Control circuit for LED display screen

Abstract

The utility model discloses a control circuit for an LED display screen, and belongs to the technical field of LED display screen control. Comprising a serial interface, the input end of a displacement register module is connected with a display module in an LED display screen through the serial interface, the output end of the displacement register module is connected with the input end of a counting module, and the counting module is used for slowing down data output by the displacement register module. The output of the counting module is simultaneously connected with the input end of the single voltage stabilization trigger module and the input end of the inverting module, under the action of the single voltage stabilization trigger module, the period is reset, the inverting module is matched to enable data and clock signals to be in one-to-one correspondence, and the output end of the single voltage stabilization trigger module is connected with the serial interface. And the output end of the anti-phase module is connected with the serial interface. According to the utility model, the use of an expensive FPGA chip is avoided, and the complexity of software is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of LED display control, and particularly relates to a control circuit for an LED display screen. Background Art

[0002] An LED display screen is a complex system composed of multiple display units that can be combined and spliced and an appropriate controller. Its main components include a metal structure frame, display units, a scanning control board, a switching power supply, transmission cables, a control circuit, a dedicated display card and a multimedia card, a computer and its peripherals, etc. The control circuit precisely controls the current, adjusts the brightness, controls the scanning, and processes the image data of the light-emitting diodes in the LED display screen to ensure its normal operation and high-quality image display.

[0003] At present, the vast majority of LED display control units on the market are divided into two types. One is to use an FPGA chip, which is used in full-color LED display screens, that is, multi-channel data lines are controlled in parallel; the other is to use a single-chip microcomputer, which is used in monochromatic LED display screens, that is, usually a single data line is used for folded-line control. However, using an FPGA has problems such as high price and high software threshold, and using a single-chip microcomputer has problems such as the need for folded-line control of the LED driving unit and high complexity in the cooperation between software and the driving unit. To solve the above problems, the utility model proposes a control circuit for an LED display screen. Summary of the Utility Model

[0004] Purpose of the utility model: To provide a control circuit for an LED display screen, which solves the above problems existing in the prior art.

[0005] Technical solution: A control circuit for an LED display screen includes a serial interface. The input end of a shift register module is connected to a display module in the LED display screen through the serial interface. The output end of the shift register module is connected to the input end of a counting module. The counting module is used to slow down the data output by the shift register module. The output of the counting module is simultaneously connected to the input end of a single-stable trigger module and the input end of an inverter module. Under the action of the single-stable trigger module, the reset period is reset, and in cooperation with the inverter module, the data is made to correspond one-to-one with the clock signal. The output end of the single-stable trigger module is connected to the serial interface, and the output end of the inverter module is connected to the serial interface.

[0006] Preferably, the displacement register module includes chip U9, chip U10, capacitor C14, capacitor C15, resistor R12, and resistor R20. Pin 14 of chip U9 is connected to the serial interface and resistor R12 at the same time. One end of capacitor C14 is connected to pin 13 of chip U9, and the other end is connected to pin 16 of chip U9. Pin 9 of chip U9 is connected to resistor R20 and pin 14 of chip U10 at the same time. One end of capacitor C15 is connected to pin 13 of chip U10, and the other end is connected to pin 16 of chip U10. Pin 12 of chip U9 is connected to pin 12 of chip U10.

[0007] Preferably, the counting module includes chip U6, resistor R17, resistor R18, resistor R19, and capacitor C20. Pin 11 of chip U6 is connected to the output end of the displacement register module. Pin 5 of chip U6 is connected to the input end of the inverting module. One end of resistor R19 is connected to pin 14 of chip U6, and the other end is grounded. One end of capacitor C20 is connected to pin 16 of chip U6, and the other end is connected to pin 8 of chip U6. One end of resistor R17 is connected to pin 6 of chip U6. The other end of resistor R17 is connected to resistor R18 and the input end of the monostable trigger module at the same time. One end of resistor R18 is connected to pin 7 of chip U6. Chip U6 outputs 8-divided frequency data in cooperation with resistor R17 and outputs 16-divided frequency data in cooperation with resistor R18.

