Controller area network communication circuit, system, circuit board and electronic equipment

Abstract

The utility model discloses a controller local area network communication circuit and system, a circuit board and electronic equipment, and relates to the technical field of communication, and the controller local area network communication circuit comprises a controller local area network bus; a plurality of acquisition control units, wherein each acquisition control unit comprises a first receiving end and a first transmitting end; the diode unit comprises a plurality of first switching diodes, the plurality of first switching diodes are in one-to-one correspondence with the plurality of acquisition control units, the first sending ends of the acquisition control units are electrically connected with the negative electrode ends of the corresponding first switching diodes, and the positive electrode ends of the first switching diodes are electrically connected with the controller local area network bus; the first switching diode is used for limiting interference of an external circuit on the acquisition control unit; and the voltage pull-up unit is electrically connected with the controller local area network bus, through the controller local area network communication circuit provided by the invention, the simplification of the controller local area network communication circuit is promoted by deleting the use of a transceiver chip, and the production cost is reduced.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a controller area network communication circuit, system, circuit board, and electronic equipment. Background Art

[0002] Traditional controller area network communication circuits are usually used for external communications. Therefore, in order to improve the long-distance transmission capability and anti-interference capability of the controller area network communication circuit during external communications, the existing technology often uses transceiver chips to achieve the above-mentioned capability improvements. In addition to external communications, the controller area network communication circuit can also be used for internal communications, but internal communications do not require long-distance transmission, and the interference factor is also less than that of external communications. Therefore, when traditional controller area network communication circuits are used for internal communications, complex lines and waste of resources will occur. Utility Model Content

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a controller area network communication circuit that can be used for internal communication without using a transceiver chip, has a simple circuit, and can save costs.

[0004] The present application also proposes a circuit board having the above-mentioned controller area network communication circuit.

[0005] The present application also proposes a system having the above circuit board.

[0006] The application also proposes an electronic device having the above system.

[0007] According to the first aspect of the present application, a controller area network communication circuit includes:

[0008] Controller Area Network bus;

[0009] A plurality of acquisition control units, each of which includes a first receiving end and a first transmitting end;

[0010] a diode unit, wherein the diode comprises a plurality of first switch diodes, wherein the plurality of first switch diodes correspond one-to-one to the plurality of acquisition control units, wherein the first transmitting end of the acquisition control unit is electrically connected to the cathode end of the corresponding first switch diode, and the anode end of the first switch diode is electrically connected to the controller area network bus, and the first switch diode is used to limit interference of an external circuit on the acquisition control unit;

[0011] A voltage pull-up unit is electrically connected to the controller area network bus and is used to output a high level voltage to the controller area network bus.

[0012] According to the controller area network communication circuit of the embodiment of the present application, there are at least the following beneficial effects: by eliminating the use of transceiver chips, the circuit of the controller area network communication circuit is simplified and the production cost is reduced, so that the controller area network communication circuit can be more suitable for internal communication; by arranging the first switch diode between the acquisition control unit and the controller area network bus, the interference of the external circuit to the acquisition control unit can be avoided, and the probability of risk is reduced; by setting the voltage pull-up unit, the voltage pull-up unit can be prompted to transmit a high-level voltage to the controller area network bus, thereby maintaining the controller area network bus in a high-level state when idle.

[0013] According to some embodiments of the present application, a data concentration processing unit is further included, the diode unit also includes a second switching diode, the data concentration processing unit includes a second receiving end and a second transmitting end, the second receiving end of the data concentration processing unit is electrically connected to the controller local area network bus, the second transmitting end of the data concentration processing unit is electrically connected to the cathode end of the second switching diode, the anode end of the second switching diode is electrically connected to the controller local area network bus, and the data concentration processing unit is used to process data on the controller local area network bus.

[0014] According to some embodiments of the present application, a plurality of first resistors are further included, wherein the first resistors correspond one-to-one to the acquisition control unit, and the first receiving end of the acquisition control unit is electrically connected to the controller local area network bus through the corresponding first resistors.

[0015] According to some embodiments of the present application, a second resistor is further included, and the second receiving end of the data concentration processing unit is electrically connected to the controller area network bus through the second resistor.

