System with self-test capability, method for a self-test, and at least partially electrically driven motor vehicle having the system
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-01-26
- Publication Date
- 2026-08-13
Smart Images
Figure DE2026100087_13082026_PF_FP_ABST
Abstract
Description
2024P01434 Description System with self-test, method for self-testing and at least partially electrically powered motor vehicle that incorporates the system
[0001] The present invention relates to a system comprising a low-voltage domain and a high-voltage domain, wherein the low-voltage domain and the high-voltage domain are galvanically isolated from each other by an isolation barrier.
[0002] Furthermore, the present invention relates to a method for self-testing a function of the above system, and preferably for performing a self-test of a voltage measurement.
[0003] Additionally, the present invention relates to a motor vehicle that is at least partially electrically powered and has the above system.
[0004] Electrical power systems for vehicles are becoming increasingly important with the rise of electrification in the automotive sector. Electric vehicles are typically powered by an electric motor, which draws its energy from a high-voltage battery pack. In the inverter unit, three-phase AC voltage is generated from the DC voltage of the battery pack, which is then used to drive the motor. Depending on the battery pack, the electric vehicle, and the power requirements, the voltage used in the drive and charging components ranges from approximately 200 V to approximately 900 V.
[0005] Although the electric vehicle's drive and charging components operate at high voltage, other electrical components in the vehicle, such as the on-board system, operate at low voltage, such as 12 / 24 V. In the automotive sector, a voltage above 60 V (DC) is generally considered high voltage, as this highlights the fact that, unlike 12 / 24 V, for example, a voltage above 60 V is dangerous for humans if no additional protective measures are in place. 2024P01434
[0006] The different voltage levels used in vehicles must be able to operate separately, independently, and simultaneously. For safety reasons, it is essential to galvanically isolate the high-voltage system(s) from the low-voltage system(s). A high level of protection can be provided, for example, by physically separating the circuits to ensure as little physical contact as possible, which greatly reduces the risk of a short circuit. Additionally, monitoring functions such as voltage measurement tests (including voltage sensing diagnostics) and / or overvoltage detection and testing procedures are required for safety purposes to verify the functionality and reliability of components in the high-voltage environment.
[0007] Typically, the voltage in the high-voltage system is measured by converting it into a digital signal using an analog-to-digital converter (ADC), and its value is monitored by a microcontroller. However, if the microcontroller is located in the low-voltage domain, the sensing path crosses the galvanic isolation barrier between the high-voltage and low-voltage domains.
[0008] Since the detection path crosses the galvanic isolation barrier, it is difficult to implement a self-test for the detection path without increasing the number of components that bridge the isolation barrier.
[0010] Therefore, an object of the invention is to provide means for self-testing components and / or functions in the high-voltage domain of the system. In particular, an object of the invention is to provide means for self-testing without increasing the number of components that bridge the galvanic isolation barrier.
[0011] The object of the invention is at least partially achieved by the features of the independent claims. Modified embodiments are described in detail in the dependent claims.
[0012] Thus, the task is solved by a system that has a low-voltage domain and a high-voltage domain, where the 2024P01434 The low-voltage domain and the high-voltage domain are galvanically isolated from each other by an isolation barrier, the system comprising a sensing path and an ADC (analog-to-digital converter) in the high-voltage domain and a microcontroller in the low-voltage domain, the sensing path being connectable to a high-voltage source to receive an input voltage, the sensing path comprising a voltage divider, the voltage divider being configured to divide the input voltage into an output voltage with a predetermined division ratio, the ADC being configured for voltage measurement to receive the output voltage from the sensing path, convert the output voltage into a digital voltage signal, and transmit the digital voltage signal across the isolation barrier to the microcontroller, including self-testing of the voltage measurement, such as voltage sensing diagnostics and / or overvoltage detection.the ADC is further configured to receive command signals from the microcontroller to control a first general-purpose output of the ADC in the high-voltage domain, and wherein the system in the high-voltage domain has a first additional circuit arrangement, wherein the first additional circuit arrangement is configured to superimpose an additional voltage on the output voltage after receiving a signal from the first general-purpose output of the ADC.
