Sensor control unit, sensor signal receiver, a module with incremental magnetic speed sensor, a method for a sensor control unit, a method for a sensor signal receiver and computer program

Abstract

A sensor control unit (10) for a sensor module (100), comprising at least one interface (12) to receive sensor information from the sensor module (100) and to communicate with a sensor signal receiver (200), in particular an electronic control unit, ECU, of a vehicle; and a control module (14) for: Controlling at least one interface (12), Receiving sensor information from the sensor module (100), Generating a sensor signal based on the sensor information, Transmitting the sensor signal to the sensor signal receiver (200), Detecting a fault condition of the sensor module (100), Deactivating a receiver section of at least one interface (12) if the fault condition does not indicate a failure of the sensor module (100), or Activating the receiver section of at least one interface (12) when the fault condition indicates a failure of at least one part of the sensor module (100), Transmitting a fault indicator to the sensor signal receiver (200) when the fault condition indicates a failure of at least one part of the sensor module (100), receiving, by means of the activated receiver section, a control signal from the sensor signal receiver (200) in response to the fault indicator, wherein the control signal includes at least one fault handling instruction, and executing the at least one fault handling instruction.

Description

Area

[0001] Examples relate to concepts for sensors, and in particular to a sensor control unit, a sensor signal receiver, an incremental magnetic speed sensor module, a method for a sensor control unit, a method for a sensor signal receiver, and a computer program. background

[0002] US 2013 / 0320970 A1 describes a sensor system for detecting errors in the measurement of magnetic field signals, particularly for rotating ferromagnetic objects such as gears. The system uses a threshold and a peak detector operating in parallel to detect anomalies in the magnetic field signal. These anomalies are identified by monitoring logic that monitors signal transitions and detects errors when the expected signal transition sequences deviate. If an error is detected, the sensor system generates an error signal indicating a deviation from the expected signal transition sequences. The error signal can be used to adapt a detection strategy, for example, by calibrating or switching signal processing modes.

[0003] In many fields of technology, data is transferred from one entity to another using a digital coding scheme. While many applications employ sophisticated transmission schemes, in some fields there is a trend toward allowing less complex components of a system to transmit or even exchange data using a robust protocol, allowing both high throughput and a simple implementation or architecture. For example, in motorized systems, a number of low- or medium-complexity sensors can use robust protocols to communicate with one or more complex computing units that collect sensor data transmitted by the sensors.

[0004] There is a need to enable efficient and robust communication between low or medium complexity sensors and complex computing units, in particular to reliably transmit sensor data and detect error conditions without increasing the complexity and energy consumption of the system. Summary

[0005] This need is met by devices according to the independent patent claims. Advantageous further developments are the subject of the dependent claims.

[0006] One embodiment relates to a sensor control unit for a sensor module. The sensor control unit comprises at least one interface for receiving sensor information from the sensor module and for communicating with a sensor signal receiver, in particular an electronic control unit (ECU) of a vehicle. The sensor control unit further comprises a control module for controlling the at least one interface. The control module is configured to receive the sensor information from the sensor module. The control module is further configured to generate a sensor signal based on the sensor information. The control module is further configured to transmit the sensor signal to the sensor signal receiver. The control module is further configured to detect an error state of the sensor module.The control module is further configured to deactivate a receiver section of the at least one interface if the error condition does not indicate a failure of the sensor module and to activate the receiver section of the at least one interface if the error condition indicates a failure of at least part of the sensor module. The control module is further configured to transmit an error indicator to the sensor signal receiver if the error condition indicates a failure of at least part of the sensor module. The control module is further configured to receive, via the activated receiver section, a control signal from the sensor signal receiver in response to the error indicator. The control signal comprises at least one error handling instruction. The control module is further configured to execute the at least one error handling instruction.

[0007] Another embodiment relates to a sensor signal receiver, in particular an ECU of a vehicle. The sensor signal receiver comprises at least one interface for communicating with a sensor control unit of a sensor module. The sensor signal receiver further comprises a control module for controlling the at least one interface. The control module is further configured to receive an error indicator from the sensor control unit via the at least one interface. The control module is further configured to activate a transmitter section of the transmitter section of the at least one interface, which is inactive during normal operation, if the error indicator indicates a failure of at least part of the sensor module. The control module is further configured to provide a control signal to the sensor control unit via the activated transmitter section of the at least one interface in response to the error indicator.The control signal includes at least one error handling instruction.

[0008] Another embodiment relates to a module with an incremental, magnetic speed sensor for automotive use, comprising a sensor control unit. The sensor control unit comprises at least one interface for receiving sensor information from the sensor module and for communicating with a sensor signal receiver, in particular an ECU of a vehicle. The sensor control unit further comprises a control module for controlling the at least one interface. The control module is further configured to receive the sensor information from the sensor module. The control module is further configured to generate a sensor signal based on the sensor information. The control module is further configured to transmit the sensor signal. The control module is further configured to detect an error condition of the sensor module.The control module is further configured to deactivate a receiver section of the at least one interface if the error condition does not indicate a failure of the sensor module and to activate the receiver section of the at least one interface if the error condition indicates a failure of at least part of the sensor module. The control module is further configured to transmit an error indicator to the sensor signal receiver if the error condition indicates a failure of at least part of the sensor module. The control module is further configured to receive, via the activated receiver section, a control signal from the sensor signal receiver in response to the error indicator. The control signal comprises at least one error handling instruction. The control module is further configured to execute the at least one error handling instruction.