[0016] According to some embodiments of the present application, the acquisition control unit is a motor acquisition control unit, the data concentration processing unit is a microprocessor, and one microprocessor corresponds to three motor acquisition control units.

[0017] According to some embodiments of the present application, the first resistor and the second resistor have the same resistance value.

[0018] According to some embodiments of the present application, the voltage pull-up unit includes a third resistor, one end of the third resistor is connected to the power supply voltage, and the other end is electrically connected to the controller area network bus.

[0019] According to the second aspect of the present application, a circuit board includes:

[0020] A controller area network communication circuit according to an embodiment of the first aspect of the present application.

[0021] A system according to a third aspect of the present application includes:

[0022] The circuit board of the second embodiment of the present application.

[0023] An electronic device according to a fourth aspect of the present application includes:

[0024] A system according to a third embodiment of the present application.

[0025] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0027] Figure 1 A schematic diagram of a controller area network communication circuit according to an embodiment of the present application;

[0028] Figure 2 A schematic diagram of a traditional controller area network communication circuit. DETAILED DESCRIPTION

[0029] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0030] In the description of the present application, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0031] In the description of this application, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, and "above", "below", "within", etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0032] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0033] Currently, refer to Figure 2 The controller area network communication circuit containing the transceiver chip can play a good role in the external circuit, but the internal communication does not require long-distance communication, and the internal communication environment does not have too many interference factors. Therefore, there is not much demand for the internal communication's anti-interference ability and long-distance transmission. Therefore, when the traditional controller area network communication circuit is used for internal communication, the circuit appears to be too complicated, and it causes a waste of resources and high cost.

[0034] Based on this, the present application proposes a controller area network communication circuit, which eliminates the use of transceiver chips, making the circuit more concise, while reducing production costs and improving resource utilization.

[0035] The following references Figure 1 The controller area network communication circuit of the embodiment of the present application is described.

[0036] It can be understood that: the controller local area network communication circuit of the embodiment of the present application includes: a controller local area network bus, multiple acquisition control units, a diode unit and a voltage pull-up unit, the acquisition control unit includes a first receiving end and a first sending end, the diode includes multiple first switching diodes, the multiple first switching diodes correspond one-to-one to the multiple acquisition control units, the first sending end of the acquisition control unit is electrically connected to the negative end of the corresponding first switching diode, the positive end of the first switching diode is electrically connected to the controller local area network bus, and the first switching diode is used to limit the interference of the external circuit to the acquisition control unit; the voltage pull-up unit is electrically connected to the controller local area network bus, and the voltage pull-up unit is used to output a high-level voltage to the controller local area network bus.

[0037] The beneficial effects of the controller area network communication circuit of the embodiment of the present application can be manifested as follows: by eliminating the use of transceiver chips, the circuit of the controller area network communication circuit is simplified and the production cost is reduced, which enables the controller area network communication circuit to be more suitable for internal communication. By arranging the first switching diode between the acquisition control unit and the controller area network bus, the interference of the external circuit to the acquisition control unit can be avoided, and the probability of risk is reduced. By setting a voltage pull-up unit, the voltage pull-up unit can be prompted to transmit a high-level voltage to the controller area network bus, thereby maintaining the controller area network bus in a high-level state when idle.