[0013] Furthermore, the problem is also solved by a method for self-testing a function of a system, and preferably for self-testing a voltage measurement, wherein the system is designed as described above, comprising the following steps: Received, by the ADC, a command signal to perform a self-test of a voltage measurement from the microcontroller, After receiving the command signal, the first multi-purpose output of the ADC is controlled so that the first additional circuit arrangement superimposes the additional voltage onto the output voltage of the detection path. Receiving the output voltage of the sensing path by the ADC, sending, from the ADC to the microcontroller, a digital voltage signal based on the received output voltage, and 2024P01434 Verify, via the microcontroller, that the value of the received digital voltage signal is related to the value of the superimposed additional voltage.
[0014] One aspect of the invention is that the ADC is configured to receive command signals from the microcontroller to control the first general-purpose output of the ADC in the high-voltage domain. Furthermore, the system includes a first additional circuit arrangement configured to superimpose the additional voltage onto the output voltage after receiving the signal from the first general-purpose output of the ADC. In other words, by using the ADC bidirectionally—that is, not only to send the digital voltage signal from the ADC to the microcontroller but also to receive command signals from the microcontroller—it is possible to provide a self-test procedure without increasing the number of components that bridge the galvanic isolation barrier. This makes self-tests very cost-effective and space-saving. Specifically, the ADC has the first general-purpose output in the high-voltage domain.The first multi-purpose output can be controlled by means of the command signals that can be received by the microcontroller.
[0015] If the sensing path is connected to the high-voltage source, the system can be used to measure the input voltage. This is because the input voltage is divided by the voltage divider with a predetermined division ratio into the output voltage, which is then received by the ADC, converted into a digital voltage signal, and sent to the microcontroller via the isolation barrier. Thus, the microcontroller can determine the input voltage using the predetermined division ratio and the received digital voltage signal.
[0016] Furthermore, since the system is designed such that the first additional circuit arrangement superimposes the additional voltage onto the output voltage of the sensing path, the microcontroller can also verify the functionality of the sensing path even when the sensing path is not connected to the high-voltage source. When the sensing path is not connected to the high-voltage source, the verification of the 2024P01434 The functionality of the detection path is considered successful if the value of the digital voltage signal corresponds to the superimposed additional voltage.
[0017] In other words, the system and method allow for self-testing of the voltage measurement and thus verification of the functionality of the sensing path without the need to connect the sensing path to the high-voltage source. Therefore, the system and method ensure proper voltage measurement function in terms of accuracy and safety features with a small number of isolation-bridging components, and in particular, without any additional isolation-bridging components for self-testing.
[0018] With reference to the high-voltage and low-voltage domains of the system, and in the context of this application, the voltage level in the high-voltage domain of the system is higher than in the low-voltage domain of the system. Preferably, a voltage equal to or above 60 V (DC) and / or equal to or above 30 V is used. RMS(AC) is considered high voltage. Voltages below these values are preferably considered low voltage.
[0019] Preferably, the system not only includes the voltage measurement functionality implemented by the ADC and the microcontroller, but also overvoltage detection with a self-test function. In this respect, and according to a preferred embodiment of the invention, the system further includes a comparator in the high-voltage domain, wherein the comparator is configured to receive the output voltage from the sensing path as an input signal, and is further configured to send an output signal across the isolation barrier to the microcontroller if the received input signal is equal to or higher than a predetermined threshold.
