A circuit for driving multiple RGBs using a small number of IO ports

Abstract

The utility model relates to electronic drive technical field, specifically disclose a kind of circuit of using small amount IO mouth drive multiple RGB, respectively to RGB output by parallel output branch, realize the connection of multistage RGB by extended output branch, realize the function of driving multiple RGB by small amount IO mouth, using PWM port respectively open break to control RGB, can realize more accurate current control, to ensure the uniformity of LED display in RGB. And when the RGB area used is large enough, 8 even more LEDs can be driven, with strong adaptability, can meet the needs of various different application scenarios, solve the problem that traditional microcontroller usually only has limited PWM port, limits the number of RGB driven.

Description

Technical Field

[0001] This application relates to the field of electronic drive technology, and specifically discloses a circuit that uses a small number of I / O ports to drive multiple RGB chips. Background Technology

[0002] RGB display technology is an emerging display technology with advantages such as high brightness, long lifespan, and energy efficiency, and is widely used in various display devices. The key to RGB display technology lies in the design of the driving circuit. How to drive as many RGB values ​​as possible with minimal resources (such as I / O ports and power supplies) while ensuring uniformity of display effect is an important research direction in the field of RGB display technology.

[0003] In existing technologies, the driving of RGB display technology includes electronic driving and microcontroller control. Microcontroller technology, as a crucial component of RGB display technology, primarily functions by generating PWM signals to control the brightness of RGB elements, thereby enabling image display. However, traditional microcontrollers typically have only a limited number of PWM ports, which restricts the number of RGB elements they can drive.

[0004] This invention provides a circuit that uses a small number of I / O ports to drive multiple RGB chips, in order to solve the above-mentioned problems. Utility Model Content

[0005] The purpose of this invention is to solve the problem that traditional microcontrollers typically have only a limited number of PWM ports, which restricts the number of RGB signals they can drive.

[0006] To achieve the above objectives, the basic solution of this utility model provides a circuit that drives multiple RGB chips using a small number of I / O ports. The circuit includes a microcontroller with integrated LIN, several input circuits connected to the PWM ports of the microcontroller with integrated LIN, a total output circuit connected in series with the input circuits, and a power supply. The total output circuit includes several parallel output branches that are powered by the RGB chips respectively. The output includes an amplification electrode connected to the RGB chips. The amplification electrode includes an input coupling part, a transistor amplification part, and an output part connected to the RGB chips.

[0007] Furthermore, the transistor constant current circuit includes a fourth transistor, a fourth resistor, and a thirty-seventh capacitor. The fourth transistor is a PNP transistor. The base of the fourth transistor is connected to the seventh resistor. The emitter of the fourth transistor is connected to the positive terminal of the power supply VS. The collector of the fourth transistor is connected to the total output circuit. The fourth resistor and the thirty-seventh capacitor are connected in parallel between the emitter and base of the fourth transistor.

[0008] Furthermore, a ninth capacitor for stabilizing the voltage and a thirty-first resistor for limiting the current are connected in parallel between the positive terminal of the power supply and ground.

[0009] Furthermore, the input coupling section includes an input coupling resistor and an input coupling capacitor; the transistor amplification section includes an amplifying transistor and an amplifying capacitor; the input coupling resistor and the input coupling capacitor are connected in parallel between the collector of the fourth transistor and the collector of the amplifying transistor; the amplifying capacitor is connected in parallel between the collector and the emitter of the amplifying transistor; the output section includes an output transistor and an output resistor; the output resistor is connected in series between the emitter of the amplifying transistor and the emitter of the output transistor and grounded; the base of the amplifying transistor is connected in parallel to ground; the base of the output transistor is connected in series with the collector of the amplifying transistor; and the collector of the output transistor is connected to RGB. Both the amplifying transistor and the output transistor are NPN transistors.

[0010] Furthermore, the microcontroller's PWM port output frequency is 1kHz and the duty cycle is 50%.

[0011] The principle and effect of this solution are as follows:

[0012] Compared to existing technologies, this invention uses parallel output branches to output to RGB LEDs separately, achieving multi-level RGB connectivity through extended output branches. This enables driving multiple RGB LEDs with a small number of I / O ports. By using PWM ports to control the RGB LEDs individually, more precise current control is achieved, ensuring the uniformity of the RGB LED display. Furthermore, when the RGB area is large enough, it can drive eight or more LEDs, offering strong adaptability to meet the needs of various application scenarios. This solves the problem of traditional microcontrollers typically having only a limited number of PWM ports, which restricts the number of RGB LEDs they can drive. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This diagram illustrates a circuit that uses a small number of I / O ports to drive multiple RGB chips, according to an embodiment of this application. Detailed Implementation

[0015] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.

[0016] A circuit that uses a small number of I / O ports to drive multiple RGB chips, implemented as follows: Figure 1 As shown:

[0017] It includes a microcontroller with integrated LIN, several input circuits connected to the PWM ports of the microcontroller with integrated LIN, a total output circuit connected in series with the input circuits, and a power supply. The total output circuit includes several parallel output branches that are powered by RGB respectively.

[0018] The input circuit includes a seventh resistor connected in series with the PWM port and a transistor constant current circuit connected in series with the seventh resistor.

