LED display state control circuit
By combining the main chip and multiple GPIO ports with NPN transistors, the design solves the problem of insufficient flexibility in existing LED display circuits, realizes flexible control of multiple LEDs, improves system expandability and the richness of displayed information, and protects the LEDs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-04
- Publication Date
- 2026-03-20
AI Technical Summary
Existing LED display circuits lack flexibility and scalability, making it impossible to achieve flexible LED display control. In particular, when controlling multiple LEDs, a single GPIO may not be sufficient.
The main chip generates control signals, which are combined with NPN transistors through multiple GPIO ports to achieve independent control of multiple LEDs. The LEDs are controlled by connecting them to the power supply through current-limiting resistors. The control circuit design includes multiple NPN transistors and current-limiting resistors to protect the LEDs.
It enables flexible control of multiple LEDs, improves the system's scalability and the diversity of displayed information, protects LEDs from damage caused by excessive current, and extends their service life.
Smart Images
Figure CN224020429U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to LED control circuit technical field, concretely is a kind of LED display state control circuit. BACKGROUND
[0002] LED display circuit usually adopts two methods: one is that LED is directly connected to power line, another is that through single GPIO, single or a group of LED is controlled.When LED is directly connected to power line, system power LED is directly bright, power LED is extinguished, cannot be done flexible regulation and control, the information that can be shown is less.While through single GPIO, single or a group of LED is controlled, although it can be designed GPIO control response by software, the effect of this control mode is usually fixed, it is difficult to realize flexible change.In addition, when needing to control multiple LED, single GPIO can not be enough to cope with, limit the expansibility of system. SUMMARY
[0003] The utility model provides a kind of LED display state control circuit to realize flexible LED display control in view of the technical problems existing in prior art.
[0004] The technical scheme that the utility model solves above-mentioned technical problem is as follows:
[0005] Provide a kind of LED display state control circuit, the control circuit includes:
[0006] Main chip, for generating control signal;
[0007] Multiple GPIO ports, set in the main chip, for outputting the control signal;
[0008] LED control circuit, with multiple the GPIO port electric connection, receives the control signal and adjusts the bright and dark state of LED according to the control signal;
[0009] Multiple LED, with the LED control circuit electric connection, responds the control signal of the LED control circuit to show different information;
[0010] The LED control circuit includes multiple NPN triodes, the base of each NPN triode is electrically connected with one of the GPIO port respectively, the collector of each NPN triode is electrically connected with the anode of one of the LED respectively, the emitter of each NPN triode is grounded;Multiple the cathode of the LED is electrically connected with power supply through current-limiting resistance.
[0011] More further, first GPIO port and second GPIO port in multiple the GPIO port are electrically connected with the base of first NPN triode and second NPN triode respectively.
[0012] When the first GPIO port outputs high level and the second GPIO port outputs low level, the first NPN triode is turned on, the second NPN triode is turned off, the first LED connected with the collector of the first NPN triode is lighted, and the second LED connected with the collector of the second NPN triode is not lighted.
[0013] Further, the first GPIO port and the second GPIO port in the plurality of GPIO ports are electrically connected with the base of the first NPN triode and the second NPN triode respectively.
[0014] When the first GPIO port outputs low level and the second GPIO port outputs high level, the second NPN triode is turned on, the first NPN triode is turned off, the second LED connected with the collector of the second NPN triode is lighted, and the first LED connected with the collector of the first NPN triode is not lighted.
[0015] Further, when the first GPIO port and the second GPIO port in the plurality of GPIO ports output low level at the same time, the first NPN triode and the second NPN triode are both turned off, and the first LED connected with the collector of the first NPN triode and the second LED connected with the collector of the second NPN triode are both not lighted.
[0016] Further, the control circuit further comprises a plurality of current-limiting resistors, one end of each of the current-limiting resistors is electrically connected with the negative electrode of one of the LEDs, and the other end is electrically connected with the power supply, for limiting the current flowing through the LED, so as to prevent the LED from being damaged due to excessive current.
[0017] Further, the main chip is a microcontroller, the microcontroller generates the control signals through programming, and outputs the control signals through the plurality of GPIO ports, so as to realize flexible control of the plurality of LEDs.
