Overvoltage protection circuit and method, and height sensor and vehicle

Abstract

Provided in the present application are an overvoltage protection circuit and method, and a height sensor and a vehicle. The overvoltage protection circuit comprises a field-effect transistor switch, a triode switch, a first resistor, a second resistor, a third resistor, and a fourth resistor, wherein when no short circuit occurs, a source electrode of the field-effect transistor switch outputs a target signal that is the same as an output signal; and when a short circuit occurs, the triode switch is in a turned-on state, and the field-effect transistor switch is in a turned-off state. In this way, the overvoltage protection circuit can ensure normal transmission of an output signal of an integrated chip in the case of there being no short circuit, and can prevent, in the case of a short circuit and by means of turning off a field-effect transistor switch, a relatively high short-circuit voltage from reaching an output pin of the integrated chip; therefore, the overvoltage protection for the integrated chip is realized, and the risk of damage to a height sensor in the case of a short circuit, etc., is avoided.

Description

Overvoltage protection circuit, method, height sensor and vehicle

[0001] This application claims priority to Chinese Patent Application No. 202411217448.9, filed on August 30, 2024, entitled “Overvoltage Protection Circuit, Method, Altitude Sensor and Vehicle”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of vehicle manufacturing technology, and in particular to an overvoltage protection circuit, method, height sensor, and vehicle. Background Technology

[0003] With the continuous development of vehicle manufacturing technology, the application of height sensors is becoming increasingly widespread. Height sensors can measure the height of a vehicle's center of gravity, thereby ensuring the vehicle's power performance and stability. Height sensors are mainly based on the Hall effect sensing principle (HALL), and can specifically include integrated circuit chips (HALL-IC) based on the Hall effect sensing principle.

[0004] Altitude sensors used in vehicles typically need to meet certain anti-interference requirements, such as not being damaged by a short circuit in the power supply line. However, in related technologies, the output voltage signal pins of altitude sensors used in vehicles usually have low voltage withstand capability, posing a certain risk of damage in situations such as a short circuit in the power supply line. Summary of the Invention

[0005] This application provides an overvoltage protection circuit, method, height sensor, and vehicle that can achieve short-circuit protection without affecting normal signal transmission, thereby reducing the risk of damage to the height sensor under short-circuit conditions.

[0006] In a first aspect, embodiments of this application provide an overvoltage protection circuit, which is applied to a height sensor. The overvoltage protection circuit includes: a field-effect transistor switch, a transistor switch, a first resistor, a second resistor, a third resistor, and a fourth resistor.

[0007] The drain of the field-effect transistor switch is used to receive the output signal of the integrated chip; the source of the field-effect transistor switch is connected to one end of the first resistor, and the other end of the first resistor is connected to the gate of the field-effect transistor switch; the gate of the field-effect transistor switch and the other end of the first resistor are respectively connected to one end of the second resistor, and the other end of the second resistor is grounded.

[0008] The collector of the transistor switch is connected to the source of the field-effect transistor switch; the emitter of the transistor switch is connected to one end of the second resistor; the base of the transistor switch is connected to one end of the third resistor and one end of the fourth resistor, respectively; the other end of the third resistor is connected to the source of the field-effect transistor switch; and the other end of the fourth resistor is connected to one end of the second resistor.

[0009] In the absence of a short circuit, the source output of the field-effect transistor switch is the same as the output signal; in the presence of a short circuit, the transistor switch is in the ON state and the field-effect transistor switch is in the OFF state.

[0010] In one possible implementation, when no short circuit occurs and the output signal is high, the field-effect transistor switch is in the ON state, and the target signal output from the source of the field-effect transistor switch is in the high-level state.

[0011] When no short circuit occurs and the output signal is low, the field-effect transistor switch is in the off state, and the target signal output from the source of the field-effect transistor switch is in the low-level state.

[0012] In one possible implementation, in the event of a short circuit, the transistor switch enters the on state, making the gate-source voltage difference of the field-effect transistor switch zero, and the field-effect transistor switch enters the off state.

[0013] In one possible implementation, the overvoltage protection circuit further includes a capacitor; the source of the field-effect transistor switch is connected to one end of the capacitor, and the other end of the capacitor is connected to one end of the second resistor.