[0020] In other words, if the detection path is connected to the high-voltage source, the system can detect an overvoltage event because the comparator preferentially generates the output signal if the received input signal is equal to or higher than the predetermined threshold. 2024P01434
[0021] Furthermore, the system preferably also enables self-testing of the overvoltage detection, particularly since the comparator sends the output signal to the microcontroller via the isolation barrier. In this respect, and according to a preferred embodiment of the invention for self-testing the overvoltage detection, the ADC is further configured to receive command signals from the microcontroller to control a second general-purpose output of the ADC in the high-voltage domain, wherein the system in the high-voltage domain has a second additional circuit arrangement, and wherein the second additional circuit arrangement is configured to lower the predetermined threshold of the comparator after receiving a signal from the second general-purpose output of the ADC.
[0022] Thus, the ADC, similar to the self-testing of voltage measurement, is preferably used bidirectionally for the self-testing of overvoltage detection. Preferably, the ADC has a second multi-purpose output in the high-voltage domain, wherein the second multi-purpose output is controllable by command signals that can be received by the microcontroller. Since the system is preferably further configured such that the second additional circuit arrangement can lower the predetermined threshold of the comparator after receiving a signal from the second multi-purpose output of the ADC, it is possible to trigger an overvoltage event, which is then registered by the microcontroller, without the need to connect the detection path to the high-voltage source.
[0023] In connection with this, and according to a further preferred embodiment of the invention, the first additional circuit arrangement and the second additional circuit arrangement are configured such that, when the detection path is not connected to the high-voltage source, and with the superimposed additional voltage, the output voltage of the detection path is higher than the reduced threshold of the comparator. In other words, for self-testing of the overvoltage detection, the first multi-purpose output of the ADC is preferably controlled such that the first additional circuit arrangement superimposes the additional voltage onto the output voltage of the detection path. Furthermore, the second multi-purpose output of the ADC is preferably configured as described in [2024P01434]. controlled so that the second additional circuit arrangement lowers the predetermined threshold of the comparator and thus triggers the overvoltage detection.
[0024] With reference to the method for self-testing a function of a system, and according to a preferred embodiment of the invention, the method preferably comprises the following further steps: Received, by the ADC, a command signal to perform a self-test of an overvoltage detection by the microcontroller, Upon receiving the command signal, an overvoltage detection is triggered by controlling the second multi-purpose output of the ADC, so that the second additional circuit arrangement lowers the predetermined threshold of the comparator, and Verify, via the microcontroller, that the overvoltage detection has been triggered by receiving the comparator's output signal.
[0025] In other words, the system and method preferably allow the overvoltage detection to be tested itself, thus verifying its functionality, without the need to connect the detection path to the high-voltage source. Therefore, the system and method preferably ensure proper overvoltage detection operation with a small number of isolation-bridging components. In particular, the overvoltage detection's self-testing is designed such that no additional isolation-bridging components are required for the self-tests themselves.
[0026] With regard to overvoltage detection, and according to another preferred embodiment of the invention, the system is further configured to send the comparator's output signal to a safety logic to bring the system into a safe state if the received input signal is equal to or higher than a predetermined threshold. Preferably, the safety logic is a fast hardware logic to bring the system into a safe state, preferably by stopping the power transfer, if an overvoltage event occurs. In this context, "fast" preferably means that the system is brought into a safe state by means of the safety logic more quickly than by means of overvoltage event detection by the microcontroller. This can be done. In other words, if the detection path is connected to the high-voltage source, the microcontroller is preferably bypassed for overvoltage detection.
[0027] With regard to the ADC, and according to a preferred embodiment of the invention, the ADC is configured to have bidirectional communication with the microcontroller via a serial peripheral interface. The serial peripheral interface enables bidirectional communication between the ADC and the microcontroller, which allows for self-testing of voltage measurement and / or overvoltage detection. A serial peripheral interface (SPI) is a serial communication bus that follows a master-slave architecture, in which a master device orchestrates communication with one or more subordinate (peripheral) devices by controlling the clock and chip selection signals.