[0018] The beneficial effects of the present application are as follows:
[0019] The present application provides an LED display state control circuit with more flexibility. By using the combination of a plurality of GPIO ports and NPN triodes, independent control of a plurality of LEDs is realized. Specifically, the main chip outputs control signals through a plurality of GPIO ports, and these signals are transmitted to each LED through NPN triodes, so that the on-off state of each LED can be flexibly controlled. Not only the expansibility of the system is improved, but also the information displayed by the LED is more diverse. Figure 2As shown, when GPIO1 is pulled high and GPIO2 is pulled low, Q1 and Q4 are turned on, Q2 and Q3 are turned off, so that LED1 is lighted and LED2 is not lighted; on the contrary, when GPIO1 is pulled low and GPIO2 is pulled high, Q2 and Q3 are turned on, Q1 and Q4 are turned off, so that LED1 is not lighted and LED2 is lighted. In addition, by increasing more GPIO ports and corresponding triodes, the control range can be further expanded, more diversified display effects are realized, and the problem of insufficient flexibility in the traditional circuit is solved. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1 A circuit diagram of the utility model;
[0021] Figure 2 A principle schematic view of the utility model. DETAILED DESCRIPTION
[0022] In order to make the purpose, technical scheme and advantages of the utility model more clear and intelligible, the utility model is further described in detail below by combining with the drawings and examples. The examples of the examples are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The examples described below by referring to the drawings are exemplary and are only used to explain the utility model, and cannot be understood as limiting the utility model. In addition, it should be understood that the specific examples described herein are only used to explain the utility model and cannot be used to limit the utility model.
[0023] In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features limited by "first", "second" can be explicitly or implicitly included one or more of the features. In the description of the utility model, the meaning of "a plurality of" is two or more than two, unless otherwise specifically limited.
[0024] In the description of the utility model, it should be pointed out that, unless otherwise specifically specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium, or the communication between two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.
[0025] The disclosure below provides many different embodiments or examples for implementing various aspects of the present application. Although each of the various embodiments described below with respect to a particular example includes a specific set of features, not all of these features are required in all embodiments of the application. In addition, it should be understood that the various embodiments described herein are not limited to the specific examples described below, but include any and all alternatives, modifications, equivalents, and combinations thereof. Furthermore, the disclosure provides various examples of specific processes and materials, but it should be understood that other processes and / or materials can be used.
[0026] Reference is made to Figure 1 and Figure 2 The present application provides the following preferred embodiments:
[0027] Embodiment One
[0028] To solve the problem of insufficient flexibility in the existing LED display circuit, the present embodiment proposes a design of LED display state control circuit. Specifically, the control circuit includes a main chip, a plurality of GPIO ports, an LED control circuit, and a plurality of LEDs.
[0029] Further, the main chip is used to generate control signals, which are output through the plurality of GPIO ports provided on the main chip. The main chip can be a microcontroller or other types of processors, and its main function is to generate and output control signals. Further, the LED control circuit is electrically connected with the plurality of GPIO ports, receives the control signals and adjusts the on-off state of the LEDs according to the control signals. The LED control circuit includes a plurality of NPN triodes, the base of each NPN triode is electrically connected with a GPIO port respectively, the collector of each NPN triode is electrically connected with the positive electrode of an LED respectively, and the emitter of each NPN triode is grounded. The negative electrodes of the plurality of LEDs are electrically connected with the power supply through current-limiting resistors.
[0030] It should be understood that this design allows each GPIO port to independently control an LED through the corresponding NPN triode. When a certain GPIO port outputs a high level, the corresponding NPN triode is turned on, thereby causing the LED connected with the collector of the NPN triode to light up; when a certain GPIO port outputs a low level, the corresponding NPN triode is turned off, thereby causing the LED connected with the collector of the NPN triode to be extinguished. This design not only improves the scalability of the system, but also makes the LED display more diverse and rich in information.
[0031] Further, the selection of the current-limiting resistor is also a key factor. The current-limiting resistor functions to limit the current flowing through the LED, preventing the LED from being damaged due to excessive current. The resistance value of the current-limiting resistor can be selected according to the specific LED model and operating voltage to ensure that the LED operates within a safe operating range.
[0032] It can be understood that through this design, the system can flexibly control the on-off state of multiple LEDs, thereby achieving more diversified display effects. For example, when different information needs to be displayed, only the control signal output by the main chip needs to be changed through programming, and the on-off combination of different LEDs can be achieved, thereby displaying the required information.
[0033] The benefit of this embodiment is that by using a combination of multiple GPIO ports and NPN transistors, independent control of multiple LEDs is achieved, improving the scalability and flexibility of the system, making the LED display information more diverse.
[0034] Embodiment Two
[0035] To solve the problem of insufficient flexibility in existing LED display circuits, this embodiment further refines the connection method of the first GPIO port and the second GPIO port with the NPN transistor. Specifically, the first GPIO port and the second GPIO port in the multiple GPIO ports are respectively electrically connected to the base of the first NPN transistor and the second NPN transistor.
