Protection circuit, electronic control unit and vehicle

Abstract

Provided in the embodiments of the present disclosure are a protection circuit, an electronic control unit and a vehicle. Provided is a protection circuit. The protection circuit comprises a diode, which comprises an anode that is adapted to be connected to an output end of a controller. The protection circuit further comprises a filter unit, which is connected to the ground, and comprises a first end connected to a cathode of the diode and a second end that is adapted to be connected to a first end of a sensor. The protection circuit further comprises a cut-off unit, which comprises a first end connected to the second end of the filter unit, a second end that is adapted to be connected to a second end of the sensor, and a third end connected to the ground. The cut-off unit is configured to be closed when a first voltage applied to the first end of the cut-off unit is less than a predetermined threshold value, and to be open when the first voltage is higher than the predetermined threshold value. In this way, by means of providing in the protection circuit a ground cut-off unit for the sensor, the controller and the sensor can be protected from being damaged due to overvoltage in the event of a high-voltage short circuit.

Description

Protection circuit, electronic control unit and vehicle TECHNICAL FIELD

[0001] The present disclosure relates to the electrical field, and more specifically, to a protection circuit, an electronic control unit and a vehicle. BACKGROUND

[0002] With the global automobile industry accelerating transformation towards low-carbonization and electrification, power system voltage upgrade has become one of the key paths to achieve energy consumption optimization and carbon emission reduction targets. The electronic control units (ECUs) of traditional fuel vehicles and early new energy vehicles are generally designed based on 12-volt power supply architecture. Their power input and electronic component voltage specifications are strictly adapted to the 12-volt environment, which has advantages in cost control and technology maturity, and has long supported the stable operation of automobile electronic systems.

[0003] However, to meet increasingly stringent carbon emission standards, the automobile industry is gradually promoting the application of 48-volt mild hybrid systems and even higher voltage platforms. The 48-volt system can significantly improve the efficiency of electric accessories (such as electronic turbochargers and active suspensions), reduce engine load, and thus directly reduce carbon emissions. SUMMARY

[0004] In a first aspect of the present disclosure, a protection circuit is provided. The protection circuit comprises a diode comprising an anode adapted to be connected to an output of a controller. The protection circuit further comprises a filter unit connected to a ground and comprising a first end connected to a cathode of the diode and a second end adapted to be connected to a first end of a sensor. The protection circuit further comprises a cut-off unit comprising a first end connected to the second end of the filter unit, a second end adapted to be connected to a second end of the sensor, and a third end connected to the ground. The cut-off unit is configured to be closed if a first voltage applied to the first end of the cut-off unit is less than a predetermined threshold, and to be opened if the first voltage is higher than the predetermined threshold.

[0005] In a second aspect of the present disclosure, an electronic control unit is provided. The electronic control unit comprises a controller comprising an output. The electronic control unit further comprises the protection circuit according to the first aspect of the present disclosure. The anode of the diode of the protection circuit is connected to the output of the controller.

[0006] In a third aspect of the present disclosure, a vehicle is provided, comprising the electronic control unit according to the second aspect of the present disclosure.

[0007] It should be understood that the description in the summary is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become readily apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0008] The above-described and other features, advantages, and aspects of the present disclosure will become more apparent as various embodiments of the present disclosure are described in greater detail below. In the drawings, like reference numerals refer to like elements throughout the various figures and embodiments of the present disclosure, wherein:

[0009] FIG. 1 illustrates a schematic diagram of an example controller system, in accordance with some embodiments of the present disclosure;

[0010] FIG. 2 illustrates a schematic diagram of an example controller system, in accordance with some embodiments of the present disclosure; and

[0011] FIG. 3 illustrates a schematic diagram of an example controller system, in accordance with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0012] Various embodiments are now described with reference to the drawings. Throughout the various drawings, like reference numerals are used to refer to like elements throughout the various figures and embodiments of the present disclosure, wherein:

[0013] Reference to“an embodiment” or“one embodiment” in the framework of this description means that a particular configuration, structure, or characteristic described in relation to the embodiment is included in at least one embodiment. Thus, phrases such as“in an embodiment” or“in one embodiment” that can occur at various locations throughout the description do not necessarily refer to the same embodiment. Furthermore, in one or more embodiments, a particular configuration, structure, or characteristic can be combined in any appropriate manner.

