Arrangement for maintaining a functional state in a functional unit of a vehicle

Description

[0001] The present invention relates to an arrangement for maintaining a functional state in a functional unit of a vehicle. Furthermore, the invention relates to such a functional unit and a method.

[0002] It is known from the prior art that functional units such as sensor devices are used in vehicles to provide a specific function for a component of the vehicle. The component is, for example, a door handle, where the sensor device detects the approach of a user. The sensor device is also connected to a control unit of the vehicle for communication, e.g., a result of the detection or the like. To supply such a functional unit with power, a supply voltage is provided for the functional unit via the control unit, for example, via the vehicle's electrical system.

[0003] However, the problem can arise that the power supply is not uninterrupted. Therefore, recurring, short-term voltage drops can impair the adequate power supply and thus the function of the functional unit. These interruptions can be scheduled regularly, meaning they occur constantly and repeatedly, even in fault-free conditions.

[0004] DE 199 29 177 C1 describes a reset circuit for an electronic unit, such as those used in motor vehicles. US 2010 / 253141 A1 deals with voltage drops in the context of capacitive proximity sensors for motor vehicles.

[0005] It is therefore an object of the present invention to at least partially remedy the disadvantages described above. In particular, the object of the present invention is to enable improved operation of a functional unit.

[0006] The above object is achieved by an arrangement having the features of the independent device claim, a functional unit having the features of the further independent device claim, and by a method having the features of the independent method claim. Further features and details of the invention emerge from the respective subclaims, the description, and the drawings. Features and details described in connection with the arrangement according to the invention naturally also apply in connection with the functional unit according to the invention and the method according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reciprocal reference is or can always be made.

[0007] The object is achieved in particular by an arrangement, in particular an electronic circuit arrangement, for maintaining a functional state in a functional unit of a vehicle.

[0008] The functional unit is designed as an electronic unit for a vehicle component, such as a door handle of the vehicle. The functional unit can be integrated into the vehicle component to provide a function for the vehicle component. Such a function includes detecting an activation action, such as detecting an approach and / or gesture. According to the invention, the electronic unit is designed as a capacitive sensor device for detecting an activation action.

[0009] It is also advantageous if the vehicle is designed as a motor vehicle, in particular as a hybrid vehicle or as an electric vehicle, preferably with a high-voltage electrical system and / or an electric motor. Furthermore, it may be possible for the vehicle to be designed as a fuel cell vehicle and / or passenger vehicle and / or a semi-autonomous or autonomous vehicle. Advantageously, the vehicle has a security system that enables authentication, for example, through communication with an identification transmitter (ID transmitter). Depending on the communication and / or authentication, at least one vehicle function of the vehicle can be activated. If authentication of the ID transmitter is necessary for this purpose, this vehicle function can be a safety-relevant function, such as unlocking the vehicle or authorizing an engine start.Thus, the security system can also be designed as a passive access system, which initiates authentication and / or activation of the vehicle function upon detection of the ID transmitter approaching the vehicle without active manual operation of the ID transmitter. For this purpose, for example, a wake-up signal is repeatedly sent by the security system, which can be received by the ID transmitter upon approach, and then triggers authentication. The vehicle function can also involve activating vehicle lighting and / or operating (opening and / or closing) a flap (e.g., front, rear, or side flap or door).

[0010] For example, upon detection of an activation action, in particular the approach of a user with the ID transmitter, the sensor device automatically activates the vehicle lighting and / or upon detection of an activation action in the form of a user gesture, the lid is actuated. For this purpose, the sensor device (or several such sensor devices) can be integrated, for example, in a door handle and / or in a bumper and / or in another vehicle component.

[0011] According to the invention, the sensor device is designed as a capacitive sensor device in order to detect the activation action, in particular approach and / or the gesture and / or the like. For this purpose, the sensor device can have at least one sensor electrode in order to detect a change in the environment of the sensor electrode. In order to detect a gesture, several sensor electrodes can also be provided if necessary. The sensor electrode can each provide a variable capacitance, which can be changed by the change in the environment of the sensor electrodes. One such change is, for example, the approach of a body part of a user of the vehicle. If the sensor device is integrated into the door handle, the detection of the sensor device serves, for example, to initiate the authentication of the user's identification transmitter (electronic key) in the vehicle. In this case, for example,A reaching into a door handle recess can be detected, so that upon detection, authentication is initially initiated, and upon successful authentication, at least one door of the vehicle is unlocked. If the sensor device is integrated into the bumper, for example, upon detection of the sensor device, authentication can initially be initiated, and upon successful authentication, at least one lid, in particular the tailgate, of the vehicle can be unlocked and / or automatically moved into an open position.

[0012] The functional state advantageously relates to a state of the functional unit in which at least one functionality is active and / or a condition (prerequisite) for providing at least one function of the functional unit is met. This functionality can, for example, comprise intermediate storage of data, wherein the stored data can be the prerequisite for a function (such as detection) by the functional unit. In other words, in this case the stored data are the prerequisite for the function being available. However, an interruption, i.e. even a brief voltage drop, in the power supply for the functional unit can conventionally result in the functional state and thus this functionality no longer being guaranteed, with the function being impaired. The power supply is therefore then no longer sufficient to provide the functional state.

