Cut-off switch device for an in-vehicle voltage network of a vehicle

Abstract

To provide a breaking switch device for an on-vehicle voltage network and a method therefor for providing information related to a current flowing in an on-vehicle voltage network without causing extra energy consumption.SOLUTION: A breaking switch device 16 for an on-vehicle voltage network 10 of a vehicle for selectively connecting a voltage source 12 to a load 14 and separating the voltage source from the load, includes: a voltage source connection region 18 and a load connection region 20; and a plurality of MOSFET breaking switch elements 22, 24, 26, 28, 30 that are connected between the voltage source connection region and the load connection region in parallel. At least one MOSFET breaking switch element 22 of the plurality of MOSFET breaking switch elements is configured as a current monitoring breaking switch element that supplies an amount of current representing a current flowing between the voltage source connection region and the load connection region, and at least one MOSFET breaking switch element of the plurality of MOSFET breaking switch elements is not configured as a current monitoring breaking switch element.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a disconnect switch device for an in-vehicle voltage network of a vehicle for selectively connecting a voltage source to a load and disconnecting the voltage source from the load.

Background Art

[0002] For the purpose of being able to detect the occurrence of overcurrent or short circuit in the in-vehicle voltage network of a vehicle, as is known from German Patent Application Publication No. 102019108541, for example, it is known to incorporate a current measurement unit into this type of in-vehicle voltage network. In the case of this current measurement unit, one shunt resistor is connected between two busbars. For the purpose of detecting the current flowing through the shunt resistor, two measurement conductor paths are assigned to this shunt resistor, and through these measurement conductor paths, the voltage drop across the shunt resistor can be detected, and thus the current flowing through this shunt resistor can also be detected. If the load current is high, a relatively large power loss occurs in this type of low-resistance shunt resistor, while if the current is small, the measured value has to be amplified in an operational amplifier to a signal level at which it can be evaluated, and such an operational amplifier also causes additional energy consumption.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The problem of the present invention is to provide a disconnect switch device for an in-vehicle voltage network of a vehicle that can provide information about the current flowing in the in-vehicle voltage network in a simple and reliable manner without substantially causing additional energy consumption.

Means for Solving the Problems

[0004] According to the present invention, this problem is solved by a cut-off switch device for an in-vehicle voltage network of a vehicle as follows for selectively connecting a voltage source to a load and disconnecting the voltage source from the load. That is, this cut-off switch device includes a voltage source connection region and a load connection region, and a plurality of MOSFET cut-off switch elements connected in parallel with each other between the voltage source connection region and the load connection region. At least one of the plurality of MOSFET cut-off switch elements is configured as a current monitoring cut-off switch element that supplies a current amount representing the current flowing between the voltage source connection region and the load connection region, and at least one of the plurality of MOSFET cut-off switch elements is not configured as a current monitoring cut-off switch element.

[0005] The cut-off switch device configured according to the present invention uses different types of MOSFET cut-off switch elements. The MOSFET cut-off switch elements not configured as current monitoring cut-off switch elements substantially form load switches, and during the operation of the vehicle, that is, when the load is connected to the voltage source, most of the current flows through these load switches. At least one MOSFET cut-off switch element configured as a current monitoring cut-off switch element, generally referred to as an IPS (Intelligent Power Switch), also guides a part of the current flowing between the voltage source and the load during operation, but guides only a significantly smaller part than one or more MOSFET cut-off switch elements that are not configured as current monitoring cut-off switch elements and operate as load switches. This part of the current in the whole current is large enough to ensure the accurate detection of the current flowing through at least one MOSFET cut-off switch element configured as a current monitoring cut-off switch element, while on the other hand, it is also small enough to ensure that it basically does not exceed the allowable short-circuit current of this type of MOSFET cut-off switch element configured as a current monitoring cut-off switch element even in the case of a high load.

[0006] In a simply constructed and cost - free structure, for the purpose of being able to provide the information required regarding the current level, it is proposed that only one MOSFET cutoff switch element is configured as a current - monitoring cutoff switch element and / or a plurality of MOSFET cutoff switch elements are not configured as current - monitoring cutoff switch elements.

[0007] In the case of a cutoff switch device configured according to the present invention, each of the MOSFET cutoff switch elements can have a voltage - source terminal connected to the voltage - source connection region, preferably the drain terminal, a load terminal connected to the load connection region, preferably the source terminal, and a gate terminal connected to the control unit.