[0014] In the following disclosure, unless otherwise indicated, when referring to an absolute position modifier such as the terms“front,”“back,”“top,”“bottom,”“left,”“right,” etc., or a relative position modifier such as the terms“above,”“below,”“higher,”“lower,” etc., or when referring to an orientation modifier such as“horizontal,”“vertical,” etc., reference is made to the orientation shown in the figures.

[0015] In the following description, one or more specific details are described to provide an example embodiment of the description. One or more other embodiments of the description can be devoid of one or more of the specific details, or can include other structures, materials, or components. In other instances, well-known structures, materials, or operations have not been shown or described in detail to avoid obscuring aspects of the embodiments.

[0016] The transition from 12-volt systems to 48-volt systems also presents technical compatibility challenges. On the one hand, traditional 12-volt architecture ASICs, whose hardware design (such as voltage-resistant circuits, power management modules) cannot directly withstand 48-volt input, and forced adaptation can cause component burnout and system failure. On the other hand, the electronic systems of modern cars are highly complex, containing hundreds of wire harness interfaces, sensor connectors, etc., and the risk of short circuit under long-term vibration, aging, or mechanical stress cannot be ignored. For example, if a 12-volt component interface accidentally shorts with a 48-volt power supply, the instantaneous overvoltage will directly break through the electronic components, causing ECU failure, and even affecting vehicle safety.

[0017] For example, in a conventional airbag (AB) system, there is an AB ECU and a sensor that complies with the peripheral sensor interface (PSI) protocol, and if the PSI interface is shorted with 48V, both will be damaged.

[0018] In order to achieve a smooth transition from 12-volt to 48-volt power supply systems and ensure that the ECU system can meet the performance and environmental protection requirements of future cars, in-depth research and development are needed on existing technologies and designs. This includes developing new ASIC designs, improving power management systems, and optimizing the overall ECU system architecture to adapt to higher voltage working environments.

[0019] In related technologies, in order to protect the circuit from being shorted to 48V, the PSI interface of the AB ECU can be protected by adding a backup protection diode, but the PSI sensor cannot be protected in this way.

[0020] Therefore, embodiments of the present disclosure provide a circuit for protecting a sensor by setting a ground cut-off circuit. The protection circuit is composed of a diode on the high-voltage side and a cut-off unit on the low-voltage side. The anode of the diode is connected to the output end of the controller, and the cathode is connected to the first end of the filter unit. The second end of the filter unit is connected to the first end of the sensor. The first end of the cut-off unit is also connected to the second end of the filter unit, the second end is connected to the second end of the sensor, and the third end is directly grounded.

[0021] According to embodiments of the present disclosure, when the voltage applied to the first end of the cut-off unit, i.e. the first end of the sensor, is less than a predetermined threshold, the cut-off unit is closed, so that the protection circuit forms a loop between the controller and the sensor to achieve normal operation. When the voltage applied to the first end of the cut-off unit, i.e. the first end of the sensor, is greater than the predetermined threshold, for example, the first end of the sensor is short-circuited to a voltage greater than the predetermined threshold, on the one hand, the diode can achieve overvoltage protection for the controller; on the other hand, the cut-off unit disconnects the loop between the sensor and the ground, so that the resistance in the loop of the sensor becomes infinite, avoiding damage to the sensor by high voltage.