[0013] Furthermore, it is provided that an arrangement according to the invention comprises the following components, which can be arranged, for example, on a common printed circuit board and / or interconnected: a (particularly electronic) processing device, such as a microcontroller and / or a processor and / or an integrated circuit and / or an electronic arrangement and / or the like, for at least partially providing the functional state when a power supply of the processing device (iealso energy supply for the functional unit) is sufficient, a supply connection for providing an electrical main energy supply in order to (in particular by the main energy supply) provide the energy supply primarily and / or sufficiently for a first period of time, a storage arrangement for providing an electrical emergency energy supply in order to (in particular by the emergency energy supply) provide the energy supply secondarily and / or sufficiently for a second period of time (in particular for a defined minimum period of time), wherein preferably the minimum period of time is specific for an interruption of the main energy supply, e.g.is adapted to a predefined regular interruption period, and / or the second period is (much) shorter than the first period, a monitoring arrangement for monitoring a parameter specific to the energy supply, in particular a supply voltage of the main energy supply, and initiating an energy-saving mode of the processing device depending on the monitoring (in particular if the interruption of the main energy supply is detected by the monitoring) in order to operate the processing device in the energy-saving mode during the provision of the emergency energy supply. .

[0014] The main power supply can, for example, comprise an electrical power supply provided by an on-board electrical system and / or a rechargeable battery of the vehicle. To provide the main power supply to the functional unit, in particular the processing device, the supply connection can be connected to a supply line of a control unit of the vehicle. The control unit provides the main power supply for the supply connection, for example, by transmitting a supply voltage from the on-board electrical system to the supply line.

[0015] Within the scope of the invention, the term "connection" and in particular "supply connection" can, in a broader sense, refer to any (arbitrary) point of an electrical conductor of the arrangement according to the invention, e.g., a conductor track that is electrically connected to a supply arrangement and / or a voltage regulator and / or the processing device. For example, to provide the primary power supply, the supply connection is electrically connected to the voltage regulator in order to stabilize the supply voltage by the voltage regulator and make it available to the processing device as a stabilized supply voltage. In a narrower sense, the "connection" and in particular "supply connection" can also be embodied as a mechanical connection, such as a plug connection or an electrical contact or the like.

[0016] Primary provision refers in particular to a power supply that is provided primarily and / or continuously – i.e., regularly during the operation of the functional unit. Secondary provision may be provided less frequently, in particular only irregularly and / or briefly and / or in exceptional cases. This refers to a power supply that is provided only exceptionally ("in an emergency"). In particular, the main power supply is permanent because it is supplied by the vehicle's electrical system or a rechargeable battery. In contrast, in the emergency power supply, this supply from the vehicle's electrical system or the rechargeable battery cannot be provided.

[0017] The parameter can be monitored directly, for example, by monitoring the power supply to the processing device, for example, based on the stabilized supply voltage. However, monitoring preferably takes place at the main power supply, for example, at the supply voltage (not stabilized by the voltage regulator) at the supply connection. The supply connection serves, in particular, as an electrical connection to a supply line that can provide the power supply (possibly via the control unit) from the vehicle's electrical system.

[0018] The minimum time period for providing the secondary power supply is, for example, specific to the interruption of the main power supply in that the minimum time period is determined depending on the interruption of the main power supply, in particular on the (known) maximum duration of this interruption. The interruption can be a regular (known) interruption of the main power supply, so that the maximum duration of this interruption is known. It is possible, for example, that due to the way the control unit works, such interruptions occur repeatedly, but never for longer than the maximum duration. In this case, these are not exceptional, unexpected disruptions to the power supply, but rather a predetermined behavior of the main power supply. It may therefore be necessary to take these interruptions into account permanently during the operation of the functional unit.The minimum duration (of the emergency power supply) can therefore be set so that it always corresponds at least to the maximum duration (of the interruption). For this purpose, the storage arrangement can be designed to provide sufficient secondary power supply at least for the minimum duration. "Sufficient" can refer to the fact that the functional state can be maintained. However, functions of the processing device may then be deactivated or no longer available. Accordingly, the processing device may be in a power-saving mode as long as the power supply is only sufficiently provided secondarily. The full functionality of the functional unit may therefore no longer be available during the emergency power supply.However, full functionality can be restored more quickly after the main power supply is restored because the functional status was maintained during the emergency power supply.

[0019] A solution according to the invention therefore has the advantage that the functional state can be maintained in different power supply situations. Monitoring can be used to detect these situations and, based on them, initiate the energy-saving mode. It is conceivable that the energy-saving mode leads to a reduction in the energy consumption of the processing device. This can be useful during the provision of the emergency power supply in order to increase the (second) period during which the emergency power supply can provide sufficient power.

[0020] In this case, it may be possible for the memory arrangement to be designed to provide a sufficient secondary power supply (for the processing device) through the emergency power supply only for a limited period of time, in particular when the main power supply is interrupted. This limited period of time can depend on the energy consumption of the processing device, wherein this energy consumption can be reduced in energy-saving mode in order to increase the period of time or to provide a sufficient power supply at least until the interrupted main power supply is restored. In other words, this period of time can be influenced by the initiation of the energy-saving mode. In this case, the period of time is preferably influenced or increased in such a way that the secondary provision of a sufficient power supply is possible at least until the interrupted main power supply is restored.In other words, energy consumption in energy-saving mode can be reduced in order to increase the time required for the (secondary) provision of sufficient energy, at least until the interrupted main energy supply is restored. This has the advantage that the emergency energy supply can bridge the period of the interruption of the main energy supply until the main energy supply can again take over the energy supply of the processing device. It can be predefined that the main energy supply is normally interrupted for a maximum period of time. In this case, the minimum bridging period must correspond at least to the maximum period. Since the memory arrangement can be designed in such a way that this is not possible during normal operation of the processing device, energy-saving mode can be initiated to achieve this minimum period. This has the further advantage that, if necessary,a capacitance of at least one capacitor of the storage arrangement can be reduced, and yet the energy supply can be provided secondary for a sufficiently long time.