[0008] For the purpose of minimizing the power loss in the cutoff switch device as much as possible, at least one MOSFET cutoff switch element configured as a current - monitoring cutoff switch element has a current - monitoring cutoff switch element resistance between the voltage - source terminal and the load terminal of this element in the conducting state of this element that connects the voltage source to the load, and at least one MOSFET cutoff switch element not configured as a current - monitoring cutoff switch element has a MOSFET cutoff switch element resistance between the voltage - source terminal and the load terminal of this element in the conducting state of this element that connects the voltage source to the load, and it is proposed that the current - monitoring cutoff switch element resistance is greater than the MOSFET cutoff switch element resistance.

[0009] Particularly in this case, if the ratio of the total MOSFET cutoff switch element resistance formed by all MOSFET cutoff switch elements not configured as current - monitoring cutoff switch elements to the total current - monitoring cutoff switch element resistance formed by all MOSFET cutoff switch elements configured as current - monitoring cutoff switch elements is within the range of 0.05 to 0.15, a configuration can be achieved that is intended to have a large enough current flow to accurately detect through at least one current - monitoring cutoff switch element.

[0010] For the purpose of protecting at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element from overcurrent, this MOSFET cutoff switch element can include an overcurrent protection circuit. If the current between the voltage source terminal and the load terminal of at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element exceeds the threshold current, the overcurrent protection circuit is configured to switch at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element to a state of disconnecting the voltage source from the load or to maintain this state.

[0011] Furthermore, for the purpose of protecting at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element from overheating, this MOSFET cutoff switch element can include an overheat protection circuit. If the temperature of at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element exceeds the threshold temperature, the overheat protection circuit is configured to switch at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element to a state of disconnecting the voltage source from the load or to maintain this state.

[0012] For the purpose of enabling the current flowing between the voltage source and the load to be selectively guided through at least one current monitoring cutoff switch element, it is proposed that at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element can be switched between a state of connecting the voltage source to the load and a state of disconnecting the voltage source from the load, preferably without depending on any MOSFET cutoff switch element that is not configured as a current monitoring cutoff switch element and without depending on at least one MOSFET cutoff switch element.

[0013] What can be proposed for a structure that can be easily realized in terms of circuit technology is that all MOSFET cutoff switch elements not configured as current monitoring cutoff switch elements can be switched together between a state of connecting a voltage source to a load and a state of disconnecting the voltage source from the load. Therefore, it is not necessary to control these MOSFET cutoff switch elements independently of each other.

[0014] In order to accurately detect the current flowing between the voltage source and the load, for the purpose of avoiding a temperature difference from occurring between various MOSFET cutoff switch elements, the voltage source connection region includes a bus bar, preferably a copper bus bar, that is conductively connected to and thermally conductive to all MOSFET cutoff switch elements, and / or the load connection region includes a bus bar, preferably a copper bus bar, that is conductively connected to and thermally conductive to all MOSFET cutoff switch elements, is proposed.

[0015] The present invention further relates to an in-vehicle voltage network for a vehicle, the in-vehicle voltage network including a voltage source and a load to which electrical energy is to be supplied from the voltage source, and further including a cutoff switch device configured according to the present invention, wherein the voltage source connection region of the cutoff switch device is connected to the voltage source and the load connection region is connected to the load.

[0016] Furthermore, the present invention relates to a method for operating this type of in-vehicle voltage network. According to this method, in the low-load operating state of the in-vehicle voltage network, at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element is switched to a state of connecting the voltage source to the load, and at least one MOSFET cutoff switch element not configured as a current monitoring cutoff switch element is switched to a state of disconnecting the voltage source from the load. This type of low-load operating state can be, for example, the parking state of the vehicle. In the parking state, the load is substantially formed by consumer devices such as warning equipment or other security systems. Such consumer devices impose only a small load on the in-vehicle voltage network, and thus, similarly, only a current flow that does not overload at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element is generated. In this state, since the entire current flows through at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element, a relatively high detection accuracy of the current flow through this current monitoring cutoff switch element can be achieved.

[0017] Preferably, what is proposed in the method according to the present invention is that in the low-load operating state, any MOSFET cutoff switch element configured as a current monitoring cutoff switch element is switched to a state of connecting the voltage source to the load, and / or any MOSFET cutoff switch element not configured as a current monitoring cutoff switch element is switched to a state of disconnecting the voltage source from the load.