[0022] Fig. 1 shows a schematic diagram of an example controller system 1 according to some embodiments of the present disclosure. As shown in Fig. 1, the controller system 1 comprises an electronic control unit 10. The electronic control unit 10 may, for example, be an airbag ECU of an airbag system. The controller system 1 further comprises one or more sensors 20 in data transmission with the control unit 10. The one or more sensors 20 can comprise an interface complying with the Peripheral Sensor Interface (PSI) protocol, and the output N1 of the controller 200 also complies with the PSI protocol.

[0023] The protection circuit 100 implements protection by monitoring the voltage on the sensor 20 line. The protection circuit 100 comprises a network consisting of a diode 110, a filter unit 130 and a cut-off unit 120. The anode of the diode 110 is connected to the output N1 of the controller 200, and the cathode is connected to the first end N31 of the filter unit 130. Its function is reverse blocking protection. For example, when a reverse high voltage such as 48V short circuit occurs on the subsequent circuit such as the sensor side, the diode unidirectional conduction characteristic can block the reverse conduction of high voltage to the controller, avoiding damage to the controller by overvoltage.

[0024] The first end N31 of the filter unit 130 is connected to the cathode of the diode 110 and receives the signal through the diode. In addition, the filter unit 130 can filter the signal output by the controller or the signal transmitted by the sensor, reducing high-frequency noise interference. Then, the second end N32 of the filter unit 130 is connected to the first end N2 of the sensor 20, so as to transmit the filtered signal to the sensor 20.

[0025] The cut-off unit 120 is a protection execution component of the circuit, which controls the on-off of the loop by detecting the voltage threshold. The first end N21 of the cut-off unit 120 is connected to the second end N32 of the filter unit 130, for detecting the voltage at this node, defined as "first voltage". The second end N22 of the cut-off unit 120 is connected to the second end N3 of the sensor 20, and the third end N23 of the cut-off unit 120 is grounded.

[0026] In some embodiments, when the "first voltage" (voltage at the first end N2 of the sensor 20) is less than a predetermined threshold (such as a normal operating 12V or 36V system voltage range), the cutoff unit 120 is closed, the sensor 20 ground loop is turned on, and the entire controller system 1 is ensured to operate normally. For example, when the first end N2 of the sensor 20 is shorted to the high voltage voltage source 30 (such as a 48V short circuit occurs), i.e., the "first voltage" is higher than the predetermined threshold, the cutoff unit 120 is opened, and the sensor 20 ground loop is cut off, thereby avoiding overvoltage from forming a loop through the sensor and causing damage. According to the embodiment shown in FIG. 1, the combination of diode reverse blocking and cutoff unit threshold control is used to achieve bidirectional overvoltage protection for the controller and sensor. It should be understood that the high voltage 48V mentioned in the present disclosure is only exemplary. The high voltage can be any other voltage higher than the predetermined threshold.

[0027] FIG. 2 shows a schematic diagram of an example controller system 1 according to some embodiments of the present disclosure. As shown in FIG. 2, the controller system 1 includes an electronic control unit 10, and one or more sensors 20 that perform data transmission with the electronic control unit 10. The anode of the diode 110 is connected to the output end N1 of the controller 200, and the cathode is connected to the first end N31 of the filter unit 130. The diode 110 has the basic characteristic of unidirectional conduction, i.e., only allows current to flow from the anode (controller 200 side) to the cathode (sensor 20 side), and blocks the reverse direction. In this way, the reverse current or voltage that may be generated on the sensor side can be prevented from impacting the controller 200.

[0028] The first end N31 of the filter unit 130 is connected to the cathode of the diode, and the second end N32 is connected to the first end N2 of the sensor 20 and the first end N21 of the cutoff unit 120. In some embodiments, the filter unit 130 can include an RC circuit formed by a resistor and a capacitor, or an LC circuit formed by an inductor and a capacitor. In such embodiments, the filter unit 130 can filter out high-frequency noise and glitches in the signal line.