[0021] It may be further advantageous for the monitoring arrangement to further comprise: a comparison unit, such as a comparator or the like, to compare the monitored parameter with a reference and to initiate the energy-saving mode depending on the comparison, optionally: a provision arrangement, in particular in the form of a voltage divider, for providing the parameter to the comparison unit, optionally: a reference unit for providing the reference, The parameter is implemented as a supply voltage of the main power supply. This allows the comparison unit to easily determine when initiation of the power-saving mode is necessary. In other words, the monitoring arrangement can use the comparison unit to monitor the parameter, i.e., to compare it with the reference. Based on the comparison, it can be detected that the main power supply is interrupted, in order to operate the processing device in power-saving mode while the emergency power supply is provided.

[0022] Furthermore, it can be provided that the storage arrangement is electrically connected to the supply connection for charging by the main power supply, in order to automatically provide sufficient power by discharging the storage arrangement secondaryly, in particular only briefly and / or temporarily (to compensate for the interruption), in the event of an interruption of the main power supply by the emergency power supply. For example, the storage arrangement can comprise at least one capacitor which is connected in parallel to the power supply and / or main power supply. This enables the capacitor to be charged via the main power supply, but to provide the emergency power supply in the event of an interruption of the main power supply. This can be possible, for example, in such a way that a voltage drop in the main power supply is compensated for by discharging the at least one capacitor.However, due to the limited capacity of the capacitor, this is only possible for a limited period of time. Initiating power-saving mode allows this period to be extended, at least until the main power supply is restored.

[0023] Within the scope of the invention, an interruption of the main power supply can refer to a state in which the main power supply is insufficient to provide the functional state. For example, the main power supply is then insufficient to provide data storage in the processing device until the main power supply is restored. The main power supply is interrupted, for example, when there is a voltage drop in the main power supply, so that, in particular, the supply voltage falls below a predefined voltage threshold.

[0024] Furthermore, it is optionally provided that the processing device is designed to provide the functional state by temporarily storing data, wherein the data is preferably specific for an evaluation and / or digital filtering, in particular band-pass and / or low-pass filtering, of a detection signal from a capacitive sensor arrangement. The evaluation relates in particular to the detection of an activation action, e.g., by evaluating a detection signal from the sensor arrangement. The digital filtering may be necessary to filter a detection signal from the sensor arrangement. In this way, for example, interference can be reduced. For the evaluation and / or digital filtering, it may also be necessary to temporarily store data for a short period of time.However, if this data is lost during a re-initialization (reset) of the processing device, the evaluation and / or digital filtering functions may not be immediately available again. Re-enabling this function may be time-consuming, which could impair the functionality of the sensor array or functional unit. To avoid this, the emergency power supply can operate the processing device even during an interruption of the main power supply, thus eliminating the need for re-initialization. (Re-initialization occurs automatically, especially if the power supply for the processing device is insufficient.)

[0025] It is further conceivable for the storage arrangement to have at least one capacitor which is electrically coupled to the processing device in order to provide, when charged by the main power supply, the emergency power supply in the event of an interruption in the main power supply, preferably for a minimum period of time which is defined at least by a capacitance of the at least one capacitor and by the energy-saving mode. The capacitance can only be determined to a limited extent because, due to the limited installation space available for the functional unit, capacitors of any size cannot be used. Therefore, a mechanism may be required which nevertheless provides the minimum period of time at a level such that the emergency power supply is regularly always provided at least for the duration of the interruption in the main power supply.Such a mechanism can be provided by initiating the power-saving mode depending on the monitoring. In other words, the power-saving mode can reduce the energy consumption of the processing device and thus also define the minimum time period, namely, increase it.

[0026] Within the scope of the invention, it can optionally be provided that the memory arrangement, in particular the capacity of the memory arrangement, in combination at least with the energy-saving mode, defines the minimum period of time for which the energy supply (i.e., by the emergency energy supply) can be sufficiently provided in the event of an interruption of the main energy supply. The energy-saving mode determines, for example, which functions of the processing device are deactivated in order to reduce the energy consumption of the processing device. These deactivated functions are, for example, communication with the control unit or detection of an approach and / or activation action. Lower energy consumption can result in the limited emergency energy supply being sufficient for longer.

[0027] It can further be provided that the monitoring arrangement is designed to detect, based on the monitoring, a regular interruption of the main power supply with different interruption durations, and that (at least) the storage arrangement and the energy-saving mode are adapted such that the emergency power supply ensures that the secondary power supply is sufficiently provided for at least a maximum duration (i.e., a maximum) of the interruption durations. The regular interruption is, for example, an interruption which, in a fault-free state, can be provided for various reasons (in particular relating to the function of the control unit). The duration of the interruption can vary, so that different interruption durations must be taken into account.This is preferably achieved by designing the storage arrangement and the energy saving mode in such a way that the interruption can be compensated by the emergency power supply at least for the maximum period.

