Data transmission circuit, transmission system and transmission equipment
By introducing a transformer isolation module into the RS-485 communication system to electrically isolate the communication chip, the problems of system susceptibility to interference and noise are solved, and the data transmission quality and system stability are improved.
Patent Information
- Application Number
- CN202520016852.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-03
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2035-01-03
AI Technical Summary
RS-485 communication systems are susceptible to electrical interference and noise in industrial environments, which can lead to a decrease in data integrity and accuracy, and make the communication chips vulnerable to damage.
A transformer isolation module is used to electrically isolate the communication chip from external devices, thus protecting the communication chip from electrical noise, surge voltage, and other factors.
An electromagnetic isolation module for the communication chip was implemented. Through this isolation module, electromagnetic isolation of the communication chip was achieved, thereby protecting the communication chip and improving data transmission quality and system stability.
Smart Images
Figure CN223650996U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of communication technology, and in particular to a data transmission circuit, transmission system and transmission equipment. Background Technology
[0002] RS-485 communication, as a widely used serial communication method, plays an indispensable role in many fields. It connects to external devices through specially designed RS-485 communication chips (such as MAX485 and SN65HVD230), enabling long-distance, multi-point communication and efficient data transmission. The RS-485 standard not only supports long transmission distances but also allows up to 32 nodes to be connected on the same bus (which can be further expanded using repeaters), making it particularly suitable for distributed control systems and networked applications.
[0003] In industrial environments, RS-485 communication systems often face complex electrical conditions and harsh operating environments. Especially in certain applications, one end of the RS-485 communication may be directly connected to high-voltage equipment, such as frequency converters, power switchgear, or large motor controllers. If these devices lack proper electrical isolation, high-voltage electricity may be transmitted through the RS-485 line to the downstream circuitry, potentially causing serious damage to other connected low-voltage equipment, or even posing a risk of electric shock and threatening the lives of operators.
[0004] Furthermore, industrial environments are filled with various potential sources of interference, posing a significant challenge to the stability and data integrity of RS-485 communication systems.
[0005] Electromagnetic interference (EMI):
[0006] Inside a factory workshop, numerous electric motors, transformers, and other high-power electrical equipment generate strong electromagnetic fields. These magnetic fields can couple onto RS-485 communication lines, causing signal distortion or complete loss. For example, when a large motor starts, the transient current it generates can induce significant noise voltages in nearby communication cables, affecting the quality of data transmission.
[0007] Electrostatic Discharge (ESD):
[0008] Electrostatic discharge (ESD) is another common problem, especially in dry environments or when handling insulating materials such as plastics and rubber. Static electricity buildup can cause sudden high-voltage pulses that can easily damage sensitive electronic components and are difficult to predict and control.
[0009] Surge voltage:
[0010] Transient overvoltage events caused by lightning, switching operations, or other reasons are also risk factors that cannot be ignored. These surge voltages can not only damage the RS-485 communication chip itself, but may also propagate along the communication line, endangering all connected devices throughout the network. Utility Model Content
[0011] In view of this, the present application provides a data transmission circuit, transmission system and transmission device, which can effectively solve the problems in the prior art where external devices are easily interfered with in RS-485 communication, thereby compromising the integrity and accuracy of data, and may also cause physical damage to the 485 communication chip itself, resulting in unpredictable impacts.
[0012] In a first aspect, embodiments of this application provide a data transmission circuit, including: a communication chip and a transformer isolation module, one end of the communication chip being used to connect to a main controller, the other end of the communication chip being electrically connected to one end of the transformer isolation module, and the other end of the transformer isolation module being used to connect to an external device;
[0013] The main controller is used to transmit data with the external device using the communication chip;
[0014] The transformer isolation module is used to electrically isolate the communication chip from the external device in order to protect the communication chip.
[0015] In some embodiments, the communication chip includes a first port, a second port, and a third port, wherein the first port and the second port are electrically connected to the transformer isolation module, and the third port is electrically connected to the main controller.
[0016] In some embodiments, the transformer isolation module includes a first isolation transformer, the primary winding of which is electrically connected to the first port and the second port, and the secondary winding of which is used to connect to the external device.
[0017] In some embodiments, if the number of communication chips is N, where N is a positive integer greater than 1, each of the communication chips is electrically connected to each external device of the external device group through the transformer isolation module;
[0018] The transformer isolation module is used to isolate each of the communication chips from each of the external devices in the external device group, thereby protecting each of the communication chips.