[0018] For example, when a higher load occurs due to the switching on of a parking heater or other electrical energy-consuming devices, in order to avoid overloading at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element, in the low-load operating state, when all MOSFET cutoff switch elements not configured as current monitoring cutoff switch elements are switched to a state of disconnecting the voltage source from the load, if the amount of current supplied by at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element represents a current exceeding the threshold current and / or represents a change in current over time exceeding the threshold current gradient, then at least a part, preferably all, of the MOSFET cutoff switches not configured as current monitoring cutoff switch elements are switched to a state of connecting the voltage source to the load.

[0019] It is further proposed for the purpose of ensuring that information regarding the current flowing between the voltage source and the load can be obtained in any operating state of the in-vehicle voltage network of a vehicle in which the load should be powered from the voltage source. When the cutoff switch device should connect the voltage source to the load, at least, at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element is switched to a state of connecting the voltage source to the load.

[0020] Next, the present invention will be described in detail with reference to the accompanying drawings showing the circuit diagram of the cutoff switch device in the in-vehicle voltage network of a vehicle.

Brief Description of the Drawings

[0021]

Figure 1

Embodiments for Carrying Out the Invention

[0022] FIG. 1 shows a partial region of an in-vehicle voltage network of a vehicle, generally designated by reference numeral 10. The portion of the in-vehicle voltage network 10 shown in FIG. 1 includes a voltage source 12, a load 14 including a plurality of electrical energy consuming devices, and a disconnect switch device 16 that selectively connects or disconnects the voltage source 12 from the load 14. The disconnect switch device 16 includes a voltage source connection region 18 connected to the voltage source 12, for example, the positive electrode of a battery or accumulator, and a load connection region 20 connected to the load 14.

[0023] The disconnect switch device 16 further includes a plurality of MOSFET disconnect switch elements 22, 24, 26, 28, 30. Each of the MOSFET disconnect switch elements 22, 24, 26, 28, 30 includes a voltage source terminal 32, a load terminal 34, and a gate terminal 36. If the MOSFET disconnect switch elements 22, 24, 26, 28, 30 are configured as n-channel MOSFETs, the voltage source connection region 32 may be formed substantially by or connected to the drain terminal, while the load connection region 34 may be formed substantially by or connected to the source terminal.

[0024] In the case of the disconnect switch device 16 shown in FIG. 1, the MOSFET disconnect switch element 22 is configured as a current monitoring disconnect switch element, which supplies a current amount representing the current flowing between the voltage source terminal 32 and the load terminal 34 of this element via a load current detection circuit 38 and transmits this information to, for example, a control unit 40.

[0025] The MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element further includes an overcurrent protection circuit 42. A current amount is also supplied to this circuit, and based on this current amount, the overcurrent protection circuit 42 identifies whether the current flowing between the voltage source terminal 32 and the load terminal 34 is above or below the maximum allowable short-circuit current. When the maximum allowable short-circuit current is reached or exceeded, the overcurrent protection circuit 42 controls the gate control unit or the charge carrier pump 44 of the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element so that the conductive connection between the voltage source terminal 32 and the load terminal 34 is interrupted, and the MOSFET cutoff switch element 22 is switched to the state where this element disconnects the voltage source 12 from the load 14.

[0026] Similarly, the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element includes an overheat protection circuit 46. Information regarding the temperature in the region of the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element is supplied to this circuit from the temperature sensor 48. When this temperature exceeds the allowable temperature threshold, similarly, the gate control unit 44 is controlled so that the conductive connection between the voltage source terminal 32, i.e., the drain terminal, and the load terminal 34, i.e., the source terminal, is interrupted.

[0027] For the purpose of being able to basically switch the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element between a conductive state, i.e., a state where this element connects the voltage source 12 to the load 14, and an open state of this element, i.e., a state where the voltage source 12 is disconnected from the load 14, the gate control unit 44 is controllably connected to the control unit 40, and the control unit 40, for the purpose of establishing the conductive state of the MOSFET switch 50 that forms a basic component of the MOSFET cutoff switch element 22 as required, depends on the operation of the load 14 required in the vehicle or the individual electrical energy-consuming devices of this load, and sends a corresponding control signal to the gate control unit 44.