[0028] Advantageously, the invention can provide that the monitoring arrangement is designed to detect a regular interruption of the main power supply based on the monitoring, and that the storage arrangement is designed to provide the secondary power supply sufficiently only for a defined minimum period of time during the interruption, wherein the minimum period is specific to a maximum period of the regular interruption. This can be made possible, for example, by a corresponding design of the capacity of the storage arrangement. The regular interruption is in particular a known, recurring interruption which occurs for operational reasons. The maximum duration of the interruption is therefore known. The emergency power supply can indeed also be provided if an irregular interruption occurs.However, in this case, it cannot be guaranteed that the minimum duration is sufficient to prevent reinitialization of the processing device. If the interruption exceeds the maximum duration, it is not a regular interruption, but rather a malfunction that could lead to a loss of functional status (e.g., data loss). The minimum duration can be specific to the maximum duration of the regular interruption, for example, it can be set so that the emergency power supply is always available for the maximum duration.

[0029] It is further conceivable for the monitoring arrangement to have a comparison unit in the form of a comparator of the processing device in order to monitor the power supply, in particular the main power supply, wherein the comparator is preferably electrically connected to the supply connection via a supply arrangement. The comparison unit can accordingly be part of the processing device, such as a microcontroller, and can thus be integrated into the arrangement in a particularly compact manner. In contrast to alternative comparison units, the comparator often has the advantage of very low power consumption and thus enables very energy-efficient monitoring.

[0030] It may be possible for a supply arrangement of the arrangement according to the invention, in particular in the form of a voltage divider, to be designed to set a supply voltage at the supply connection and / or on the supply line for the comparison unit such that, when the voltage at the comparison unit falls below a predetermined voltage threshold, the supply voltage falls below the reference voltage, in particular the reference voltage. In other words, the supply arrangement makes it possible to set the voltage threshold such that, when the supply voltage falls below the reference voltage, the energy-saving mode is initiated. The supply arrangement can provide a voltage at the comparison unit that is dependent, in particular proportional, to the supply voltage.Preferably, when this voltage at the comparison unit falls below the reference, the supply voltage also falls below the voltage threshold and, as a result, the energy saving mode is initiated.

[0031] Furthermore, it can be advantageous within the scope of the invention for the monitoring arrangement to have a reference unit in the form of a fixed voltage reference of the processing device in order to provide a reference for monitoring, wherein the fixed voltage reference preferably provides the reference in the form of a voltage reference of 1.024 V and / or a multiple thereof. Accordingly, the reference can be fixed and thus unchangeable, in particular predetermined by the processing device. It can also be possible for the reference to be predetermined by the hardware of the processing device. Therefore, it may also be necessary to use the provision arrangement to divide the supply voltage in such a way that the voltage threshold is set as desired.that if the voltage at the comparison unit falls below the reference, the supply voltage falls below the desired voltage threshold.

[0032] The reference unit, particularly in the form of a so-called (internal) fixed voltage reference (FVR), can optionally be permanently integrated into the processing device and / or provide the reference (e.g., in the form of a voltage reference) in a fixed and / or unchangeable and / or preset manner. This has the advantage that the reference unit can be used as a standard component with minimal technical effort. However, this may also require an adjustment of the parameter for the comparison unit.

[0033] It may optionally be possible for the monitoring arrangement to have a comparison unit for comparing a supply voltage of the main power supply with a reference voltage for monitoring purposes, and for initiating the energy-saving mode depending on the comparison. Alternatively or additionally, it may be possible for the monitoring arrangement to have a provision arrangement for adapting the supply voltage to the reference voltage (in particular the reference) and for providing the adapted supply voltage to the comparison unit, so that if the supply voltage falls below a predefined voltage threshold, the provided adapted supply voltage falls below the reference voltage.The voltage threshold can be specific for an interruption of the main power supply, in particular for a minimum operating voltage, and the reference voltage can preferably be non-specific for the interruption of the main power supply, in particular for the minimum operating voltage, and is particularly preferably fixedly predetermined by a reference unit of the processing device. Since the reference (or reference voltage) can be predetermined by the processing device as a component, its definition then does not specifically take into account the interruption of the main power supply or the minimum operating voltage. Thus, it may be necessary to take into account the immutability of the reference by adjusting the supply voltage by means of the supply arrangement. The supply voltage can be understood as the monitored parameter.The minimum operating voltage is specifically defined as a voltage below which, if exceeded, the processing device must be reinitialized. This can be a so-called "brownout" threshold, which the processing device requires at least for operation, such as 2.05 V.

[0034] Furthermore, it is conceivable that the processing device is designed to at least partially provide a function in the form of detecting an activation action on a door handle, in particular by the processing device being in signal communication with at least one sensor arrangement in order to control the sensor arrangement to detect the activation action, to receive a detection signal from the sensor arrangement, and / or to detect the activation action based on an evaluation and / or digital filtering of the detection signal, and / or to transmit information about the detection to a control unit of the vehicle. Communication, such as power line communication via the supply line, can be provided for transmitting the information. However, this communication may be interrupted in energy-saving mode.

[0035] Furthermore, it is provided within the scope of the invention that the monitoring arrangement is designed to carry out the monitoring as detection of a repeatedly occurring, short-term voltage failure of the main power supply in order to initiate the energy-saving mode by switching off at least one function of the processing device upon detection of the voltage failure. Such a function is, for example, the transmission of information to the vehicle's control unit and / or an evaluation of the sensor arrangement and / or a digital filtering of the sensor arrangement. However, the data for the at least one function can, if necessary, remain stored (preserved) in order to be able to provide the function again quickly or immediately after the end of the energy-saving mode and / or after the main power supply is restored.