[0029] The first end N21 of the cutoff unit 120 is connected to the second end N32 of the filter unit 130 and the first end N2 of the sensor 20, serving as a voltage detection point. The second end N22 of the cutoff unit 120 is connected to the second end N3 of the sensor 20. Generally, the second end of the sensor 20 is a ground or power return path. The third end (N23) of the cutoff unit 120 is directly connected to the ground.

[0030] According to the embodiment shown in FIG. 1, for example, when a higher voltage short circuit occurs at the sensor interface, neither the controller nor the sensor will be damaged by the overvoltage, ensuring reliable operation of the controller and sensor in a high voltage scenario, and avoiding the entire vehicle electronic system from being paralyzed due to ECU failure.

[0031] As shown in FIG. 2, the cut-off unit 120 includes a switch 121 and a control module 122. The switch 121 controls the on-off of the sensor 20 grounding loop under the control of the control module 122. The first end N24 is connected to the second end N22 of the cut-off unit 120, i.e. the detection voltage node. The second end N25 of the switch 121 is connected to the third end N23 of the cut-off unit 120, i.e. the ground. The control end N26 receives the signal of the control module 122 to perform the closing / opening of the switch 121 according to the signal. The control module 122 outputs the first voltage control signal. The first end N27 of the control module 122 is connected to the first end N21 of the cut-off unit to detect the first voltage in real time. The second end N28 of the control module 122 is connected to the control end N26 of the switch 121 to output the control signal.

[0032] During operation, when the control module 122 detects that the first voltage is lower than the predetermined threshold, the control module 122 outputs the first control signal, such as high level, to make the switch closed. When the first voltage is higher than the predetermined threshold, the control module 122 outputs the second control signal, such as low level, to make the switch opened. In order to perform the corresponding control logic, the control module 122 includes a second switch 123. The first end of the second switch 123 is connected to the second end N28 of the control module, i.e. the control end of the switch 121 and the voltage source V which can provide a gate drive voltage for example. The control end of the second switch 123 is connected to the first end N27 of the control module 122, i.e. the detection voltage node. The second end of the second switch 123 is grounded.

[0033] In the shown embodiment, the second switch 123 can change the voltage of the control end of the switch 121 by itself on-off. When the first voltage is lower than the predetermined threshold, the second switch 123 is opened, and the voltage source provides the high level first control signal to the control end of the switch 121 through the first end, so that the switch 121 is closed. When the first voltage is higher than the predetermined threshold, the second switch is closed to pull the control end of the switch 121 to the ground level second control signal, so that the switch 121 is opened.

[0034] In some embodiments, when the first voltage is less than the predetermined threshold, such as the 36V system voltage range in normal operation, the cut-off unit 120 is closed, the sensor 20 grounding loop is conducted, and the normal operation is ensured. Conversely, when the first voltage is higher than the predetermined threshold, such as when a 48V short circuit occurs, the cut-off unit 120 is opened, the sensor grounding loop is cut off, and the damage caused by the overvoltage forming a loop through the sensor is avoided.

[0035] FIG. 3 shows a schematic diagram of an example controller system 1 according to some embodiments of the present disclosure. As shown in FIG. 3, the controller system 1 includes an electronic control unit 10, and one or more sensors 20 for data transmission with the control unit 10. The one or more sensors 20 can be PSI sensors with an interface complying with the PSI protocol, for example.

[0036] The electronic control unit 10 comprises a controller 200 and a protection circuit 100. The controller 200 can be a processing chip, for example. As shown in FIG. 3, the controller 200 comprises a complementary MOS circuit, i.e. MOS M1 and MOS M2 with their sources connected together. The gates of the two MOS transistors are used to receive control signals, such as a synchronization pulse signal.

[0037] The protection circuit 100 comprises a diode D1. The anode of the diode D1 is connected to the output of the controller 200, and the cathode of the diode D1 is connected to the first end of the filter unit 130. The diode D1 has the basic property of unidirectional conduction, i.e. only allows current to flow from the anode (controller 200 side) to the cathode (sensor 20 side), and blocks the reverse direction. In this way, the controller 200 can be protected from the reverse current or voltage impact that can be generated at the sensor side.