[0028] In connection with this, and according to another preferred embodiment of the invention, a serial peripheral interface bus crosses the isolation barrier by means of digital isolators. The digital isolator enables the transmission of the signal, preferably the digital voltage signal, from the ADC to the microcontroller and the command signal from the microcontroller to the ADC across the isolation barrier, while maintaining electrical isolation between the high-voltage domain and the low-voltage domain. Compared to an optical isolator, the digital isolator has the advantage of being much faster. Additionally, the resulting signal chain—i.e.,, the analog output voltage from the sensing path, which is converted into the digital voltage signal by the ADC and sent to the microcontroller via the isolation barrier using the digital isolator - providing better bandwidth, accuracy and linearity compared to an optocoupler-based system.
[0029] With reference to the ADC and according to another preferred embodiment of the invention, the ADC is configured to send a 12-bit signal. Alternatively or additionally, the ADC is preferably configured to send a signal proportional to the received output voltage from the acquisition path. The 12-bit enables the ADC to read the analog output voltage from the 2024P01434 To convert the acquisition path into the digital voltage signal with a resolution of 4096 discrete digital levels.
[0030] With regard to communication from the microcontroller to the ADC, and according to a further preferred embodiment of the invention, the system is preferably configured such that the command signals from the microcontroller are command signals of a serial peripheral interface. The serial peripheral interface enables a bidirectional communication mode, so that the microcontroller can control the first multi-purpose output of the ADC in the high-voltage domain, and preferably also the second multi-purpose output of the ADC in the high-voltage domain.
[0031] With regard to overvoltage detection, and according to another preferred embodiment of the invention, the system is preferably configured such that the comparator's output signal is transmitted across the isolation barrier by means of a digital isolator. This also ensures that the isolation barrier is maintained even during self-tests or in the event of an overvoltage incident, when the comparator transmits the output signal across the isolation barrier to the microcontroller.
[0032] According to another preferred embodiment of the invention, the first additional circuit arrangement and / or the second additional circuit arrangement preferably utilize an auxiliary power supply in the high-voltage domain. In other words, the first additional circuit arrangement preferably uses the auxiliary power supply to superimpose the additional voltage onto the output voltage, and / or the second additional circuit arrangement uses the auxiliary power supply to lower the predetermined threshold of the comparator. Thus, the self-test functions are implemented using the existing resources already present in the high-voltage domain.
[0033] According to another preferred embodiment of the invention, the ADC is connected to a reference voltage V REFused, which differs from the auxiliary power supply voltage and thus differs from the additional voltage applied by the first circuit arrangement via the output voltage 2024P01434 The voltage measurement is superimposed. Therefore, the self-testing procedure for the voltage measurement can also be used to check the functionality of the auxiliary power supply. If the voltage level of the auxiliary power supply increases or decreases, the microcontroller reads a different value than expected for the superimposed additional voltage.
[0034] The invention also relates to a motor vehicle that is at least partially electrically powered and incorporates the system described above. Due to the cost-effective self-test of the voltage measurement and, preferably, the self-test of the overvoltage detection, which can be implemented without additional insulation-bridging components, the at least partially electrically powered motor vehicle offers increased safety without significantly increasing costs. Furthermore, the space-saving self-test eliminates the need to rearrange other vehicle components when implementing the self-tests.
[0035] According to a preferred embodiment of the invention, a vehicle is provided, wherein the high-voltage source to which the system, and preferably the sensing path, can be connected is the vehicle's battery. Such a vehicle enables the microcontroller to verify that the voltage measurement is functional when the sensing path is not connected to the vehicle's battery. Such a vehicle further preferably enables the microcontroller to verify that the overvoltage detection is functional when the sensing path is not connected to the vehicle's battery.
[0036] These and other aspects of the invention will become clear and are explained with reference to the embodiment described below.
[0037] The following applies to the drawing: Fig. 1 schematically shows a system according to a preferred embodiment of the invention.