[0036] Further, when the first GPIO port outputs a high level and the second GPIO port outputs a low level, the first NPN transistor is turned on and the second NPN transistor is turned off. At this time, the first LED connected to the collector of the first NPN transistor is on, and the second LED connected to the collector of the second NPN transistor is not on. This design allows the system to achieve different display states of two LEDs through simple logic control.
[0037] Further, the selection of the first NPN transistor and the second NPN transistor is also very important. Common NPN transistors such as 2N2222 or BC547 can be selected, which have a low saturation voltage drop and a high current gain, suitable for such control circuits. It should be understood that the base-emitter voltage (Vbe) of the NPN transistor is usually about 0.6V, so when the GPIO port outputs a high level, the base-emitter voltage is sufficient to turn on the transistor; when the GPIO port outputs a low level, the base-emitter voltage is not sufficient to turn on the transistor, thereby achieving control of the LED.
[0038] It can be understood that through this design, the system can flexibly control the on-off state of the two LEDs. For example, when a specific information needs to be displayed, only by changing the control signal output by the main chip through programming, different display states of the two LEDs can be realized. This design not only improves the flexibility of the system, but also makes the displayed information more diversified.
[0039] Embodiment three
[0040] In order to solve the problem of insufficient flexibility in the existing LED display circuit, the embodiment further refines the connection mode of the first GPIO port and the second GPIO port with the NPN transistor. Specifically, the first GPIO port and the second GPIO port in the plurality of GPIO ports are electrically connected with the base of the first NPN transistor and the second NPN transistor respectively.
[0041] Further, when the first GPIO port outputs low level and the second GPIO port outputs high level, the second NPN transistor is turned on and the first NPN transistor is cut off. At this time, the second LED connected with the collector of the second NPN transistor is on, and the first LED connected with the collector of the first NPN transistor is not on. This design enables the system to realize different display states of the two LEDs through simple logic control.
[0042] Further, the model selection of the first NPN transistor and the second NPN transistor is also very important. Common NPN transistors such as 2N2222 or BC547 can be selected, which have lower saturation voltage drop and higher current gain, and are suitable for such control circuit. It should be understood that the base-emitter voltage (Vbe) of the NPN transistor is usually about 0.6V, so when the GPIO port outputs high level, the base-emitter voltage is sufficient to turn on the transistor; when the GPIO port outputs low level, the base-emitter voltage is not enough to turn on the transistor, thereby realizing the control of the LED.
[0043] Embodiment four
[0044] In order to solve the problem of insufficient flexibility in the existing LED display circuit, the embodiment further refines the case where the first GPIO port and the second GPIO port output low level at the same time. Specifically, when the first GPIO port and the second GPIO port in the plurality of GPIO ports output low level at the same time, the first NPN transistor and the second NPN transistor are both cut off, and the first LED connected with the collector of the first NPN transistor and the second LED connected with the collector of the second NPN transistor are both not on.
[0045] Further, when the first GPIO port and the second GPIO port output low level at the same time, the base-emitter voltage (Vbe) of the first NPN transistor and the second NPN transistor is not enough to turn them on, so both transistors are in the off state. At this time, the first LED connected to the collector of the first NPN transistor and the second LED connected to the collector of the second NPN transistor have no current passing through, so they are not lit. This design enables the system to achieve the full-off state of the two LEDs through simple logic control.
[0046] It needs to be understood that this design not only simplifies the control logic of the circuit, but also improves the reliability of the system. For example, in some application scenarios, all LEDs may need to be turned off to represent a certain specific state. By programming the control signals output by the main chip, this function can be easily realized.
[0047] Embodiment Five
[0048] To solve the problem of insufficient flexibility in existing LED display circuits, this embodiment further optimizes the design of current-limiting resistors. Specifically, the control circuit further includes a plurality of current-limiting resistors, one end of each current-limiting resistor is electrically connected to the negative electrode of an LED, and the other end is electrically connected to the power supply, for limiting the current flowing through the LED to prevent the LED from being damaged due to excessive current.
[0049] Further, the main function of the current-limiting resistor is to limit the current flowing through the LED to ensure that the LED operates within a safe operating range. The resistance value of the current-limiting resistor can be selected according to the specific LED model and operating voltage. For example, if the operating voltage of the LED is 2V and the power supply voltage is 5V, the resistance value of the current-limiting resistor can be calculated by the following formula: R = (Vcc - V led ) / I led , where Vcc is the power supply voltage, V led is the operating voltage of the LED, and I led is the operating current of the LED. Assuming I led is 20mA, the resistance value of the current-limiting resistor is 150Ω.