[0038] For example, in some embodiments, reference Figure 1In this embodiment, the CAN bus is a controller area network bus, D1, D3 and D4 are first switch diodes, the CAN_RX end of the acquisition control unit is the first receiving end, and the CAN_TX end of the acquisition control unit is the first transmitting end. The controller area network bus includes two communication lines, and the first transmitting end and the first receiving end of the acquisition control unit are electrically connected to the two communication lines respectively. The level state of the controller area network bus is reflected by the potential difference between the two communication lines. Therefore, the state of the controller area network bus is divided into dominant level and recessive level, which is equivalent to binary '0' and '1'. By setting a voltage pull-up unit, the controller area network bus can be kept in a recessive level state at idle time, which is equivalent to binary '1'. The setting of the diode unit can effectively avoid the interference of the external circuit on the acquisition control unit and prevent the current from flowing back from the first transmitting end to the controller area network bus. The controller area network bus is mounted with multiple acquisition control units, and each acquisition control unit is provided with a first switch diode, the positive terminal of the first switch diode is electrically connected to the controller area network bus, and the negative terminal is electrically connected to the first sending terminal of the acquisition control unit, so the current can only flow from the controller area network bus to the acquisition control unit. At the same time, compared with the traditional controller area network communication circuit, the present application eliminates the use of transceiver chips. Therefore, the circuit of the controller area network communication circuit of the present application is simpler, the installation and configuration are faster, and the labor cost and material cost are reduced. Because the applicable environment is internal communication, there is no need to consider the problem of long-distance transmission and excessive interference factors. Therefore, the effect that can be implemented by the controller area network communication circuit of the present application after deleting the transceiver chip is still almost the same as that of the traditional controller area network communication circuit, but the cost is greatly reduced.

[0039] Furthermore, each acquisition control unit has its corresponding binary identifier. The smaller the identifier, the higher the corresponding priority. Generally, the identifier has 11 bits. Before sending data to the controller LAN bus, the acquisition control unit needs to detect whether the controller LAN bus is in an idle state through the receiving end. The acquisition control unit will send the identifier only after determining that the controller LAN bus is in an idle state. Then the acquisition control unit sends its identifier from the high position in sequence. When the first sending end of the acquisition control unit is at a high level, it is regarded as the acquisition control unit sending a '1'. Due to the influence of the voltage pull-up unit, the state of the controller LAN bus is also at a high level when idle. At this time, the state of the controller LAN bus can be regarded as continuously maintaining '1', and the current usually flows from a high level to a low level. At this time, since the first sending end and the controller LAN bus are both at a high level, the current has no obvious flow trend, and the state of the first sending end and the controller LAN bus remains unchanged. Therefore, it can be seen that when the state of the acquisition control unit is '1', the controller LAN bus is not connected. There is no impact, so the state of the controller LAN bus remains unchanged and is still '1'. When the first sending end of the acquisition control unit is at a low level, it is regarded as the acquisition control unit sending '0'. Since the controller LAN bus is at a high level at this time, the current of the controller LAN bus will flow to the first sending end. At this time, the state of the controller LAN bus will be converted from a recessive level (high level) to a dominant level (low level), that is, binary '0', and finally the state data of the controller LAN bus ('0' or '1') will be transmitted to the first receiving end and compared with the identifier of the acquisition control unit. When the identifier and the data fed back by the controller LAN bus are completely correct, the acquisition control unit obtains the right to use the controller LAN bus, but when the sending of the identifier is inconsistent with the data fed back by the controller LAN bus, the acquisition control unit will report an error and immediately stop sending subsequent identifiers.

[0040] Furthermore, when multiple acquisition control units send data to the controller area network bus at the same time, the acquisition control unit with a high priority can have priority in mastering the right to use the controller area network. For example, when two acquisition control units send data to the controller area network bus at the same time, the two acquisition control units send their identifiers in turn from the high position. At a certain moment, the acquisition control unit with a high priority sends '0' and the acquisition control unit with a low priority sends '1'. At this time, the current of the controller area network bus flows to the first sending end of the acquisition control unit with a high priority, so the level state of the controller area network bus changes from '1' to '0'. If the first receiving end of the acquisition control unit with a low priority receives the feedback data of the controller area network bus and compares it with the identifier sent by the acquisition control unit and finds that it is inconsistent, it stops sending subsequent identifiers, and the acquisition control unit with a high priority continues to send identifiers until it is confirmed that all identifiers are completely consistent with the feedback data of the controller area network bus. Then, the acquisition control unit with a high priority obtains the right to use the controller area network bus. In this way, the orderly operation of multiple acquisition control units can be achieved.

[0041] It should be noted that the acquisition control unit can be a common acquisition control unit such as a motor acquisition control unit, a rearview mirror acquisition control unit, a lighting acquisition control unit and an instrument acquisition control unit; the model of the first switching diode can be a common diode model such as ESD15B330TR and ESD24R030TR.

