Controller area network (CAN) transceiver, CAN device, CAN system and method for CAN transceiver

Abstract

The invention relates to a controller area network (CAN) transceiver comprising a transmit data (TXD) interface, a receive data (RXD) interface, a bus interface for coupling to a CAN bus, a receiver unit, a transmitter unit and a wake-up unit, in which the bus interface is configured to receive a first differential voltage signal, referred to as a bus signal, from the CAN bus via the bus interface, wherein the wake-up unit is configured to detect an end of frame (EOF) field representing the first CAN frame in the bus signal and / or a quiet section of an intermittent space (ITM) following the EOF field based on the bus signal, wherein the wake-up unit is configured to detect at least one wake-up pulse having a differential bus voltage less than a first predefined negative threshold voltage (TH1) in a silence section of the bus signal. The invention also relates to a CAN device, a CAN system and a method for a CAN transceiver.

Description

Technical Field

[0001] The present disclosure relates to a CAN transceiver, a CAN device, a CAN system, and a method for a CAN transceiver. Background Art

[0002] Controller Area Network (CAN) can be used for in-vehicle communication, especially for automotive in-vehicle communication. It should be understood that CAN is also applied outside the automotive field. A CAN bus system can include multiple CAN devices, so-called nodes or electronic control units (ECUs), such as engine control modules (ECMs), powertrain control modules (PCMs), airbags, anti-lock brakes, cruise control, electric power steering, audio systems, windows, doors, rearview mirror adjustments, battery and recharge systems for hybrid / electric vehicles, etc. Several nodes can be connected to a joint CAN bus, such that the nodes can communicate with each other via the CAN bus using the CAN protocol. The CAN protocol is used to enable communication between individual nodes. The data link layer of the CAN protocol is standardized as International Organization for Standardization (ISO) 11898-1:2003. CAN Flexible Data Rate or “CAN FD” is an extension of the standardized CAN data link layer protocol and is incorporated into the ISO 11898-1:2015 standard. CAN FD can provide a higher data rate. The standardized CAN data link layer protocol is being further extended to provide an even higher data rate. Another extension called CAN XL, in which an optional level scheme regarding the physical layer allows an even higher data rate, is in the definition phase according to CiA610 (CAN in Automation) and is evolving towards standardization in the form of ISO 11898-1:202x. Summary of the Invention

[0003] This Summary of the Invention is provided to introduce a series of concepts that are further described below in the Detailed Description in a simplified form. This Summary of the Invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0004] Aspects of the present disclosure are defined in the appended claims.

[0005] According to a first aspect of the present disclosure, a Controller Area Network (CAN) transceiver is provided. The CAN transceiver includes: a transmit data (TXD) interface, a receive data (RXD) interface, a bus interface for coupling to a CAN bus, a receiver unit, a transmitter unit, and a wake-up unit, wherein the bus interface is configured to receive, via the bus interface, a first differential voltage signal called a bus signal from the CAN bus, wherein the wake-up unit is configured to detect an end-of-frame (EOF) field of a first CAN frame and / or an intermission time (ITM) silent section following the EOF field in the bus signal, wherein the wake-up unit is configured to detect at least one wake-up pulse having a differential bus voltage less than a first predefined negative threshold voltage in the silent section of the bus signal, and wherein the wake-up unit is configured to cause a wake-up signal representing a wake-up instruction to be sent via an interface of the transceiver in response to the detected at least one wake-up pulse, the interface being specifically the RXD interface or another interface of the transceiver.

[0006] In one or more embodiments, the wake-up unit is configured to detect a trigger pulse based on the bus signal, the trigger pulse having a differential bus voltage greater than a positive predefined second threshold voltage, wherein the wake-up unit is configured to wait for a predefined waiting time after the trigger pulse, wherein the wake-up unit is configured to detect a base section of the bus signal based on the bus signal, wherein during a predefined base time after the waiting time, the base section has a differential bus voltage between a first threshold voltage and the second threshold voltage, wherein the wake-up unit is configured to detect an observation section of the bus signal based on the bus signal, wherein during a predefined observation time after the base time, the observation section has a differential bus voltage less than the second threshold voltage, wherein the observation section forms at least a part of the silent section, and wherein the wake-up unit is configured to detect at least one wake-up pulse having a differential bus voltage less than the first threshold voltage in the observation section of the bus signal.

[0007] In one or more embodiments, the waiting time is between 0.01 μs and 2 μs, specifically between 0.1 μs and 1.3 μs, and / or wherein the base time is between 2 times and 7 times the cycle time according to a predefined bit frequency at the bus interface, and / or wherein the observation time is between 5 times and 7 times the cycle time according to the predefined bit frequency at the bus interface.

[0008] In one or more embodiments, the second threshold voltage is between positive 0.5 volts and positive 0.9 volts.

[0009] In one or more embodiments, the first threshold voltage is between negative 0.25 volts and negative 0.45 volts.

[0010] In one or more embodiments, the wake-up unit is configured to detect a predefined wake-up pattern in the silent section, the predefined wake-up pattern including a plurality of wake-up pulses, each wake-up pulse having a differential bus voltage less than the first predefined negative threshold voltage, and wherein the wake-up unit is configured to cause a wake-up signal indicative of a wake-up instruction to be specifically sent via the RXD interface or another interface of the transceiver in response to the detected wake-up pattern.

[0011] In one or more embodiments, the wake-up unit is coupled to the receiver unit and / or the RXD interface to cause the transmission of the wake-up signal.

[0012] In one or more embodiments, the CAN transceiver and / or the receiver unit is configured to treat the wake-up pulse as a recessive bit.

[0013] In one or more embodiments, the wake-up unit is configured to control the receiver unit such that the receiver unit generates a signal indicative of a recessive bit at the RXD interface based on the wake-up pulse.

[0014] In one or more embodiments, the wake-up unit is configured to detect a first section of the bus signal, the first section representing at least one of a start-of-frame field SOF, an arbitration field, and / or a control field of the first CAN frame, wherein the wake-up unit is configured to detect another pattern called a reference pattern represented by the first section of the bus signal, and wherein the wake-up unit is configured to form the wake-up signal only when and / or after detecting the reference pattern.

[0015] In one or more embodiments, the CAN transceiver, when activated, is configured to receive a control instruction for issuing a wake-up pattern via an interface other than the bus interface of the transceiver, wherein the CAN transceiver is configured to receive another CAN frame called a second CAN frame via the TXD interface, and wherein the CAN transceiver is configured to send an output signal via the bus interface such that the output signal represents the second CAN frame, except that an instruction section of the EOF and / or the ITM representing the CAN frame in the output signal further includes at least one wake-up pulse having a differential bus voltage less than the first threshold voltage.

[0016] According to a second aspect of the present disclosure, a CAN device is provided. The CAN device includes: a CAN transceiver according to the first aspect and / or any corresponding embodiment, and a CAN controller, wherein the CAN controller is coupled to the TXD interface of the CAN transceiver and the RXD interface of the CAN transceiver, wherein the wake-up unit of the CAN transceiver is configured to cause the wake-up signal to be sent to the CAN controller via the RXD interface or another interface of the CAN transceiver in response to a detected wake-up pulse or a detected wake-up pattern, and wherein the CAN controller is configured to change from an inactive state to an operating state in response to the received wake-up signal.

[0017] According to a third aspect of the present disclosure, a CAN system is provided. The CAN system includes: a CAN bus, a first CAN transceiver according to the first aspect and / or any corresponding embodiment, and a second CAN transceiver according to the first aspect and / or any corresponding embodiment, wherein the wake-up unit of the first CAN transceiver is configured to detect a first wake-up pattern as a wake-up pattern, wherein the wake-up unit of the second CAN transceiver is configured to detect a second wake-up pattern as another wake-up pattern, and wherein the first wake-up pattern and the second wake-up pattern are different.

[0018] In one or more embodiments, the CAN system includes: a first CAN device according to the second aspect; a second CAN device according to the second aspect, wherein the first CAN device includes a first transceiver as a transceiver, and wherein the second CAN device includes a second transceiver as a transceiver.