[0038] The filter unit 130 is an RC filter network. The filter unit 130 comprises a capacitor C1 (also referred to as a third capacitor). The first end of the capacitor C1 is connected to the first end of the filter unit 130 and the first end of a resistor R1 (also referred to as a third resistor), and the second end of the capacitor C1 is connected to ground. The second end of the third resistor R1 of the filter unit 130 is connected to the second end of the filter unit 130 and the first end of a capacitor C2. The second end of the capacitor C2 (also referred to as a fourth capacitor) of the filter unit 130 is connected to ground.

[0039] In the embodiment shown in FIG. 3, the capacitor C1, the resistor R1 and the capacitor C2 form a "pi" type RC filter circuit. For example, the capacitor C1 can filter out the high-frequency noise in the signal present at the input, i.e. at the filter unit 130. The resistor R1 can achieve current limiting and damping, and cooperate with the capacitor C1 and the capacitor C2 to suppress high-frequency resonance. The capacitor C2 can further filter out the residual noise, and finally output a smooth signal to the sensor 20, reducing the interference of noise on the sensor and subsequent circuits. In such an embodiment, by providing a pi type filter, the filtering effect on different frequency bands of noise can be enhanced, and the signal integrity can be improved.

[0040] The first end of the cutting unit 120 is connected to the second end of the filter unit 130 and the first end N2 of the sensor 20 as a voltage detection point. The second end of the cutting unit 120 is connected to the second end of the sensor 20. The third end N23 of the cutting unit 120 is directly connected to the ground. As shown in FIG. 3, the cutting unit 120 includes an N-channel metal oxide semiconductor field effect transistor (NMOS) Q1 corresponding to the switch 121 shown in FIG. 2. The source of the NMOS corresponds to the first end N23 of the switch 121. The drain of the NMOS corresponds to the second end N24 of the switch 121. The gate of the NMOS corresponds to the control end N25 of the switch 121. In addition, the switch 121 further includes a first capacitor C3. The first end of the first capacitor C3 is connected to the source of the NMOS, and the second end of the first capacitor C3 is connected to the gate of the NMOS.

[0041] The circuit module corresponding to the control module 122 in FIG. 2 includes a transistor Q2, a resistor R2 (also referred to as a first resistor), a resistor R3 (also referred to as a second resistor), a voltage stabilizing diode D2, a resistor R4, and a resistor R5. The circuit module corresponding to the second switch 123 of the control module 122 includes: a transistor Q2, a resistor R2, and a resistor R3. The first end of the resistor R2 corresponds to the control end of the second switch 123 and is connected to the first end of the sensor 20. The second end of the resistor R2 is connected to the first end of the resistor R3 and the base of the transistor Q2. The second end of the resistor R3 is connected to the ground. The collector of the transistor Q2 corresponds to the first end of the second switch 123. The emitter of the transistor Q2 is the second end of the second switch 123. In addition, the circuit module corresponding to the second switch 123 of the control module 122 further includes a capacitor C4 (also referred to as a first capacitor). The first end of the capacitor C4 is connected to the base of the transistor Q2, and the second end of the capacitor C4 is connected to the ground.

[0042] The circuit module corresponding to the control module 122 in FIG. 2 can also include a voltage stabilizing circuit. The voltage stabilizing diode D2 and the resistor R5. The cathode of the voltage stabilizing diode D2 is connected to the second end N32 of the filter unit 130, and the anode of the voltage stabilizing diode D2 is connected to the first end N21 of the cutting unit 120. That is, the voltage stabilizing diode D2 is connected in series on the line between the filter unit 130 and the sensor 20. Thus, when the first end of the sensor 20 is shorted to a high voltage, the voltage stabilizing diode D2 can limit the high voltage to a fixed voltage value, which helps the design of subsequent circuits and improves the stability of the circuit.