[0028] The further MOSFET cutoff switch elements 24, 26, 28, 30 are not configured as current monitoring cutoff switch elements, but rather form conventional load switches by means of the MOSFET switches 52 of these elements, and these load switches can be switched to their conducting states that connect the voltage source 12 to the load 14 by correspondingly controlling their gate terminals 36. As shown in FIG. 1, since all MOSFET cutoff switch elements 24, 26, 28, 30 that are not configured as current monitoring cutoff switch elements are commonly under the control of the control unit 40, these elements can be switched between their conducting states and their open states together, that is, by the transmission of just one control signal.

[0029] An important difference between the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element and generally called an IPS (Intelligent Power Switch), and the MOSFET cutoff switch elements 24, 26, 28, 30 that operate as load switches and are not configured as current monitoring cutoff switch elements, is that the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element has a relatively high resistance in the conducting state and has an electrical resistance in the mΩ range, whereas the MOSFET cutoff switch elements 24, 26, 28, 30 that are not configured as current monitoring cutoff switch elements have a low resistance in the conducting state and have an electrical resistance in the μΩ range. A further important difference is that the maximum allowable current for the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element is in the range of up to 100 - 150 A at most, whereas currents in the hundreds of amperes can be guided through the MOSFET cutoff switch elements 24, 26, 28, 30 that operate as load switches and are not configured as current monitoring cutoff switch elements, respectively.

[0030] Since the resistances in the conducting state are different, if a current of several 100 A, for example, up to 600 A, is to flow between the voltage source 12 and the load 14, most of this current flows through the MOSFET cutoff switch elements 24, 26, 28, 30 that are connected in parallel to each other and are not configured as current monitoring cutoff switch elements, while only a significantly smaller current flows through the MOSFET cutoff switch element 22 that is connected in parallel to the MOSFET cutoff switch elements 24, 26, 28, 30 and is configured as a current monitoring cutoff switch element. Contributing to this is the fact that the low-resistance MOSFET cutoff switch elements 24, 26, 28, 30 that are not configured as current monitoring cutoff switch elements are connected in parallel, so that the total electrical resistance formed by these elements is 5% to 15% of the resistance formed by the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element.

[0031] Since the ratios of the various electrical resistances are known, basically, by supplying a current amount corresponding only to the current flowing through the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element, the current flowing through the entire cutoff switch device 16 can be estimated. Therefore, considering the various electrical resistances of the various MOSFET cutoff switch elements 22, 24, 26, 28, 30 and considering the situation where substantially the same voltage is applied to all the MOSFET cutoff switch elements 22, 24, 26, 28, 30, the total current flowing between the voltage source 12 and the load 14 is estimated by using the current amount.

[0032] In the manufacture of this type of semiconductor device, due to manufacturing tolerances, there may also be at least a slight deviation in electrical resistance. Therefore, in this case, it is advantageous to determine the electrical resistance of the MOSFET cutoff switch elements 22, 24, 26, 28, 30 or their MOSFET switches 50, 52 used in the cutoff switch device 16 during the calibration process, and then, taking into account the electrical resistance thus determined, provide a calculation criterion used to determine the total current flowing through the cutoff switch device 16 based on the current amount that reproduces the current flowing through the MOSFET cutoff switch element 22.

[0033] For the accurate detection of this current, it is further advantageous or necessary to ensure that substantially equal temperature conditions occur in the various MOSFET cutoff switch elements 22, 24, 26, 28, 30, and that these elements are not heated at different intensities, and thus do not have different temperatures, taking into account the individual resistance values of the various MOSFET cutoff switch elements 22, 24, 26, 28, 30 used in the cutoff switch device 16 so that the current flowing through the cutoff switch device 16 can be accurately identified while considering the current amount. To achieve this, it is advantageous to position all the MOSFET cutoff switch elements 22, 24, 26, 28, 30, for example, by their drain terminals, i.e., their voltage source terminals 32, which each form one main terminal, on a bus bar 54 made of, for example, a copper material and forming a relatively solid part of the voltage source connection region 18. The bus bar 54 not only electrically connects the voltage source terminals 32 of the various MOSFET cutoff switch elements 22, 24, 26, 28, 30 to each other, but also connects these voltage source terminals 32 or their MOSFET switches 50, 52 to conduct heat to each other. Thus, temperature compensation between them can be performed, ensuring that they are at substantially the same temperature level. Alternatively or additionally, the load connection region 20 of the cutoff switch device 16 may be configured using a bus bar 56 of this type made of, for example, a copper material.