[0019] According to a fourth aspect of the present disclosure, a method for a CAN transceiver is provided. The CAN transceiver includes a transmit data TXD interface, a receive data RXD interface, a bus interface for coupling to a CAN bus, a receiver unit, a transmitter unit, and a wake-up unit. The method includes the following steps: (a) receiving, at the bus interface, a first differential voltage signal referred to as a bus signal, (b) the wake-up unit detecting an end-of-frame EOF field of a CAN frame represented in the bus signal and / or an intermission space ITM silent section following the EOF field based on the bus signal, (c) the wake-up unit detecting at least one wake-up pulse having a differential bus voltage less than a first predefined negative threshold voltage (TH1) in the silent section of the bus signal, and (d) the wake-up unit causing a wake-up signal representing a wake-up instruction to be sent via an interface of the transceiver in response to the detected at least one wake-up pulse, the interface being specifically the RXD interface or another interface of the transceiver.

[0020] According to a fifth aspect of the present disclosure, there is provided a computer program comprising executable instructions which, when executed by a processing unit of a transceiver, cause the processing unit to be configured to perform the method of the fourth aspect and / or one or more embodiments of the method. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. However, it should be noted that the drawings only show typical embodiments of the present disclosure and should not be considered as limiting the scope of the present disclosure, such that other equally effective embodiments can be implemented. For those skilled in the art, after reading this specification in conjunction with the drawings, the advantages of the claimed subject matter will become apparent. In the drawings, the same reference numerals are used to denote the same elements, and in the drawings:

[0022] Figure 1 An embodiment showing a simplified block diagram of a CAN system is shown.

[0023] Figure 2 An embodiment showing a simplified block diagram of a CAN device is shown.

[0024] Figure 3 An embodiment showing a waveform is shown.

[0025] Figure 4 An embodiment showing a simplified CAN XL frame is shown.

[0026] Figure 5 An embodiment showing a simplified CAN frame is shown.

[0027] Figure 6 Another embodiment showing a simplified waveform is shown.

[0028] Figure 7 Another embodiment showing a simplified block diagram of a CAN device is shown.

[0029] Figure 8 An embodiment showing a simplified flowchart is shown.

[0030] Figure 9 An embodiment showing a simplified method flowchart is shown. DETAILED DESCRIPTION

[0031] As indicated in the background art section of the present disclosure, Controller Area Network (CAN) can be used for communication, specifically for communication within a vehicle. It should be understood that CAN communication is also applied outside the vehicle field.

[0032] Figure 1An example of a CAN system 100 is schematically shown. The CAN system may include a number of CAN devices 102 and a CAN bus 104. Each CAN device 102 may be connected to the CAN bus 104. Thus, the CAN devices 102 are able to communicate with each other via the CAN bus 104. The CAN devices 102 may also be referred to as CAN nodes. In the example, the CAN device 102 may be at least a part of an electronic control unit (ECU), such as an engine control module (ECM), a powertrain control module (PCM), an airbag module, an anti-lock braking module, a cruise control module, an electric power steering module, an audio module, a window module, a door module, a rearview mirror adjustment module, a battery module for a hybrid / electric vehicle (specifically, a battery management module), a recharging module, and / or other modules.

[0033] The CAN protocol may enable communication via the CAN bus 104. For example, the CAN protocol may enable communication between at least two CAN devices 102. In the example, each CAN device 102 includes a CAN transceiver 120 and a microcontroller 110 having an embedded CAN controller 114. The CAN controller 114 may also be referred to as a controller or a CAN protocol controller. The CAN transceiver 120 may also be referred to as a transceiver.

[0034] The microcontroller 110 may be connected to at least one other device (not shown), such as a sensor, an actuator, or some other control device. The microcontroller 110 may be programmed to determine the meaning of the received message and / or generate an appropriate outgoing message. The microcontroller 110, which may also be referred to as a host processor, a host, or a digital signal processor (DSP). In the example, the microcontroller 110 may support application software that interacts with the CAN controller 108.

[0035] The CAN bus 104 is preferably configured to carry analog differential signals, specifically, differential voltage signals representing CAN frames. The CAN bus 104 may include a first signal line 124 referred to as the first CAN signal line 124 and / or the CAN high (CANH) bus line 124. The CAN bus 104 may also include a second signal line 126 referred to as the second CAN signal line 126 and / or the CAN low (CANL) bus line 126.

[0036] Figure 2An example of the CAN device 102 is schematically shown. The CAN device 102 includes a CAN transceiver 120 and a CAN controller 114. In the example, the CAN device 102 includes a microcontroller 110, and the microcontroller 110 includes the CAN controller 114. If favorable explanations, preferred features, technical effects, and / or advantages regarding the CAN device 102 are presented hereinafter, these favorable explanations, preferred features, technical effects, and / or advantages can be applied to the CAN transceiver 120 in a similar manner.

[0037] The CAN transceiver 120 may include a transmit data TXD interface 128. The TXD interface 128 of the CAN transceiver 120 may also be referred to as the first TXD interface 128. The CAN transceiver 120 may further include a receive data RXD interface 130. The RXD interface 130 of the CAN transceiver 120 may also be referred to as the first RXD interface 130. The CAN transceiver 120 may include another interface 220. This another interface 220 may also be referred to as the first wake-up interface 220. The CAN transceiver 120 may include another interface 224. This another interface 224 may also be referred to as the first control interface 224.

[0038] The CAN controller 114 may include a TXD interface 216 that may be referred to as the second TXD interface 216. Additionally, the CAN controller 114 may include an RXD interface 218 referred to as the second RXD interface 218. In the example, the CAN controller 114 may include another interface 222 referred to as the second wake-up interface 222. The CAN controller 114 may include another interface 226 referred to as the second control interface 226.

[0039] In the example, the first TXD interface 128 of the CAN transceiver 120 is coupled to the second TXD interface 216 of the CAN controller 114 via a signal connection 228. In the example, the CAN controller 114 may be configured to generate a signal representing a CAN frame at the second TXD interface 210, and this signal is referred to as the TXD signal. The CAN frame includes a plurality of bits.

[0040] The CAN transceiver 120 includes another interface 132 referred to as a bus interface 132. In the example, the bus interface 132 includes a first bus terminal 212 and a second bus terminal 214. The first bus terminal 212 is configured to be connected to a first CAN bus line 124. The second bus terminal 214 is configured to be connected to a second CAN bus line 126.

[0041] The CAN transceiver 120 includes a transmitter unit 138. The transmitter unit 138 can be coupled to the first TXD interface 128. Via the first TXD interface 128, the transmitter unit 138 can receive a TXD signal representing a CAN frame. The transmitter unit 138 can be additionally coupled to the bus interface 132. The transmitter unit 138 can be configured to generate a bus signal at the CAN bus interface 132 based on the received CAN frame such that the bus signal represents the CAN frame. The bus signal is preferably a differential voltage signal. The corresponding voltage difference refers to the difference between the voltage at the first bus terminal 212 and the voltage at the second bus terminal 214.

[0042] The CAN transceiver 120 includes a receiver unit 136. The receiver unit 136 can be coupled to the CAN bus interface 132. The receiver unit 136 can receive the bus signal 142 via the CAN bus interface 132. The bus signal 142 can also be referred to as the CAN bus signal 142. Figure 3 An example of the bus signal 142 is schematically shown. The bus signal 142 can be generated by another CAN device 102 and sent via the CAN bus 104 to the CAN bus interface 132 of the Figure 2 CAN transceiver 120. In the example, the CAN bus signal 142 can represent Figure 3 the CAN frame 148 schematically and exemplarily shown in. The CAN frame 148 is also referred to as the first CAN frame 148.

[0043] The receiver unit 136 of the CAN transceiver 120 can be coupled to the first RXD interface 130. The first RXD interface 130 can be coupled to the second RXD interface 218 of the CAN controller 114 via a signal connection 230. In the example, the receiver unit 136 can be configured to generate an RXD signal at the first RXD interface 130 based on the first CAN frame 148 such that the RXD signal represents the first CAN frame 148. The RXD signal can be sent from the first RXD interface 130 to the second RXD interface 218 of the CAN controller 114 via the signal connection 230.

[0044] Figure 4 An example of the first CAN frame 148 is schematically shown. Figure 4 The first CAN frame 148 shown in can be a CAN frame according to the CAN XL protocol. The first CAN frame 148 can include, for example: a start-of-frame SOF bit 164, an arbitration field 166, a control field 168, a data field 170, a cyclic redundancy check CRC field 172, an acknowledgment ACK field 174, and an end-of-frame EOF field 146. Other details regarding the structural design of CAN frames according to the CAN XL protocol can be learned from the associated standards.

