CAN communication circuit compatible with optical fiber and wiring mode

Abstract

A CAN communication circuit compatible with an optical fiber and a wiring mode belongs to the technical field of communication, and comprises a CAN communication circuit of a first CPU channel, a CAN communication circuit of a second CPU channel, an isolation power supply, an optical fiber CAN communication circuit and a bus matching circuit, the CAN communication circuit of the first CPU channel and the CAN communication circuit of the second CPU channel are connected with the isolation power supply, and the optical fiber CAN communication circuit is connected with the bus matching circuit. The CAN communication circuit of the first CPU channel and the CAN communication circuit of the second CPU channel are connected with the bus matching circuit, and the optical fiber CAN communication circuit is connected with the bus matching circuit. The CAN bus communication circuit is compatible with a communication circuit in a traditional wiring mode, is suitable for being applied to occasions with common short distance and relatively low electromagnetic interference, is compatible with occasions with long distance and high electromagnetic interference, and can coexist on the CAN communication bus at the same time, and a proper communication mode can be selected according to the application occasions when the CAN bus communication circuit is used.

Description

Technical Field

[0001] This utility model belongs to the field of communication technology, specifically relating to a CAN communication circuit compatible with both optical fiber and wiring methods. Background Technology

[0002] As a fieldbus with increasingly widespread applications, the CAN bus has always used metal twisted-pair shielded wire as the networking transmission medium. Although the CAN bus using differential transmission usually has good anti-interference capabilities, it is not suitable for some special applications, such as those with harsh electromagnetic environments, high voltage, and strong magnetic fields.

[0003] Traditional industrial CAN communication typically uses differential transmission with twisted-pair shielded cables. However, with technological advancements and evolving industry standards, new functions such as data monitoring and fault diagnosis have emerged, necessitating expansion beyond the original communication infrastructure. The harsh communication environment, the addition of CAN communication nodes, and the connection of communication cables can introduce new problems such as interference, affecting the original critical communication data and consequently impacting the normal operation of the equipment.

[0004] With the rapid development of optical fiber communication technology, optical fiber, as an emerging information transmission medium, possesses unique characteristics such as immunity to electromagnetic interference and excellent qualities like resistance to harsh environments, non-radiation of electromagnetic waves, and non-conductivity. Therefore, based on the analysis of the characteristics of the twisted-pair CAN bus, this paper proposes a CAN communication circuit interface and network configuration compatible with both optical fiber and wiring methods to address the shortcomings of traditional CAN communication wiring methods, thereby promoting the development and application of optical fiber CAN bus terminals. Utility Model Content

[0005] To address the shortcomings of existing traditional CAN communication wiring methods, a CAN communication circuit interface and network configuration compatible with both fiber optic and wired connections is proposed. This not only meets the needs of traditional CAN communication in short-distance applications with relatively low electromagnetic interference, but also supports long-distance applications with strong electromagnetic interference. Both circuits coexist on the CAN communication bus, allowing users to select the appropriate communication method based on the application scenario.

[0006] To achieve the above objectives, the technical solution of this utility model is as follows:

[0007] A CAN communication circuit compatible with fiber optics and wiring methods includes: a CAN communication circuit for a first CPU path, a CAN communication circuit for a second CPU path, an isolation power supply, a fiber optic CAN communication circuit, and a bus matching circuit. The CAN communication circuit for the first CPU path, the CAN communication circuit for the second CPU path, and the fiber optic CAN communication circuit are connected to the isolation power supply. The CAN communication circuit for the first CPU path and the CAN communication circuit for the second CPU path are connected to the bus matching circuit. The fiber optic CAN communication circuit is also connected to the bus matching circuit.

[0008] The CAN communication circuit of the first CPU path includes a first CPU, a first isolation driver chip, and a first CAN communication chip. The first CPU, the first isolation driver chip, and the first CAN communication chip are connected in sequence. The first CAN communication chip is connected to the bus matching circuit through an interference suppression circuit.

[0009] Furthermore, the CAN communication circuit of the second CPU path includes a second CPU, a second isolation driver chip, and a second CAN communication chip. The second CPU, the second isolation driver chip, and the second CAN communication chip are connected in sequence. The second CAN communication chip is connected to the bus matching circuit through an interference suppression circuit.

[0010] Furthermore, the fiber optic CAN communication circuit includes a fiber optic transceiver, a fiber optic driver circuit, and a third CAN communication chip, which are connected in sequence. The third CAN communication chip is connected to a bus matching circuit.