[0019] In some embodiments, the transformer isolation module includes N isolation transformers, and each of the communication chips is electrically connected to each of the external devices in the external device group through the respective isolation transformers.
[0020] In some embodiments, the communication chip is a 485 communication chip.
[0021] In some embodiments, the first port is the positive differential signal port, and the second port is the negative differential signal port.
[0022] In some embodiments, the turns ratio of the isolation transformer in the transformer isolation module is 1:1.
[0023] Secondly, embodiments of this application provide a data transmission system, the data transmission system including the main controller and at least one data transmission circuit as described in the first aspect above.
[0024] Thirdly, embodiments of this application provide a data transmission device, wherein the data transmission device is provided with at least one data transmission system as described in the second aspect above.
[0025] The embodiments of this application have the following beneficial effects:
[0026] The data transmission circuit of this application includes a communication chip and a transformer isolation module. One end of the communication chip is used to connect to the main controller, and the other end of the communication chip is electrically connected to one end of the transformer isolation module. The other end of the transformer isolation module is used to connect to external devices. The main controller is used to transmit data with external devices using the communication chip. The data transmission circuit of this application uses the transformer isolation module to electrically isolate the communication chip from external devices, which improves the data transmission quality and protects the communication chip from damage caused by electrical noise and surge voltage, greatly improving the stability of the system. Attached Figure Description
[0027] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0028] Figure 1 A first structural schematic diagram of the data transmission circuit according to an embodiment of this application is shown;
[0029] Figure 2 A second structural schematic diagram of the data transmission circuit according to an embodiment of this application is shown;
[0030] Figure 3 A third structural schematic diagram of the data transmission circuit according to an embodiment of this application is shown;
[0031] Figure 4 A circuit diagram of the data transmission circuit according to an embodiment of this application is shown.
[0032] Explanation of key component symbols:
[0033] 10: Communication chip; 11: External device group; 20: Transformer isolation module; 30: Main controller; 40: External device; 201: First isolation transformer. Detailed Implementation
[0034] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.
[0035] The components of the embodiments of this application described and illustrated in the accompanying drawings can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0036] In the following text, the terms "comprising," "having," and their cognates, which may be used in various embodiments of this application, are intended only to indicate a particular feature, number, step, operation, element, component, or combination thereof, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, or adding the possibility of one or more combinations thereof. Furthermore, the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.
[0037] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of this application pertain. Terms (such as those defined in commonly used dictionaries) shall be interpreted as having the same meaning as in their contextual meaning in the relevant technical field and shall not be construed as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of this application.
[0038] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0039] Considering that existing RS-485 communication solutions are susceptible to interference from external devices, which can compromise data integrity and accuracy and potentially cause physical damage to the RS-485 communication chip itself, leading to unpredictable consequences, this application provides a data transmission circuit, transmission system, and transmission device. The data transmission circuit of this application utilizes a transformer isolation module to electrically isolate the communication chip from external devices, improving data transmission quality while also protecting the communication chip from damage caused by electrical noise and surge voltage, thus significantly enhancing system stability.
[0040] The data transmission circuit will be described below with reference to some specific embodiments.
[0041] Figure 1 A schematic diagram of a data transmission circuit according to an embodiment of this application is shown. Exemplarily, the data transmission circuit includes: a communication chip 10 and a transformer isolation module 20. One end of the communication chip 10 is connected to the main controller 30, and the other end of the communication chip 10 is electrically connected to an external device 40 through the transformer isolation module 20. Specifically, the communication chip 10 can be any type of communication chip; it can be a RS-232 communication chip or a RS-485 communication chip. Exemplarily, the communication chip 10 is a RS-485 communication chip. The RS-485 communication chip can convert the logic level signal generated by the main controller 30 into a differential signal suitable for long-distance transmission and transmit the differential signal to the external device 40 using a transmission line. The RS-485 communication chip can also convert the differential signal generated by the external device 40 into a logic level signal and transmit it to the main controller 30, thereby realizing data transmission.
[0042] Understandably, the main controller 30 is the system's control module and can be any type of controller. The main controller 30 can be an MCU, a DSP, an FPGA, etc. The external device 40 can be, but is not limited to, various sensors, or other devices. For example, the external device 40 can be an actuator, a data acquisition unit, a smart meter, a communication gateway, a security device, or a monitoring device, etc.