[0019] The transistor constant current circuit includes a fourth transistor, a fourth resistor, and a thirty-seventh capacitor. The fourth transistor is a PNP transistor. The base of the fourth transistor is connected to the seventh resistor, and the emitter of the fourth transistor is connected to the positive terminal of the power supply VS. The collector of the fourth transistor is connected to the total output circuit. The fourth resistor and the thirty-seventh capacitor are connected in parallel between the emitter and base of the fourth transistor.

[0020] In this embodiment, a 10uF ninth capacitor and a 10kΩ thirty-first resistor are connected in parallel between the positive terminal of the power supply and ground to achieve voltage regulation and current limiting. Among them, the seventh resistor and the ninth capacitor form a high-frequency bypass to shunt high-frequency interference to ground; the seventh resistor and the thirty-first resistor form a voltage divider parallel structure, which together determine the static potential of the base of the fourth transistor.

[0021] In this embodiment, the microcontroller with integrated LIN has three PWM ports, which are connected to three sets of input circuits and corresponding total output circuits.

[0022] like Figure 1 As shown, the total output circuit includes four parallel output branches, each of which includes an amplifier connected to RGB.

[0023] Taking the first output branch with output signal CTR_R1 as an example, the amplification stage includes an input coupling section, a transistor amplification section, and an output section connected to RGB. The input coupling section includes an input coupling resistor (the first resistor) and an input coupling capacitor (the twenty-fourth capacitor). The transistor amplification section includes an amplifying transistor (the seventh transistor) and an amplifying capacitor (the second capacitor). The input coupling resistor and input coupling capacitor are connected in parallel between the collector of the fourth transistor and the collector of the amplifying transistor. The amplifying capacitor is connected in parallel between the collector and emitter of the amplifying transistor. The output section includes an output transistor (the first transistor) and an output resistor (the eighth resistor). The output resistor is connected in series between the emitters of the amplifying transistor and the output transistor and grounded. The base of the amplifying transistor is connected in parallel to ground. The base of the output transistor is connected in series with the collector of the amplifying transistor. The collector of the output transistor is connected to RGB and outputs the signal CTR_R1.

[0024] The connection structure of the other three output branches is the same as that of the first output branch.

[0025] In this embodiment, the microcontroller's PWM port output frequency is 1kHz and the duty cycle is 50%.

[0026] When this application is used, the parallel output branches output to RGB respectively, and the multi-level RGB connection is realized through the extended output branches, so as to realize the function of driving multiple RGB with a small number of IO ports.

[0027] Meanwhile, this application uses PWM ports to control RGB separately, enabling more precise current control and ensuring the uniformity of the LED display in the RGB. Furthermore, when the RGB area used is large enough, it can drive eight or even more LEDs, offering strong adaptability and meeting the needs of various application scenarios.

[0028] Furthermore, this application avoids the complexity of traditional analog circuit design, reduces design difficulty, and also reduces production and maintenance costs. The control method is simple and easy to implement; if more LEDs need to be driven, only a corresponding transistor constant current circuit needs to be added, without changing the original design, facilitating system expansion and upgrades.

[0029] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A circuit for driving multiple RGBs using a small number of IO ports, characterized in that, It includes a microcontroller with integrated LIN, several input circuits connected to the PWM ports of the microcontroller with integrated LIN, a total output circuit connected in series with the input circuits, and a power supply. The total output circuit includes several parallel output branches that are powered by RGB respectively. The output includes an amplification electrode connected to RGB. The amplification electrode includes an input coupling part, a transistor amplification part, and an output part connected to RGB.

2. The circuit of claim 1, wherein, The transistor constant current circuit includes a fourth transistor, a fourth resistor, and a thirty-seventh capacitor. The fourth transistor is a PNP transistor. The base of the fourth transistor is connected to the seventh resistor. The emitter of the fourth transistor is connected to the positive terminal of the power supply VS. The collector of the fourth transistor is connected to the total output circuit. The fourth resistor and the thirty-seventh capacitor are connected in parallel between the emitter and base of the fourth transistor.

3. The circuit of claim 2, wherein, A ninth capacitor for stabilizing the voltage and a thirty-first resistor for limiting the current are also connected in parallel between the positive terminal of the power supply and ground.

4. The circuit of claim 2, wherein, The input coupling section includes an input coupling resistor and an input coupling capacitor. The transistor amplification section includes an amplifying transistor and an amplifying capacitor. The input coupling resistor and the input coupling capacitor are connected in parallel between the collector of the fourth transistor and the collector of the amplifying transistor. The amplifying capacitor is connected in parallel between the collector and the emitter of the amplifying transistor. The output section includes an output transistor and an output resistor. The output resistor is connected in series between the emitter of the amplifying transistor and the emitter of the output transistor and is grounded. The base of the amplifying transistor is connected in parallel to ground. The base of the output transistor is connected in series with the collector of the amplifying transistor. The collector of the output transistor is connected to RGB. Both the amplifying transistor and the output transistor are NPN transistors.

5. The circuit of claim 1, wherein, The microcontroller's PWM port output frequency is 1kHz with a duty cycle of 50%.

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