[0009] Another example relates to a method for a sensor control unit for a sensor module. The method comprises receiving sensor information from the sensor module. The method further comprises generating a sensor signal based on the sensor information. The method further comprises transmitting the sensor signal. The method further comprises detecting a fault condition of the sensor module. The method further comprises transmitting a fault indicator if the fault condition indicates a failure of at least a portion of the sensor module. The method further comprises receiving a control signal from the sensor signal receiver in response to the fault indicator. The control signal comprises at least one fault handling instruction. The method further comprises executing the at least one fault handling instruction.

[0010] Another example relates to a method for a sensor signal receiver. The method includes receiving a fault indicator from a sensor control unit. The method further includes providing a control signal to the sensor control unit in response to the fault indicator. The control signal includes at least one fault handling instruction.

[0011] Another example relates to a computer program having program code for performing at least one of the above methods when the computer program is executed on a computer, a processor, or a programmable hardware component. Short description of the characters

[0012] Some examples of devices and / or methods are described below solely by way of example and with reference to the accompanying figures, in which Fig. 1 is a block diagram of a sensor control unit for a sensor module; Fig. 1a illustrates a flowchart of a method for a sensor control unit for a sensor module; Fig. 2 shows a block diagram of a sensor signal receiver; Fig. 2a illustrates a flowchart of a method for a sensor signal receiver; Fig. 3 shows a system comprising a sensor control unit and a sensor signal receiver connected via a two-wire connection; and Fig. Figure 4 shows a system comprising a sensor control unit and a sensor signal receiver connected via a three-wire connection. Detailed description

[0013] Various examples will now be described in more detail with reference to the accompanying drawings, which illustrate some examples. In the figures, the thickness of lines, layers, and / or regions may be exaggerated for clarity.

[0014] While further examples are susceptible to various modifications and alternative forms, specific examples thereof are accordingly shown by way of example in the figures and are described in detail herein. However, this detailed description is not limited to the specific forms described. Further examples may cover all modifications, equivalents, and alternatives falling within the scope of the disclosure. Throughout the description of the figures, like reference numerals refer to like or similar elements, which may be implemented identically or in modified form compared to one another while providing the same or similar functionality.

[0015] It is understood that when an element is referred to as being "connected" or "coupled" to another element, the elements may be connected or coupled directly or through one or more intermediate elements. When two elements A and B are connected with an "or," this should be understood to disclose all possible combinations, i.e., only A, only B, and both A and B. An alternative wording for the same combinations is "at least one of A and B." The same applies to combinations of more than two elements.

[0016] The terminology used herein to describe specific examples is not intended to be limiting of further examples. Whenever a singular form such as "a," "an," and "the," is used, and the use of only one element is neither explicitly nor implicitly defined as mandatory, further examples may also include plural elements to implement the same functionality. Where functionality is subsequently described as being implemented using multiple elements, further examples may also implement the same functionality using a single element or processing entity.It is further understood that the terms "comprises," "comprising," "having," and / or "comprising," as used herein, indicate the presence of specified features, integers, steps, operations, processes, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, processes, elements, components, and / or groups thereof.

[0017] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the usual meaning in the field to which the examples belong.

[0018] Fig. 1 illustrates a block diagram of a sensor control unit 10 for a sensor module 100. The sensor control unit 10 comprises at least one interface 12 for receiving sensor information from the sensor module 100 and for communicating with a sensor signal receiver 200. The sensor control unit 10 further comprises a control module 14 for controlling the at least one interface 12. The control module 14 is further configured to receive the sensor information from the sensor module 100. The control module 14 is further configured to generate a sensor signal based on the sensor information. The control module 14 is further configured to transmit the sensor signal.

[0019] Embodiments further provide the sensor module 100, which includes the sensor control unit 10. For example, an incremental magnetic speed sensor module 100 for automotive use (e.g., in an ABS, engine control, or transmission control) may include the sensor control unit. For example, the sensor module 100 may correspond to an automotive sensor module. For example, the sensor module 100 may further include one or more sensors to generate the sensor information. For example, the sensor module 100 may include at least one member from the group comprising an automotive sensor, an (incremental) magnetic speed sensor (for automotive use), and a wheel speed sensor. For example, the sensor module 100 may be included in an anti-lock braking system (ABS), an engine control, or a transmission control.Examples further provide a system including the sensor module 100, the sensor control unit 10, and the sensor signal receiver 200.

[0020] The at least one interface 12 can be configured to receive one or more analog voltages or currents from the sensor module 100 to obtain the sensor information. Alternatively, the at least one interface can be configured to receive one or more digital values ​​to obtain the sensor information. The sensor information can comprise one or more analog values ​​(e.g., currents, voltages, or capacitances) or digital values ​​(e.g., as binary code, temperature code, or pulse-width-modulated values).