[0045] If the first CAN frame 148 is configured according to the CAN XL protocol, the bits of the first CAN frame 148 can be transmitted at two different bit frequencies 236, 238. The bit frequency, specifically, one of the bit frequencies 236, 238, can be related to and / or be the reciprocal of the time (length) of the bit. For example, the SOF bit 164 and the bits of the arbitration field 166 can be transmitted at the first bit frequency 236. The bits of the control field 168, the bits of the data field 170, and the bits of the CRC field 172 can be transmitted at the second bit frequency 238. The second bit frequency 238 is preferably greater than the first bit frequency 236. The first bit frequency 236 can correspond to the bit frequency for transmitting the bits of a CAN frame according to the classical CAN protocol. In the example, the bits of the ACK field 174 and the bits of the EOF field 146 can be transmitted at the first bit frequency 236. From Figure 4 it can be seen that the EOF field 146 includes seven bits. The seven bits of the EOF field 146 are substantially each recessive bits.

[0046] Figure 5 Another example of the first CAN frame 148 is schematically shown. Figure 5 The first CAN frame 148 shown in can be a CAN frame 148 according to the classical CAN protocol. Also in this embodiment, the first CAN frame 148 can include, for example: a SOF bit 164, an arbitration field 166, a control field 168, a data field 170, a CRC field 172, an ACK field 174, and an EOF field 146. Other details regarding the structural design of the CAN frame 148 according to the classical CAN protocol can be learned from the associated standard. If the first CAN frame 148 is configured according to the classical CAN protocol, the bits of the first CAN frame 148 can be transmitted at the first bit frequency 236. From Figure 5 it can be seen that the EOF field 146 includes seven bits. The seven bits of the EOF field 146 are substantially each recessive bits.

[0047] In Figure 5 the example shown, the intermission ITM bit directly follows the EOF field 146. The ITM bit can form a so-called ITM field 150. In the example, the ITM field 150 includes three bits. The three bits of the ITM field 150 are substantially each recessive bits. Specifically, the ITM field 150 does not form part of the first CAN frame 148.

[0048] In Figure 5 the example shown, the inter-frame space IFS field 176 is directly adjacent to the ITM field 150. The IFS field 176 can represent an idle phase. The IFS field 176 can include any number N of bits, and each of the bits is substantially recessive. Specifically, the IFS field 176 does not form part of the first CAN frame 148.

[0049] In Figure 5 the example shown, a further first CAN frame 149 is adjacent to the IFS field 176. The further first CAN frame 149 is only partially and schematically shown in Figure 5 . The further first CAN frame 149 may be configured similarly to the first CAN frame 148.

[0050] Figure 1 FIG. schematically shows a CAN system 100. The CAN system 100 may include a plurality of CAN devices 102. Each CAN device 102 may be coupled to a CAN bus 104. To save electrical energy, the CAN controller 114 and / or the microcontroller 110 of the CAN device 102 may change from an active operating state to a deactivated state, also referred to as a sleep state. In the sleep state, the CAN controller 114 and / or the microcontroller 110 of the CAN device 102 consume less electrical energy than in the active operating state. To change back from the sleep state to the active operating state, the CAN controller 114 and / or the microcontroller 110 may be awakened by the CAN transceiver 120 of the associated CAN device 102. The awakening may be performed via a wake-up signal.

[0051] In the example, one of the CAN devices 102 of the CAN system 100 may be configured to generate a CAN bus signal representing a CAN frame 148 on the CAN bus 104. The CAN transceivers 120 of the other CAN devices 102 may receive the CAN frame 148 represented by the bus signal. In principle, each CAN transceiver 102 will be able to send a wake-up signal to the CAN controller 114 and / or the microcontroller 110 of the associated CAN device 102, respectively, in response to the received CAN frame 148 to cause a change from the sleep state to the active operating state. In the example, a first section 162 of the bus signal 142 representing a pattern 178, which is referred to as a predefined bit sequence, of the reference pattern 178 may be detected by each CAN transceiver 120. In response to detecting the reference pattern 178, each CAN transceiver 120 may send a wake-up signal to the CAN controller 114 and / or the microcontroller 110 of the respective associated CAN device 102.

[0052] By using the bits represented in the first section 162 at the start of the CAN frame, it can be found that the bits of the SOF bit 164 and the arbitration field 166 are used not only for a dedicated purpose but also for the purpose of the reference pattern 178.

[0053] It may be desirable not to wake up all CAN controllers 114 or microcontrollers 110 of all CAN devices 102, but rather only a predetermined group of CAN controllers 114 or microcontrollers 110 (of the respective associated device 102). In other words, it may be desirable to be able to specifically wake up a partial group of CAN devices 102 or associated CAN controllers 114 or microcontrollers 110.

[0054] As can be inferred from the following explanation, it is possible to integrate at least one wake-up pulse 152 in the silent section 144 of the bus signal 142, where the silent section 144 of the bus signal 142 represents the EOF field 146 and / or the ITM field 150. The wake-up pulse 152 can be integrated into the silent section 144 of the bus signal 142 in such a way that the wake-up pulse 152 is not evaluated by the receiver unit 136 of the CAN transceiver 120 as a representation of a dominant bit. In the silent section 144, only recessive bits should be represented by the bus signal 142. In short, the receiver unit 136 of the CAN transceiver 120 specifically checks in the silent section 144 whether the differential voltage of the silent section 144 of the bus signal 142 is less than a second threshold voltage TH2. The second threshold voltage TH2 can be between 0.5 V and 0.9 V. In an example, the second threshold voltage TH2 is 0.7 V. In the example, if the differential voltage of the silent section 144 of the bus signal 142 is less than the second threshold voltage TH2, the receiver unit 136 of the CAN transceiver 120 can detect the silent section 144 of the bus signal 142 as a plurality of recessive bits (of the EOF field 146 and / or the ITM field 150), even if at least one wake-up pulse 152 is included in the silent section 144 of the bus signal 142. Thus, at least one wake-up pulse 152 in the silent section 144 of the bus signal 142 can be invisible to the receiver unit 136 of the CAN transceiver 120. The wake-up pulse 152 can be detected only by a specific group of CAN transceivers 120 each including a wake-up unit 140.

[0055] Figure 2An example of a CAN transceiver 120 is schematically shown, where the CAN transceiver 120 includes a TXD interface 128, an RXD interface 130, a bus interface 132, a transmitter unit 138, and a receiver unit 136. The bus interface 132 is configured to receive a first differential voltage signal called a bus signal 142 from the CAN bus 104 via the bus interface 132. The CAN transceiver 120 further includes a wake-up unit 140. The wake-up unit 140 is preferably coupled to the bus interface 132. In the example, the wake-up unit 140 can receive the bus signal 142 via the bus interface 132. The wake-up unit 140 is configured to detect a silent section 144 of the bus signal 144. The silent section 144 of the bus signal 142 represents the EOF field 146 of the first CAN frame 148 and / or the ITM field 150 directly following the EOF field 146.

[0056] The wake-up unit 140 is configured to detect at least one wake-up pulse 152 including a differential bus voltage Vw1 less than a first predefined negative threshold voltage TH1 in the silent section 144 of the bus signal 142. The first threshold voltage TH1 can be between -0.2V and -0.45V. In the example, the first threshold voltage TH1 is -0.4V. The wake-up unit 140 is configured to send a wake-up signal in response to the detected at least one wake-up pulse 152. The wake-up signal can represent a wake-up command. The wake-up command can be used to wake up the CAN controller 114 and / or the microcontroller 110. In the example, the wake-up unit 140 can send the wake-up signal via another interface 220 of the CAN transceiver 120. This another interface 220 can be referred to as the first wake-up interface 220. In another example, the wake-up unit 140 can be configured to send the wake-up signal via the RXD interface 130 of the CAN transceiver 120. Figure 7 A corresponding embodiment of the CAN transceiver 120 is schematically shown. Hereinafter, again referring to Figure 2 the example in Figure 2 where the explanations related to Figure 7 can be similarly applied to

[0057] In the context of the foregoing explanation, it can be simply summarized as follows: The wake-up unit 140 detects the silent section 144 of the bus signal. If the wake-up unit 140 detects at least one wake-up pulse 152 in the silent section 144, the wake-up unit 140 will directly or indirectly send or cause to send a wake-up signal in response to the detection of at least one wake-up pulse 152. The wake-up signal is used to wake up the CAN controller 114 and / or the microcontroller 110, especially when the CAN transceiver 120 and the wake-up CAN controller 114 and / or the microcontroller 110 belong to the same CAN device 102. In an example, the CAN devices 102 of a selected group from a larger group including multiple CAN devices 102 may each include a wake-up unit 140. Thus, the CAN devices 102 of the selected group can form a partial network via the CAN bus 104, and the CAN controllers 114 and / or the microcontrollers 110 of the partial network can be woken up due to at least one wake-up pulse 152 incorporated in the silent section 144 of the bus signal. For other CAN devices 102 whose CAN transceivers 120 do not include the previously explained wake-up unit 140, at least one wake-up pulse 152 incorporated in the silent section 144 may be invisible.