[0014] In one possible implementation, the overvoltage protection circuit further includes a Zener diode; the source of the MOSFET switch is connected to the negative terminal of the Zener diode, and the positive terminal of the Zener diode is connected to one end of the second resistor.

[0015] In one possible implementation, the field-effect transistor switch is a P-channel metal-oxide-semiconductor field-effect transistor; the transistor switch is an NPN transistor.

[0016] In one possible implementation, the first resistor is used to form a voltage difference between the source and gate of the field-effect transistor switch; the second resistor is a grounding resistor.

[0017] In one possible implementation, the third resistor is used to limit the base current of the transistor switch; the fourth resistor is used to form a voltage difference between the base and emitter of the transistor switch.

[0018] In a second aspect, embodiments of this application provide an overvoltage protection method, which is applied to the overvoltage protection circuit described in any one of the first aspects, comprising:

[0019] In the absence of a short circuit, the system receives the output signal from the integrated chip and outputs a target signal that is identical to the output signal.

[0020] In the event of a short circuit, the control MOSFET switch is turned off, so that the output pin of the integrated chip is isolated from the short circuit voltage.

[0021] Thirdly, embodiments of this application provide a height sensor, the height sensor including the overvoltage protection circuit described in any of the first aspects.

[0022] Fourthly, embodiments of this application provide a vehicle, the vehicle including a height sensor, the height sensor including the overvoltage protection circuit described in any of the first aspects.

[0023] Fifthly, embodiments of this application provide a storage medium storing a computer program thereon, which, when executed by a processor, implements the overvoltage protection method described in the second aspect.

[0024] In a sixth aspect, embodiments of this application provide a chip, the chip including a memory and a processor, the memory storing code and data, the memory being coupled to the processor, and the processor running a program in the memory causing the chip to perform the overvoltage protection method described in the second aspect above.

[0025] In a seventh aspect, embodiments of this application provide a program product, including: a computer program, which, when the program product is run on a computer, causes the computer to execute the overvoltage protection method described in the second aspect.

[0026] Eighthly, embodiments of this application provide a computer program that, when executed by a processor, performs the overvoltage protection method described in the second aspect above.

[0027] The overvoltage protection circuit, method, altitude sensor, and vehicle provided in this application embodiment are described below. The overvoltage protection circuit, applied to the altitude sensor, specifically includes a field-effect transistor (FET) switch, a transistor switch, a first resistor, a second resistor, a third resistor, and a fourth resistor. The drain of the FET switch receives the output signal from the integrated chip. The source of the FET switch is connected to one end of the first resistor, and the other end of the first resistor is connected to the gate of the FET switch. The gate of the FET switch and the other end of the first resistor are respectively connected to one end of the second resistor, and the other end of the second resistor is grounded. The collector of the transistor switch is connected to the source of the FET switch. The emitter of the transistor switch is connected to one end of the second resistor. The base of the transistor switch is connected to one end of the third resistor and one end of the fourth resistor, respectively. The other end of the third resistor is connected to the source of the FET switch, and the other end of the fourth resistor is connected to one end of the second resistor. In the absence of a short circuit, the source of the FET switch outputs a target signal identical to the output signal. In the event of a short circuit, the transistor switch is in a conducting state, and the FET switch is in a disconnected state. In this way, the overvoltage protection circuit can ensure the normal transmission of the integrated chip's output signal when there is no short circuit, and can prevent the high short-circuit voltage from reaching the integrated chip's output pin by disconnecting the field-effect transistor switch when there is a short circuit. This can achieve overvoltage protection for the integrated chip and avoid damage to the height sensor in the event of a short circuit or other similar situations. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 is a schematic diagram of an overvoltage protection circuit provided in an embodiment of this application;

[0030] Figure 2 is a schematic diagram of another overvoltage protection circuit provided in an embodiment of this application;

[0031] Figure 3 is a schematic diagram of the architecture of a height sensor system in related technologies;

[0032] Figure 4 is a schematic diagram of the circuit structure of a height sensor in the related technology;

[0033] Figure 5 is a schematic diagram of the system architecture of a height sensor provided in an embodiment of this application;

[0034] Figure 6 is a schematic flowchart of an overvoltage protection method provided in an embodiment of this application. Detailed Implementation

[0035] To enable those skilled in the art to better understand the technical solutions of this application, the application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments and drawings described herein are merely for explaining this application and are not intended to limit this application. It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of related data must comply with relevant laws, regulations and standards, and corresponding operation entry points are provided for users to choose to authorize or refuse.