[0021] For example, the at least one interface 12 may be configured to communicate with the sensor signal receiver using a wired connection, e.g., a two-wire or three-wire connection. Alternatively, the at least one interface 12 may be configured to communicate wirelessly with the sensor signal receiver 200. The wireless communication may, for example, enable placement of the sensor module within a separate part of a vehicle that includes the sensor signal receiver. The control module 14 may be configured to activate a (wireless) receiver portion of the at least one interface 12 when the fault condition indicates a failure of at least part of the sensor module 100, e.g., while the sensor module and / or the sensor control unit is in a diagnostic mode / safe mode.The control module 14 can be configured to deactivate the (wireless) receiver portion of the at least one interface 12 if the error condition does not indicate a failure of the sensor control unit or the sensor module. This can help reduce energy consumption of the sensor control unit.

[0022] The control module 14 may be configured to measure or interpret one or more analog voltages, currents, or capacitances from the sensor module 100 to obtain the sensor information. Alternatively, the control module 14 may be configured to receive, read, or interpret one or more digital values ​​to obtain the sensor information.

[0023] The control module 14 may, for example, be configured to generate a plurality of consecutive signal edges to generate the sensor signal. For example, a temporal distance or interval between consecutive signal edges may indicate an information content of the sensor signal. For example, the control module 14 may be configured to modulate a current (e.g., a supply current) or to modulate a voltage (e.g., an open-drain voltage) to generate or transmit the sensor signal (and / or diagnostic information). For example, a signal edge within the sensor signal may indicate a pulse of an incremental magnetic speed sensor.

[0024] The control module 14 is further configured to detect an error state of the sensor module 100. For example, the control module 14 can be configured to detect a malfunction of the sensor module 100 in order to detect the error state. For example, the control module 14 can be configured to detect implausible values ​​of the sensor information in order to detect the error state of the sensor module. For example, the control module 14 can be configured to receive information relating to a malfunction of the sensor module 100 from the sensor module 100 in order to detect the error state of the sensor module. The error state of the sensor module 100 can indicate a malfunction of the sensor module 100, e.g., a failure of at least part of the sensor module.

[0025] The control module 14 is further configured to transmit an error indicator (via the at least one interface 12) if the error condition indicates a failure of at least part of the sensor module 100. For example, the error indicator may correspond to a voltage level, a current level, a length of a signal pulse, or a sequence of signal values ​​that are not used for the sensor signal. For example, the control module 14 may be configured to transmit the error indicator instead of the sensor signal if the error condition indicates a failure of at least part of the sensor module 100.

[0026] For example, the control module 14 may be configured to transmit the sensor signal based on two or more sensor signal transmission current levels (e.g., based on current modulation of the supply voltage). The control module 14 may be configured to transmit the fault indicator using a current level above or below (both) the two or more sensor signal transmission current levels. This may enable improved detection of the fault indicator by the sensor signal receiver.

[0027] Alternatively (or additionally), the control module 14 may be configured to transmit the sensor signal based on one or more signal pulses. Pulses of the one or more pulses may have a predefined maximum pulse width (e.g., a longest predefined pulse width). For example, a protocol may use a number (e.g., several) different pulse lengths in normal operation for encoding a direction detection or field strength indication. For example, the pulses of the one or more pulses may have a predefined minimum pulse width and a predefined maximum pulse width. The control module 14 may be configured to transmit the fault indicator by transmitting a pulse with a pulse width that is at least 10% longer (or at least 20% longer, at least 30% longer, at least 50% longer) than the predefined maximum pulse width (of the one or more pulses).This can enable detection of the fault indicator by the sensor signal receiver.

[0028] Alternatively or additionally, each pulse of the one or more pulses may be followed by a (short) protocol frame. For example, the (short) protocol frame may have fewer than 33 bits (or fewer than 17 bits, fewer than 13 bits, fewer than 9 bits, fewer than 5 bits) or corresponding signal edges / values. The control module 14 may be configured to transmit the error indicator using a flag or message encoded within the protocol frame. For example, the protocol frame may include a bit position or a bit field having a bit / flag / signal value or a bit / signal edge sequence indicating the error indicator.

[0029] The control module 14 is further configured to receive a control signal from the sensor signal receiver 200 in response to the fault indicator. For example, the control signal may be based on pulse width modulation or on a binary transmission coding, e.g., Manchester coding.

[0030] The control signal includes at least one error handling instruction. For example, the at least one error handling instruction may include at least one element from the group comprising an instruction to transmit diagnostic information, an instruction to perform a self-test of the sensor module 100, an instruction to obtain diagnostic information from a memory, an instruction to modify one or more parameters of the sensor module, an instruction to modify one or more parameters of the sensor control unit, and an instruction to restart the sensor module and / or the sensor control unit.

[0031] For example, the control module 14 may be configured to accept the at least one error handling instruction (only) after starting the transmission of the error indicator. For example, the control module 14 may be configured to enter a diagnostic mode (a safe mode) based on the transmission of the error indicator. The control module 14 may be configured to execute the at least one error handling instruction (only) while in the diagnostic mode. This may improve operational reliability of the sensor control unit (e.g., by restricting execution of the at least one error handling instruction to safe / diagnostic modes of the sensor control unit).

[0032] The control module 14 is further configured to execute the at least one error handling instruction. For example, the control module 14 may be configured to execute one or more program functions to execute the at least one error handling instruction.

[0033] The sensor control unit can enable adaptation of the sensor module if a failure of at least a portion of the sensor module occurs. For example, the sensor signal receiver can adapt the sensor module in the event of a failure and / or the sensor signal receiver can collect diagnostic information related to the failure.