[0058] In an example, a single wake-up pulse 152 can be understood as an embodiment of the wake-up mode 160. In another example, it can be understood that the wake-up mode 160 includes at least one wake-up pulse 152 or a plurality of wake-up pulses 152. Figure 3 Schematically shows a wake-up mode 160 that can be referred to as a first wake-up mode 194 in an example. The first wake-up mode 194 may exactly include two wake-up pulses 152. Each of the two wake-up pulses 152 can be incorporated into the silent section 144 of the bus signal 142, and the silent section 144 represents the EOF field 146 and / or the ITM field 150. In principle, the first wake-up mode 194 can also be designed differently, specifically, including more or fewer wake-up pulses 152.

[0059] Figure 6 Schematically shows another example of the bus signal 142. Figure 6 The bus signal 142 in Figure 3 is different from the bus signal 142 in Figure 6 in that different wake-up modes 160 are incorporated into the silent section 144 of the bus signal 142.

[0060] In an example, Figure 3 the bus signal 142 can represent a first CAN frame 148. In an example, the CAN frame 148 can be a CAN frame according to the CAN XL protocol. InFigure 4 An example of such a first CAN frame 148 is schematically shown in FIG. The bits of the data field 170 are represented by different pulses 240, 242 formed by the bus signal 142. Pulse 240 may also be referred to as the first data pulse 240. Pulse 242 may also be referred to as the second data pulse 242. In the example, the differential bus voltage of the first data pulse 240 may at least approximately correspond to the differential bus voltage Vw1 of the wake-up pulse 252, and / or vice versa. The differential bus voltage of the second data pulse 242 may be greater than the fourth threshold voltage TH4. In the example, the fourth threshold voltage TH4 is between -0.1V and 0.1V. For example, the fourth threshold voltage TH4 may be 0V.

[0061] Although the differential bus voltage of the first data pulse 240 may be approximately equal to the differential bus voltage VW1 of the wake-up pulse 152, the wake-up unit 140 will not detect or evaluate the first data pulse 240 as the wake-up pulse 152. In the example, the wake-up unit 140 is configured to detect at least one wake-up pulse 152 only in the silent section 144 of the bus signal 142. Thus, only the silent section 144 of the bus signal 142 is considered for the wake-up unit 140 to detect at least one wake-up pulse 142. Specifically, the wake-up unit 140 will thus not search for the wake-up pulse 152 in the data field 170 and will not be able to detect the wake-up pulse 152 in the data field 170. In other words, in the example, the wake-up unit 140 may be configured to monitor at least one wake-up pulse 142 only in the silent section 144 of the bus signal 142. Thereby, the wake-up unit 140 can robustly detect at least one wake-up pulse 152.

[0062] It has been previously explained that the differential bus voltage VW1 of the wake-up pulse 152 may be approximately equal to the differential bus voltage of the first data pulse 240. The differential bus voltage of the first data pulse 240 is selected such that as little electromagnetic interference as possible is caused on the CAN bus 104. Thus, the same advantage also applies to the wake-up pulse 152, which also causes low electromagnetic interference on the CAN bus 104. In the example, the differential bus voltage VW1 of the wake-up pulse 152 is between the first threshold voltage TH1 and the third predefined negative threshold voltage TH3. The third threshold voltage TH3 may be between -0.8V and -2V. Due to the voltage range between the first threshold voltage TH1 and the third threshold voltage TH3 of the differential bus voltage VW1 of the wake-up pulse 152, in the example, it is possible to achieve that no excessive electromagnetic interference is caused on the CAN bus 104.

[0063] Integrating at least one wake-up pulse 152 into the silent section 144 of the bus signal 142 may be specifically understood to mean that the silent section 144 of the bus signal 142 forms at least one wake-up pulse 152.

[0064] By integrating the at least one wake-up pulse 152 into the silent section 144 of the bus signal 142, the following effects and advantages can be achieved: No additional bandwidth for the at least one wake-up pulse 152 is required on the CAN bus 104. Thus, in the example, it is possible to integrate the at least one wake-up pulse into the silent section 144 of the bus signal 142 without disadvantaging the data transmission rate. As another advantage, integrating at least one wake-up pulse 152 into the silent section 144 prevents potential collisions with other frames and / or bus signals.

[0065] It has been previously explained that the wake-up unit 140 is configured to form a wake-up signal in response to detecting at least one detected wake-up pulse 152. In the example, the wake-up unit 140 may be coupled to the first wake-up interface 220 such that the wake-up unit 140 can send the wake-up signal via the first wake-up interface 220. In the example, the first wake-up interface 220 may be coupled to the second wake-up interface 222 of the CAN controller 114. In another example, the first wake-up interface 220 may be coupled to a power supply unit of the CAN device 102, for example, such that the power supply unit can be controlled by the wake-up unit 140 via the wake-up signal. In the example, the power supply unit of the device 102 may supply voltage to the microcontroller 110 and / or the CAN controller 114 in response to receiving the wake-up signal. By supplying the voltage, the microcontroller 110 and / or the CAN controller 114 can change from the deactivated state to the activated state.

[0066] In the example, the transceiver 120 is configured to change from the active (operating) state to the (deactivated) sleep state. The transceiver 120 can also change from the sleep state to the active operating state. The transceiver 120 can function fully in the operating state. The transceiver 120 can deactivate individual subunits in the sleep state. By deactivating the subunits of the transceiver 120, the transceiver 120 consumes less electrical energy. In the sleep state of the transceiver 120, the receiver unit 136 and / or the transmitter unit 138 can be deactivated. By deactivating the receiver unit 136, the power consumption of the transceiver 120 is reduced. By deactivating the transmitter unit 138, the power consumption of the transceiver 120 can also be reduced. In the sleep state of the transceiver 120, in the example, the receiver unit 136, the transmitter unit 138, and specifically other units of the transceiver 120 can be deactivated. This can further improve the savings in electrical energy during the sleep state. By deactivating the receiver unit 136, the receiver unit 136 cannot generate a signal at the first RXD interface 130 to wake up the CAN controller 114. Specifically, only when the transceiver 120 is in the operating state are the receiver unit 136 and / or the transmitter unit 138 of the transceiver 120 activated.

[0067] In the example, the transceiver 120 is configured such that the wake-up unit 140 is activated in the sleep state of the transceiver 120. In the active state of the wake-up unit 140, the wake-up unit 140 may perform, for example, the steps previously explained, such as detecting the silent section 144 of the bus signal 142, detecting the wake-up pulse 152 in the silent section 144, and / or forming a wake-up signal in response to detecting the wake-up pulse 152. The wake-up unit 140 that is active during the sleep state of the transceiver 120 provides the following advantages: the wake-up unit 140 can directly or indirectly wake up the CAN controller 114 and / or the microcontroller 110 via a wake-up command represented as a wake-up signal. Specifically, even if the receiver unit 136 and / or the transmitter unit 138 are deactivated in the sleep state of the transceiver 120, the wake-up unit 140 can be operationally active. In other words, the wake-up unit 140 can be used to monitor the bus signal 142 for the wake-up pulse 152 in the silent section 144 and, if necessary, wake up the CAN controller 114 and / or the microcontroller 110. The wake-up unit 140 can be configured such that the active wake-up unit 140 consumes less power than the activated receiver unit 136 and / or the activated transmitter unit 138. If the transceiver 120 is in the sleep state and the receiver unit 136 and / or the transmitter unit 138 are deactivated, power can be saved despite the activation of the wake-up unit 140 without sacrificing the ability to wake up the CAN controller 114 and / or the microcontroller 110.