[0036] In a vehicle's Electronic-Controlled Air Suspension (ECAS) system, the height sensor is a crucial component. The height sensor measures the vehicle's center of gravity height, thereby ensuring the vehicle's dynamic performance and stability. The active height sensor design circuit typically consists of an integrated chip coupled with auxiliary filtering circuitry. The core electronic component of this active height sensor is the IC, which performs functions such as input / output voltage conversion, sensing the measured physical quantity, signal conditioning, microcontroller signal calculation and storage, and signal output.

[0037] Because integrated chips typically employ the Hall effect sensing principle to achieve height sensing, these chips are also known as Hall effect integrated circuits (HALL-ICs). Specifically, a HALL-IC converts a height signal into a deflection angle signal via a connecting rod to a rotating shaft. A permanent magnet is fixed at the top of the shaft; as the shaft rotates, the static magnetic field generated by the permanent magnet rotates accordingly. The HALL-IC generates a small voltage signal in response to this magnetic field change. This signal is then amplified and processed by internal signal conditioning circuitry, ultimately outputting the required voltage signal. Therefore, the height sensor first converts the height signal into a magnetic deflection angle signal using a mechanical structure, and then the HALL-IC converts this magnetic deflection angle signal into an electrical signal. The integrity, reliability, and stability of the height sensor's electrical function primarily depend on the HALL-IC.

[0038] Typically, automotive active height sensors need to meet certain interference immunity requirements, such as those set by the International Organization for Standardization (ISO).

[0039] The interference immunity requirements specified in 16750-2 4.10 stipulate that the sensor must not be damaged when its output signal is short-circuited to the power supply line. Specifically, in the vehicle manufacturing field, such as in the commercial vehicle sector, the power supply is typically a 24-volt (V) system. When the vehicle battery directly powers the sensor, the height sensor must not be damaged when its output signal line is short-circuited to 32V (the upper limit of the normal operating voltage of the 24V system).

[0040] Since the reliability and anti-interference performance of the electrical functions of active height sensors mainly depend on the HALL-IC body, in related technologies, the output voltage signal pins of HALL-IC in the vehicle manufacturing field have insufficient voltage withstand capability, which does not meet the design requirements of direct power supply from vehicle batteries. In the event of a short circuit in the power line, the height sensor is at risk of damage.

[0041] To address the aforementioned issues, this application provides an overvoltage protection circuit for a height sensor employing a HALL-IC. This overvoltage protection circuit includes a field-effect transistor (FET) switch, a transistor switch, a first resistor, a second resistor, a third resistor, and a fourth resistor. The drain of the FET switch receives the output signal from the integrated chip. The source of the FET switch is connected to one end of the first resistor, and the other end of the first resistor is connected to the gate of the FET switch. The gate of the FET switch and the other end of the first resistor are respectively connected to one end of the second resistor, and the other end of the second resistor is grounded. The collector of the transistor switch is connected to the source of the FET switch. The emitter of the transistor switch is connected to one end of the second resistor. The base of the transistor switch is connected to one end of the third resistor and one end of the fourth resistor, respectively. The other end of the third resistor is connected to the source of the FET switch, and the other end of the fourth resistor is connected to one end of the second resistor. In the absence of a short circuit, the source of the FET switch outputs a target signal identical to the output signal. In the event of a short circuit, the transistor switch is in a conducting state, and the FET switch is in a de-energized state. In this way, the overvoltage protection circuit can ensure the normal transmission of the integrated chip's output signal when there is no short circuit, and can prevent the high short-circuit voltage from reaching the integrated chip's output pin by disconnecting the field-effect transistor switch when there is a short circuit. This can achieve overvoltage protection for the integrated chip and avoid the risk of damage to the height sensor in the event of a short circuit.

[0042] The following detailed description of the solution presented in this application is provided through specific embodiments. It should be noted that the following embodiments may exist independently or in combination with each other; identical or similar content will not be repeated in different embodiments.

[0043] Figure 1 is a schematic diagram of an overvoltage protection circuit provided in an embodiment of this application. As shown in Figure 1, the overvoltage protection circuit is applied to a height sensor. The overvoltage protection circuit includes: a field-effect transistor switch Q1, a transistor switch Q2, a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4. Among them, the field-effect transistor switch Q1 includes three electrodes: a drain (6), a source (5), and a gate (1), while the transistor switch Q2 includes three electrodes: a collector (2), an emitter (3), and a base (4).