[0043] In this embodiment, NMOS Q1 controls the ground loop of sensor 20. The gate is controlled by transistor Q2, and the source of NMOS Q1 is grounded, with the drain connected to the ground terminal of the sensor. In normal operation, since the interface voltage of sensor 20 is below the threshold value, and the voltage divided by resistor R2 and resistor R3 is not enough to turn on transistor Q2, Q2 is off. Voltage VI through R4 makes the gate of NMOS Q1 receive a high level, so that the voltage between the gate and the source of NMOS Q1 is higher than the voltage threshold, so that NMOS Q1 is turned on, and the sensor ground loop is normal. Conversely, when the interface voltage of sensor 20 exceeds the threshold value, the high voltage reaches the base of transistor Q2 after being limited by voltage stabilizing diode D2 and being divided by resistor R2 and resistor R3, so that transistor Q2 is turned on. As a result, the gate of NMOS Q1 is pulled low, so that the voltage between the gate and the source of NMOS Q1 is less than the voltage threshold, i.e. the turn-on condition is no longer met, so that NMOS Q1 is turned off, cutting off the sensor ground loop and forming a high-impedance state to protect sensor 20. The working principle of the entire sensor system will be described below as a whole.

[0044] In a normal state, the control signal S (such as a synchronization pulse signal) of controller 200 triggers the conduction of MOS M1 and M2, and power V is output. Diode D1 is forward-biased, and the signal is transmitted to sensor 20 after RC filtering. At this time, since the voltage at the base of transistor Q2 is not enough to turn it on, transistor Q2 is off. As discussed above, NMOS Q1 is turned on, the sensor ground loop is normal, and the system works stably.

[0045] In an overvoltage fault, for example, when the first end of sensor 20 is short-circuited to 48V, the voltage at the first end of sensor 20 as the first voltage rises sharply, and the voltage divided by resistor R2 and resistor R3 turns on transistor Q2, pulling down the voltage at the gate of NMOS Q1, and NMOS Q1 is turned off, cutting off the sensor ground loop. At the same time, diode D1 is off, blocking the conduction of high voltage to control unit 200. Finally, both the sensor and the control unit are in a protected state, avoiding overvoltage damage.

[0046] According to the embodiment shown in FIG. 3, the protection circuit 100 realizes reliable protection of the sensor interface, for example, in the vehicle 12V / 48V voltage upgrade scenario, through the multi-layer protection of reverse blocking, RC filtering and threshold cutting, while taking into account signal integrity and device safety.

[0047] Details and embodiments can vary, even significantly, with respect to what is described by way of example only, without departing from the scope of protection. Various embodiments described above can be combined to provide further embodiments. Aspects of the embodiments can be modified, if necessary, to employ the concepts of various patents, applications, and publications to provide yet further embodiments.

[0048] These and other changes can be made to the embodiments in light of the above Detailed Description. The terms used in the following claims should not be construed to limit the claims to the specific embodiments disclosed in the Specification and the claims. Such terms are intended to cover all their possible embodiments and should be interpreted as encompassing by way of example the various embodiments described herein that constitute the preferred solutions over the prior art.

Claims

1. A protection circuit (100), comprising: a diode (110) comprising an anode adapted to be connected to an output (N1) of a controller (200); a filtering unit (130) for filtering a signal and comprising a first end (N31) connected to a cathode of the diode (110) and a second end (N32) adapted to be connected to a first end (N2) of a sensor (20); and a cut-off unit (120) comprising a first end (N21) connected to the second end (N32) of the filtering unit (130), a second end (N22) adapted to be connected to a second end (N3) of the sensor (20) and a third end (N23) connected to ground, wherein the cut-off unit (120) is configured to be closed in case a first voltage applied at the first end (N21) of the cut-off unit (120) is lower than a predetermined threshold and to be opened in case the first voltage is higher than the predetermined threshold.