[0068] In the example, the wake-up unit 140 may be coupled to the receiver unit 136 and / or the transmitter unit 138. The wake-up unit 140 can be configured to directly or indirectly control the receiver unit 136 and / or the transmitter unit 138 in response to detecting the wake-up pulse 152 such that the receiver unit 136 and / or the transmitter unit 138 are activated. In the example, the wake-up unit 140 may be coupled to the receiver unit 136 and / or the transmitter unit 138 such that the wake-up unit 140 can send an activation signal representing an activation command to the receiver unit 136 and / or the transmitter unit 138. The receiver unit 136 and / or the transmitter unit 138 can each be configured to be activated in response to receiving the activation signal. In the example, the transceiver 120 may include a main unit 210, where the main unit 210 includes the receiver unit 136 and / or the transmitter unit 138. In the example, the main unit 210 can be activated or deactivated. The wake-up unit 140 can be coupled to the main unit 210 to send the activation signal to the main unit 210. The main unit 210 can be configured to supply an operating voltage to the receiver unit 136 and / or the transmitter unit 138 in response to receiving the activation signal. By supplying the operating voltage, the receiver unit 136 and / or the transmitter unit 138 can be activated.

[0069] Figure 3An example of the bus signal 142 is schematically shown. Below the bus signal 142, Figure 3 An example of the first CAN frame 148 is schematically shown. As indicated by a number of vertical dashes, a section of the bus signal 142 can be assigned to one or more fields of the first CAN frame 148. The corresponding section of the bus signal can represent the bits of the correspondingly assigned field. At this time, it should be noted again that the bus signal is only schematically shown in Figure 3 and specifically, Figure 3 not all parts of the bus signal 142 are shown in

[0070] In the example, the silent section 144 of the bus signal can represent only the combination of the EOF field 146 and the ITM field 150, or only the EOF field 146 or only the ITM field 150. In the example, the silent section 144 of the bus signal 142 can represent only the EOF field 146 or only the ITM field 150. Figure 3 Another example is schematically shown, in which the silent section 144 of the bus signal 142 represents only the combination of the EOF field 146 and the ITM field 150 directly following the EOF field 146. The EOF field 146 can include 7 bits of the first CAN frame 148, specifically, exactly 7 bits. The ITM field 150 can include 3 bits, specifically, exactly 3 bits. The ITM field 150 can directly follow the EOF field 146. In the example, the ITM field 180 does not form part of the first CAN frame 148.

[0071] In the example, the so-called inter-frame space IFS176 can be directly adjacent to the ITM field 150. The inter-frame space 176 can extend from the ITM field 150 to another first CAN frame 149. The inter-frame space 176 can be represented by the bus signal 142. During the inter-frame space 176, the bus voltage of the bus signal 142 can be at least substantially 0V. In this context, it can be assumed in the example that the inter-frame space 176 includes one recessive bit or more recessive bits. In the example, the silent section 144 of the bus signal 142 represents the EOF field 146, the ITM field 150 following the EOF field 146, and / or the inter-frame space 176 following the ITM field 150.

[0072] As in Figure 3As can be seen in the example of the signal waveform of the bus signal 142, the silent section 144 of the bus signal 142 can directly follow the trigger pulse 154 of the bus signal 142. The trigger pulse voltage VG of the trigger pulse 154 is preferably greater than the second threshold voltage TH2. The bus voltage in the silent section 144 of the bus signal 142 is always less than the second threshold voltage TH2. When transitioning from the trigger pulse 154 to the silent section 144, there may be a short oscillation of the bus voltage, specifically an undershoot. In the example, it should be assumed that the short oscillation only occurs during the waiting time TW, which directly follows the trigger pulse 154. The base section 156 of the bus signal 142 can directly follow the waiting time TW. The bus voltage of the base section 156 of the bus signal 142 can be at least substantially 0V. The observation section 158 of the bus signal 142 can directly follow the base section 156. The base section 156 and the subsequent observation section 158 can each form a part of the silent section 144 of the bus signal 142. In the example, the silent section 144 of the bus signal 142 is formed by the base section 156 and the subsequent observation section 158. In another example, the silent section 144 can also include the section of the bus signal 142 during the waiting time TW.

[0073] Figure 8 An example of a flowchart schematically showing the transceiver 120 is presented. If the transceiver 120 is in the sleep state, the receiver unit 136 and / or the transmitter unit 138 can be deactivated. During the sleep state of the transceiver 120, the wake-up unit 140 can be active. The wake-up unit 140 can be coupled to the bus interface 132 such that the bus signal 142 can be received by the wake-up unit 140 via the bus interface 132. The wake-up unit 140 can be configured to detect the trigger pulse 154 based on the bus signal 142, where the trigger pulse 154 includes a differential bus voltage VG of the bus signal 142 that is greater than the second threshold voltage TH2. The trigger pulse 154 can have a duration of, for example, at least 0.5 μs to 5 μs. The second threshold voltage TH2 is a predefined positive threshold voltage. In the example, the second threshold voltage TH2 can be between +0.5V and +0.9V. In the example, the second threshold voltage TH2 can be +0.9V.

[0074] from Figure 3 The example of the bus signal 142 schematically shows that the bus signal 142 can theoretically include multiple trigger pulses 154. Therefore, the trigger pulse 154 alone cannot be used to robustly detect the subsequent silent section 144. Based on Figure 8An example flow chart, after the detection of the trigger pulse 154, there may be a waiting time TW. The wake-up unit 140 may be configured to wait for the waiting time TW following the trigger pulse 154. The waiting time TW may be a predefined time. In the example, the waiting time TW may be between 0.01 μs and 2 μs, specifically between 0.1 μs and 1.3 μs. During the waiting time TW, oscillation of the bus signal 142 may occur, and the oscillation may be ignored by the wake-up unit 140, especially in the case where the oscillation involves an undershoot. Ignoring the possible oscillation of the bus signal 142 during the waiting time TW improves the robustness of detecting the wake-up pulse 152.

[0075] Based on Figure 8 An example of a flow chart, after waiting for the waiting time TW, an inspection may be performed to determine whether a base section 156 of the bus signal 142 follows after the waiting time TW. In the example, the wake-up unit 140 may be configured to detect the base section 156 of the bus signal 142 based on the bus signal 142. The base section 156 includes a differential bus voltage between a first threshold voltage TH1 and a second threshold voltage TH2 during a predefined base time TA. The base time TA directly follows the waiting time TW. If the base section 156 actually follows after the waiting time TW, the differential bus voltage of the base section 156 is neither less than the first threshold voltage TH1 nor greater than the second threshold voltage TH2. Thus, it can be determined through the base section 156 that neither a pulse corresponding to the trigger pulse 154 nor a pulse corresponding to the wake-up pulse 152 has occurred in the base section 156. Therefore, the first data pulse 240 may not have occurred in the base section 156.

[0076] The basic section 156 lasts for a predefined basic time TA. In an example, the basic time TA can be between 2 μs and 7 μs. In another example, the basic time TA can be predefined relative to the bit frequency 236 of the bits for transmitting the SOF bit 164, the arbitration field 166, the ACK field 174, and / or the EOF field 146. In an example, the basic time TA can be two to seven times the cycle time according to the aforementioned bit frequency 236. If the first CAN frame 148 is configured as a CAN frame according to the CAN XL standard, the bits of the data field 170 can be represented by the first data pulse 240 and the second data pulse 242 of the bus signal 142. According to the CAN XL standard, the so-called stuffing bits are executed at the latest after ten equal (first or second) data pulses 240, 242. In an example, ten consecutive second data pulses 242 are followed by a first data pulse 240, and the first data pulse 240 represents a stuffing bit in this example. The time TP of ten consecutive second data pulses 242 is ten times the simple cycle time according to the second bit frequency 238. In an example, the time TP can be about 1.25 μs. Thus, the first data pulse 240 is generated at the latest 1.25 μs after the transmission of the bits of the data field 170, and the differential bus voltage of the first data pulse 240 is less than the first threshold voltage TH1. In this context, the predefined basic time TA should be considered again. During the basic time TA, the basic section 156 of the bus signal 142 includes a differential bus voltage that is neither less than the first threshold voltage TH1 nor greater than the second threshold voltage TH2. For example, the basic time TA can be between 2 μs and 7 μs. Thus, it can be determined that the transmission of the bits of the data field 170 is not performed during the basic time TA. As another effect, it can be determined that no second data pulse 242 occurs during the basic time TA.