[0036] Furthermore, it may be advantageous within the scope of the invention that the monitoring arrangement is designed to initiate the energy saving mode as a mode of the processing device in which: the functional state is maintained in that data for a function are stored in a (particularly volatile) data storage unit, so that the data are available again after the end of the energy saving mode, and / or the function is suspended until the energy saving mode is ended, and / or a clock frequency of the processing device, in particular a processor of the processing device, is at least reduced, and / or communication of the functional unit with a control unit of the vehicle is suspended.

[0037] In this case, the clock frequency can at least be reduced, ie the clock can also be stopped, i.e. a clock frequency of 0 / s can be set. This cannot therefore limit the operation of the arrangement according to the invention, since the comparison unit (in particular the comparator) is static and thus independent of the

[0038] The processor of the processing device can be operated. Furthermore, according to the invention, communication with the vehicle's control unit and measured value acquisition by the sensor arrangement (namely in the form of a capacitive sensor) are deactivated in energy-saving mode.

[0039] As soon as the main power supply is sufficiently restored, the comparison unit can advantageously detect that the corresponding voltage threshold has been exceeded, and the original state of the processing device can be restored. This can take advantage of the fact that the data has been retained in a data storage unit, for example, to restore the output during communication to its last state.

[0040] A data storage unit of an arrangement according to the invention can advantageously be provided in the form of an electronic data storage device, in particular a volatile memory and / or RAM memory, in particular integrated into the processing device. This enables rapid and short-term buffering of data necessary for the function of the functional unit, in particular the processing device. However, buffering may only be guaranteed if the power supply is sufficient.

[0041] It is also advantageous if, within the scope of the invention, the storage arrangement is designed to provide the emergency energy supply for a specific maximum duration (i.e. in particular the limited duration), and the monitoring arrangement and / or processing device is designed to to initiate a shutdown and / or restart (re-initialization) of the processing device if the main power supply is still interrupted, otherwise to end the power saving mode when the main power supply is restored.

[0042] During a restart (reset), the data in a data storage unit of the processing device may be lost. A new initialization of the processing device may then be necessary, during which the function cannot be provided. This is particularly related to the loss of historical data stored, for example, for digital filtering.

[0043] Furthermore, within the scope of the invention, the processing device can be designed as a microcontroller. This has the advantage of allowing a particularly compact design.

[0044] The invention also relates to a functional unit for a vehicle, in the form of a capacitive sensor device for a door handle of the vehicle for detecting an activation action, with an arrangement according to the invention for maintaining a functional state.

[0045] The functional unit according to the invention thus brings with it the same advantages as have been described in detail with reference to an arrangement according to the invention.

[0046] The invention also relates to a method for maintaining a functional state in a functional unit of a vehicle. The following steps are preferably performed consecutively in the specified order or in any desired sequence, whereby individual steps can also be repeated and / or at least partially performed in parallel: Providing a functional state when a power supply of a processing device is sufficient, providing a main electrical power supply to provide the primary power supply sufficiently, providing an emergency electrical power supply to provide the secondary power supply sufficiently, monitoring a parameter specific to the power supply, namely a supply voltage of the main power supply, and initiating a power saving mode of the processing device depending on the monitoring in order to operate the processing device in the power saving mode during the provision of the emergency power supply.

[0047] The method according to the invention thus brings with it the same advantages as have been described in detail with reference to an arrangement according to the invention, wherein an arrangement according to the invention and / or a functional unit according to the invention is operated within the scope of the method according to the invention.

[0048] Further advantages, features, and details of the invention will become apparent from the following description, which describes embodiments of the invention in detail with reference to the drawings. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination. They show: Figure 1 shows a schematic side view of a vehicle with a functional unit according to the invention, Figure 2 shows a schematic representation of an arrangement according to the invention, Figure 3 shows a schematic representation of an arrangement according to the invention, Figure 4 shows a schematic representation for visualizing a method according to the invention.

[0049] In the following figures, identical reference numerals are used for the same technical features, even in different embodiments.

[0050] A vehicle 1 with a functional unit 6 according to the invention is shown in Figure 1shown in a side view. Such a functional unit 6 is embodied in the form of at least one electronic unit 6 of a door handle 2 of the vehicle 1. According to the invention, such a functional unit 6 is a capacitive sensor device 6, which can be used in the vehicle 1 to detect an activation action. For this purpose, the sensor device has, for example, at least one sensor electrode 51 to detect an approach to the sensor electrode 51. The approach comprises, for example, reaching into a door handle recess of the door handle 2 in order to open a door of the vehicle 1. The activation action can be this approach, but optionally also a gesture to also trigger a function such as opening in the vehicle 1. In addition to the example shown, i.e. on the door handle 2, the functional unit 6 can also be used in another component of the vehicle 1, e.g., in a bumper.This may make it possible to automatically open a hatch (in particular the tailgate) of the vehicle 1 upon detection of the approach and / or activation action. This detection is particularly part of a function of the functional unit 6 and requires, for example, an evaluation and / or digital filtering of a detection signal in a sensor arrangement 50 of the functional unit 6.

