LED board card cascade control circuit
By adding CAN bus transceiver chips and terminal impedance matching circuits to the LED transmitting and receiving cards, the problem of cascaded communication control in long-distance multi-LED screen display systems was solved, enabling simple and efficient control of multiple boards and reducing costs.
Patent Information
- Application Number
- CN202520294243.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-24
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-02-24
AI Technical Summary
Existing technologies cannot effectively achieve cascaded communication control between LED sending cards and receiving cards in long-distance multi-LED screen display systems, resulting in complex solutions and high costs.
By employing a CAN bus transceiver chip circuit, a terminal impedance matching circuit, and a CAN bus cascading interface, and by adding a TJA1050T CAN transceiver control chip to the LED transmitting and receiving cards, cascading control between multiple LED transmitting and receiving cards can be achieved.
It realizes cascading communication control between multiple LED sending and receiving cards, which simplifies the solution, reduces costs, and ensures communication stability and flexibility.
Smart Images
Figure CN223956270U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to LED display control technical field, especially a kind of LED board card cascade control circuit. BACKGROUND
[0002] In the application scene of long-distance multi-LED screen display, such as the LED screen used for warning in high-speed rail platform, a super-long LED display screen is laid on the floor of high-speed rail platform, to realize platform information display and overline alarm function, it is necessary to control the LED display screen of about 1km long used for platform warning, to realize platform information corresponding, display warning text, overline alarm, automatic brightness adjustment and other functions, each section of screen must be controlled, and it needs to be cascaded according to one master and multiple slaves. According to the traditional way of existing LED sending card+receiving card, these function requirements cannot be realized, if a sending card is placed in each section of screen, dozens of sending cards may be needed for a platform of 1km long, these dozens of sending cards cannot be cascaded, the scheme will also be more complex, and the cost is too high for customers. CONTENT OF UTILITY MODEL
[0003] The utility model provides a kind of LED board card cascade control circuit, to solve the problem that cascade communication control cannot be realized between LED sending card and receiving card.
[0004] The utility model provides a kind of LED board card cascade control circuit, including CAN bus transceiver chip circuit, terminal impedance matching circuit, CAN bus cascade interface, LED sending card, LED receiving card, the CAN bus transceiver chip circuit includes chip U1, the CAN bus cascade interface includes wiring terminal J1, wiring terminal J2, wiring terminal J1, wiring terminal J2 are respectively provided at both ends of each the LED sending card and each the LED receiving card, the wiring terminal J1 of LED sending card is connected PIN6 pin and PIN 7 pin of chip U1, the wiring terminal J2 of LED sending card is connected the wiring terminal J1 of a LED receiving card, multiple the LED receiving card is cascaded by the butt joint of wiring terminal J1 and wiring terminal J2, the terminal impedance matching circuit is connected PIN 6 pin and PIN 7 pin of chip U1, when the length of CAN bus cascade connection wire exceeds the length that CAN bus transceiver chip circuit itself impedance can match, terminal impedance matching circuit is turned on.
[0005] As a further improvement of the utility model, PIN1 pin and PIN4 pin of chip U1 are respectively connected with the CAN controller of MCU through CAN bus.
[0006] As a further improvement of the utility model, the terminal impedance matching circuit further includes resistance R1, resistance R3 and capacitor C1, one end of the resistance R1 is connected with PIN7 pin of the chip U1, the other end of the resistance R1 is connected with one end of the capacitor C1, one end of the resistance R3 is connected with PIN6 pin of the chip U1, the other end of the resistance R3 is connected with one end of the capacitor C1, and the other end of the capacitor C1 is grounded.
[0007] As a further improvement of the utility model, the terminal impedance matching circuit further includes resistance R1, resistance R3 and capacitor C1, one end of the resistance R1 is connected with PIN7 pin of the chip U1, the other end of the resistance R1 is connected with one end of the capacitor C1, one end of the resistance R3 is connected with PIN6 pin of the chip U1, the other end of the resistance R3 is connected with one end of the capacitor C1, and the other end of the capacitor C1 is grounded.
[0008] As a further improvement of the utility model, when the length of the CAN bus cascade wire exceeds the length that can be matched by the self impedance of the CAN bus transceiver chip circuit, PIN1 pin and PIN2 pin of the wiring terminal J3 are short-circuited through the jumper cap.
[0009] As a further improvement of the utility model, the model of the chip U1 is TJA1050T.