[0050] It needs to be understood that the selection of the current-limiting resistor not only considers the operating parameters of the LED, but also considers the overall power consumption of the circuit. A proper current-limiting resistor can ensure the stable operation of the LED while reducing unnecessary power consumption. In addition, the current-limiting resistor can also protect the circuit from excessive current impact and prolong the service life of the circuit.
[0051] It can be understood that through this design, the system can effectively protect the LED from being damaged by excessive current. For example, when a certain GPIO port outputs a high level, the corresponding NPN transistor is turned on, and the LED is lit. At this time, the current limiting resistor limits the current flowing through the LED, ensuring that the LED operates within a safe operating range. This design not only improves the reliability of the system, but also prolongs the service life of the LED.
[0052] Through this embodiment, the system can effectively protect the LED from being damaged by excessive current, improving the reliability and service life of the system.
[0053] Embodiment six
[0054] To solve the problem of insufficient flexibility in existing LED display circuits, the design of the main chip is further optimized in this embodiment. Specifically, the main chip is a microcontroller, which generates control signals through programming and outputs the control signals through multiple GPIO ports to achieve flexible control of multiple LEDs.
[0055] Further, the selection of the microcontroller is also very critical. Common microcontrollers such as STM32, Arduino or PIC can be selected, which have rich GPIO resources and powerful processing capabilities, suitable for such control circuits. The microcontroller generates control signals through programming, which are output through GPIO ports to achieve independent control of multiple LEDs. It should be understood that the programming of the microcontroller can be realized by C language or other high-level languages, and the programming content mainly includes generating control signals and configuring GPIO ports.
[0056] Further, the microcontroller can also communicate with other devices through external interfaces to realize more complex control logic. For example, it can communicate with the host computer through a serial interface to receive instructions sent by the host computer, thereby realizing remote control. This design makes the system not only able to run independently, but also can be integrated with other systems to realize more complex functions.
[0057] The beneficial effects of the present application are embodied in the above-mentioned preferred embodiments of the present application, and are not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included within the scope of protection of the present application.
Claims
1. An LED display status control circuit, characterized in that, The control circuit includes: The main chip is used to generate control signals; Multiple GPIO ports are provided on the main chip for outputting the control signals; The LED control circuit is electrically connected to multiple GPIO ports, receives the control signal, and adjusts the on / off state of the LED according to the control signal. Multiple LEDs are electrically connected to the LED control circuit and respond to control signals from the LED control circuit to display different information. The LED control circuit includes multiple NPN transistors. The base of each NPN transistor is electrically connected to one of the GPIO ports, the collector of each NPN transistor is electrically connected to the positive terminal of one of the LEDs, and the emitter of each NPN transistor is grounded. The negative terminals of the multiple LEDs are electrically connected to the power supply through current-limiting resistors.
2. The LED display status control circuit as described in claim 1, characterized in that, The first GPIO port and the second GPIO port among the plurality of GPIO ports are electrically connected to the bases of the first NPN transistor and the second NPN transistor, respectively. When the first GPIO port outputs a high level and the second GPIO port outputs a low level, the first NPN transistor is turned on and the second NPN transistor is turned off. The first LED connected to the collector of the first NPN transistor lights up, and the second LED connected to the collector of the second NPN transistor does not light up.
3. The LED display status control circuit as described in claim 1, characterized in that, The first GPIO port and the second GPIO port among the plurality of GPIO ports are electrically connected to the bases of the first NPN transistor and the second NPN transistor, respectively. When the first GPIO port outputs a low level and the second GPIO port outputs a high level, the second NPN transistor is turned on, the first NPN transistor is turned off, the second LED connected to the collector of the second NPN transistor lights up, and the first LED connected to the collector of the first NPN transistor does not light up.
4. The LED display status control circuit as described in claim 2, characterized in that, When the first GPIO port and the second GPIO port among the multiple GPIO ports output a low level at the same time, both the first NPN transistor and the second NPN transistor are turned off, and neither the first LED connected to the collector of the first NPN transistor nor the second LED connected to the collector of the second NPN transistor lights up.
5. The LED display status control circuit as described in claim 1, characterized in that, The control circuit also includes multiple current-limiting resistors. One end of each current-limiting resistor is electrically connected to the negative electrode of one of the LEDs, and the other end is electrically connected to the power supply. These resistors are used to limit the current flowing through the LEDs to prevent the LEDs from being damaged due to excessive current.
6. The LED display status control circuit as described in claim 1, characterized in that, The main chip is a microcontroller. The microcontroller generates the control signals through programming and outputs the control signals through multiple GPIO ports to achieve flexible control of multiple LEDs.