[0034] For example, the control module 14 may be configured to determine diagnostic information based on the at least one error handling instruction. The diagnostic information may, for example, be used to diagnose the failure, e.g., to enable the sensor signal receiver to provide additional error handling instructions to correct the failure. The control module 14 may be configured to transmit the diagnostic information to the sensor signal receiver 200. For example, the diagnostic information may be based on a self-test of the sensor module 100 or the sensor control unit 10. Alternatively or additionally, the diagnostic information may be based on contents of a memory of the sensor control unit or the sensor module, e.g., status registers or an error log on a programmable memory, e.g., an electronically erasable read-only memory (EEPROM).

[0035] For example, the control module 14 may be configured to perform a self-test of the sensor control unit 10 and / or the sensor module 100 to determine the diagnostic information based on the at least one error handling instruction. The self-test may enable determining a cause of the failure. Alternatively or additionally, the control module 14 may be configured to obtain at least portions of the diagnostic information from a memory (e.g., a register or a programmable memory) of the sensor module 100. Reading a (status) memory for the diagnostic information may enable transmission of predetermined diagnostic information.

[0036] For example, the control module 14 may be configured to modify one or more parameters of the sensor control unit 10 or the sensor module 100 based on the at least one fault handling instruction, e.g., one or more parameters from the group comprising a sensor threshold, a sensor detection parameter, a switching threshold, a hysteresis of the sensor module, an operating mode of the sensor module or the sensor control unit, or a sensor signal resolution. This may enable the sensor control unit to correct the failure. For example, the control module 14 may be configured to set or change one or more values ​​stored in one or more registers to modify the one or more parameters.

[0037] For example, the control module 14 may be configured to restart or reinitialize at least portions of the sensor module 100 and / or the sensor control unit 10 based on the at least one fault handling instruction, e.g., one or more sensors or emitters or a transmission component. For example, some failures may be resolved by restarting portions of the sensor module. For example, the control module 14 may be configured to transmit a reset signal or reset indication to restart or reinitialize at least portions of the sensor module 100 and / or the sensor control unit 10, or to temporarily shut off power to at least portions of the sensor module 100 and / or the sensor control unit 10.

[0038] In at least some embodiments, the at least one interface 12 may be configured to communicate with the sensor signal receiver 200 using a two-wire connection. For example, the two-wire connection may include a supply voltage (wire) and a ground (wire) (as in Fig. 3). The at least one interface 12 may be configured to transmit the sensor signal, the fault indicator, and / or diagnostic information based on current modulation (e.g., the supply voltage). For example, the control module 14 may be configured to adapt a current draw via one of the two wires (e.g., the supply voltage) to transmit the sensor signal, the fault indicator, and / or diagnostic information. Alternatively, the at least one interface 12 may be configured to transmit the sensor signal, the fault indicator, and / or diagnostic information based on voltage modulation. For example, the control module 24 may be configured to transmit the sensor signal, the fault indicator, and / or diagnostic information based on a modulated open-drain voltage or on a modulated power consumption of the sensor module 100.For example, the control signal may be based on voltage modulation of a supply voltage or an open-drain voltage, or may be based on current modulation.

[0039] In various embodiments, the at least one interface may be configured to communicate with the sensor signal receiver 200 using a three-wire connection (e.g., as shown in Fig. 4). The three-wire connection may include a supply voltage (wire), an open-drain voltage (wire), and a ground (wire).

[0040] The at least one interface 12 (and / or at least one interface 22 of Fig. 2) may correspond to one or more inputs and / or outputs for receiving and / or transmitting information, which may be in digital (bit) values ​​according to a specified code, within a module, between modules, or between modules of different entities. In embodiments, the control module 14 (and / or a control module 24 of Fig. 2) be implemented using one or more processing units, one or more processing devices, any means for processing, e.g., a processor, a computer, or a programmable hardware component operable with appropriately adapted software. In other words, the described function of the control module 14; 24 can also be implemented in software, which is then executed on one or more programmable hardware components. Such hardware components can include a general-purpose processor, a digital signal processor (DSP), a microcontroller, etc.

[0041] Fig. 1a illustrates a flowchart of a method for a sensor control unit 10 for a sensor module 100. The method may include one or more features of the control module 14 of Fig. 1. The method comprises obtaining 110 sensor information from the sensor module 100. The method further comprises generating 120 a sensor signal based on the sensor information. The method further comprises transmitting 130 the sensor signal (e.g., to the sensor signal receiver 200). The method further comprises detecting 140 an error condition of the sensor module. The method further comprises transmitting 150 an error indicator (e.g., to the sensor signal receiver 200) if the error condition indicates a failure of at least a portion of the sensor module 100. The method further comprises receiving 160 a control signal from the sensor signal receiver 200 in response to the error indicator. The control signal comprises at least one error handling instruction. The method further comprises executing 170 the at least one error handling instruction.

[0042] Further details and aspects of the method for the sensor control unit will be described in connection with the proposed concept or one or more of the above (e.g. Fig. 1). The method for the sensor control unit may include one or more additional optional features corresponding to one or more aspects of the proposed concept or one or more examples described above or below.

[0043] Fig. 2 illustrates a block diagram of a sensor signal receiver 200. The sensor signal receiver 200 includes at least one interface 22 for communicating with a sensor control unit 10.