[0044] The drain (6) of the field-effect transistor switch Q1 is used to receive the output signal of the integrated circuit IC (specifically, the Hall sensor integrated circuit IC, etc.); the source (5) of the field-effect transistor switch Q1 is connected to one end of the first resistor R1, and the other end of the first resistor R1 is connected to the gate (1) of the field-effect transistor switch Q1; the gate (1) of the field-effect transistor switch Q1 and the other end of the first resistor R1 are respectively connected to one end of the second resistor R2, and the other end of the second resistor R2 is grounded.

[0045] The collector (2) of transistor switch Q2 is connected to the source (5) of field-effect transistor switch Q1; the emitter (3) of transistor switch Q2 is connected to one end of the second resistor R2; the base (4) of transistor switch Q2 is connected to one end of the third resistor R3 and one end of the fourth resistor R4 respectively, the other end of the third resistor is connected to the source (5) of field-effect transistor switch Q1, and the other end of the fourth resistor R4 is connected to one end of the second resistor R2.

[0046] In the absence of a short circuit, the source (5) of the field-effect transistor switch Q1 outputs the same target signal as the output signal; in the presence of a short circuit, the transistor switch Q2 is in the on state and the field-effect transistor switch Q1 is in the off state.

[0047] Specifically, in the overvoltage protection circuit, the field-effect transistor switch Q1 can be a switch including a field-effect transistor (FET). This FET can specifically refer to a junction FET (JFET) or a metal-oxide-semiconductor FET (MOSFET). This application embodiment does not limit the specific type of the FET. The transistor switch Q2 can be an NPN transistor; this application embodiment also does not limit the specific type of transistor.

[0048] In the absence of a short circuit, the field-effect transistor switch Q1 in the overvoltage protection circuit can output the same target signal as the integrated chip's output signal, ensuring that the high and low levels of the target signal and the output signal remain consistent and guaranteeing accurate signal transmission. In the event of a short circuit, the transistor switch Q2 in the overvoltage protection circuit is in the ON state, while the field-effect transistor switch Q1 is in the OFF state, thus providing overvoltage protection for the integrated chip IC. In this way, the overvoltage protection circuit transmits electrical signals normally when the circuit connection is normal, without affecting the original integrated chip output signal. When the height sensor output line and power line are short-circuited, the overvoltage protection circuit will cause the field-effect transistor switch Q1 to be in the OFF state, preventing the high short-circuit voltage from reaching the integrated chip's output pin, thereby protecting the integrated chip's output pin under overvoltage conditions.

[0049] In one possible implementation, when no short circuit occurs and the output signal is high, the field-effect transistor switch Q1 is in the on state, and the target signal output from the source (5) of the field-effect transistor switch Q1 is in the high-level state; when no short circuit occurs and the output signal is low, the field-effect transistor switch Q1 is in the off state, and the target signal output from the source (5) of the field-effect transistor switch Q1 is in the low-level state.

[0050] Specifically, the output signal in the integrated circuit IC is a normal pulse square wave, and its level may be different at different times, as shown in Figure 1, which shows the pulse square waves of the output signal at different times from t0 to t4. When the line connection is normal, there is no short circuit, and the pulse square wave of the output signal of the IC signal output pin is in a high level (High, H) state, the drain (6) of the field-effect transistor switch Q1 is in the H state. The current flows through the body diode of the field-effect transistor switch Q1 to the source (5). The voltage difference between the source (5) pin and the drain (6) pin is one PN junction (i.e., body diode). At this time, the voltage of the gate (1) of the field-effect transistor switch Q1 is lower than that of the source (5), generating a voltage Vgs between the source (5) and the gate (1). This voltage Vgs drives the field-effect transistor switch Q1 to be in the on state. After that, the current can flow from the drain (6) of the field-effect transistor switch Q1 through the gate (1) to the source (5). In this way, the voltage of the source (5) pin and the drain (6) pin of the field-effect transistor switch Q1 are kept consistent, and the voltage of the drain (6) pin can be output, which can eliminate the PN junction voltage difference generated before. At this time, the sensor output pin is also in the H state, realizing the normal transmission of the output signal and ensuring the consistency between the target signal and the output signal.