[0010] The utility model has the advantages that: by the distributed real-time control serial communication characteristics of the CAN bus, by increasing 1 CAN transceiver control chip of TJA1050T on the LED sending card and the receiving card, the cascade control between multiple LED sending cards and receiving cards is realized, so that one LED sending card can acquire and issue instructions to control multiple receiving cards through the CAN bus, the function of the cascade communication control of multiple board cards is realized, so that the scheme is more simple, and the cost is more optimal. BRIEF DESCRIPTION OF DRAWINGS
[0011] Figure 1 It is the structure diagram of the utility model LED board card cascade control circuit. DETAILED DESCRIPTION
[0012] In order to make the purpose, technical scheme and advantages of the utility model more clearly, the following is further detailed to the utility model by combining with the drawings and examples.
[0013] As Figure 1The utility model discloses a LED board card cascade control circuit, including CAN bus transceiver chip circuit, terminal impedance matching circuit, CAN bus cascade interface, LED sending card, LED receiving card, CAN bus transceiver chip circuit includes chip U1, CAN bus cascade interface includes wiring terminal J1, wiring terminal J2, and the both ends of each LED sending card and each LED receiving card are provided with wiring terminal J1, wiring terminal J2 respectively, the wiring terminal J1 of LED sending card connects the PIN6 pin and PIN 7 pin of chip U1, the wiring terminal J2 of LED sending card connects the wiring terminal J1 of an LED receiving card, and a plurality of LED receiving cards are cascaded through the butt joint of wiring terminal J1 and wiring terminal J2, and the PIN 6 pin and PIN 7 pin of chip U1 are connected with terminal impedance matching circuit, when the length of CAN bus cascade wiring exceeds the length that CAN bus transceiver chip circuit's own impedance can match, terminal impedance matching circuit is turned on.
[0014] PIN1 pin and PIN4 pin of chip U1 are CAN transceiver signal lines, and PIN7 pin and PIN6 pin are high-low level CAN bus signal lines.
[0015] PIN1 pin and PIN4 pin of chip U1 are CAN transceiver signal lines, and PIN7 pin and PIN6 pin are high-low level CAN bus signal lines.
[0016] PIN1 pin and PIN4 pin of chip U1 are CAN transceiver signal lines, and PIN7 pin and PIN6 pin are high-low level CAN bus signal lines.
[0017] PIN1 pin and PIN4 pin of chip U1 are CAN transceiver signal lines, and PIN7 pin and PIN6 pin are high-low level CAN bus signal lines.
[0018] PIN1 pin and PIN4 pin of chip U1 are CAN transceiver signal lines, and PIN7 pin and PIN6 pin are high-low level CAN bus signal lines.
[0019] The wiring terminal J3 is a 2PIN terminal. The resistors R1, R2, R3 and R4 are all used to parallel a 120Ω resistor between the CAN bus CAN_H and CAN_L, mainly for terminal matching for long distance transmission, to ensure the stability of long distance transmission, wherein the resistors R1 and R3 are reserved, that is, when it is determined that terminal resistors are needed, the resistors R1 and R3 are directly attached, without manual adjustment. The right resistors R2 and R4 are commonly used, and since only the first and last boards need to have a 120Ω terminal matching resistor, the wiring terminal J3 is connected in series between the resistors R2 and R4, to facilitate the connection of the jumper cap of the wiring terminal J3 on the first and last boards during installation.
[0020] Working principle of the LED board card cascade control circuit:
[0021] ① CAN bus transceiver chip circuit part: PIN1 pin and PIN4 pin are CAN transceiver signal lines, mainly responsible for receiving and transmitting data from the MCU CAN controller and CAN bus, PIN7 pin and PIN6 pin are high and low level CAN bus signal lines, mainly through the CAN_H and CAN_L signal lines to cascade multiple LED sending cards and receiving cards on the CAN bus, and each node of the CAN bus can report data through the CAN bus.
[0022] ② Terminal impedance matching circuit part: provides terminal resistance matching for PIN7 pin and PIN6 pin, when the CAN bus cascade connection is relatively long, the 2PIN terminal of the wiring terminal J3 is shorted by the jumper cap, a 120Ω terminal matching resistor is connected in parallel between the CAN_L and CAN_H signal lines, mainly to avoid signal transmission distortion and ensure smooth communication. Whether the terminal resistor is connected needs to be determined according to the actual wiring needs.
[0023] ③ CAN bus cascade interface part: the wiring terminal J1 and the wiring terminal J2 are CAN bus cascade connection terminals, mainly used in the application scenarios of cascading multiple LED sending cards and receiving cards, for example, 1 LED sending card + 10 receiving cards need to be cascaded, the CAN bus connection terminal J1 of the LED sending card is connected to the CAN bus connection terminal J1 of the next receiving card, the CAN bus connection terminal J2 of the next receiving card is connected to the CAN bus connection terminal J1 of the next receiving card, and so on, so that 1 LED sending card and 10 receiving cards can be cascaded on one CAN bus.