[0077] In the previous two paragraphs, it is thus determined that no trigger pulse 154, no wake-up pulse 152, no first data pulse 240, and no second data pulse 242 occur in the basic section 156 that lasts for the basic time TA. As another effect, it can be noted that the potential observation section 158 that may follow the basic section 156 of the bus signal 142 may not be used to represent the bits of the data field 170.

[0078] Based on Figure 8 the example flowchart, after the wake-up unit 140 detects the basic section 156, a check can be performed to determine whether the observation section 158 follows the basic section 156. In the case where the wake-up unit 140 does not detect the basic section 156, the wake-up unit 140 can abort the check.

[0079] In the example, the wake-up unit 140 is configured to detect the observation section 158 based on the bus signal 142. The observation section 158 includes a differential bus voltage that is less than a second threshold voltage TH2 during a predefined observation time T0. The observation time T0 directly follows the base time TA. If the observation section 158 actually follows the base section 156, the differential bus voltage of the observation section 158 is always less than the second threshold voltage TH2. In the example, the observation time T0 can be between 5 μs and 7 μs. In another example, the observation time T0 can be predefined relative to a first bit frequency 236 for transmitting bits of the SOF bit 164, arbitration field 166, ACK field 174, and / or EOF field 146. In the example, the observation time T0 can be five to seven times the cycle time according to the first bit frequency 236. In another example, the base time TA and the observation time T0 can be a total of eleven times the cycle time of the first bit frequency 236. Thus, it can be assumed that bits in the following fields or bits of the first CAN frame 148 are not represented in the base section 156 and the subsequent observation section 158: SOF 164, arbitration field 166, control field 168, data field 170, CRC field 172, ACK field 174.

[0080] During the base time TA and the observation time T0, the bus signal 142 includes a differential bus voltage that is always less than the second threshold voltage TH2. The base section 156 and the observation section 158 can form a silent section 144. The silent section 144 can also include a section of the bus signal 142 during a waiting period TW. In view of the foregoing explanation, it can thus be noted that the silent section 144 can represent the EOF field 146 and / or the ITM field 150. The wake-up pulses 152 that can be included in the observation section 158 of the bus signal 142 are invisible to a known transceiver 120 and / or the receiver unit 136. However, this invisibility does not apply to the wake-up unit 140. The wake-up unit 140 is configured to detect at least one wake-up pulse 152 in the observation section 158 of the bus signal 142. Each wake-up pulse 152 includes a differential bus voltage that is less than a first threshold voltage TH1. Each wake-up pulse 152 can include a time between 0.01 μs and 10 μs. Specifically, if each wake-up pulse 152 includes a time that is less than the cycle time of the first bit frequency 236, a plurality of wake-up pulses 152 can be included in the observation section 158. In the example, each wake-up pulse 152 can include a time between 0.05 μs and 5 μs, specifically between 0.05 μs and 3 μs.

[0081] Based on Figure 8An example of a flowchart, after detecting at least one wake-up pulse 152, a wake-up signal can be formed (specifically, generated) by the wake-up unit 140. In the case where the wake-up unit 140 does not detect a wake-up pulse 152 in the observation section 158, the wake-up unit 140 can terminate the check.

[0082] In the example, the wake-up unit 140 is configured to detect a predefined wake-up pattern 160 in the silent section 144, specifically in the observation section 158. In the example, the wake-up pattern 160 can be Figure 3 the first wake-up pattern 194 schematically shown in Figure 6 In another example, the wake-up pattern 160 can be

[0083] The wake-up pattern 160 can include multiple wake-up pulses 152. In the example, the wake-up pattern 160 can include at least two, three, five, or ten wake-up pulses 152. For each wake-up pulse 152 of the wake-up pattern 160, it can refer to the foregoing explanations, preferred features, technical effects, and advantages in a similar manner as previously described for the wake-up pulse 152. For example, each wake-up pulse 152 of the wake-up pattern 160 includes a differential bus voltage VW1 less than the first threshold voltage TH1. The multiple wake-up pulses 152 of the wake-up pattern 160 can each be separated by a signal section 224 called a separation section 224 in the bus signal 142, in which the differential bus voltage is greater than the first threshold voltage TH1 and less than the second threshold voltage TH2. The differential bus voltage of each separation section 224 can be approximately 0V. In the example, the wake-up pulses 152 of the wake-up pattern 160 are not directly arranged continuously. Each separation section 224 can also form a part of the wake-up pattern 160. In the example, the wake-up pattern 160 is formed by multiple wake-up pulses 152 and multiple separation sections 244.

[0084] It has been previously explained that the wake-up unit 140 can be configured to form a wake-up signal in response to detecting at least one wake-up pulse 152. In the example, the wake-up unit 140 is configured such that a single wake-up pulse 152 is not sufficient to form a wake-up signal. In the example, the wake-up unit 140 can be configured to send the wake-up signal via the interface of the transceiver 120 in response to detecting the wake-up pattern 160.

[0085] In the example, the wake-up unit 140 can be coupled to the first wake-up interface 220. In this case, the wake-up unit 140 can generate a wake-up signal and send the wake-up signal via the first wake-up interface 220. In another example, the wake-up unit 140 can be coupled to the RXD interface 130. Figure 7An example of the transceiver 120 is schematically shown, where the wake-up unit 140 is coupled to the RXD interface 130. In this case, the wake-up unit 140 can generate a wake-up signal and send the wake-up signal via the RXD interface 130. In another example, the wake-up unit 140 can be directly or indirectly coupled to the receiver unit 136. In the example, the wake-up unit 140 can control the receiver unit 136 such that the wake-up signal is sent from the receiver unit 136 via the RXD interface 130. Thus, the wake-up unit 140 causes the receiver unit 136 to send a wake-up signal. However, the sending is caused by the control of the receiver unit 136 by the wake-up unit 140.

[0086] If the CAN transceiver 120 is configured according to the CAN XL standard, the receiver unit 136 can be configured to detect the bits of the SOF bit 164, the arbitration field 166, the bits of the ACK field 174, and the bits of the EOF field 146 only according to whether the bus voltage of the bus signal 142 representing the corresponding bits is greater than the second threshold voltage TH2 or less than the second threshold voltage TH2. If the bus voltage is greater than the second threshold voltage TH2, the receiver unit 136 evaluates the bus voltage as a representation of a dominant bit. If the bus voltage is less than the second threshold voltage TH2, the receiver unit 136 evaluates the bus voltage as a representation of a recessive bit. The wake-up pulse 152 integrated into the silent section 144 of the bus signal 142 includes a bus voltage less than the first threshold voltage TH1. The first threshold voltage TH1 is less than the second threshold voltage TH2. The silent section 144 can represent at least one section of the EOF field 146. If the wake-up pulse 152 occurs while the bus signal 142 represents at least one section of the EOF field 146, the receiver unit 136 will determine that the bus voltage of the bus signal is less than the second threshold voltage TH2. Thereby, the receiver unit 136 will evaluate the wake-up pulse 152 as a representation of a recessive bit. As another effect, integrating at least one wake-up pulse 152 into the silent section 144 of the bus signal 142 remains invisible to the receiver unit 136. The previous explanation particularly applies to the case where the silent section 144 of the bus signal 142 is received by the receiver unit 136 that is activated rather than deactivated. If the receiver unit 136 is deactivated, it can be stipulated that the receiver unit 136 does not evaluate the silent section 144 of the bus signal 142.