[0051] When the circuit connection is normal, no short circuit occurs, and the pulse square wave of the output signal of the IC signal output pin is in a low level (Low, L) state, the drain (6) pin of the field-effect transistor switch Q1 is in the L state. At this time, the voltage difference (Vgs) between the gate (1) and source (5) of the field-effect transistor switch Q1 is 0, and the field-effect transistor switch Q1 is in the open state. Since the source (5) of the field-effect transistor switch Q1 is connected to ground (GND) through the first resistor R1 and the second resistor R2, the target signal output by the height sensor is also in the L state, realizing the normal transmission of the output signal. In this way, by adding an overvoltage protection circuit at the output end of the integrated chip IC, the output line can work normally when there is no fault such as connection short circuit, ensuring the accurate transmission of the output signal. The design is simple, and there is no need to change the interface circuit, and the cost is also low.

[0052] In one possible implementation, in the event of a short circuit, transistor switch Q2 enters the on state, making the voltage difference between the gate (1) and source (5) of field-effect transistor switch Q1 zero, and the field-effect transistor switch enters the off state.

[0053] Specifically, when a short circuit occurs between the height sensor output line and the power supply line, a positive voltage exists between the collector (2) and emitter (3), and a positive voltage also exists between the base (4) and emitter (3). At this time, the positive voltage is greater than a specific value (e.g., 0.7V), and the current in the base (4) causes the current in the collector (2) to reach a saturation value. At this time, the transistor switch Q2 is turned on. The turn-on of the transistor switch Q2 makes the voltage difference Vgs between the gate (1) and source (5) of the field-effect transistor switch Q1 zero, and the field-effect transistor switch Q1 is in the off state. In this way, the high short-circuit voltage at the source (5) pin of the field-effect transistor switch Q1 caused by the short circuit cannot be transmitted to the drain (6) of the field-effect transistor switch Q1, which can protect the IC output pin from high voltage impact and avoid overvoltage damage to the height sensor.

[0054] Figure 2 is a schematic diagram of another overvoltage protection circuit provided in an embodiment of this application. As shown in Figure 2, the overvoltage protection circuit may further include a capacitor C1 and a Zener diode ZD1.

[0055] In one possible implementation, the overvoltage protection circuit further includes a capacitor C1; the source (5) of the field-effect transistor switch Q1 is connected to one end of the capacitor C1, and the other end of the capacitor C1 is connected to one end of the second resistor R2. The capacitor C1 can be used to eliminate interference caused by factors such as static electricity or glitches, reduce the impact on the integrated chip, reduce the impact on the output signal quality, and further improve the safety of the integrated chip and the reliability of the high-sensor.

[0056] In one possible implementation, the overvoltage protection circuit further includes a Zener diode ZD1; the source (5) of the field-effect transistor switch Q1 is connected to the negative terminal of the Zener diode ZD1, and the positive terminal of the Zener diode ZD1 is connected to one end of the second resistor. This Zener diode ZD1 is used to protect other devices in the overvoltage protection circuit, such as the field-effect transistor switch Q1, during circuit connection or conduction in case of voltage instability, thus ensuring the stability of the overvoltage protection circuit.

[0057] In one possible implementation, the field-effect transistor switch Q1 is a P-channel metal-oxide-semiconductor field-effect transistor (MOSFET); the transistor switch Q2 is an NPN transistor. Specifically, the MOSFET switch can be a P-channel MOSFET with a high gate drive voltage threshold and a low body diode voltage. For example, the overvoltage protection circuit may include a MOSFET switch Q1 with a gate drive voltage threshold greater than or equal to 2.5V and a body diode voltage less than or equal to 0.5V, thus ensuring the consistency between the final output target signal and the integrated chip output signal. The transistor switch Q2 can be an NPN transistor, and a model with a low base current and a high gain can be selected. For example, the overvoltage protection circuit may include a transistor switch Q2 with a DC amplification factor (i.e., DC current gain) greater than or equal to 400, thus ensuring the rapid turn-on of the transistor switch Q2 under short-circuit conditions.

[0058] Of course, it should be noted that the field-effect transistor switch Q1 and the transistor switch Q2 in the overvoltage protection circuit can also be of other types, and correspondingly, other circuit connection forms can be adopted. The specific choice can be based on actual needs, and this application embodiment does not limit this.