[0042] It can be understood that: the controller area network communication circuit of the embodiment of the present application also includes a data concentration processing unit, the diode unit also includes a second switching diode, the data concentration processing unit includes a second receiving end and a second transmitting end, the second receiving end of the data concentration processing unit is electrically connected to the controller area network bus, the second transmitting end of the data concentration processing unit is electrically connected to the cathode end of the second switching diode, the anode end of the second switching diode is electrically connected to the controller area network bus, and the data concentration processing unit is used to process data of the controller area network bus.

[0043] For example, in some embodiments, reference Figure 1 In addition to the acquisition control unit, there is also a data concentration processing unit, and the data concentration processing unit is provided with a second switch diode, the cathode end of the second switch diode is electrically connected to the data concentration processing unit, and the anode end is electrically connected to the controller area network bus. In this embodiment, D2 is the second switch diode, the CAN_RX end of the data concentration processing unit is the second receiving end, and the CAN_TX end of the data concentration processing unit is the second receiving end. The data concentration processing unit also has an identifier, and the process of the data concentration processing unit obtaining the right to use the controller area network bus is the same as that of the acquisition control unit, so it will not be described in detail here.

[0044] It should be noted that: the data concentration processing unit may be a microprocessor and a memory, etc.; the model of the second switch diode may be a common diode model such as ESD15B330TR and ESD24R030TR.

[0045] It can be understood that: the controller area network communication circuit of the embodiment of the present application also includes multiple first resistors, the first resistors correspond to the acquisition control units one by one, and the first receiving end of the acquisition control unit is electrically connected to the controller area network bus through the corresponding first resistors.

[0046] For example, in some embodiments, reference Figure 1 A first resistor is provided between the first receiving end of the acquisition control unit and the controller area network bus, and the first resistor is electrically connected to the first receiving end and the controller area network bus respectively. In this embodiment, R7, R10 and R11 are the first resistors. The first resistor is actually used as a matching resistor. By setting the first resistor, the integrity of the data signal transmission of the acquisition control unit is ensured, and it is ensured that the CAN_RX end of the acquisition control unit detects the level data of the bus in real time, rather than the level data of its own CAN_TX end, and this setting also reduces the reflection and loss of the data signal.

[0047] It can be understood that: the controller area network communication circuit of the embodiment of the present application further includes a second resistor, and the second receiving end of the data concentration processing unit is electrically connected to the controller area network bus through the second resistor.

[0048] For example, in some embodiments, reference Figure 1 A second resistor is provided between the second receiving end of the controller and the controller LAN bus, and the second resistor is electrically connected to the second receiving end and the controller LAN bus respectively. In this embodiment, R9 is the second resistor, and the second resistor is actually also used as a matching resistor. By setting the second resistor, the integrity of the data signal transmission of the data concentration processing unit is ensured, and the reflection and loss of the data signal are reduced.

[0049] It can be understood that: the acquisition control unit is a motor acquisition control unit, the data concentration processing unit is a microprocessor, and one microprocessor corresponds to three motor acquisition control units.

[0050] Exemplarily, in some embodiments, the acquisition control unit is set as a motor control unit, and the data concentration processing unit is set as a microprocessor (not shown in the drawings). One microprocessor can process the data of three motor acquisition control units at the same time, which can maximize the performance of the microprocessor and avoid waste of resources.

[0051] It can be understood that the resistance values ​​of the first resistor and the second resistor are the same.

[0052] For example, in some embodiments, reference Figure 1 The resistance values ​​of the second resistor (R9) and the first resistors (R7, R10 and R11) are all 120 ohms. The same matching resistance makes the circuit more stable while reducing the reflection and loss of the data signal of the data concentration processing unit, thereby improving the quality and efficiency of data processing.

[0053] It can be understood that: the voltage pull-up unit includes a third resistor, one end of the third resistor is connected to the power supply voltage, and the other end of the third resistor is electrically connected to the controller area network bus.