[0011] In the circuit described above, the first CPU processes the CAN communication data reception and transmission signals. After processing, the data is transmitted via the TX signal line and connected to the first isolation driver chip. Simultaneously, it receives the signal returned by the first isolation driver chip via the RX signal line. The first isolation driver chip is connected to the first CAN communication chip. The first CAN communication chip is connected to the interference suppression circuit.

[0012] In the circuit described above, the second CPU processes the CAN communication data reception and transmission signals. After processing, the data is transmitted via the TX signal line and connected to the second isolation driver chip. Simultaneously, it receives the signal returned by the second isolation driver chip via the RX signal line. The second isolation driver chip is connected to the second CAN communication chip. The second CAN communication chip is connected to the interference suppression circuit. The interference suppression circuit is connected to the CAN bus matching circuit and to the wiring interface.

[0013] The CAN bus matching circuit is also connected to the third CAN communication chip of the TJA1051T. The TJA1051T CAN communication chip is connected to the fiber optic driver circuit, which in turn is connected to the fiber optic transceiver. The isolation power supply is connected to the first and second isolation driver chips, the first and second CAN communication chips, and the interference suppression circuit. It is also connected to the TJA1051T CAN communication chip, the fiber optic driver circuit, and the fiber optic transceiver for power supply.

[0014] The first isolation driver chip is connected to the first CPU and the first CAN communication chip to isolate the CAN communication received and transmitted signals. The second isolation driver chip is connected to the second CPU and the second CAN communication chip to isolate the CAN communication received and transmitted signals.

[0015] The first CAN communication chip is connected to the first isolation driver chip and to the interference suppression circuit. The second CAN communication chip is connected to the second isolation driver chip and to the interference suppression circuit. The CAN communication chips perform CAN protocol conversion and priority transmission arbitration.

[0016] The interference suppression circuit is connected to the first CAN communication chip and the second CAN communication chip, to the wiring interface, and to the bus matching circuit, thereby playing an interference suppression role.

[0017] The bus matching circuit is connected to the interference suppression circuit, the third CAN communication chip of TJA1051T, and the wiring interface.

[0018] The third CAN communication chip of the TJA1051T is connected to the fiber optic driver circuit and the CAN bus matching circuit.

[0019] The fiber optic drive circuit is connected to the third CAN communication chip of TJA1051T and also to the fiber optic transceiver.

[0020] The fiber optic transceiver is connected to the fiber optic drive circuit.

[0021] The beneficial effects of this utility model are:

[0022] The main function of a CAN communication circuit that is compatible with both fiber optic and wired communication methods is to be compatible with traditional wired communication circuits, making it suitable for general short-distance applications with relatively low electromagnetic interference, while also being compatible with long-distance applications with strong electromagnetic interference. Both types of circuits coexist on the CAN communication bus, and the appropriate communication method can be selected according to the application.

[0023] Advantages of CAN communication optical transceiver technology:

[0024] 1. Long-distance communication: The CAN optical transceiver transmits signals through optical fiber, effectively solving the problem of electromagnetic interference and supporting communication distances of tens of kilometers.

[0025] 2. High-speed data transmission: The high bandwidth of fiber optic communication enables CAN optical transceivers to achieve high-speed data transmission, meeting the real-time requirements of industrial automation.

[0026] 3. Enhanced reliability: The low loss and high stability of optical fiber improve the reliability of CAN bus communication.

[0027] 4. Data security: The immunity of fiber optic communication makes CAN optical transceivers more secure during data transmission.

[0028] 5. Easy to expand: CAN optical transceivers support multiplexing technology, which facilitates system expansion and upgrades. Attached Figure Description

[0029] Figure 1 This is a block diagram of the CAN communication principle of this utility model, which is compatible with both optical fiber and wiring methods.

[0030] Figure 2 This is the principle of the CAN communication part of this utility model. Figure 1 ;

[0031] Figure 3 This is the principle of the CAN communication part of this utility model. Figure 2 .