[0059] In one possible implementation, the first resistor is used to form the voltage difference between the source and gate of the field-effect transistor switch; the second resistor is a grounding resistor.

[0060] Specifically, the first resistor R1 can be used to form the voltage difference between the source (5) and gate (1) of the field-effect transistor switch Q1; the second resistor R2 can be used as a grounding resistor. When the resistance value of the second resistor R2 is small, it is prone to overheating and damage, affecting the overall function of the overvoltage protection circuit. Therefore, the ratio of the first resistor R1 to the second resistor R2 in the overvoltage protection circuit can be greater than a preset ratio (such as 1.5:1) to ensure that a voltage difference can be formed during normal operation. At the same time, the resistance value of the second resistor R2 cannot be too small to avoid thermal damage to the second resistor R2 when the output signal line is short-circuited to 32V and to ensure the stability of the second resistor R2.

[0061] In one possible implementation, the third resistor is used to limit the base current of the transistor switch; the fourth resistor is used to form the voltage difference between the base and emitter of the transistor switch.

[0062] In this embodiment, the third resistor R3 can be used to limit the base current of the transistor switch Q2, ensuring that the transistor switch Q2 will not cause inconsistency between the target signal and the output signal due to conduction during normal operation, and also ensuring that the transistor switch Q2 can conduct when the output signal line is short-circuited to 32V; the fourth resistor R4 can be used to ensure the formation of a voltage difference between the base (4) and emitter (3) of the transistor, thereby ensuring the normal operating range of the transistor Q2. This ensures that the transistor switch Q2 will not conduct when the output signal is high, but will conduct when the output line is short-circuited to the 32V power line, ensuring that the overvoltage protection circuit can achieve the overvoltage protection function without affecting the normal transmission of the signal. In related technologies, the voltage withstand capability of the output voltage signal pin of HALL-IC in the vehicle manufacturing field usually cannot meet the design requirements of direct power supply from the vehicle battery, and the height sensor is at risk of damage in the event of a short circuit in the power line.

[0063] For example, Figure 3 is a schematic diagram of the architecture of a height sensor system in the related art. As shown in Figure 3, the input power of the height sensor is a 5V DC power supply output by the electronic control unit (ECU). The height sensor specifically includes a filter and a Hall effect sensor integrated chip (HALL-IC). The input power of the HALL-IC is a 5V DC power supply, and the output signal of the HALL-IC can be output to the ECU after passing through the filter, realizing signal measurement and output.

[0064] Figure 4 is a schematic diagram of the circuit structure of a height sensor in the related technology. As shown in Figure 4, the circuit of the height sensor is usually composed of a Hall effect sensor integrated chip (HALL-IC) and an auxiliary filter circuit. The core electronic component of the height sensor is the HALL-IC, and the model of the HALL-IC can be selected based on actual needs; this application embodiment does not limit this. The HALL-IC in the height sensor can be used to realize functions such as input / output voltage conversion, sensing of the measured physical quantity, signal conditioning, microcontroller signal calculation and storage, and signal output. In the circuit of the height sensor, an auxiliary filter circuit is arranged around the HALL-IC, which consists of RC filters composed of resistors and capacitors. For example, Figure 4 includes a filter composed of resistor R5, capacitor C2, and capacitor C3, and also includes a filter composed of resistor R6, capacitor C4, and capacitor C5. In this way, the height sensor circuit can obtain better electromagnetic compatibility (EMC) capability and stronger anti-interference capability. The HALL-IC internally includes an operating voltage V. DD Port, common ground voltage V SS Port, output OUT port and decoupling V DEC Port, where the operating voltage V DD The port is an internal power interface, with a common ground voltage of V. SS The port is a grounded power supply interface, decoupling V DEC A decoupling capacitor C6 is connected to the port to accommodate changes in the drive circuit current, avoid mutual coupling interference, and improve the overall stability of the circuit.

[0065] As can be seen from Figures 3 and 4, in the relevant technology, the output signal of the HALL-IC in the height sensor is directly input to the electronic control unit after passing through a filter. In cases such as short circuit between the output line and the power line of the height sensor, the high voltage of the short circuit will impact the output pin of the HALL-IC of the height sensor, which poses a certain risk of damage to the height sensor.