[0038] Figure 1 schematically shows a preferred embodiment of a system 10. In this preferred embodiment, the system 10 is installed in an electrically powered 2024P01434 The system is used in a powered vehicle. System 10 comprises a low-voltage domain 12 and a high-voltage domain 14, which are galvanically isolated from each other by an isolation barrier 16. The system includes a microcontroller 18 in the low-voltage domain 12. Figure 1 does not show other potential vehicle components operating in the low-voltage domain, such as the vehicle's on-board system.
[0039] In the high-voltage domain 14, the system includes the sensing path 20 and an analog-to-digital converter, ADC 22. The sensing path 20 can be connected to a high-voltage source 24 for receiving an input voltage. In this preferred embodiment of the invention, the high-voltage source 24 is the vehicle's high-voltage battery.
[0040] As can be seen in Figure 1, the detection path 20 has a voltage divider 26, wherein the voltage divider 26 is configured to divide the input voltage with a predetermined divider ratio into an output voltage.
[0041] For voltage measurement, the system 10 is configured such that the ADC 22 receives the output voltage from the sensing path 20 and converts the output voltage into a digital voltage signal. The digital voltage signal is then sent to the microcontroller 18 via the isolation barrier 16.
[0042] In this preferred embodiment, the system 10 is further configured for overvoltage detection. In this respect, and as can also be seen in Figure 1, the system 10 has a comparator 28 in the high-voltage domain 14. The system 10 is configured such that the comparator 28 receives the output voltage from the detection path 20 as an input signal. The system 10 is further configured such that the comparator 28 sends an output signal across the isolation barrier 16 to the microcontroller 18 if the received input signal is equal to or higher than a predetermined threshold 30.
[0043] In this preferred embodiment, the system 10 is further designed such that the voltage measurement and the overvoltage detection are a2024P01434 The system features self-test functionality. In this respect, for self-testing the voltage measurement, the ADC 22 is configured to receive command signals from the microcontroller 18 to control a first general-purpose output 32 of the ADC 22 in the high-voltage domain 14. Additionally, the system 10 has a first additional circuit arrangement 34 in the high-voltage domain 14. The first additional circuit arrangement 34 is configured to superimpose an additional voltage 36 onto the output voltage after receiving a signal C_1 from the first general-purpose output 32 of the ADC 22.
[0044] For self-testing of the overvoltage detection, the ADC 22 is further configured to receive command signals from the microcontroller 18 to control a second multi-purpose output 38 of the ADC 22 in the high-voltage domain 14. Additionally, the system 10 has a second additional circuit arrangement 40 in the high-voltage domain 14. The second additional circuit arrangement 40 is configured to lower the predetermined threshold value 30 of the comparator 28 after receiving a signal C_2 from the second multi-purpose output 38 of the ADC 22.
[0045] The first additional circuit arrangement 34 and the second additional circuit arrangement 40 are designed such that when the detection path 20 is not connected to the high voltage source 24, and with the superimposed additional voltage 36, the output voltage of the detection path 20 is higher than the reduced threshold 30 of the comparator 28.
[0046] Thus, the system 10 enables the voltage measurement and overvoltage detection to be tested even in a state where the detection path 20 is not connected to the high voltage source 24, using the following procedure:
[0047] To perform a self-test of the voltage measurement, a command signal is received from the microcontroller 18 in the first step of the procedure, prompting the ADC 22 to conduct the self-test. After receiving the command signal, the first general-purpose output 32 of the ADC 22 is controlled such that the first additional circuit arrangement 34 superimposes the additional voltage 36 onto the output voltage of the sensing path 20. Since the sensing path 20 is connected to the ADC 22, the ADC 22 receives the output voltage of the sensing path 20 and transmits 2024P01434 a digital voltage signal proportional to the received output voltage is sent to the microcontroller 18. The microcontroller 18 can verify that the value of the received digital voltage signal corresponds to the value of the superimposed additional voltage 36.