[0034] According to the disconnection switch device 16 configured according to the present invention or the in-vehicle voltage network 10 having this device, the following can be considered. That is, when electrical energy is always supplied from the voltage source 12 to the load 14, information regarding the current flowing between the voltage source 12 and the load can be used, and when the disconnection switch device 16 should be switched to a state in which the voltage source 12 is connected to the load 14, at least the MOSFET disconnection switch element 22 configured as a current monitoring disconnection switch element can be considered to be switched to its conducting state, that is, a state in which the voltage source 12 is connected to the load 14.

[0035] If the vehicle or the in-vehicle voltage network 10 is in a low load state where only a relatively small current is expected due to, for example, a low load or load demand in the parking state of the vehicle, it can be considered sufficient to switch only the MOSFET disconnection switch element 22 configured as a current monitoring disconnection switch element to its conducting state. During this time, the MOSFET disconnection switch elements 24, 26, 28, 30 operating as load switches are left in their open states that disconnect the voltage source 12 from the load 14, or are switched to their open states. If this is done, the entire current flowing between the voltage source 12 and the load 14 is guided through the MOSFET disconnection switch element 22 configured as a current monitoring disconnection switch element. Therefore, in this case, the current amount also represents the entire current actually flowing through the disconnection switch device 16. Thus, even in such a low load state, it is guaranteed that accurate current detection can be performed based on a sufficiently large current through the MOSFET disconnection switch element 22.

[0036] Starting from such a low-load state, if, for example, the flow of current increases due to the switching-on of additional electrical energy-consuming devices at load 14, this could lead to a situation where the current flowing between voltage source 12 and load 14 exceeds the maximum current allowed for the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element. This can be identified, for example, by the fact that the current flowing between voltage source 12 and load 14 exceeds a threshold current, or by the fact that the current gradient, i.e., the change in current over time, is of such a magnitude as to exceed an assigned threshold current gradient. That is, using this type of threshold current or threshold current gradient, for example, if at least one of these thresholds is reached or exceeded, the state in which the entire current is guided through the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element can be ended. This also applies to the MOSFET cutoff switch elements 24, 26, 28, 30 not configured as current monitoring cutoff switch elements, which are similarly switched to their conducting states connecting voltage source 12 to load 14. Thus, an overload of the MOSFET cutoff switch element 22 configured as a current monitoring cutoff switch element can be avoided.

[0037] What the structure according to the present invention of the cutoff switch device for a vehicle or the in-vehicle voltage network having this cutoff switch device enables is to reliably provide information regarding the current flowing between the voltage source and the load in the in-vehicle voltage network with a simply constructed structure by using a conventional MOSFET cutoff switch element or by combining at least one MOSFET cutoff switch element configured as a current monitoring cutoff switch element with at least one MOSFET cutoff switch element not configured as a current monitoring cutoff switch element. Depending on the load requirements in the in-vehicle voltage system, various MOSFET cutoff switch elements can be selectively switched to the conductive state or the non-conductive state, so that even in a state where only a relatively small current is flowing between the voltage source and the load, this current can be detected with certainty and good dynamics, provided that, nevertheless, it is possible to avoid an overload of the MOSFET cutoff switch element configured as a current monitoring cutoff switch element, and this is possible even if this MOSFET cutoff switch element can only guide a relatively small proportion of the total current flowing between the voltage source and the load due to its structural form. Thus, it is possible to operate the cutoff switch device with high measurement dynamics over a wide measurement range for the current flowing as a whole, generating only a small power loss and a small inherent current consumption within the range of several 100 μA. Since commercially available semiconductor components can be used for the structure of the cutoff switch device, it is also possible to provide a cutoff switch device with a structure that operates basically reliably without incurring costs.