[0087] If the receiver unit 136 is activated, the receiver unit 136 can be configured to generate an RXD signal at the first RXD interface 130 based on the bus signal 142 representing the first CAN frame 148 such that the RXD signal represents the first CAN frame 148. The wake-up unit 140 can be configured to control the receiver unit 136 such that a wake-up pulse 152 incorporated in a silent section 144 representing an EOF field 146 in the bus signal 142 is evaluated by the receiver unit 136 as a recessive bit and / or represented as a recessive bit by the RXD signal. Thereby, this can prevent at least one wake-up pulse 152 from generating an error signal at the RXD interface 130 and / or the bus interface 132.

[0088] In another example, the wake-up unit 140 can be configured to detect a first section 162 in the bus signal 142 representing a SOF bit 164 and / or an arbitration field 166. In the example, the wake-up unit 140 can be configured to detect a predefined reference pattern 178 represented as the first section 162 of the bus signal 142. The reference pattern 178 should not be confused with and is different from the previously explained wake-up pattern 152. The reference pattern 178 does not include a voltage less than a first threshold voltage TH1. Detecting the reference pattern 178 can be used, for example, as a flowchart according to Figure 8 to start checking the preconditions for the wake-up pattern 152. Thus, the wake-up unit 140 can be configured to perform the detection of the wake-up pulse 152 and / or the formation of the wake-up signal only when the reference pattern 178 has been previously detected. This can improve the robustness of detecting the wake-up pattern 152 against possible interference signals on the CAN bus 104.

[0089] Previously, it has been explained that the wake-up unit 140 is configured to send a wake-up signal via an interface specifically the first wake-up interface 220 in response to detecting at least one wake-up pulse 152. The first wake-up interface 220 can be coupled to a second wake-up interface 222 of the CAN controller 114. The CAN controller 114 can be configured to change from an inactive state to an active operating state in response to the received wake-up signal. In one example, also as Figure 2 schematically shown in, the CAN device 102 includes a CAN transceiver 120 and a CAN controller 114. In the example, the CAN device 102 can include a microcontroller 110, where the CAN controller 114 can be implemented by the microcontroller 110.

[0090] Figure 1An example of a CAN system 100 is schematically shown. The system 100 may include a plurality of CAN devices 102 coupled via a CAN bus 104. One of the CAN devices 102 may form a bus signal 142 on the CAN bus 104. The bus signal 142 may be received by other CAN devices 102. If one of the CAN devices 102 that receives the bus signal 142 includes a CAN transceiver 120 that includes a wake-up unit 140, the CAN controller 114 of the same CAN device 102 may be woken up by a wake-up signal formed by the wake-up unit 140. However, this requires at least one wake-up pulse 152 to be integrated into the silent section 144 of the bus signal 142. Therefore, the CAN transceiver 120 of the CAN device 102 that forms the bus signal 142 on the CAN bus 104 should have the ability to integrate the at least one wake-up pulse 152 into the silent section 144 of the bus signal 142.

[0091] The following relates to aspects of how the CAN transceiver 120 can integrate the wake-up pulse 152 into the silent section 144 of the bus signal 142. In an example, if the CAN transceiver 120 is activated, the CAN transceiver 120 may be configured to receive a control command via an interface of the CAN transceiver 120 other than the bus interface 132. The control command may indicate to send and / or integrate the wake-up pulse 152 into the bus signal 142. The CAN transceiver 120 may be activated if the transmitter unit 138 and / or the receiver unit 136 is activated. Another interface of the CAN transceiver 120 may be referred to as a first control interface 224. The first control interface 224 may be different from the first TXD interface 128 and / or the first RXD interface 130 and / or the first wake-up interface 220. The first control interface 224 may be coupled via a signal connection to a second control interface 226. The CAN controller 114 may be configured to generate a control command. In an example, the CAN controller 114 may send a control signal from the second control interface 226 to the first control interface 224, where the control signal represents the control command.

[0092] In an example, the CAN transceiver 120 can be configured to receive a TXD signal representing a CAN frame via a first TXD interface 128. This CAN frame is referred to as a second CAN frame. The TXD signal and / or the second CAN frame do not represent at least one wake-up pulse 158. The CAN transceiver 120 can be configured to generate a bus signal 142 at a CAN bus interface 132 such that the bus signal 142 represents the second CAN frame. However, in response to receiving a control command, the CAN transceiver 120 adjusts the bus signal 142 such that a silent section 144 of an EOF field 146 and / or an ITM field immediately following the second CAN frame represented in the bus signal 142 includes at least one wake-up pulse 152. The bus signal 142 is sent from another CAN transceiver 120 to the CAN transceiver 120 of other CAN devices 102 via a CAN bus 104. If at least one of the CAN transceivers 120 receiving the bus signal 142 includes a wake-up unit 140, the corresponding wake-up unit 140 can detect the wake-up pulse 152. The CAN transceiver 120 receiving the bus signal 142 can be regarded as receiving the bus signal 142 representing a first CAN frame 148. In this case, the second CAN frame can correspond to the first CAN frame.

[0093] has been incorporated Figure 3 and 6 explains that several different wake-up modes 194, 196 can be used. Different wake-up modes 194, 196 can be used to form different partial networks in the CAN system 100.

[0094] Figure 1 An example of the CAN system 100 is schematically shown. The CAN system 100 includes a plurality of CAN devices 102. Each CAN device 102 includes a CAN transceiver 120. One of the plurality of CAN transceivers 120 can be referred to as a first CAN transceiver 186. Another CAN transceiver 120 among the plurality of CAN transceivers 120 can be referred to as a second CAN transceiver 188. The CAN device 102 including the first CAN transceiver 186 can be referred to as a first CAN device 198. The CAN device 102 including the second CAN transceiver 188 can be referred to as a second CAN device 200.

[0095] In an example, the wake-up unit 140 of the first CAN transceiver 186 is configured to be able to detect a first wake-up mode 194 as a wake-up mode 160. The wake-up unit 140 of the first CAN transceiver 186 can be further configured not to detect a second wake-up mode 196 as a wake-up mode 160, and / or to be able to specifically detect the first wake-up mode 194 as a wake-up mode 160.

[0096] In an example, the wake-up unit 140 of the second CAN transceiver 188 is configured to be able to detect a second wake-up mode 196 as a wake-up mode 160. The second wake-up mode 196 is different from the first wake-up mode 194. The wake-up unit 140 of the second CAN transceiver 188 may alternatively be configured not to detect the first wake-up mode 194 as a wake-up mode 160, and / or to be able to specifically detect the second wake-up mode 196 as a wake-up mode 160.

[0097] In this context, the CAN system 100 may include a CAN bus 104, at least one first CAN transceiver 186, and at least one second CAN transceiver 188. In another example, the CAN system 100 may include a CAN bus 104, at least one first CAN device 198 including a first CAN transceiver 186, and at least one second CAN device 200 including a second CAN transceiver 188. The CAN system 100 may preferably include a plurality of first CAN devices 198 and a plurality of second CAN devices 200. The plurality of first CAN devices 198 may form a first partial network via the CAN bus 104. The plurality of second CAN devices 200 may form a second partial network via the CAN bus 104.

[0098] Figure 9 An example of a flowchart schematically showing the method 202 is shown. Specifically, the method 202 is for the CAN transceiver 120. The method 202 may include the following steps:

[0099] a) Receiving, at the bus interface 132, a first differential voltage signal called a bus signal 142,

[0100] b) The wake-up unit 140 detecting an end-of-frame EOF field 146 of a CAN frame 148 represented in the bus signal 142 and / or a silent section 144 of an intermission space ITM 150 following the EOF field 146 based on the bus signal 142,

[0101] c) The wake-up unit 140 detecting, in the silent section 144 of the bus signal 142, at least one wake-up pulse 152 having a differential bus voltage less than a first predefined negative threshold voltage TH1, and

[0102] d) The wake-up unit 140 causing a wake-up signal representing a wake-up instruction to be sent via an interface of the transceiver in response to the detected at least one wake-up pulse 152, the interface being specifically the RXD interface 130 or another interface 220 of the transceiver 120.

[0103] For the method 202, reference is made to the previously explained, preferred features, technical effects, and advantages in a manner similar to that previously explained in connection with the CAN transceiver 120, the CAN device 102, and / or the CAN system 100.

[0104] Although the described exemplary embodiments disclosed herein focus on devices, systems, and methods of using the same, the present disclosure is not necessarily limited to the example embodiments shown herein.