[0008] Preferably, the monostable trigger module includes chip U7, capacitor C17, capacitor C18, and resistor R16. One end of resistor R16 is connected to pin 8 of chip U7. The other end of resistor R16 is connected to pin 7 of chip U7 and one end of capacitor C18 at the same time. The other end of capacitor C18 is connected to pin 6 of chip U7. One end of capacitor C17 is connected to pin 3 of chip U7, and the other end of capacitor C17 is grounded.

[0009] Preferably, the inverting module includes inverter chip U8 and capacitor C19. One end of capacitor C19 is connected to the pin of inverter U8, and the other end of capacitor C19 is grounded. Among them, the inverter chip U8 uses an inverter chip of model NL27WZ04.

[0010] Preferably, both chip U9 and chip U10 use chips of model 74HC595.

[0011] Preferably, chip U6 uses a chip of model 74HC193.

[0012] Preferably, chip U7 uses a chip of model SN74LVC1G123.

[0013] Beneficial effects: The present utility model relates to a control circuit for an LED display screen. Only an ordinary 74HC595 type chip is required, and by cooperating with a counting module, a voltage stabilizing trigger module, and an inverting module to perform frequency division processing on data and clocks, it can achieve dividing 1 SPI into 8 parallel data or dividing 1 SPI into 16 parallel data. While avoiding the use of expensive FPGA chips, it reduces the complexity of software. Brief Description of the Drawings

[0014] Figure 1 It is the control circuit diagram of the present utility model. Detailed Embodiment

[0015] As Figure 1 shown, the present utility model provides a technical solution: A control circuit for an LED display screen includes a serial interface, a shift register module, a counting module, a single voltage stabilizing trigger module, and an inverting module. The input end of the shift register module is connected to the display module in the LED display screen through the serial interface, the output end of the shift register module is connected to the input end of the counting module, the counting module is used to slow down the data output by the shift register module, the output of the counting module is simultaneously connected to the input end of the single voltage stabilizing trigger module and the input end of the inverting module. Under the action of the single voltage stabilizing trigger module, the reset period is reset, and in cooperation with the inverting module, the data and the clock signal are made to correspond one by one. The output end of the single voltage stabilizing trigger module is connected to the serial interface, and the output end of the inverting module is connected to the serial interface. Among them, the shift register module includes chip U9, chip U10, capacitor C14, capacitor C15, resistor R12, and resistor R20. Pin 14 of chip U9 is simultaneously connected to the serial interface and resistor R12. One end of capacitor C14 is connected to pin 13 of chip U9, and the other end is connected to pin 16 of chip U9. Pin 9 of chip U9 is simultaneously connected to resistor R20 and pin 14 of chip U10. One end of capacitor C15 is connected to pin 13 of chip U10, and the other end is connected to pin 16 of chip U10. Pin 12 of chip U9 is connected to pin 12 of chip U10. Both chip U9 and chip U10 use 74HC595 type chips. By using an ordinary 74HC595 type chip, and cooperating with a counting module, a voltage stabilizing trigger module, and an inverting module to perform frequency division processing on data and clocks, it can achieve dividing 1 SPI into 8 parallel data or dividing 1 SPI into 16 parallel data. While avoiding the use of expensive FPGA chips, it reduces the complexity of software.

[0016] In a further embodiment, the counting module includes a chip U6, a resistor R17, a resistor R18, a resistor R19, and a capacitor C20. The chip U6 is a 74HC193 type chip. The pin 11 of the chip U6 is connected to the output end of the displacement register module. The pin 5 of the chip U6 is connected to the input end of the inverting module. One end of the resistor R19 is connected to the pin 14 of the chip U6, and the other end is grounded. One end of the capacitor C20 is connected to the pin 16 of the chip U6, and the other end is connected to the pin 8 of the chip U6. One end of the resistor R17 is connected to the pin 6 of the chip U6, and the other end of the resistor R17 is simultaneously connected to the resistor R18 and the input end of the monostable trigger module. One end of the resistor R18 is connected to the pin 7 of the chip U6. The chip U6 outputs 8-divided frequency data in cooperation with the resistor R17 and outputs 16-divided frequency data in cooperation with the resistor R18. The monostable trigger module includes a chip U7, a capacitor C17, a capacitor C18, and a resistor R16. The chip U7 is an SN74LVC1G123 type chip. One end of the resistor R16 is connected to the pin 8 of the chip U7, and the other end of the resistor R16 is simultaneously connected to the pin 7 of the chip U7 and one end of the capacitor C18. The other end of the capacitor C18 is connected to the pin 6 of the chip U7. One end of the capacitor C17 is connected to the pin 3 of the chip U7, and the other end of the capacitor C17 is grounded. The inverting module includes an inverter chip U8 and a capacitor C19. One end of the capacitor C19 is connected to the pin of the inverter U8, and the other end of the capacitor C19 is grounded. Among them, the inverter chip U8 is an NL27WZ04 type inverter chip.

