a wiper system 700 according to an embodiment of the present disclosure.

[0074] according to Figure 7 The wiper system 700 shown may include a battery module 710 , a reverse polarity protection circuit module 720 , and a wiper module 730 .

[0075] The power module 710 may be configured to provide power to the wiper module 730. The power module 710 may include a battery of the vehicle, such as a nickel-cadmium battery, a nickel-metal hydride battery, a lithium-ion battery, a polymer battery, a lead-acid battery, and the like.

[0076] The reverse polarity protection circuits 722 and 724 included in the reverse polarity protection circuit module 720 may be configured according to Figure 2 , Figure 4-Figure 6 or a combination thereof. The reverse polarity protection circuits 722 and 724 included in the reverse polarity protection circuit module 720 may correspond to the windings 734 and 735 in the wiper module 730, respectively. The reverse polarity protection circuit in the reverse polarity protection circuit module 720 may be forward-conducted to maintain power transmission when the power module 710 supplies power to the wiper module 730 normally; and reversely turned off when the wiper module 730 sends a reverse polarity voltage to the power module 720, thereby protecting the power module 710 from damage by the reverse polarity voltage.

[0077] The wiper module 730 may include a wiper motor 732 and a wiper 733. The wiper motor 732 may be configured to drive the wiper 733 to move through the winding by the power from the power module 710. The wiper motor 732 may include a DC motor such as a permanent magnet DC motor and an electromagnetic DC motor, and an AC motor such as a synchronous AC motor and an asynchronous AC motor. Figure 7 Two windings 734, 745 are shown in the figure, but those skilled in the art will understand that the wiper motor 732 may include more windings to correspond to more wiper operation modes. In one example, more windings may each correspond to a reverse polarity protection circuit. In another example, only windings with more than a threshold number of turns may each correspond to a reverse polarity protection circuit or only the winding with the highest number of turns may correspond to a reverse polarity protection circuit.

[0078] The wiper 733 may include one or more of a bone wiper, a boneless wiper, and a composite wiper. The wiper 733 may be configured to be driven by the wiper motor 732 through the winding 734 or the winding 735, etc., to remove rain, snow, ice, washing liquid, water or debris, etc., located on the windshield.

[0079] like Figure 7 In the wiper system shown, when the power module 710 normally supplies power to the wiper module 730, the power consumption generated by the reverse polarity protection circuit module 720 is extremely small. When the wiper module 730 sends a reverse polarity voltage to the power module 710, the reverse polarity protection circuit module 720 is reversely turned off, so the power module 710 is protected. In addition, the wiper system according to the embodiment of the present disclosure can be adaptively turned on and off according to the power supply voltage and the reverse polarity voltage without the need for additional control signals, thereby effectively reducing system complexity, control difficulty and manufacturing cost.

[0080] Figure 8 A motor vehicle 800 is provided according to an embodiment of the present disclosure.

[0081] like Figure 8 As shown, the motor vehicle 800 includes the reverse polarity protection circuit 200, 200', 200", 200'" and / or the wiper system 700 according to the present disclosure as described above. For details, please refer to the description of the reverse polarity protection circuit and / or the wiper system above, which will not be repeated here for the sake of brevity.

[0082] Although the present disclosure has been described with exemplary embodiments, various changes and modifications may be suggested to one skilled in the art. The present disclosure is intended to encompass such changes and modifications as fall within the scope of the appended claims.

[0083] Any description in the present invention should not be construed as implying that any particular element, step, or function is an essential element that must be included in the claims scope. The scope of the patented subject matter is limited solely by the claims.

Claims

1. A reverse polarity protection circuit, comprising: a MOS circuit configured to conduct the first and second ends of the MOS circuit when the voltage of the first end of the MOS circuit is higher than the voltage of the second end of the MOS circuit, and to disconnect the first and second ends of the MOS circuit when the voltage of the first end of the MOS circuit is lower than the voltage of the second end of the MOS circuit; a first diode, wherein an anode of the first diode is connected to a first end of the MOS circuit; a second diode, wherein an anode of the second diode is connected to the first end of the triode, and a cathode of the second diode is connected to the cathode of the first diode; A triode, wherein a second end of the triode is connected to a second end of the MOS circuit; a first resistor, wherein the first resistor is connected between the cathode of the first diode and ground; a second resistor, wherein the second resistor is connected between the third terminal of the transistor and the ground; A third resistor, wherein the third resistor is connected between a third terminal of the MOS circuit and a third terminal of the transistor.