[0105] The systems and methods described herein may be embodied, at least in part, by a computer program or multiple computer programs, which may exist in a single computer system or across multiple computer systems in a variety of forms, both in use and in standby. For example, these computer programs may exist as software programs in source code, object code, executable code, or other formats consisting of program instructions for performing some steps. Any of the above formats may be implemented in compressed or uncompressed form on a computer-readable medium that may include storage devices and signals.

[0106] As used herein, the term "computer" refers to any electronic device that includes a processor, such as a general-purpose central processing unit (CPU), a special-purpose processor, or a microcontroller. A computer is capable of receiving data (input), performing a series of predetermined operations on the data, and generating results therefrom in the form of information or signals (output). Depending on the context, the term "computer" will refer specifically to a processor or more generally to a processor associated with a collection of related elements contained within a single housing or enclosure.

[0107] The term "processor" or "processing unit" refers to a data processing circuit, which may be a microprocessor, a coprocessor, a microcontroller, a microcomputer, a central processing unit, a field programmable gate array (FPGA), a programmable logic circuit, and / or any circuit that manipulates signals (analog or digital) based on operating instructions stored in a memory. The term "memory" refers to a storage circuit or multiple storage circuits, such as a read-only memory, a random access memory, a volatile memory, a non-volatile memory, a static memory, a dynamic memory, a flash memory, a cache memory, and / or any circuit that stores digital information.

[0108] As used herein, a "computer-readable medium" or "storage medium" may be any component that can contain, store, communicate, propagate, or transport a computer program for use by or in conjunction with an instruction execution system, device, or apparatus. A computer-readable medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, apparatus, or propagation medium. More specific examples of computer-readable media (a non-exhaustive list) may include the following: an electrical connection with one or more wires, a portable computer disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disc read-only memory (CDROM), a digital versatile disc (DVD), a Blu-ray disc (BD), and a memory card.

[0109] It should be noted that the above embodiments have been described with reference to different topics. Specifically, some embodiments may be described with reference to method - type claims, while other embodiments may be described with reference to apparatus - type claims. However, those skilled in the art should understand from the above that, unless otherwise specified, any combination of features related to different topics (specifically, the combination of features of method - type claims and features of apparatus - type claims), in addition to any combination of features belonging to one type of topic, is also considered to be disclosed together with this document.

[0110] In addition, it should be noted that the drawings are schematic. In different figures, like or identical elements are denoted by the same reference numerals. Furthermore, it should be noted that, in an effort to provide a concise description of the illustrative embodiments, details of implementations that are part of the routine practice of those skilled in the art may not be described. It should be understood that in the development of any such implementation, as in any engineering or design project, numerous implementation - specific decisions must be made to achieve the developer's specific goals, such as compliance with system - related and business - related constraints, which may vary between different implementations. In addition, it should be understood that such development work may be complex and time - consuming, but is nevertheless a routine task for those skilled in the art in design, fabrication, and production.

[0111] Finally, it should be noted that those skilled in the art should be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference numerals placed in parentheses shall not be construed as limiting the claims. The word "comprising" does not exclude the presence of other elements or steps than those listed in the claims. The word "a" preceding an element does not exclude the presence of a plurality of such elements. The measures recited in the claims can be implemented by means of hardware including several different elements and / or by means of a suitably programmed processor. In apparatus claims listing several components, several of these components may be embodied by the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0112] Unless otherwise stated, terms such as "first" and "second" are used arbitrarily to distinguish the elements described by such terms. Therefore, these terms are not necessarily intended to indicate a temporal or other prioritization of such elements.

Claims

1. A controller area network (CAN) transceiver, characterized in that: include: Send data TXD interface, Receive data RXD interface, bus interface for coupling to the CAN bus, Receiver unit, transmitter unit, and Wake-up unit, wherein the bus interface is configured to receive a first differential voltage signal, referred to as a bus signal, from the CAN bus via the bus interface, The wake-up unit is configured to detect an EOF field indicating an end of frame of a first CAN frame in the bus signal and / or a silent section based on an intermittent space ITM following the EOF field in the bus signal, wherein the wake-up unit is configured to detect at least one wake-up pulse having a differential bus voltage less than a first predefined negative threshold voltage in the silent section of the bus signal, and The wake-up unit is configured to send a wake-up signal representing a wake-up instruction via an interface of the transceiver in response to the at least one detected wake-up pulse, the interface being specifically the RXD interface or another interface of the transceiver.

2. A CAN transceiver according to the preceding claim, characterised in that The wake-up unit is configured to detect a trigger pulse based on the bus signal, the trigger pulse having a differential bus voltage greater than a positive predefined second threshold voltage, wherein the wake-up unit is configured to wait for a predefined waiting time after the trigger pulse, wherein the wake-up unit is configured to detect a base segment of the bus signal based on the bus signal, wherein during the predefined base time after the waiting time, the base segment has a differential bus voltage between a first threshold voltage and the second threshold voltage, wherein the wake-up unit is configured to detect an observation segment of the bus signal based on the bus signal, wherein during the predefined observation time after the base time, the observation segment has a differential bus voltage less than the second threshold voltage, wherein the observation segment forms at least a part of the silent segment, and wherein the wake-up unit is configured to detect at least one wake-up pulse having a differential bus voltage less than the first threshold voltage in the observation segment of the bus signal.

3. A CAN transceiver according to the preceding claim, characterized in that The waiting time is between 0.01 μs and 2 μs, specifically between 0.1 μs and 1.3 μs, and / or wherein the base time is between 2 and 7 times the cycle time according to a predefined bit frequency at the bus interface, and / or wherein the observation time is between 5 and 7 times the cycle time according to the predefined bit frequency at the bus interface.

4. The CAN transceiver according to any one of the preceding claims 3 to 4, characterized in that: The second threshold voltage is between positive 0.5 volts and positive 0.9 volts.

5. A CAN transceiver according to any preceding claim, characterized in that The first threshold voltage is between negative 0.25 volts and negative 0.45 volts.

6. A CAN transceiver according to any preceding claim, characterised in that The wake-up unit is configured to detect a predefined wake-up pattern in the silent section, the predefined wake-up pattern comprising a plurality of wake-up pulses, each wake-up pulse having a differential bus voltage less than the first predefined negative threshold voltage, and wherein the wake-up unit is configured to cause the wake-up signal representing a wake-up instruction to be sent specifically via the RXD interface or another interface of the transceiver in response to the detected wake-up pattern.

7. A CAN transceiver according to any preceding claim, characterised in that The CAN transceiver and / or the receiver unit is configured to interpret the wake-up pulse as a recessive bit.

8. A CAN device, characterized in that: include: A CAN transceiver according to any preceding claim, and CAN controller, wherein the CAN controller is coupled to the TXD interface of the CAN transceiver and the RXD interface of the CAN transceiver, wherein the wake-up unit of the CAN transceiver is configured to send the wake-up signal to the CAN controller via the RXD interface or another interface of the CAN transceiver in response to a detected wake-up pulse or a detected wake-up pattern, and Wherein the CAN controller is configured to change from an inactive state to an operational state in response to a received wake-up signal.

9. A CAN system, characterized in that: include: CAN bus, The first CAN transceiver according to claim 7, and The second CAN transceiver according to claim 7, wherein the wake-up unit of the first CAN transceiver is configured to detect a first wake-up pattern as a wake-up pattern, wherein the wake-up unit of the second CAN transceiver is configured to detect a second wake-up pattern as another wake-up pattern, and The first wake-up mode and the second wake-up mode are different.

10. A method for a CAN transceiver, characterized in that, The CAN transceiver comprises a transmit data TXD interface, a receive data RXD interface, a bus interface for coupling to a CAN bus, a receiver unit, a transmitter unit and a wake-up unit, wherein the method comprises the following steps: a) receiving at said bus interface a first differential voltage signal, referred to as a bus signal, b) the wake-up unit detects an EOF field indicating an end of frame of a CAN frame in the bus signal and / or a silent section based on an intermittent space ITM following the EOF field in the bus signal, c) the wake-up unit detects at least one wake-up pulse having a differential bus voltage less than a first predefined negative threshold voltage in the silent section of the bus signal, and d) The wake-up unit sends a wake-up signal indicating a wake-up instruction via an interface of the transceiver in response to the detected at least one wake-up pulse, the interface being specifically the RXD interface or another interface of the transceiver.

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