[0017] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the protection scope of the present invention.

Claims

1. A control circuit for an LED display screen, characterized in that: It includes a serial interface, through which the input end of the displacement register module is connected to the display module in the LED display screen, the output end of the displacement register module is connected to the input end of the counting module, the counting module is used to slow down the data output by the displacement register module, the output of the counting module is simultaneously connected to the input end of the single voltage-stabilizing trigger module and the input end of the inverting module, under the action of the single voltage-stabilizing trigger module, the cycle is reset, and the inverting module is cooperated to make the data and the clock signal correspond one by one, the output end of the single voltage-stabilizing trigger module is connected to the serial interface, and the output end of the inverting module is connected to the serial interface.

2. A control circuit for an LED display screen according to claim 1, characterized in that: The displacement register module includes chip U9, chip U10, capacitor C14, capacitor C15, resistor R12 and resistor R20. Pin 14 of the chip U9 is connected to the serial interface and resistor R12 at the same time. One end of the capacitor C14 is connected to pin 13 of the chip U9, and the other end is connected to pin 16 of the chip U9. Pin 9 of the chip U9 is connected to resistor R20 and pin 14 of the chip U10 at the same time. One end of the capacitor C15 is connected to pin 13 of the chip U10, and the other end is connected to pin 16 of the chip U10. Pin 12 of the chip U9 is connected to pin 12 of the chip U10.

3. A control circuit for an LED display screen according to claim 1, characterized in that: The counting module includes a chip U6, a resistor R17, a resistor R18, a resistor R19 and a capacitor C20. Pin 11 of the chip U6 is connected to the output end of the displacement register module, pin 5 of the chip U6 is connected to the input end of the inverting module, one end of the resistor R19 is connected to pin 14 of the chip U6, and the other end thereof is grounded, one end of the capacitor C20 is connected to pin 16 of the chip U6, and the other end thereof is connected to pin 8 of the chip U6, one end of the resistor R17 is connected to pin 6 of the chip U6, and the other end of the resistor R17 is simultaneously connected to resistor R18 and the input end of the single voltage-stabilizing trigger module, one end of the resistor R18 is connected to pin 7 of the chip U6, the chip U6 cooperates with resistor R17 to output 8-division data, and the chip U6 cooperates with resistor R18 to output 16-division data.

4. A control circuit for an LED display screen according to claim 1, characterized in that: The single-voltage-stabilized trigger module includes a chip U7, a capacitor C17, a capacitor C18 and a resistor R16, one end of the resistor R16 is connected to pin 8 of the chip U7, the other end of the resistor R16 is simultaneously connected to pin 7 of the chip U7 and one end of the capacitor C18, the other end of the capacitor C18 is connected to pin 6 of the chip U7, one end of the capacitor C17 is connected to pin 3 of the chip U7, and the other end of the capacitor C17 is grounded.

5. The control circuit for an LED display screen according to claim 1, characterized in that: The inverting module includes an inverter chip U8 and a capacitor C19, one end of the capacitor C19 is connected to a pin of the inverter U8, and the other end of the capacitor C19 is grounded, wherein the inverter chip U8 is an inverter chip of model NL27WZ04.

6. A control circuit for an LED display screen according to claim 2, characterized in that: The chip U9 and the chip U10 are both 74HC595 chips.

7. A control circuit for an LED display screen according to claim 3, characterized in that: The chip U6 is a 74HC193 chip.

8. A control circuit for an LED display screen according to claim 4, characterized in that: The chip U7 adopts the SN74LVC1G123 chip.

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