[0044] The sensor signal receiver 200 further comprises a control module 24 for controlling the at least one interface 22. The control module 24 is further configured to receive a sensor signal from the sensor control unit 10 via the at least one interface.

[0045] The sensor signal receiver 200 is configured to receive a fault indicator from the sensor control unit 10 via the at least one interface 22, instead of or in place of the sensor signal. For example, the fault indicator may indicate a failure of at least parts of a sensor module 100 comprising the sensor control unit 10. For example, the fault indicator may correspond to a voltage level, a current level, a length of a signal pulse, or a sequence of signal values ​​that are not used for the sensor signal. For example, the control module 24 may be configured to detect the fault indicator based on the voltage level, the current level, the length of a signal pulse, or the sequence of signal values ​​that are not used for the sensor signal.

[0046] The control module 24 is configured to provide a control signal to the sensor control unit 10 via the at least one interface 22 in response to the error indicator. The control signal includes at least one error handling instruction.

[0047] Receiving the fault indicator may alert the sensor signal receiver of a failure of at least a portion of a sensor module 100 comprising the sensor control unit 10. Providing the control module may enable diagnosis or correction of the failure.

[0048] For example, the at least one error handling instruction may comprise at least one element from the group comprising an instruction to transmit diagnostic information, an instruction to perform a self-test of a sensor module 100 comprising the sensor control unit 10, an instruction to obtain diagnostic information from a memory of the sensor control unit 10 or the sensor module 100, an instruction to modify one or more parameters of the sensor module 100, an instruction to modify one or more parameters of the sensor control unit 10, and an instruction to restart the sensor module and / or the sensor control unit.

[0049] The control module 24 may, for example, be configured to generate a plurality of consecutive signal edges to generate the control signal. For example, a temporal distance or interval between consecutive signal edges may indicate an information content of the control signal. For example, the control module 24 may be configured to modulate a current or to modulate a voltage (e.g., an open-drain voltage or a supply voltage) to generate or transmit the control signal.

[0050] For example, the control module 24 may be configured to determine the at least one error instruction based on the error indicator, e.g., based on a failure of at least a portion of the sensor control unit or the sensor module indicated by the error indicator. For example, the control module 24 may be configured to transmit the at least one error handling instruction regardless of an information content of the error indicator. Alternatively, the control module 24 may select one or more of a plurality of error handling instructions for the control signal based on the error indicator (e.g., based on an error state of the sensor module 100 indicated by the error indicator).

[0051] In at least some embodiments, the at least one interface 22 may be configured to communicate with the sensor control unit 20 using a two-wire connection. For example, the two-wire connection may include a supply voltage (wire) and a ground (wire) (as in Fig. 3). The at least one interface 22 can be configured to receive the sensor signal, the error indicator, and / or diagnostic information based on current modulation (e.g., the supply voltage) or based on voltage modulation. For example, the control module 24 can be configured to transmit the control signal based on a modulated open-drain voltage or on a modulated supply voltage. For example, the control signal can be based on voltage modulation of a supply voltage or an open-drain voltage, or can be based on current modulation. For example, the control module 24 can be configured to transmit the control signal by modulating the control signal onto a supply voltage and / or to receive the error indicator based on a modulated open-drain voltage or based on a modulated current consumption of the sensor.

[0052] In some embodiments, the control module 24 may further be configured to receive diagnostic information from the sensor control unit 10 via the at least one interface 22 in response to the control signal. This may enable a diagnosis of the failure of the sensor module and / or the sensor control unit. For example, the control module 24 may further be configured to forward the diagnostic information to a vehicle control entity of a vehicle that includes the sensor signal receiver. Alternatively or additionally, the control module 24 may be configured to adapt the control signal and / or the one or more error handling instructions based on the diagnostic information, e.g., to retrieve further diagnostic information or to adapt one or more parameters of the sensor control unit or the sensor module.

[0053] Further details and aspects of the sensor signal receiver will be described in connection with the proposed concept or one or more of the above (e.g. Fig. 1 to 1a). The sensor signal receiver may have one or more additional optional features corresponding to one or more aspects of the proposed concept or one or more examples described above or below.

[0054] Fig. 2a illustrates a flowchart of a method for a sensor signal receiver 200. The method may include one or more features of the control module 24 of Fig. 2. The method includes receiving 210 an error indicator from a sensor control unit 10. The method further includes providing 220 a control signal to the sensor control unit 10 in response to the error indicator. The control signal includes at least one error handling instruction.

[0055] Further details and aspects of the method for the sensor signal receiver will be described in connection with the proposed concept or one or more of the above (e.g. Fig. 1 to 2). The method for the sensor signal receiver may have one or more additional optional features corresponding to one or more aspects of the proposed concept or one or more of the examples described above or below.

[0056] At least some examples provide wheel speed sensors (e.g., sensor modules 100) that open a diagnostic channel in the event of a fault detection. At least some embodiments may provide a sensor that has already detected and signaled a fault (a fault condition) in a state that allows the ECU (Electronic Control Unit; ECU = Electronic Control Unit), e.g., the sensor signal receiver 200), to read internal fault detection information or initiate additional tests.