[0054] For example, in some embodiments, reference Figure 1 One end of the third resistor is connected to the 3.3 volt power supply voltage, and the other end is electrically connected to the controller area network bus. In this embodiment, R8 is the third resistor. The third resistor, as a voltage pull-up unit, can better pull up the voltage of the controller area network bus, and the cost of the resistor is low. Therefore, using the resistor as a voltage pull-up unit can more effectively save manufacturing costs.

[0055] The circuit board according to the second aspect embodiment of the application includes the controller area network communication circuit of the first aspect embodiment of the application.

[0056] According to the controller area network communication circuit of the embodiment of the present application, by eliminating the use of transceiver chips, the circuit of the controller area network communication circuit is simplified and the production cost is reduced, so that the controller area network communication circuit can be more suitable for internal communication. By arranging the first switch diode between the acquisition control unit and the controller area network bus, the interference of the external circuit to the acquisition control unit can be avoided, and the probability of risk is reduced. By setting the voltage pull-up unit, the voltage pull-up unit can be caused to transmit a high-level voltage to the controller area network bus, thereby maintaining the controller area network bus in a high-level state when idle. By using the controller area network communication circuit of the present application, the circuit of the circuit board can be simplified and the labor and product costs can be reduced.

[0057] The system according to the third aspect embodiment of the application includes the circuit board of the second aspect embodiment of the application.

[0058] According to the circuit board of the embodiment of the present application, by using the controller area network communication circuit of the present application, the system response is faster, thereby improving the working efficiency of the system.

[0059] An electronic device according to an embodiment of the fourth aspect of the present application includes the system of the embodiment of the third aspect of the present application.

[0060] According to the system of the embodiment of the present application, by using the circuit board of the present application, the overall appearance of the electronic device is made more compact and the circuit is more convenient.

[0061] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present application.

Claims

1. A controller area network communication circuit, comprising a controller area network bus and a plurality of acquisition control units, wherein the acquisition control unit comprises a first receiving end and a first transmitting end; characterized in that: The controller area network communication circuit also includes: A diode unit, wherein the diode unit comprises a plurality of first switch diodes, wherein the plurality of first switch diodes correspond one-to-one to the plurality of acquisition control units, wherein the first transmitting end of the acquisition control unit is electrically connected to the cathode end of the corresponding first switch diode, and the anode end of the first switch diode is electrically connected to the controller area network bus, and the first switch diode is used to limit interference of an external circuit on the acquisition control unit; A voltage pull-up unit is electrically connected to the controller area network bus and is used to output a high level voltage to the controller area network bus.

2. The controller area network communication circuit according to claim 1, characterized in that: It also includes a data concentration processing unit, the diode unit also includes a second switch diode, the data concentration processing unit includes a second receiving end and a second transmitting end, the second receiving end of the data concentration processing unit is electrically connected to the controller local area network bus, the second transmitting end of the data concentration processing unit is electrically connected to the cathode end of the second switch diode, the anode end of the second switch diode is electrically connected to the controller local area network bus, and the data concentration processing unit is used to process data on the controller local area network bus.

3. The controller area network communication circuit according to claim 2, characterized in that: It also includes a plurality of first resistors, wherein the first resistors correspond to the acquisition control units one by one, and the first receiving end of the acquisition control unit is electrically connected to the controller area network bus through the corresponding first resistors.

4. The controller area network communication circuit according to claim 3, characterized in that: It also includes a second resistor, and the second receiving end of the data concentration processing unit is electrically connected to the controller area network bus through the second resistor.

5. The controller area network communication circuit according to claim 4, characterized in that: The acquisition control unit is a motor acquisition control unit, the data concentration processing unit is a microprocessor, and one microprocessor corresponds to three motor acquisition control units.

6. The controller area network communication circuit according to claim 4, characterized in that: The first resistor and the second resistor have the same resistance value.

7. The controller area network communication circuit according to claim 1, characterized in that: The voltage pull-up unit comprises a third resistor, one end of which is connected to the power supply voltage, and the other end of which is electrically connected to the controller area network bus.

8. A circuit board, characterized in that: include: A controller area network communication circuit as claimed in any one of claims 1 to 7.

9. A system, characterized in that: include: The circuit board as claimed in claim 8.

10. An electronic device, characterized in that: include: The system as claimed in claim 9.

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