[0051] In order to activate a function on the vehicle upon successful detection, it may be necessary to transmit a detection signal to a control unit 5 of the vehicle 1 upon detection. The detection signal can thus inform the control unit 5 that the approach and / or activation action has been detected. In response, the control unit 5 can activate a function of the vehicle 1, e.g., authentication and / or unlocking.

[0052] Furthermore, the control unit 5 can also provide a power supply for the functional unit 6. For this purpose, the control unit 5 is electrically connected, for example, to an energy storage device of the vehicle 1 (in particular via an on-board electrical system). For the power supply and, if necessary, simultaneously for the transmission of the detection signal, i.e., for communication with the control unit 5, the functional unit 6 can be connected to the control unit 5 via an electrical supply line 7. The supply line 7 can be a single electrical conductor and / or a line with the same potential, such as a stranded wire, in order to provide a supply voltage Ub to the functional unit 6 for the power supply and, if necessary, to carry out the communication simultaneously by changing this supply voltage Ub and / or the associated electrical current.

[0053] An exemplary connection arrangement between the control unit 5 and the functional unit 6 for providing the energy supply explained above is shown in Figure 2The arrangement 10 according to the invention shown here is part of the functional unit 6 and comprises a monitoring arrangement 11 and a processing device 30. The processing device 30 is designed, for example, as a microcontroller or an integrated circuit or an electronic arrangement or the like. It is shown that the control unit 5 transmits a supply voltage Ub via a supply line 7 to a supply connection 60 and additionally provides a ground potential GND for the arrangement 10 according to the invention via a ground line 8. This makes it possible to provide a sufficient energy supply at least for the processing device 30. This energy supply, which is provided by at least one energy storage device of the vehicle 1 and via the control unit 5, can thus serve as the permanent, regular energy supply to the functional unit 6.Such an energy supply is also referred to below as the main energy supply.

[0054] In Figure 31 shows an arrangement 10 according to the invention for maintaining a functional state in a functional unit 6 of a vehicle 1 with further details. The arrangement 10 according to the invention has an electronic processing device 30 for at least partially providing the functional state. However, this provision of the functional state can only be possible if the power supply to the processing device 30 is sufficient. If, however, this power supply is not sufficiently provided for the processing device 30, the functional state can be impaired. The functional state includes, for example, a state in which function-relevant data of the functional unit 6 or the processing device 30 is stored and thus available for a function of the functional unit 6. This data can, for example, be stored and / or used by the processing device 30.However, if the processing device 30 is not supplied with sufficient power, this data may be lost.

[0055] In order to be able to provide sufficient primary energy supply, a main energy supply is provided. This can be provided via a supply connection 60. In other words, the supply connection 60 serves to provide sufficient primary energy supply via the main energy supply.

[0056] However, it is possible that the main power supply cannot continuously and adequately provide the energy supply. Although the main power supply then continues to serve as the primary, i.e., regular or permanent, energy supply, it is not uninterrupted. To maintain the functional state, it may therefore be possible to compensate for these interruptions in the main power supply. For this purpose, a storage arrangement 20 is used to provide an emergency electrical power supply, so that the emergency power supply can adequately provide the secondary energy supply, in particular for a defined minimum period of time. The minimum period of time can be specific to an interruption in the main power supply, e.g., it can be determined taking into account the regularly scheduled interruption.This determination should preferably be made in such a way that the emergency power supply is available for at least the maximum duration of the interruption. This ensures that the functional state is always maintained. To determine the minimum duration, a capacity of the storage arrangement 20 can be adjusted, for example. The capacity defines, for example, the amount of charge available by the storage arrangement 20 for the emergency power supply. If the storage arrangement 20 is a capacitor arrangement 20 with at least one capacitor 21, the capacity thus refers to the capacitance of the capacitor 21.

[0057] However, the resulting increase in the minimum duration may be accompanied by an increase in capacity and thus also by an increase in the technical effort and the necessary installation space.

[0058] An idea underlying the invention may be that the capacity and thus the technical effort and the necessary installation space can be reduced if the energy consumption of the processing device 30 can be reduced for a given necessary minimum time period.

[0059] To enable this, a monitoring arrangement 11 is provided for monitoring a parameter specific to the power supply, namely a supply voltage Ub of the main power supply. To reduce energy consumption, the monitoring arrangement 11 can initiate an energy-saving mode of the processing device 30. This initiation can be carried out depending on the monitoring, in particular if the interruption of the main power supply is detected by the monitoring. The initiation can thus be carried out in such a way that the processing device 30 is operated in energy-saving mode while the emergency power supply is provided.The storage arrangement 20 can be designed to provide sufficient secondary power only for a limited period of time through the emergency power supply when the main power supply is interrupted. This period of time depends on the energy consumption of the processing device 30. This energy consumption is reduced in the energy-saving mode in order to increase the time for providing sufficient power at least until the interrupted main power supply is restored. In other words, by using the energy-saving mode, this limited period of time can be increased to such an extent that it corresponds at least to the minimum period of time.

[0060] In Figure 3It is shown that the capacitor 21 of the storage arrangement 20 is charged by the main power supply in order to provide the secondary power supply via the emergency power supply only for a limited period of time, automatically when the main power supply is interrupted. The main power supply is provided, for example, by a voltage regulator 9 being electrically connected to the supply line 7 (in particular via the supply terminal 60) in order to stabilize the supply voltage Ub and thus provide it in the form of a stabilized voltage supply Uv for the processing device 30.