[0057] Incremental speed sensors can use a 2-wire interface with current modulation, representing threshold crossings of a magnetic field through edges or pulses that switch between two or three current consumption states. Alternatively, 3-wire open-drain interfaces can be used to transmit the same type of information. Some sensors have the ability to provide limited additional information of a few bits following the edge or pulse.

[0058] Furthermore, some sensors (e.g., the sensor control unit 10) may also execute safety measures and enter a safe state by sending an error message (e.g., a fault indicator). During normal operation, the sensor having a safety mechanism may be compatible with other sensors for the same application (e.g., wheel speed, transmission, camshaft, crankshaft). If an internal safety mechanism detects an error, it enters a safe state, e.g., by switching to an error signal level half the low level of regular communication or by sending at least one signal that can be recognized as an impermissible speed pulse (e.g., an increased speed pulse). Some sensors may not allow (at all) access to internal data or the execution of commands upon request from the ECU.

[0059] Once the safety measure is activated, the sensor (e.g., a sensor control unit) may enable a receiver that can be deactivated during normal operation and configured to listen to messages from the ECU. Alternatively, the ECU may include a transmitter that is also inactive during normal operation and may be activated once the ECU detects that the sensor has switched to the safe state.

[0060] The ECU message can be sent by supply voltage modulation for both sensor interfaces (2-wire interface (e.g. wheel speed or transmission) or 3-wire open drain (camshaft or crankshaft)).

[0061] If the ECU sends at least one detectable pulse or (preferably in some cases) a decodable command message, the sensor may be configured to respond by executing an exception routine and providing information back to the ECU.

[0062] Exception routines can be, for example: • Empty all or a selection of internal registers • Writing data to internal registers, e.g. to modify a switching threshold or hysteresis. • Perform a self-test and return the result • Execution of an initialization routine that allows a return to normal operation more quickly than would be the case with a restart, whereby the sensor supply is switched off, which is controlled by the ECU, and reinitialized by a new power-up.

[0063] The ECU message can also be transmitted over the open-drain connection of a 3-wire interface if the safe state of the interface turns off the open-drain switch. In this case, the ECU can also use an open-drain transistor to pull down the communication line in case it is transmitting; on the other hand, in the case of fault diagnostics, communication may require higher data rates and thus both sides may also have push-pull drivers for this communication mode (in the case of the ECU, a normal microcontroller tristate output can be used as a transmitter). This can allow the diagnostic communication to fail due to its high state, which is closer to V dd than the normal open-drain velocity pulses can be detected.

[0064] A 3-wire system can also use the supply lines and combine both communication channels, e.g. to establish full-duplex communication with, for example, the sensor transmitting via its usual output while the ECU modulates the supply.

[0065] Fig. Figure 3 shows an exemplary system including a sensor control unit 10 and a sensor signal receiver 200 connected via a two-wire connection. The two-wire connection has a supply voltage (V dd ) wire 308 and a ground (GND) wire 309. The sensor control unit 10 may include a safety mechanism 302 to prevent transmission 304 of a fault indicator via current modulation to the sensor signal receiver 200 using the supply voltage V dd308 and to enable receiving 306 a control signal via a voltage modulation of the supply voltage 308 from the sensor signal receiver 200. The sensor signal receiver 200 may include a sensor safe state detector 312 (e.g., the control module 24 of Fig. 2) to enable receiving 314 of the fault indicator (based on the current modulation) and to enable transmitting 316 of the control signal (based on the voltage modulation). For example, the sensor control unit may be configured to transmit a sensor signal 320 to the sensor signal receiver based on the current modulation, e.g., based on a first current draw 322 and a second current draw 324 of a supply current I VddThe sensor control unit may further be configured to transmit the fault indicator based on a third current draw 326 of the supply current. In response to the fault indicator, the sensor signal receiver may be configured to transmit a control signal 328 comprising a pulse or a message (based on a voltage modulation of the supply voltage). In response to the control signal, the sensor control unit may be configured to transmit diagnostic information 330 to the sensor signal controller (based on a current modulation of the supply current).

[0066] Fig. Figure 4 shows an exemplary system including a sensor control unit 10 and a sensor signal receiver 200 connected via a three-wire connection. The three-wire connection has a supply voltage (V dd ) wire 407, an open-drain voltage (V od) wire 408, a ground (GND) wire 409 and a pull-up resistor 410. The sensor control unit 10 may include a safety mechanism 402 (e.g., the control module 14 of Fig. 1) to enable transmission 404 of a fault indicator via a current modulation of the open-drain voltage V od 408 to the sensor signal receiver 200 and to enable receiving 406 a control signal via a voltage modulation of the open-drain voltage 408 from the sensor signal receiver 200. The sensor signal receiver 200 may include a sensor safe state detector 412 (e.g., the control module 24 of Fig. 2) to enable receiving 414 of the fault indicator (based on the voltage modulation of the open-drain voltage) and to enable transmitting 416 of the control signal (based on the voltage modulation of the open-drain voltage). For example, the sensor control unit may be configured to transmit a sensor signal 420 to the sensor signal receiver based on the current modulation, e.g., based on a first voltage 422 and a second voltage 424 of an open-drain voltage V odThe sensor control unit may further be configured to transmit the fault indicator based on a remaining 426 at the first voltage 424. In response to the fault indicator, the sensor signal receiver may be configured to transmit a control signal 428 comprising a pulse or a message (based on a voltage modulation of the open-drain voltage). In response to the control signal, the sensor control unit may be configured to transmit diagnostic information 430 to the sensor signal controller (based on a voltage modulation of the open-drain voltage).