2. The protection circuit (100) according to claim 1, wherein the cut-off unit (120) further comprises: a switch (121) comprising a first end (N24) connected to the second end (N22) of the cut-off unit (120), a second end (N25) connected to the third end (N23) of the cut-off unit (120); and a control module (122) comprising a first end (N27) connected to the first end (N21) of the cut-off unit (120) and a second end (N28) connected to a control end (N26) of the switch (121), wherein the control module (122) is configured to send a first control signal indicative of a closing to the control end (N26) of the switch (121) in case the first voltage is lower than the predetermined threshold and to send a second control signal indicative of an opening to the control end (N26) of the switch (121) in case the first voltage is higher than the predetermined threshold.

3. The protection circuit (100) according to claim 2, wherein the switch (121) comprises: a N-type metal oxide semiconductor field effect transistor, NMOS, the first end (N23) of the switch (121) being a source of the NMOS, the second end (N24) of the switch (121) being a drain of the NMOS and the control end (N25) of the switch (121) being a gate of the NMOS.

4. The protection circuit (100) according to claim 3, wherein the switch (121) further comprises: a first capacitor (C3), wherein a first end of the first capacitor (C3) is connected to the source of the NMOS and a second end of the first capacitor (C3) is connected to the gate of the NMOS.

5. The protection circuit (100) according to claim 2, wherein the control module (122) comprises: ​ a second switch (123) comprising a first terminal connected with the second terminal (N28) of the control module (122) and a voltage source, a control terminal connected with the first terminal (N27) of the control module (122), and a second terminal connected with ground, wherein the second switch (123) is configured to be open in case that the first voltage is lower than the predetermined threshold value, so that the control module (122) sends the first control signal, and to be closed in case that the first voltage is higher than the predetermined threshold value, so that the control module (122) sends the second control signal.

6. The protection circuit (100) according to claim 5, wherein the second switch (123) comprises: a transistor (Q2), a first resistor (R2) and a second resistor (R3), wherein a first terminal of the first resistor (R2) is the control terminal of the second switch (123), a second terminal of the first resistor (R2) and a first terminal of the second resistor (R3) are connected with the base of the transistor (Q2), a second terminal of the second resistor (R3) is connected with ground, a collector of the transistor (Q2) is the first terminal of the second switch (123), and an emitter of the transistor (Q2) is the second terminal of the second switch (123).

7. The protection circuit (100) according to claim 6, wherein the control module (122) further comprises: a first capacitor (C4), wherein a first terminal of the first capacitor (C4) is connected with the base of the transistor (Q2), and a second terminal of the first capacitor (C4) is connected with ground.

8. The protection circuit (100) according to claim 1, further comprising: a zener diode (D2), wherein a cathode of the zener diode (D2) is connected with the second terminal (N32) of the filter unit (130), and an anode of the zener diode (D2) is connected with a first terminal (N21) of the cut-off unit (120).

9. The protection circuit (100) according to claim 1, wherein the filter unit (130) comprises: a third capacitor (C1), a third resistor (R1), a fourth capacitor (C2), wherein a first terminal of the third capacitor (C1) and a first terminal of the third resistor (R1) are connected with a first terminal of the filter unit (130), a second terminal of the third capacitor (C1) is connected with ground, a first terminal of the fourth capacitor (C2) is connected with a second terminal of the filter unit (130), and a second terminal of the fourth capacitor (C2) is connected with a third terminal of the filter unit (130) and ground.

10. An electronic control unit (10), comprising: a controller (200) comprising an output terminal (N1); and the protection circuit (100) according to any one of claims 1 to 9, wherein an anode of the diode (110) of the protection circuit (100) is connected with the output terminal (N1) of the controller (200). ​ 11. The electronic control unit (10) according to claim 10, wherein said output (N1) comprised by said controller (200) complies with the Peripheral Sensor Interface, PSI, protocol.

12. A vehicle comprising an electronic control unit (10) according to claim 10 or 11.

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