[0048] For self-testing of the overvoltage detection, another command signal is received from the microcontroller 18 to perform the self-test via the ADC 22. After receiving the command signal, the second multi-purpose output 38 of the ADC 22 is controlled to trigger an overvoltage detection, as the second additional circuit arrangement 40 lowers the predetermined threshold 30 of the comparator 28.Since the first additional circuit arrangement 34 superimposes the additional voltage 36 onto the output voltage of the detection path 20, and since the first and second additional circuit arrangements 34, 40 are configured such that, when the detection path 20 is not connected to the high-voltage source 24, and with the superimposed additional voltage 36, the output voltage of the detection path 20 is higher than the reduced threshold 30 of the comparator 28, and the input signal received by the comparator 28 is equal to or higher than its reduced threshold, the overvoltage detection is triggered, and the comparator 28 sends the output signal via the isolation barrier 16 to the microcontroller 18. The microcontroller 18 can then verify that the overvoltage detection has been triggered by receiving the output signal of the comparator 28.
[0049] As can also be seen in Figure 1, in this preferred embodiment of the invention, the ADC 22 is configured to have bidirectional communication with the microcontroller 18 via a serial peripheral interface 42. In particular, a bus of the serial peripheral interface 42 crosses the isolation barrier 16 by means of a digital multi-channel isolator 44, which has several channels with digital isolators 46. In addition, the digital isolators 46 are also used to send the output signal of the comparator 28 across the isolation barrier 16 to the microcontroller 18.
[0050] Furthermore, in this preferred embodiment, the first additional circuit arrangement 34 utilizes an auxiliary power supply (not shown in Figure 1) in the 2024P01434 High-voltage domain 14 is used to superimpose the additional voltage 36 onto the output voltage. Additionally, the ADC 22 is used with a reference voltage 48 that differs from the auxiliary power supply voltage and thus from the additional voltage 36 superimposed on the output voltage by the first circuit arrangement 34. Therefore, the self-testing procedure for the voltage measurement can also be used to check the functionality of the auxiliary power supply. If the voltage level of the auxiliary power supply increases or decreases, the microcontroller 18 reads a different value than expected for the superimposed additional voltage 36.
[0051] Although the invention has been illustrated and described in detail in the drawings and the preceding description, such illustration and description are considered illustrative or exemplary and not limiting; the invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments can be understood and implemented by those skilled in the art in the field who practice the claimed invention by studying the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are cited in mutually distinct dependent claims does not indicate that a combination of these measures cannot be used to advantage.Reference numerals in the claims are not to be interpreted as limiting the scope of protection. 2024P01434. Reference sign 10 System 12 Low-voltage domain 14 High-voltage domain 16 Isolation barrier 18 microcontrollers 20 Recording path 22 Analog-to-Digital Converters (ADCs) 24 High-voltage source, battery 26 voltage dividers 28 Comparator 30 Predetermined threshold of the comparator 32 First multi-purpose output of the ADC 34 first additional circuit arrangement 36 additional voltage 38 Second multi-purpose output of the ADC 40 second additional circuit arrangement 42 serial peripheral interface 44 digital multi-channel isolator 46 digital isolator 48 ADC reference voltage
Claims
2024P01434 Claims 1. System (10) comprising a low-voltage domain (12) and a high-voltage domain (14), wherein the low-voltage domain (12) and the high-voltage domain (14) are galvanically isolated from each other by an isolation barrier (16), wherein the system (10) has a detection path (20) and an ADC (22) in the high-voltage domain (14) and a microcontroller (18) in the low-voltage domain (12), wherein the detection path (20) can be connected to a high voltage source (24) to receive an input voltage, wherein the detection path (20) has a voltage divider (26), wherein the voltage divider (26) is configured to divide the input voltage into an output voltage with a predetermined division ratio, wherein for voltage measurement the ADC (22) is configured to receive the output voltage from the sensing path (20), convert the output voltage into a digital voltage signal and send the digital voltage signal via the isolation barrier (16) to the microcontroller (18), wherein, for self-testing of the voltage measurement, the ADC (22) is further configured to receive command signals from the microcontroller (18) to control a first general-purpose output (32) of the ADC (22) in the high-voltage domain (14), and wherein the system (10) in the high-voltage domain (14) has a first additional circuit arrangement (34), wherein the first additional circuit arrangement (34) is configured to superimpose an additional voltage (36) on the output voltage after receiving a signal from the first general-purpose output (32) of the ADC (22).