[0067] Various modulation schemes and a protocol mechanism, known from communication systems, can be used during the diagnostic state. The communication protocol, for example, when the sensor has entered the diagnostic state can be proprietary, such as the SICI (Serial Inspection and Configuration Interface), which is already used for testing and programming purposes in many sensors. It can also include a standard-like PSI5 (Peripheral Sensor Interface 5) or DSI3 (Distributed Systems Interface 3) for the 2-wire interface or SPC (Short Pulse Width Modulation Code) for 3-wire communication. Embodiments can be used, for example, in sensor integrated circuits as well as customer systems.

[0068] In some embodiments, the ECU may be configured to activate a diagnostic mode even during normal operation, e.g., when it can be avoided that a communication protocol other than speed pulses can be interpreted.

[0069] At least some embodiments may be based on opening a diagnostic communication channel in the event that a sensor enters a safe state, e.g., for a narrow time window. At least some embodiments may extend the diagnostic capability of speed sensors to high ASIL (Automotive Safety Integrity Level) levels.

[0070] Further details and aspects of the method will be described in connection with the proposed concept or one or more of the above (e.g. Fig.1 to 2a). The concept may have one or more additional optional features corresponding to one or more aspects of the proposed concept or one or more examples described above or below.

[0071] The aspects and features mentioned and described together with one or more of the examples and figures described in detail above may also be combined with one or more of the other examples to replace a similar feature of the other example or to additionally introduce the feature into the other example.

[0072] Examples may further include, or relate to, a computer program including program code for performing one or more of the above methods when the computer program is executed on a computer or processor. Steps, operations, or processes of various methods described above may be performed by programmed computers or processors. Examples may also cover program storage devices, e.g., digital data storage media, that are machine-, processor-, or computer-readable and encode machine-executable, processor-executable, or computer-executable programs of instructions. The instructions perform or cause the performance of some or all of the steps of the above-described methods. The program storage devices may be, for example, digital memories, magnetic storage media such as magnetic disks and magnetic tapes, hard disk drives, or optically readable digital data storage media.Also, further examples are intended to cover computers, processors or control units programmed to perform the steps of the methods described above or (field) programmable logic arrays ((F)PLA = (Field) Programmable Logic Arrays) or (field) programmable gate arrays ((F)PGA = (Field) Programmable Gate Arrays) programmed to perform the steps of the methods described above.

[0073] The description and drawings represent only the principles of the disclosure. Furthermore, any examples provided herein are expressly intended to be for educational purposes only, to assist the reader in understanding the principles of the disclosure and the concepts contributed by the inventor(s) to advance the art. All statements herein regarding principles, aspects, and examples of the disclosure, as well as specific examples thereof, are intended to include equivalents thereof.

[0074] A functional block referred to as a "means for..." performing a certain function may refer to a circuit configured to perform a specific function. Thus, a "means for something" may be implemented as a "means configured for or suitable for something," e.g., a device or circuit configured for or suitable for the respective task.

[0075] Functions of various elements shown in the figures, including any functional blocks referred to as "means," "means for providing a sensor signal," "means for generating a transmission signal," etc., may be provided in the form of dedicated hardware such as "a signal provider," "a signal processing unit," "a processor," "a controller," etc., as well as hardware capable of executing software in conjunction with associated software. When provided by a processor, the functions may be provided by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some or all of which may be shared.However, the term "processor" or "controller" is by no means limited exclusively to hardware capable of executing software, but may include digital signal processor (DSP) hardware, network processor, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), read-only memory (ROM) for storing software, random access memory (RAM), and non-volatile storage devices. Other hardware, conventional and / or custom, may also be included.

[0076] For example, a block diagram may represent a detailed circuit diagram implementing the principles of the disclosure. Similarly, a sequence diagram, a flowchart, a state transition diagram, pseudocode, and the like may represent various processes, operations, or steps substantially embodied in computer-readable medium and thus capable of being performed by a computer or processor, regardless of whether such a computer or processor is explicitly depicted. Methods disclosed in the description or claims may be implemented by an apparatus having means for performing each of the respective steps of these methods.

[0077] It should be understood that the disclosure of multiple steps, processes, operations, or functions disclosed in the specification or claims should not be construed as being in that particular order unless explicitly or implicitly stated otherwise, e.g., for technical reasons. Therefore, the disclosure of multiple steps or functions does not limit them to any particular order unless those steps or functions are not interchangeable for technical reasons. Furthermore, in some examples, a single step, function, process, or operation may include or be broken down into multiple sub-steps, functions, processes, or operations. Such sub-steps may be included and be part of the disclosure of that single step unless expressly excluded.

[0078] Furthermore, the following claims are hereby incorporated into the Detailed Description, where each claim may stand on its own as a separate example. While each claim may stand on its own as a separate example, it should be noted that although a dependent claim may refer to a specific combination with one or more other claims in the claims, other examples may include a combination of the dependent claim with the subject matter of any other dependent or independent claim. These combinations are explicitly suggested herein unless it is stated that a particular combination is not intended. Furthermore, features of a claim for any other independent claim are also intended to be included, even if that claim is not made directly dependent on the independent claim.