[0066] In this embodiment, an overvoltage protection circuit is provided on the output line of the height sensor HALL-IC to protect the height sensor from overvoltage. For example, Figure 5 shows a schematic diagram of the system architecture of a height sensor provided in this embodiment. As shown in Figure 5, the input power supply of the height sensor is an 8-32V DC power supply output by the electronic control unit (ECU). After passing through a regulated power supply and a filter, the input power supply of the HALL-IC can be a 5V DC power supply, where the regulated power supply is used to stabilize the power supply voltage. The output signal of the HALL-IC is output to the ECU via the overvoltage protection circuit. Thus, the height sensor in this embodiment is equipped with an overvoltage protection circuit, which can achieve overvoltage protection without affecting the normal transmission of the height sensor signal, avoiding damage to the height sensor due to short circuits and ensuring the safety of the height sensor.

[0067] The overvoltage protection circuit in this embodiment effectively improves the overvoltage resistance of the HALL-IC output pins, automatically protecting the signal output line from short circuits and isolating the integrated chip from potential high voltages, thereby improving the height sensor's resistance to output short circuits. In addition, the overvoltage protection circuit is composed of a small number of electronic components, requiring little space and cost, and is easy to design a printed circuit board (PCB), making it flexible for application in height sensors.

[0068] Figure 6 is a schematic flowchart of an overvoltage protection method provided in an embodiment of this application. Referring to Figure 6, this overvoltage protection method is applied to the overvoltage protection circuit in the above embodiment, and may specifically include:

[0069] S601. In the absence of a short circuit, receive the output signal of the integrated chip and output a target signal that is the same as the output signal.

[0070] S602. In the event of a short circuit, the control field-effect transistor switch is turned off to isolate the output pin of the integrated chip from the short-circuit voltage.

[0071] The overvoltage protection method provided in this application embodiment is applied to an overvoltage protection circuit, which specifically includes a field-effect transistor switch, a transistor switch, a first resistor, a second resistor, a third resistor, and a fourth resistor. The drain of the field-effect transistor switch is used to receive the output signal of the integrated chip. The source of the field-effect transistor switch is connected to one end of the first resistor, and the other end of the first resistor is connected to the gate of the field-effect transistor switch. The gate of the field-effect transistor switch and the other end of the first resistor are respectively connected to one end of the second resistor, and the other end of the second resistor is grounded. The collector of the transistor switch is connected to the source of the field-effect transistor switch. The emitter of the transistor switch is connected to one end of the second resistor. The base of the transistor switch is connected to one end of the third resistor and one end of the fourth resistor, respectively. The other end of the third resistor is connected to the source of the field-effect transistor switch, and the other end of the fourth resistor is connected to one end of the second resistor.

[0072] In the absence of a short circuit, the overvoltage protection circuit can receive the output signal from the integrated chip and output the same target signal, ensuring the normal transmission of the height sensor signal. In the event of a short circuit, the control field-effect transistor switch enters the off state, so that the output pin of the integrated chip is isolated from the short-circuit voltage. This can prevent the output voltage pin of the height sensor from being damaged by high voltage, thus improving the safety of the height sensor.

[0073] Furthermore, this application also provides a height sensor, which includes the overvoltage protection circuit described in the above embodiments. The height sensor may also include a Hall-effect integrated circuit (HALL-IC), a filter, a regulated power supply, and other devices; the specific configuration can be based on actual needs, and this application does not limit this.

[0074] Furthermore, this application also provides a vehicle that includes a height sensor, which includes the overvoltage protection circuit described in the above embodiments.

[0075] Furthermore, embodiments of this application also provide a readable storage medium storing a computer program, which, when executed by at least one processor of an electronic device, enables the electronic device to perform the overvoltage protection method provided in the various embodiments described above.

[0076] In addition, this embodiment also provides a chip, which includes a memory and a processor. The memory stores code and data, and the memory is coupled to the processor. The processor runs a program in the memory so that the chip can perform the overvoltage protection method provided in the above-described embodiments.

[0077] Furthermore, this embodiment also provides a program product including a computer program stored in a readable storage medium. At least one processor of an electronic device can read the computer program from the readable storage medium, and the at least one processor executes the computer program to cause the electronic device to implement the overvoltage protection methods provided in the various embodiments described above.

[0078] In addition, this embodiment also provides a computer program, which, when executed by a processor, is used to perform the overvoltage protection method provided in the foregoing various embodiments.