2. System (10) according to claim 1, wherein for overvoltage detection the system (10) has a comparator (28) in the high-voltage domain (14), wherein the comparator (28) is configured to receive the output voltage from the detection path (20) as an input signal, and is further configured to send an output signal across the isolation barrier (16) to the microcontroller (18) if the received input signal is equal to or higher than a predetermined threshold (30), and wherein for self-testing the overvoltage detection the ADC (22) further 2024P01434 is configured to receive command signals from the microcontroller (18) to control a second general-purpose output (38) of the ADC (22) in the high-voltage domain (14), wherein the system (10) in the high-voltage domain (14) has a second additional circuit arrangement (40), and wherein the second additional circuit arrangement (40) is configured to lower the predetermined threshold (30) of the comparator (28) after receiving a signal from the second general-purpose output (38) of the ADC (22).
3. System (10) according to claim 2, wherein the first and second additional circuit arrangement (34, 40) are configured such that when the detection path (20) is not connected to the high voltage source (24) and to the superimposed additional voltage (36), the output voltage of the detection path (20) is higher than the reduced threshold (30) of the comparator (28).
4. System (10) according to one of the preceding claims, wherein the ADC (22) is configured to have bidirectional communication with the microcontroller (18) via a serial peripheral interface (42).
5. System (10) according to claim 4, wherein a bus of the serial peripheral interface (42) crosses the isolation barrier (16) by means of digital isolators (46).
6. System (10) according to one of the preceding claims, wherein the ADC (22) is configured to send a 12-bit signal and / or is configured to send a signal proportional to the received output voltage from the sensing path (20).
7. System (10) according to one of the preceding claims, wherein the system (10) is configured such that the command signals from the microcontroller (18) are command signals of a serial peripheral interface.
8. System (10) according to claim 2, wherein the system (10) is configured such that the output signal of the comparator (28) is transmitted across the isolation barrier (16) by means of a digital isolator (46). 2024P01434 9. At least partially electrically powered motor vehicle comprising a system (10) according to one of the preceding system claims.
10. At least partially electrically powered motor vehicle according to the preceding claim, wherein the high voltage source (24) to which the system (10), and preferably the detection path (20), can be connected is the battery of the vehicle.
11. Method for self-testing a function of a system (10), wherein the system (10) is configured according to one of the preceding system claims, comprising the following steps: Received, by the ADC (22), a command signal to perform a self-test of a voltage measurement from the microcontroller (18), After receiving the command signal, controlling the first multi-purpose output (32) of the ADC (22), so that the first additional circuit arrangement (34) superimposes the additional voltage (36) over the output voltage of the sensing path (20), Receiving the output voltage of the detection path (20) by the ADC (22), Sending, from the ADC (22) to the microcontroller (18), a digital voltage signal based on the received output voltage, and verifying, by the microcontroller (18), that the value of the received digital voltage signal is related to the value of the superimposed additional voltage (36).
12. A method according to the preceding claim, wherein the system (10) is configured according to one of claims 2 or 3, and wherein the method further comprises the following steps: Received, by the ADC (22), a command signal to perform a self-test of an overvoltage detection from the microcontroller (18), After receiving the command signal, triggering an overvoltage detection by controlling the second multi-purpose output (38) of the ADC (22), so that the second additional circuit arrangement (40) lowers the predetermined threshold (30) of the comparator (28), and 2024P01434 Verify, by the microcontroller (18), that the overvoltage detection was triggered by receiving the output signal of the comparator (28).