[0032] The attached figures are labeled as follows:

[0033] 1. First CPU, 2. First isolation driver chip, 3. First CAN communication chip, 4. Interference suppression circuit, 5. Bus matching circuit, 6. Wiring interface, 7. Second CPU, 8. Second isolation driver chip, 9. Second CAN communication chip, 10. Isolation power supply, 11. Fiber optic transceiver, 12. Fiber optic driver circuit, 13. Third CAN communication chip. Detailed Implementation

[0034] Example 1

[0035] With the rapid development of optical fiber communication technology, optical fiber, as an emerging information transmission medium, possesses unique characteristics of being free from electromagnetic interference and exhibiting excellent qualities such as resistance to harsh environments, non-radiation of electromagnetic waves, and non-conductivity. Therefore, based on the analysis of the characteristics of the twisted-pair CAN bus, this paper proposes a CAN communication circuit interface and network configuration compatible with both optical fiber and wiring methods to address the shortcomings of traditional CAN communication wiring methods, thereby promoting the development and application of optical fiber CAN bus terminals.

[0036] A CAN communication circuit compatible with both fiber optic and wired connections, such as Figures 1-3 As shown, it includes a CAN communication circuit for a first CPU path, a CAN communication circuit for a second CPU path, an isolation power supply 10, a fiber optic CAN communication circuit, and a bus matching circuit 5. The CAN communication circuits for the first CPU path, the second CPU path, and the fiber optic CAN communication circuit are connected to the isolation power supply 10. The CAN communication circuits for the first CPU path and the second CPU path are connected to the bus matching circuit 5. The fiber optic CAN communication circuit is also connected to the bus matching circuit 5.

[0037] The CAN communication circuit of the first CPU path includes a first CPU1, a first isolation driver chip2 and a first CAN communication chip3. The first CPU1, the first isolation driver chip2 and the first CAN communication chip3 are connected in sequence. The first CAN communication chip3 is connected to the bus matching circuit5 through the interference suppression circuit4.

[0038] The CAN communication circuit of the second CPU path includes a second CPU 7, a second isolation driver chip 8, and a second CAN communication chip 9. The second CPU 7, the second isolation driver chip 8, and the second CAN communication chip 9 are connected in sequence. The second CAN communication chip 9 is connected to the bus matching circuit 5 through the interference suppression circuit 4.

[0039] The fiber optic CAN communication circuit includes a fiber optic transceiver 11, a fiber optic driver circuit 12, and a third CAN communication chip 13. The fiber optic transceiver 11, the fiber optic driver circuit 12, and the third CAN communication chip 13 are connected in sequence, and the third CAN communication chip 13 is connected to the bus matching circuit 5.

[0040] The isolation power supply 10 is connected to the first isolation driver chip 2, the second isolation driver chip 8, the first CAN communication chip 3, the second CAN communication chip 9, and the interference suppression circuit 4. At the same time, the isolation power supply 10 is connected to the third CAN communication chip 13, the fiber optic driver circuit 12, and the fiber optic transceiver 11 to provide power.

[0041] The bus matching circuit 5 is connected to external devices via the wiring interface 6.

[0042] Among them, the first CAN communication chip 3, the second CAN communication chip 9, and the third CAN communication chip 13 adopt the TJA1051T chip.

[0043] Both the first isolation driver chip and the second isolation driver chip use the IL721-3 chip; the fiber optic driver circuit uses the EL7202 chip.

[0044] Example 2

[0045] like Figure 1 As shown, a CAN communication circuit compatible with both fiber optic and wired connections mainly consists of a CAN communication circuit with a first CPU path, a CAN communication circuit with a second CPU path, an isolation power supply, a fiber optic CAN communication circuit, and a bus matching circuit.

[0046] In the circuit described above, the first CPU 1 processes the CAN communication data receiving and transmitting signals. After processing, it connects to the first isolation driver chip 2 via the transmit TX signal line and simultaneously receives the signal returned by the first isolation driver chip 2 to the RX signal line. The first isolation driver chip 2 is connected to the first CAN communication chip 3. The first CAN communication chip 3 is connected to the interference suppression circuit 4. In the circuit described above, the second CPU 7 processes the CAN communication data receiving and transmitting signals. After processing, it connects to the second isolation driver chip 8 via the transmit TX signal line and simultaneously receives the signal returned by the second isolation driver chip 8 to the RX signal line. The second isolation driver chip 8 is connected to the second CAN communication chip 9. The second CAN communication chip 9 is connected to the interference suppression circuit 4. The interference suppression circuit 4 is connected to the CAN bus matching circuit 5 and the wiring interface 6. The CAN bus matching circuit 5 is also connected to the third CAN communication chip 13 of the TJA1051T. The third CAN communication chip 13 of the TJA1051T is connected to the fiber optic driver circuit 12, and the fiber optic driver circuit 12 is connected to the fiber optic transceiver 11. The isolation power supply 10 is connected to the first isolation driver chip 2 and the second isolation driver chip 8, the first CAN communication chip 3 and the second CAN communication chip 9, and the interference suppression circuit 4. It is also connected to the third CAN communication chip 13 of TJA1051T, the fiber optic driver circuit 12 and the fiber optic transceiver 11 for power supply.