[0079] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0080] In this application, the term "comprising" and its variations can refer to non-limiting inclusion; the term "or" and its variations can refer to "and / or". The terms "first", "second", etc., in this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. In this application, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0081] The above are only some embodiments of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. An overvoltage protection circuit, characterized in that, The overvoltage protection circuit is applied to the height sensor, and the overvoltage protection circuit includes: a field-effect transistor switch, a transistor switch, a first resistor, a second resistor, a third resistor, and a fourth resistor. The drain of the field-effect transistor switch is used to receive the output signal of the integrated chip; the source of the field-effect transistor switch is connected to one end of the first resistor, and the other end of the first resistor is connected to the gate of the field-effect transistor switch; the gate of the field-effect transistor switch and the other end of the first resistor are respectively connected to one end of the second resistor, and the other end of the second resistor is grounded. The collector of the transistor switch is connected to the source of the field-effect transistor switch; the emitter of the transistor switch is connected to one end of the second resistor; the base of the transistor switch is connected to one end of the third resistor and one end of the fourth resistor, respectively; the other end of the third resistor is connected to the source of the field-effect transistor switch; and the other end of the fourth resistor is connected to one end of the second resistor. In the absence of a short circuit, the source output of the field-effect transistor switch is the same as the output signal; in the presence of a short circuit, the transistor switch is in the ON state and the field-effect transistor switch is in the OFF state.

2. The overvoltage protection circuit according to claim 1, characterized in that, When no short circuit occurs and the output signal is high, the field-effect transistor switch is in the ON state, and the target signal output from the source of the field-effect transistor switch is in the high-level state. When no short circuit occurs and the output signal is low, the field-effect transistor switch is in the off state, and the target signal output from the source of the field-effect transistor switch is in the low-level state.

3. The overvoltage protection circuit according to claim 1, characterized in that, In the event of a short circuit, the transistor switch enters the on state, making the gate-source voltage difference of the field-effect transistor switch zero, and the field-effect transistor switch enters the off state.

4. The overvoltage protection circuit according to any one of claims 1 to 3, characterized in that, The overvoltage protection circuit also includes a capacitor; the source of the field-effect transistor switch is connected to one end of the capacitor, and the other end of the capacitor is connected to one end of the second resistor.

5. The overvoltage protection circuit according to any one of claims 1 to 3, characterized in that, The overvoltage protection circuit also includes a Zener diode; the source of the MOSFET switch is connected to the negative terminal of the Zener diode, and the positive terminal of the Zener diode is connected to one end of the second resistor.

6. The overvoltage protection circuit according to any one of claims 1 to 3, characterized in that, The field-effect transistor switch is a P-channel metal-oxide-semiconductor field-effect transistor; the transistor switch is an NPN transistor.

7. The overvoltage protection circuit according to any one of claims 1 to 3, characterized in that, The first resistor is used to form the voltage difference between the source and gate of the field-effect transistor switch; the second resistor is a grounding resistor.

8. The overvoltage protection circuit according to any one of claims 1 to 3, characterized in that, The third resistor is used to limit the base current of the transistor switch; the fourth resistor is used to form the voltage difference between the base and emitter of the transistor switch.

9. An overvoltage protection method, characterized in that, The method is applied to the overvoltage protection circuit according to any one of claims 1 to 8, and the method includes: In the absence of a short circuit, the system receives the output signal from the integrated chip and outputs a target signal that is identical to the output signal. In the event of a short circuit, the control MOSFET switch is turned off, so that the output pin of the integrated chip is isolated from the short circuit voltage.

10. A height sensor, characterized in that, The height sensor includes the overvoltage protection circuit as described in any one of claims 1 to 8.

11. A vehicle, characterized in that, Includes a height sensor, said height sensor comprising the overvoltage protection circuit according to any one of claims 1 to 8.

12. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the overvoltage protection method of claim 9.

13. A chip, characterized in that, The chip includes a memory and a processor. The memory stores code and data and is coupled to the processor. The processor runs the program in the memory so that the chip can perform the overvoltage protection method according to claim 9.

14. A program product, characterized in that, include: A computer program, when the program product is run on a computer, causes the computer to perform the overvoltage protection method of claim 9.

15. A computer program, characterized in that, When the computer program is executed by the processor, it is used to perform the overvoltage protection method as described in claim 9.

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