Claims

1. A cut-off switch device for an in-vehicle voltage network of a vehicle for selectively connecting a voltage source (12) to a load (14) and disconnecting the voltage source (12) from the load (14), the cut-off switch device comprising: a voltage source connection region (18) and a load connection region (20), and a plurality of MOSFET cut-off switch elements (22, 24, 26, 28, 30) connected in parallel with each other between the voltage source connection region (18) and the load connection region (20); at least one of the plurality of MOSFET cut-off switch elements (22, 24, 26, 28, 30), i.e., the MOSFET cut-off switch element (22), is configured as a current monitoring cut-off switch element for supplying a current amount representing a current flowing between the voltage source connection region (18) and the load connection region (20); at least one of the plurality of MOSFET cut-off switch elements (22, 24, 26, 28, 30), i.e., the MOSFET cut-off switch elements (24, 26, 28, 30), is not configured as a current monitoring cut-off switch element; each of the MOSFET cut-off switch elements (22, 24, 26, 28, 30) has a voltage source terminal (32) connected to the voltage source connection region (18), a load terminal (34) connected to the load connection region (20), and a gate terminal (36) connected to a control unit (40); in the conducting state of the at least one MOSFET cut-off switch element (22) configured as a current monitoring cut-off switch element, which connects the voltage source (12) to the load (14), a current monitoring cut-off switch element resistance exists between the voltage source terminal (32) of the at least one MOSFET cut-off switch element (22) configured as a current monitoring cut-off switch element and the load terminal (34) of the at least one MOSFET cut-off switch element (22) configured as a current monitoring cut-off switch element; The at least one MOSFET cutoff switch element (24, 26, 28, 30) not configured as a current monitoring cutoff switch element connects the voltage source (12) to the load (14). In the conducting state of the at least one MOSFET cutoff switch element (24, 26, 28, 30) not configured as a current monitoring cutoff switch element, between the voltage source terminal (32) of the at least one MOSFET cutoff switch element (24, 26, 28, 30) not configured as a current monitoring cutoff switch element and the load terminal (34) of the at least one MOSFET cutoff switch element (24, 26, 28, 30) not configured as a current monitoring cutoff switch element, there is a MOSFET cutoff switch element resistance, The current monitoring cutoff switch element resistance is greater than the MOSFET cutoff switch element resistance, Cutoff switch device.

2. The voltage source terminal (32) is a drain terminal, and the load terminal (34) is a source terminal, The cutoff switch device according to claim 1.

3. The ratio of the total MOSFET cutoff switch element resistance formed by all the MOSFET cutoff switch elements (24, 26, 28, 30) not configured as current monitoring cutoff switch elements to the total current monitoring cutoff switch element resistance formed by all the MOSFET cutoff switch elements (22) configured as current monitoring cutoff switch elements is within the range of 0.05 to 0.15, The cutoff switch device according to claim 1.

4. The at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element includes an overcurrent protection circuit (42). The overcurrent protection circuit (42) is configured to switch the at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element to a state of disconnecting the voltage source (12) from the load (14) or to maintain the state if the current between the voltage source terminal (32) and the load terminal (34) of the at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element exceeds a threshold current. The cutoff switch device according to claim 1.

5. The at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element includes an overheat protection circuit (44), and the overheat protection circuit (44) is configured to switch the at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element to a state of disconnecting the voltage source (12) from the load (14) or to maintain the state if the temperature of the at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element exceeds a threshold temperature. The cutoff switch device according to claim 1.

6. The at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element can be switched between a state of connecting the voltage source to the load and a state of disconnecting the voltage source from the load without depending on at least one MOSFET cutoff switch element (24, 26, 28, 30) not configured as a current monitoring cutoff switch element. The cutoff switch device according to claim 1.

7. The at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element can be switched between a state of connecting the voltage source to the load and a state of disconnecting the voltage source from the load without depending on any MOSFET cutoff switch element (24, 26, 28, 30) not configured as a current monitoring cutoff switch element. The cutoff switch device according to claim 6.

8. The voltage source connection region (18) includes a bus bar (54) electrically connected and thermally conductive to all MOSFET cutoff switch elements (22, 24, 26, 28, 30), and / or The load connection region (20) includes a bus bar (56) electrically connected and thermally conductive to all MOSFET cutoff switch elements (22, 24, 26, 28, 30). The cutoff switch device according to claim 1.

9. The voltage source connection region (18) includes a bus bar (54) electrically connected and thermally conductive to all MOSFET cutoff switch elements (22, 24, 26, 28, 30) and configured as a copper bus bar, and / or The load connection area (20) is conductively connected to all the MOSFET cutoff switch elements (22, 24, 26, 28, 30) and connected so as to conduct heat, and includes a bus bar (56) configured as a copper bus bar. The cutoff switch device according to claim 8.