2. The reverse polarity protection circuit according to claim 1, further comprising: power supply, connected to the first terminal of the MOS circuit, A load is connected to the second terminal of the MOS circuit.

3. The reverse polarity protection circuit according to claim 1, wherein: The MOS circuit comprises a PMOS circuit, wherein: The first terminal of the MOS circuit corresponds to the drain of the PMOS circuit, The second end of the MOS circuit corresponds to the source of the PMOS circuit. The third terminal of the MOS circuit corresponds to the gate of the PMOS circuit.

4. The reverse polarity protection circuit according to claim 1, wherein: The transistor comprises a PNP transistor, wherein: The first end of the transistor corresponds to the base of the PNP transistor. The second end of the transistor corresponds to the emitter of the PNP transistor. The third end of the transistor corresponds to the collector of the PNP transistor.

5. The reverse polarity protection circuit according to claim 1, wherein: The first resistor is at least used for current limiting and pulling down the cathode voltages of the first diode and the second diode. The resistance of the first resistor is between 5000 and 15000 ohms.

6. The reverse polarity protection circuit according to claim 1, wherein: The second resistor is at least used for current limiting and pulling down the voltage of the third end of the MOS circuit when the voltage of the first end of the MOS circuit is higher than the voltage of the second end of the MOS circuit. The resistance of the second resistor is between 5000 and 15000 ohms.

7. The reverse polarity protection circuit according to claim 1, wherein: The third resistor is at least used to provide a signal loop for the third end of the MOS circuit and to perform current limiting. The resistance value of the third resistor is at least partially determined based on the current limiting requirement of the MOS circuit. 8 . The reverse polarity protection circuit according to claim 1 , further comprising a Zener diode, wherein the Zener diode is used to limit the voltage difference between the second terminal and the third terminal of the MOS circuit.

9. The reverse polarity protection circuit according to claim 1, further comprising an electrostatic discharge (ESD) protection circuit for protecting the reverse polarity protection circuit module and the power supply module to avoid device damage caused by an electrostatic discharge pulse.

10. The reverse polarity protection circuit according to claim 9, wherein the electrostatic discharge (ESD) protection circuit is configured to reduce a voltage at a second end of the MOS circuit when a voltage at a first end of the MOS circuit is lower than a voltage at a second end of the MOS circuit. 11 . The reverse polarity protection circuit according to claim 1 , further comprising a micro control unit (MCU) configured to monitor a voltage outputted via the reverse polarity protection circuit.

12. A domain controller comprising the reverse polarity protection circuit according to any one of claims 1 to 11.

13. A windshield wiper system, comprising: A windshield wiper module, the windshield wiper module comprising: A wiper motor, the motor comprising at least two windings, the motor being configured to use power from a power module to drive the wiper through the at least two windings, a wiper operatively connected to one of the at least two windings; a power module, wherein the power module is configured to supply power to the wiper module; A reverse polarity protection circuit module, the reverse polarity protection circuit module comprising at least one reverse polarity protection circuit, the at least one reverse polarity protection circuit corresponding to one of the at least two windings, the at least one reverse polarity protection circuit being used to prevent a reverse polarity voltage generated by one of the at least two windings from acting on a power supply module, the at least one reverse polarity protection circuit comprising: a MOS circuit configured to conduct the first and second ends of the MOS circuit when the voltage of the first end of the MOS circuit is higher than the voltage of the second end of the MOS circuit, and to disconnect the first and second ends of the MOS circuit when the voltage of the first end of the MOS circuit is lower than the voltage of the second end of the MOS circuit; A first diode, wherein an anode of the first diode is connected to a first end of the MOS circuit; a second diode, wherein an anode of the second diode is connected to a first end of the transistor, and a cathode of the second diode is connected to a cathode of the first diode; A triode, wherein a second end of the triode is connected to a second end of the MOS circuit; a first resistor, wherein the first resistor is connected between the cathode of the first diode and ground; a second resistor, wherein the second resistor is connected between the third terminal of the transistor and the ground; A third resistor, wherein the third resistor is connected between a third terminal of the MOS circuit and a third terminal of the transistor.

14. A motor vehicle comprising The reverse polarity protection circuit according to any one of claims 1 to 11; and / or The domain controller as claimed in claim 12; and / or The windshield wiper system according to claim 13.

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