[0047] The first isolation driver chip 2 is connected to the first CPU 1 and the first CAN communication chip 3 to isolate the CAN communication received and transmitted signals. The second isolation driver chip 8 is connected to the second CPU 7 and the second CAN communication chip 9 to isolate the CAN communication received and transmitted signals.

[0048] The first CAN communication chip 3 is connected to the first isolation driver chip 2 and to the interference suppression circuit 4. The second CAN communication chip 9 is connected to the second isolation driver chip 8 and to the interference suppression circuit 4. The CAN communication chips perform CAN protocol conversion and priority transmission arbitration.

[0049] The interference suppression circuit 4 is connected to the first CAN communication chip 3 and the second CAN communication chip 9, connected to the wiring interface 6, and connected to the bus matching circuit 5, thereby playing an interference suppression role.

[0050] The bus matching circuit 5 is connected to the interference suppression circuit 4, the third CAN communication chip 13 of the TJA1051T, and the wiring interface 6.

[0051] The third CAN communication chip 13 of the TJA1051T is connected to the fiber optic driver circuit 12 and the CAN bus matching circuit 5.

[0052] The fiber optic drive circuit 12 is connected to the third CAN communication chip 13 of the TJA1051T, and is also connected to the fiber optic transceiver 11.

[0053] The fiber optic transceiver 11 is connected to the fiber optic drive circuit 12.

[0054] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A CAN communication circuit compatible with both fiber optic and wired connections, characterized in that, It includes a CAN communication circuit for the first CPU path, a CAN communication circuit for the second CPU path, an isolation power supply (10), an optical fiber CAN communication circuit, and a bus matching circuit (5). The CAN communication circuit for the first CPU path, the CAN communication circuit for the second CPU path, and the optical fiber CAN communication circuit are connected to the isolation power supply (10). The CAN communication circuit for the first CPU path and the CAN communication circuit for the second CPU path are connected to the bus matching circuit (5). The optical fiber CAN communication circuit is connected to the bus matching circuit (5).

2. The CAN communication circuit compatible with both optical fiber and wiring methods according to claim 1, characterized in that, The CAN communication circuit of the first CPU path includes a first CPU (1), a first isolation driver chip (2) and a first CAN communication chip (3). The first CPU (1), the first isolation driver chip (2) and the first CAN communication chip (3) are connected in sequence. The first CAN communication chip (3) is connected to the bus matching circuit (5) through the interference suppression circuit (4).

3. The CAN communication circuit compatible with both optical fiber and wiring methods according to claim 2, characterized in that, The CAN communication circuit of the second CPU path includes a second CPU (7), a second isolation driver chip (8), and a second CAN communication chip (9). The second CPU (7), the second isolation driver chip (8), and the second CAN communication chip (9) are connected in sequence. The second CAN communication chip (9) is connected to the bus matching circuit (5) through the interference suppression circuit (4).

4. The CAN communication circuit compatible with both optical fiber and wiring methods according to claim 3, characterized in that, The fiber optic CAN communication circuit includes a fiber optic transceiver (11), a fiber optic driver circuit (12), and a third CAN communication chip (13). The fiber optic transceiver (11), the fiber optic driver circuit (12), and the third CAN communication chip (13) are connected in sequence. The third CAN communication chip (13) is connected to the bus matching circuit (5).

5. The CAN communication circuit compatible with both optical fiber and wiring methods according to claim 4, characterized in that, The isolation power supply (10) is connected to the first isolation driver chip (2), the second isolation driver chip (8), the first CAN communication chip (3), the second CAN communication chip (9), and the interference suppression circuit (4). At the same time, the isolation power supply (10) is connected to the third CAN communication chip (13), the fiber optic driver circuit (12), and the fiber optic transceiver (11) for power supply.

6. The CAN communication circuit compatible with both optical fiber and wiring methods according to claim 5, characterized in that, The bus matching circuit (5) is connected to external devices through the wiring interface (6).

7. The CAN communication circuit compatible with both optical fiber and wiring methods according to claim 6, characterized in that, The first CAN communication chip (3), the second CAN communication chip (9), and the third CAN communication chip (13) all use TJA1051T chips.

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