10. A cutoff switch device for an in-vehicle voltage network of a vehicle for selectively connecting a voltage source (12) to a load (14) and disconnecting the voltage source (12) from the load (14), the cutoff switch device comprising: a voltage source connection area (18) and a load connection area (20), and a plurality of MOSFET cutoff switch elements (22, 24, 26, 28, 30) connected in parallel with each other between the voltage source connection area (18) and the load connection area (20). At least one of the plurality of MOSFET cutoff switch elements (22, 24, 26, 28, 30), i.e., the MOSFET cutoff switch element (22), is configured as a current monitoring cutoff switch element that supplies a current amount representing the current flowing between the voltage source connection area (18) and the load connection area (20). At least one of the plurality of MOSFET cutoff switch elements (22, 24, 26, 28, 30), i.e., the MOSFET cutoff switch elements (24, 26, 28, 30), is not configured as a current monitoring cutoff switch element. Each of the MOSFET cutoff switch elements (22, 24, 26, 28, 30) has a voltage source terminal (32) connected to the voltage source connection area (18), a load terminal (34) connected to the load connection area (20), and a gate terminal (36) connected to a control unit (40). The at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element includes an overcurrent protection circuit (42), and the overcurrent protection circuit (42) is configured such that if the current between the voltage source terminal (32) and the load terminal (34) of the at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element exceeds a threshold current, the at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element is switched to a state of disconnecting the voltage source (12) from the load (14) or held in the state. Cutoff switch device.

11. A cut-off switch device for an in-vehicle voltage network of a vehicle for selectively connecting a voltage source (12) to a load (14) and disconnecting the voltage source (12) from the load (14), wherein the cut-off switch device comprises: a voltage source connection region (18) and a load connection region (20), and a plurality of MOSFET cut-off switch elements (22, 24, 26, 28, 30) connected in parallel with each other between the voltage source connection region (18) and the load connection region (20); at least one MOSFET cut-off switch element (22) of the plurality of MOSFET cut-off switch elements (22, 24, 26, 28, 30) is configured as a current monitoring cut-off switch element that supplies a current amount representing a current flowing between the voltage source connection region (18) and the load connection region (20); at least one MOSFET cut-off switch element (24, 26, 28, 30) of the plurality of MOSFET cut-off switch elements (22, 24, 26, 28, 30) is not configured as a current monitoring cut-off switch element; the at least one MOSFET cut-off switch element (22) configured as a current monitoring cut-off switch element includes an overheat protection circuit (44), and the overheat protection circuit (44) is configured to switch the at least one MOSFET cut-off switch element (22) configured as a current monitoring cut-off switch element to a state of disconnecting the voltage source (12) from the load (14) or to maintain the state if the temperature of the at least one MOSFET cut-off switch element (22) configured as a current monitoring cut-off switch element exceeds a threshold temperature; Cut-off switch device.

12. A cut-off switch device for an in-vehicle voltage network of a vehicle for selectively connecting a voltage source (12) to a load (14) and disconnecting the voltage source (12) from the load (14), wherein the cut-off switch device comprises: a voltage source connection region (18) and a load connection region (20), and a plurality of MOSFET cut-off switch elements (22, 24, 26, 28, 30) connected in parallel with each other between the voltage source connection region (18) and the load connection region (20); At least one of the plurality of MOSFET cutoff switch elements (22, 24, 26, 28, 30), i.e., the MOSFET cutoff switch element (22), is configured as a current monitoring cutoff switch element that supplies a current amount representing the current flowing between the voltage source connection region (18) and the load connection region (20). At least one of the plurality of MOSFET cutoff switch elements (22, 24, 26, 28, 30), i.e., the MOSFET cutoff switch elements (24, 26, 28, 30), is not configured as a current monitoring cutoff switch element. The at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element can switch between a state of connecting the voltage source to the load and a state of disconnecting the voltage source from the load without depending on at least one MOSFET cutoff switch element (24, 26, 28, 30) that is not configured as a current monitoring cutoff switch element. Cutoff switch device.

13. The at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element can switch between a state of connecting the voltage source to the load and a state of disconnecting the voltage source from the load without depending on any MOSFET cutoff switch element (24, 26, 28, 30) that is not configured as a current monitoring cutoff switch element. The cutoff switch device according to claim 12.