Claims

[1] A sensor control unit (10) for a sensor module (100), comprising at least one interface (12) for receiving sensor information from the sensor module (100) and for communicating with a sensor signal receiver (200), in particular an electronic control unit, ECU, of a vehicle; and a control module (14) for: Controlling the at least one interface (12), Obtaining the sensor information from the sensor module (100), Generating a sensor signal based on the sensor information, Transmitting the sensor signal to the sensor signal receiver (200), Detecting an error condition of the sensor module (100), Deactivating a receiver section of the at least one interface (12) if the error condition does not indicate a failure of the sensor module (100), or Activating the receiver section of the at least one interface (12) when the error condition indicates a failure of at least part of the sensor module (100), Transmitting an error indicator to the sensor signal receiver (200) if the error condition indicates a failure of at least part of the sensor module (100), receiving, by means of the activated receiver section, a control signal from the sensor signal receiver (200) in response to the error indicator, wherein the control signal comprises at least one error handling instruction, and executing the at least one error handling instruction. [2] The sensor control unit (10) according to claim 1, wherein the control module (14) is configured to determine diagnostic information based on the at least one error handling instruction and to transmit the diagnostic information to the sensor signal receiver (200). [3] The sensor control unit (10) according to claim 2, wherein the control module (14) is configured to perform a self-test of the sensor control unit (10) and / or the sensor module (100) to determine the diagnostic information based on the at least one error handling instruction. [4] The sensor control unit (10) according to one of claims 2 or 3, wherein the control module (14) is configured to obtain at least parts of the diagnostic information from a memory of the sensor module (100). [5] The sensor control unit (10) according to one of the preceding claims, wherein the control module (14) is configured to modify one or more parameters of the sensor control unit (10) or the sensor module (100) based on the at least one error handling instruction. [6] The sensor control unit (10) according to one of the preceding claims, wherein the control module (14) is configured to restart at least parts of the sensor module (100) and / or the sensor control unit (10) based on the at least one error handling instruction. [7] The sensor control unit (10) according to one of the preceding claims, wherein the control module (14) is configured to accept the at least one error handling instruction after the start of the transmission of the error indicator. [8] The sensor control unit (10) according to any one of the preceding claims, wherein the control module (14) is configured to enter a diagnostic mode based on transmitting the error indicator, and wherein the control module (14) is configured to execute the at least one error handling instruction while in the diagnostic mode, and / or wherein the control module (14) is configured to transmit the error indicator instead of the sensor signal when the error condition indicates a failure of at least part of the sensor module (100). [9] The sensor control unit (10) according to any one of the preceding claims, wherein the control module (14) is configured to transmit the sensor signal based on two or more sensor signal transmission current levels, and wherein the control module (14) is configured to transmit the error indicator by using a current level above or below the two or more sensor signal transmission current levels, and / or wherein the control module (14) is designed to transmit the sensor signal based on one or more signal pulses, wherein pulses of the one or more pulses have a predefined maximum pulse width, and wherein the control module (14) is designed to transmit the error indicator by transmitting a pulse with a pulse width that is at least 10% longer than the predefined maximum pulse width, and / or wherein the control module (14) is configured to transmit the sensor signal based on one or more signal pulses, wherein each pulse of the one or more pulses is followed by a protocol frame, and wherein the control module (14) is configured to transmit the error indicator using a flag or message encoded within the protocol frame. [10] The sensor control unit (10) according to one of the preceding claims, wherein the at least one interface (12) is configured to communicate with the sensor signal receiver (200) using a two-wire connection, and wherein the at least one interface (12) is configured to transmit the sensor signal and / or diagnostic information based on current modulation. [11] The sensor control unit (10) according to any one of the preceding claims, wherein the control signal is based on a voltage modulation of a supply voltage or an open-drain voltage. [12] The sensor control unit (10) according to one of the preceding claims, wherein the at least one interface (12) is designed to communicate wirelessly with the sensor signal receiver (200). [13] The sensor control unit (10) according to claim 12, wherein the control module (14) is configured to activate a wireless receiver portion of the at least one interface (12) when the fault condition indicates a failure of at least a portion of the sensor module (100). [14] A sensor signal receiver (200), in particular an ECU of a vehicle, comprising: at least one interface (22) to communicate with a sensor control unit (10) for a sensor module (100); a control module (24) for: Controlling the at least one interface (22), Receiving an error indicator from the sensor control unit (10) via the at least one interface (22), Activating a transmitter section of the at least one interface (22) that is inactive during normal operation when the error indicator indicates a failure of at least part of the sensor module (100), and Providing a control signal to the sensor control unit (10) via the activated transmitter section of the at least one interface (22) in response to the error indicator, wherein the control signal comprises at least one error handling instruction. [15] The sensor signal receiver (200) according to claim 14, wherein the control module (24) is further configured to receive diagnostic information from the sensor control unit (10) via the at least one interface (22) in response to the control signal. [16] The sensor signal receiver (200) according to one of claims 14 or 15, wherein the at least one interface (24) is configured to transmit the control signal by modulating the control signal to a supply voltage and to receive the error indicator based on a modulated open-drain voltage or on a modulated current consumption of the sensor. [17] An incremental magnetic speed sensor module (100) for automotive use, comprising a sensor control unit (10) according to any one of claims 1 to 13.

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