[0024] Application of the LED board card cascade control circuit:
[0025] In the application scene of high-speed rail platform warning line LED screen, each section of warning line display screen is controlled by 1 LED sending card + 10 receiving cards, and about 10 sections of warning line display screen are needed for one platform. Through the CAN bus cascading mode of the case, 1 LED sending card + 10 receiving cards are cascaded on one CAN bus, so that 1 LED sending card can be used as a master device to control 10 receiving cards, and the platform information, warning text, overline alarm state feedback, brightness setting and reporting of each section of LED screen can be issued and uploaded through the CAN bus.
[0026] The LED sending card can control each section of receiving card through the CAN bus, and the platform control room can control the warning line LED display screen of the whole platform by controlling 10 LED sending cards. Through the CAN bus cascading mode, the control instruction communication function between the LED sending card and the receiving card is realized, the number of LED sending cards is saved, the cost of the scheme is reduced a lot, and the whole scheme is more simple.
[0027] The application circuit of the LED board card cascading control of the utility model is the distributed real-time control serial communication characteristic of CAN bus, 1 TJA1050T CAN transceiver control chip is added on the LED sending card and the receiving card, the cascading control between multiple LED sending cards and receiving cards is realized, one LED sending card can acquire and issue instructions to control multiple receiving cards through the CAN bus, the function of multiple board card cascading communication control is realized, the scheme is more simple, and the cost is more optimal. The CAN bus cascading communication control scheme of the case can be used for the application scene of multiple LED sending cards + receiving cards for long-distance multi-terminal display screen control, and can be used for the communication between the LED sending cards or the receiving cards, and is compatible with long-distance and short-distance communication control application scene, so that a stable cascading communication control solution is provided for the practical application scene of high-speed rail platform warning line, lamp pole screen and induction screen.
[0028] The above content is a further detailed description of the utility model in combination with the preferred embodiment, and cannot be limited to these descriptions. For ordinary skilled persons in the technical field of the utility model, some simple deductions or substitutions can be made without departing from the concept of the utility model, and all of them should be regarded as belonging to the protection scope of the utility model.
Claims
1. An LED board card cascade control circuit, characterized in that, The application relates to a CAN bus transceiver chip circuit, a terminal impedance matching circuit, a CAN bus cascade interface, an LED sending card and an LED receiving card, wherein the CAN bus transceiver chip circuit comprises a chip U1, the CAN bus cascade interface comprises wiring terminals J1 and J2, each of the LED sending card and the LED receiving card is provided with the wiring terminals J1 and J2 at two ends, the wiring terminal J1 of the LED sending card is connected with PIN6 and PIN7 of the chip U1, the wiring terminal J2 of the LED sending card is connected with the wiring terminal J1 of an LED receiving card, a plurality of the LED receiving cards are cascaded through the connection of the wiring terminals J1 and J2, and the terminal impedance matching circuit is connected with PIN6 and PIN7 of the chip U1.
2. The LED board card cascade control circuit according to claim 1, wherein, PIN1 and PIN4 of the chip U1 are connected with a CAN controller of an MCU through a CAN bus.
3. The LED board card cascade control circuit according to claim 1, wherein, The terminal impedance matching circuit comprises a resistor R2, a resistor R4, a capacitor C2 and a wiring terminal J3, one end of the resistor R2 is connected with PIN7 of the chip U1, the other end of the resistor R2 is connected with one end of the capacitor C2 and PIN2 of the wiring terminal J3, one end of the resistor R4 is connected with PIN6 of the chip U1, the other end of the resistor R4 is connected with PIN1 of the wiring terminal J3, and the other end of the capacitor C2 is grounded.
4. The LED board card cascade control circuit according to claim 3, wherein, The terminal impedance matching circuit further comprises a resistor R1, a resistor R3 and a capacitor C1, one end of the resistor R1 is connected with PIN7 of the chip U1, the other end of the resistor R1 is connected with one end of the capacitor C1, one end of the resistor R3 is connected with PIN6 of the chip U1, the other end of the resistor R3 is connected with one end of the capacitor C1, and the other end of the capacitor C1 is grounded.
5. The LED board card cascade control circuit according to claim 3 or 4, characterized in that, When the length of the CAN bus cascade connection line exceeds the length that can be matched by the self impedance of the CAN bus transceiver chip circuit, PIN1 and PIN2 of the wiring terminal J3 are short-circuited through a jumper cap.
6. The LED board card cascade control circuit according to claim 1, wherein, The model of the chip U1 is TJA1050T.