14. A cutoff switch device for an in-vehicle voltage network of a vehicle for selectively connecting a voltage source (12) to a load (14) and disconnecting the voltage source (12) from the load (14), the cutoff switch device comprising: a voltage source connection region (18) and a load connection region (20), and a plurality of MOSFET cutoff switch elements (22, 24, 26, 28, 30) connected in parallel to each other between the voltage source connection region (18) and the load connection region (20). At least one of the plurality of MOSFET cutoff switch elements (22, 24, 26, 28, 30), i.e., the MOSFET cutoff switch element (22), is configured as a current monitoring cutoff switch element that supplies a current amount representing the current flowing between the voltage source connection region (18) and the load connection region (20). At least one of the plurality of MOSFET cutoff switch elements (22, 24, 26, 28, 30) is not configured as a current monitoring cutoff switch element, The voltage source connection region (18) includes a bus bar (54) that is conductively connected to and thermally conductive to all of the MOSFET cutoff switch elements (22, 24, 26, 28, 30), and / or, The load connection region (20) includes a bus bar (56) that is conductively connected to and thermally conductive to all of the MOSFET cutoff switch elements (22, 24, 26, 28, 30), Cutoff switch device.

15. Only one MOSFET cutoff switch element (22) is configured as a current monitoring cutoff switch element, and / or a plurality of MOSFET cutoff switch elements (24, 26, 28, 30) are not configured as current monitoring cutoff switch elements, The cutoff switch device according to any one of claims 1, 10, 11, 12, 14.

16. All MOSFET cutoff switch elements (24, 26, 28, 30) that are not configured as current monitoring cutoff switch elements can be switched together between a state of connecting the voltage source (12) to the load (14) and a state of disconnecting the voltage source (12) from the load (14), The cutoff switch device according to any one of claims 1, 10, 11, 12, 14.

17. An in-vehicle voltage network for a vehicle, The in-vehicle voltage network includes a voltage source (12) and a load (14) to which electrical energy is to be supplied from the voltage source (12), The in-vehicle voltage network further includes the cutoff switch device (16) according to any one of claims 1, 10, 11, 12, 14, The voltage source connection region (18) of the cutoff switch device (16) is connected to the voltage source (12), and the load connection region (20) is connected to the load (14), In-vehicle voltage network.

18. A method for operating the in-vehicle voltage network according to claim 17, According to the method, in the low-load operation state of the in-vehicle voltage network (10), at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element is switched to a state of connecting the voltage source (12) to the load (14), and at least one MOSFET cutoff switch element (24, 26, 28, 30) not configured as a current monitoring cutoff switch element is switched to a state of disconnecting the voltage source (12) from the load (14). Method.

19. In the low-load operation state, any MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element is switched to a state of connecting the voltage source (12) to the load (14), and / or any MOSFET cutoff switch element (24, 26, 28, 30) not configured as a current monitoring cutoff switch element is switched to a state of disconnecting the voltage source (12) from the load (14). The method according to claim 18.

20. In the low-load operation state, when all MOSFET cutoff switch elements (24, 26, 28, 30) not configured as current monitoring cutoff switch elements are switched to a state of disconnecting the voltage source (12) from the load (14), if the amount of current supplied by the at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element represents a current exceeding the threshold current, and / or if it represents a change in current over time exceeding the threshold current gradient, at least a part of the MOSFET cutoff switch elements (24, 26, 28, 30) not configured as current monitoring cutoff switch elements is switched to a state of connecting the voltage source (12) to the load (14). The method according to claim 18.

21. In the low-load operation state, when all MOSFET cutoff switch elements (24, 26, 28, 30) not configured as current monitoring cutoff switch elements are switched to a state of disconnecting the voltage source (12) from the load (14), if the amount of current supplied by the at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element represents a current exceeding the threshold current, and / or if it represents a change in current over time exceeding the threshold current gradient, All of the MOSFET cutoff switch elements (24, 26, 28, 30) not configured as current monitoring cutoff switch elements are switched to a state in which the voltage source (12) is connected to the load (14). The method according to claim 20.

22. When the cutoff switch device (16) is to connect the voltage source (12) to the load (14), at least the at least one MOSFET cutoff switch element (22) configured as a current monitoring cutoff switch element is switched to a state in which the voltage source (12) is connected to the load (14). The method according to claim 18.

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