[0061] To enable detection of the interruption, the monitoring arrangement 11 can have a comparison unit 31 for comparing the monitored parameter with a reference and for initiating the energy-saving mode depending on the comparison. For this purpose, a signal is output at a control output Oc, for example, when the parameter falls below the reference. To ensure that the parameter can be made available to the comparison unit 31, a provision arrangement 40 is provided. This is in the form of a voltage divider, for example, which adjusts the supply voltage Ub via two resistors R and applies it as the adjusted supply voltage Ub' to the comparison unit 31. The adjustment makes it possible to detect a specific voltage drop in the supply voltage Ub and thus the interruption, regardless of the selected reference.This has the advantage that a reference unit 32 can also provide the reference in the form of a reference that is not specific to the voltage drop. This means that a standard reference, such as a fixed voltage reference, can be used to keep the technical complexity to a minimum. The reference for monitoring is designed, for example, as a voltage reference, e.g., at a level of 1.024 V or a multiple thereof. In order to nevertheless detect when the supply voltage Ub falls below a predefined voltage threshold, the provision arrangement 40 can adjust the supply voltage Ub such that when the supply voltage Ub falls below the voltage threshold, the provided adjusted supply voltage Ub' falls below the reference. The voltage threshold can be specific for an interruption of the main power supply, in particular for a minimum operating voltage, preferably for a brown-out threshold.Preferably, the reference, in particular reference voltage, is non-specific for the interruption of the main power supply, and particularly preferably fixedly predetermined by a reference unit 32 of the processing device 30.

[0062] The monitoring arrangement 11 can be designed to initiate the energy-saving mode as a mode of the processing device 30, in which the functional state is maintained by storing data for a function in a data storage unit 33, so that the data are available again after the end of the energy-saving mode. In this case, the function can be suspended in the energy-saving mode until the energy-saving mode is ended. Likewise, a clock frequency of the processing device 30 can at least be reduced, wherein, furthermore, according to the invention, communication between the functional unit 6 and the control unit 5 of the vehicle 1 is suspended when the energy-saving mode is active.

[0063] In Figure 4The method steps of a method according to the invention are shown schematically. According to a first method step 101, a functional state is provided when the power supply of a processing device 30 is sufficient. According to a second method step 102, a main electrical power supply is provided for this purpose in order to provide a sufficient primary power supply. According to a third method step 103, an emergency electrical power supply is provided in order to provide a sufficient secondary power supply.In addition, according to a fourth method step 104, a parameter specific to the energy supply, namely a supply voltage Ub of the main energy supply, is monitored and an energy-saving mode of the processing device 30 is initiated as a function of the monitoring in order to operate the processing device 30 in the energy-saving mode during the provision of the emergency energy supply.

[0064] The above explanation of the embodiments describes the present invention exclusively by way of example. Of course, individual features of the embodiments can be freely combined with one another, provided they are technically feasible, without departing from the scope of the present invention as defined by the independent claims. List of reference symbols

[0065] 1Vehicle 2Door handle 5Control unit 6Functional unit, electronic unit, capacitive sensor device 7Supply line, communication line 8Ground line 9Voltage regulator 10Arrangement, circuit arrangement 11Monitoring arrangement 20Storage arrangement, capacitor arrangement 21Capacitor 30Processing device 31Comparator 32Reference unit, fixed voltage reference 33Data storage unit 40Provision arrangement, voltage divider 50Sensor arrangement 51Sensor electrode 60Supply connection GNDGround OcControl output RResistance Uvstabilized power supply for 30 UbSupply voltage Ub'adapted supply voltage

Claims

1. Arrangement (10) for maintaining a functional state in a functional unit (6) of a vehicle (1), namely in an electronic unit (6) of a door handle (2) of the vehicle (1), namely in a capacitive sensor device (6) of the door handle (2) for detecting an activation action: - an electronic processing device (30) for at least partially providing the functional state when an energy supply to the processing device (30) is sufficient, - a supply connection (60) for providing a electrical main energy supply in order to provide a sufficient primary energy supply, - a storage arrangement (20) for providing an emergency electrical energy supply in order to provide a sufficient secondary energy supply, - a monitoring arrangement (11) for monitoring a parameter specific to the energy supply, namely a supply voltage (Ub) of the main energy supply, and initiating an energy-saving mode of the processing device (30) in dependence on the monitoring, in order to operate the processing device (30) in the energy-saving mode during the provision of the emergency energy supply, characterized in that the monitoring arrangement (11) is designed to carry out the monitoring as detection of a repeatedly occurring, short-term power failure of the main energy supply, in order to initiate the energy-saving mode as a mode of the processing device (30) by switching off at least one function of the processing device (30) when the power failure is detected, in which: - a communication of the functional unit (6) with a control unit (5) of the vehicle (1) is interrupted and measured value acquisition at the sensor device (6) is interrupted.

2. Arrangement (10) according to claim 1, characterized in that the storage arrangement (20) is designed to provide the energy supply sufficiently by means of the emergency energy supply only for a limited period of time in secondary mode when the main energy supply is interrupted, the limited period of time being dependent on the energy consumption of the processing device (30), this energy consumption being reduced in energy-saving mode in order to provide the sufficient energy supply at least until the interrupted main energy supply is restored.

3. Arrangement (10) according to claim 1 or 2, characterized in that the monitoring arrangement (11) further comprises: - a comparison unit (31) to compare the monitored parameter with a reference and to initiate the energy-saving mode depending on the comparison, - a provision arrangement (40), in particular in the form of a voltage divider (40), for providing the parameter to the comparison unit (31), - a reference unit (32) for providing the reference, where the parameter is designed as a supply voltage (Ub) of the main energy supply.