[0043] The transformer isolation module 20 is used to electrically isolate the communication chip 10 from the external device 40, thereby protecting the communication chip 10. Specifically, Figure 2The diagram shows another structural schematic of the data transmission circuit according to an embodiment of this application. The communication chip 10 includes a first port, a second port, and a third port. The first port is electrically connected to the transformer isolation module 20, the second port is electrically connected to the transformer isolation module 20, and the third port is electrically connected to the main controller 30. Specifically, the first port is the positive differential signal port of the 485 communication chip, connected to pin A of the 485 communication chip, and is called port A. The second port is the negative differential signal port of the 485 communication chip, connected to pin B of the 485 communication chip, and is called port B. Port A is the positive signal port of the 485 communication chip, and port B is the negative signal port, with their potentials opposite to those of port A, forming a differential pair.
[0044] The transformer isolation module 20 includes a first isolation transformer 201. The primary winding of the first isolation transformer 201 is electrically connected to the first port and the second port. The secondary winding of the first isolation transformer 201 is used to connect to the external device 40. The turns ratio of the first isolation transformer 201 can be set according to the actual application. For example, the turns ratio of the isolation transformer in the transformer isolation module 20 is 1:1.
[0045] The first isolation transformer 201 can electrically isolate the input signal and the output signal, prevent interference from DC and abnormal AC power between power systems, and support the transmission of signals and electrical energy, improve the safety and stability of the power system, and reduce the impact of electromagnetic interference and noise on communication quality.
[0046] Specifically, utilizing the electromagnetic induction principle of a transformer, when the 485 communication chip sends a signal to the primary winding of the first isolation transformer 201, the first isolation transformer 201 generates an induced electromotive force in the secondary coil, which is output through the secondary winding, thereby transmitting the signal to the external device 40. Since the first isolation transformer 201 is equipped with an insulating layer, the insulating layer can disconnect the electrical connection between the input and output terminals, thus ensuring that the signal can be transmitted while achieving electrical isolation.
[0047] The first isolation transformer 201 can also provide lightning protection. If the 485 communication chip is working in harsh environments such as industrial environments, the first isolation transformer 201 can protect the 485 communication chip from damage caused by natural phenomena such as lightning, further improving the stability of the system.
[0048] Furthermore, the first isolation transformer 201, through its unique winding structure and electromagnetic coupling principle, can enhance signal transmission capability. Specifically, the first isolation transformer 201 utilizes differentially coupled coil coupling filtering to enhance the differential signal output by the 485 communication chip, enabling the signal to better resist attenuation during transmission and thus extending the signal transmission distance. The first isolation transformer 201 can be configured to meet both signal transmission and isolation requirements by adjusting its turns ratio and parameters.
[0049] As another implementation, an isolation power supply can be used to electrically isolate the communication chip 10 from the external device 40 to protect the communication chip 10. The isolation power supply can effectively reduce the impact of external environmental interference on the signal and improve signal quality. However, due to its high functional integration and high production cost, the supply of isolation power supplies on the market is relatively limited. Furthermore, the demand for isolation power supplies is large, resulting in a relatively high market price. The first isolation transformer 201, due to its simple design, low production cost, and relatively abundant supply, has a lower price, and its use significantly reduces system costs.
[0050] Figure 3 Another schematic diagram of the data transmission circuit of this application embodiment is shown. Based on the above embodiment, the RS-485 standard supports multi-point communication and allows multiple nodes to be connected on a bus. Therefore, multiple communication chips 10 can be set in the system. If the number of communication chips 10 is N, where N is a positive integer greater than 1, each communication chip 10 is electrically connected to each external device 40 of the external device group 11 through the transformer isolation module 20. The transformer isolation module 20 is used to isolate each communication chip 10 from each external device 40 of the external device group 11 to protect each communication chip 10.
[0051] Each external device 40 in external device group 11 can be, but is not limited to, various sensors, and can also be other devices. Each external device 40 can be of the same type, or can be of different types. For example, an external device 40 can be a temperature sensor, a humidity sensor, a pressure sensor, etc.