4. Arrangement (10) according to one of the preceding claims, characterized in that the storage arrangement (20) is electrically connected to the supply connection (60) for charging by the main energy supply, in order to automatically provide sufficient energy supply by means of the emergency energy supply in the event of an interruption in the main energy supply by means of a secondary discharge, and / or in that the storage arrangement (20) has at least one capacitor (21) which is electrically coupled to the processing device (30) in order to provide the emergency energy supply, charged by the main energy supply, in the event of an interruption in the main energy supply, preferably for a minimum period of time which is defined at least by a capacitance of the at least one capacitor (21) and by the energy-saving mode.

5. Arrangement (10) according to one of the preceding claims, characterized in that the processing device (30) is designed to provide the functional state by means of intermediate storage of data, the data preferably being specific for an evaluation and / or digital filtering, in particular band-pass and / or low-pass filtering, of a detection signal of a capacitive sensor arrangement (50).

6. Arrangement (10) according to one of the preceding claims, characterized in that the monitoring arrangement (11) is designed to detect a regular interruption of the main energy supply with different interruption durations on the basis of the monitoring, and in that the storage arrangement (20) and the energy-saving mode are adapted in such a way that the emergency energy supply provides the secondary energy supply sufficiently at least for a maximum duration of the interruption durations, and / or in that the monitoring arrangement (11) has a comparator unit (31) in the form of a comparator (31) of the processing device (30) in order to monitor the energy supply, in particular the main energy supply, the comparator (31) preferably being electrically connected to the supply connection (60) for this purpose via a provision arrangement (40) and / or in that the monitoring arrangement (11) comprises a reference unit (32) in the form of a fixed voltage reference of the processing device (30) to provide a reference for the monitoring, preferably the fixed voltage reference providing the reference in the form of a voltage reference in the amount of 1.024 V or a multiple thereof.

7. Arrangement (10) according to one of the preceding claims, characterized in that the monitoring arrangement (11) has a comparison unit (31) in order to compare a supply voltage (Ub) of the main energy supply with a reference voltage for the monitoring, and in order to initiate the energy-saving mode as a function of the comparison, and in that the monitoring arrangement (11) has a provision arrangement (40) in order to adapt the supply voltage (Ub) to the reference voltage, and to provide the adapted supply voltage (Ub') at the reference unit (31), so that when the supply voltage (Ub) falls below a predefined voltage threshold, the adapted supply voltage (Ub') provided falls below the reference voltage, wherein preferably the voltage threshold is specific for an interruption of the main energy supply, in particular for an operating minimum voltage, and preferably the reference voltage is non-specific for the interruption of the main energy supply, particularly preferably is fixedly predetermined by a reference unit (32) of the processing device (30).

8. Arrangement (10) according to one of the preceding claims, characterized in that the processing device (30) is designed to at least partially provide a function in the form of detection of an activation action in a door handle (2), in particular in that the processing device (30) is in signal connection with at least one sensor arrangement (50) in order to - actuate the sensor arrangement (50) for detecting the activation action in order to receive a detection signal from the sensor arrangement (50), and / or - to detect the activation action on the basis of an evaluation and / or digital filtering of the detection signal, and / or - to transmit information about the detection to a control unit (5) of the vehicle.

9. Arrangement (10) according to one of the preceding claims, characterized in that the monitoring arrangement (11) is further adapted to initiate the energy saving mode as a mode of the processing device (30) in which: - the functional state is maintained in that data for a function is stored in a data storage unit (33) so that the data is available again after the energy-saving mode has ended, and / or - the function is suspended until the energy-saving mode is ended, and / or - a clock frequency of the processing device (30) is at least reduced.

10. Arrangement (10) according to one of the preceding claims, characterized in that the storage arrangement (20) is designed to provide the emergency energy supply for a specific maximum duration, and the monitoring arrangement (11) and / or processing device (30) is designed to provide the emergency energy supply after the maximum duration - to initiate a switch-off and / or a restart of the processing device (30) if the main energy supply is still interrupted, - otherwise end the energy-saving mode when the main energy supply is restored.

11. Arrangement (10) according to one of the preceding claims, characterized in that the processing device (30) is designed as a microcontroller.

12. Functional unit (6) for a vehicle (1), in the form of a capacitive sensor device (6) for a door handle (2) of the vehicle (1) for detecting an activation action, having an arrangement (10) for maintaining a functional state characterized in that the arrangement (10) is designed according to one of the preceding claims.

13. Method for maintaining a functional state in a functional unit (6) in the form of a capacitive sensor device (6) for a door handle (2) of a vehicle (1) for detecting an activation action, wherein the following steps are provided: - Providing a functional state when an energy supply of a processing device (30) is sufficient, - Provision of a main electrical energy supply to ensure a sufficient primary energy supply, - Provision of an emergency electrical energy supply to ensure a sufficient secondary energy supply, - Monitoring a parameter specific to the energy supply, namely a supply voltage (Ub) of the main energy supply, and initiating an energy-saving mode of the processing device (30) in dependence on the monitoring to operate the processing device (30) in the energy-saving mode during the provision of the emergency energy supply, wherein an arrangement (10) and / or a functional unit (6) according to one of the preceding claims is operated.