[0052] Understandably, the transformer isolation module 20 may only use a single isolation transformer with at least two sets of primary and secondary windings, such as... Figure 4 As shown, the circuit contains two communication chips 10 (e.g., ...). Figure 4 The two communication chips, U3 and U10, share a common isolation transformer (e.g., U3 and U10). Figure 4The isolation transformer HL3 in the middle has different primary windings and secondary windings. Different primary windings are connected to different communication chips 10, and different secondary windings are connected to different devices. The isolation between different communication chips 10 and different external devices 40 is achieved by using a single isolation transformer.
[0053] The transformer isolation module 20 can also be equipped with multiple isolation transformers. Each isolation transformer can achieve isolation between a single communication chip 10 or multiple communication chips 10 and external devices 40. The configuration can be adjusted according to the actual application. As an example, the transformer isolation module 20 includes N isolation transformers, with each communication chip 10 electrically connected to each external device 40 of the external device group 11 through its respective isolation transformer. Each isolation transformer can achieve isolation between a single communication chip 10 and each external device 40.
[0054] Understandably, the number of communication chips 10 and isolation transformers can be set according to the actual application. If each isolation transformer can achieve isolation between a single communication chip 10 and the external device 40, then the number of communication chips 10 should be the same as the number of isolation transformers, so as to achieve protection for all communication chips 10.
[0055] In the data transmission circuit of this embodiment, multiple isolation transformers are set in the transformer isolation module 20. The multiple isolation transformers protect each 485 communication chip from damage caused by electrical noise and surge voltage. Each isolation transformer can also enhance the signal output by each 485 communication chip, increase the signal transmission distance, and the cost of isolation transformers is low. While ensuring system stability, it also reduces the cost of the system.
[0056] This application also provides a data transmission system, which includes a main controller 30 and the data transmission circuit mentioned in any of the above embodiments.
[0057] Specifically, the main controller 30 communicates with the RS-485 communication chip via an asynchronous transceiver. The asynchronous transceiver provides serial data transmission and reception functions. The main controller 30 initializes the asynchronous transceiver and the RS-485 communication chip, sets the corresponding parameters, and configures the DE / RE pins. When data needs to be transmitted, the main controller 30 sets the DE / RE pins to a high level and returns them to a low level after transmitting the data frame. When data is received, a receive interrupt is triggered on the asynchronous transceiver. The main controller 30 reads and parses the data and executes corresponding logic processing according to the actual application.
[0058] This application also provides a data transmission device, which includes the data transmission system described above.
[0059] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that, in alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.
[0060] In addition, the functional modules or units in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.
[0061] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a smartphone, personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.
[0062] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.
Claims
1. A data transmission circuit, characterized in that, include: A communication chip and a transformer isolation module are provided. One end of the communication chip is used to connect to the main controller, and the other end of the communication chip is electrically connected to one end of the transformer isolation module. The other end of the transformer isolation module is used to connect to external devices. The main controller is used to transmit data with the external device using the communication chip; The transformer isolation module is used to electrically isolate the communication chip from the external device in order to protect the communication chip.
2. The data transmission circuit according to claim 1, characterized in that, The communication chip includes a first port, a second port, and a third port. The first port and the second port are electrically connected to the transformer isolation module, and the third port is electrically connected to the main controller.
3. The data transmission circuit according to claim 2, characterized in that, The transformer isolation module includes a first isolation transformer, the primary winding of which is electrically connected to the first port and the second port, and the secondary winding of which is used to connect to the external device.
4. The data transmission circuit according to claim 1, characterized in that, If the number of the communication chips is N, where N is a positive integer greater than 1, each of the communication chips is electrically connected to each external device in the external device group through the transformer isolation module; The transformer isolation module is used to isolate each of the communication chips from each of the external devices in the external device group, thereby protecting each of the communication chips.
5. The data transmission circuit according to claim 4, characterized in that, The transformer isolation module includes N isolation transformers, and each of the communication chips is electrically connected to each of the external devices in the external device group through the respective isolation transformer.
6. The data transmission circuit according to claim 2, characterized in that, The communication chip is a 485 communication chip.
7. The data transmission circuit according to claim 6, characterized in that, The first port is the positive terminal of the differential signal, and the second port is the negative terminal of the differential signal.
8. The data transmission circuit according to claim 1, characterized in that, The turns ratio of the isolation transformer in the transformer isolation module is 1:
1.
9. A data transmission system, characterized in that, The data transmission system includes the main controller and the data transmission circuit according to any one of claims 1-8.
10. A data transmission device, characterized in that, The data transmission device is equipped with the data transmission system as described in claim 9.