IO port expansion circuit based on microcontroller

Abstract

The utility model discloses an IO port expansion circuit based on a microcontroller. The interface expansion circuit is connected with the microcontroller, so that the number of IO ports of the microcontroller is effectively increased, and the problem that the IO ports of an existing microcontroller are insufficient in the prior art is solved. Meanwhile, a stable power supply is provided for the microcontroller and the interface expansion circuit through the power supply circuit, the reliability and stability of the system are ensured, and the performance problem caused by unstable power supply in an existing expansion scheme is avoided. Besides, the scheme of the utility model is simple in structure and easy to implement, and avoids the defects of complex design and high power consumption of a traditional expansion circuit, thereby improving the real-time performance and stability while simplifying the system design, and effectively solving the problems of design complexity and reliability in the prior art.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic devices, and particularly relates to an IO port expansion circuit based on a microcontroller. Background Art

[0002] In the development process of modern electronic products, the microcontroller (MCU) is widely used as the core control component. However, with the increasing complexity of product functions, the system's demand for input / output (IO) ports has gradually increased. Usually, existing microcontroller models have a fixed number of IO ports and cannot meet the expansion requirements of multiple IO in some scenarios. To solve this problem, external expansion circuits are usually introduced in the prior art to increase the number of IO ports. However, this solution often faces problems such as complex hardware design and high power consumption. Especially in some small embedded systems, traditional expansion methods may increase the system's design cost and development difficulty.

[0003] In addition, existing multiple-IO expansion schemes often require additional control logic or complex programming, which affects the real-time performance and reliability of the system. Therefore, how to expand IO ports under limited hardware resources while ensuring system stability and simplifying the design remains an important issue. Summary of the Utility Model

[0004] Therefore, the embodiment of the utility model provides an IO port expansion circuit based on a microcontroller to solve the problem that existing multiple-IO expansion schemes often require additional control logic or complex programming, which affects the real-time performance and reliability of the system.

[0005] To achieve the above object, the embodiment of the utility model provides the following technical solutions:

[0006] An IO port expansion circuit based on a microcontroller includes a microcontroller, an interface expansion circuit, an output display circuit, and a power supply circuit;

[0007] The input end of the interface expansion circuit is connected to the microcontroller, and the output end of the interface expansion circuit is the output end of the extended IO port of the microcontroller;

[0008] The input end of the output display circuit is connected to the microcontroller;

[0009] The input end of the power supply circuit is connected to a power supply, and the output end of the power supply circuit is respectively connected to the power supply ends of the microcontroller and the interface expansion circuit.

[0010] Optionally, the microcontroller is an STM32F407ZET6 microcontroller.

[0011] Optionally, the interface expansion circuit includes a 74HC574PW118 flip-flop.

[0012] Optionally, the first pin and the tenth pin of the 74HC574PW118 flip-flop are both grounded; the second pin, the third pin, the fourth pin, the fifth pin, the sixth pin, the seventh pin, the eighth pin and the ninth pin of the 74HC574PW118 flip-flop are connected to the tenth pin, the eleventh pin, the twelfth pin, the thirteenth pin, the fourteenth pin, the fifteenth pin, the eighteenth pin and the nineteenth pin of the microcontroller; the eleventh pin of the 74HC574PW118 flip-flop is connected to the fourth pin of the microcontroller; the twelfth pin, the thirteenth pin, the fourteenth pin, the fifteenth pin, the sixteenth pin, the seventeenth pin, the eighteenth pin and the nineteenth pin of the 74HC574PW118 flip-flop are respectively the output terminals of the extended IO ports of the microcontroller; the twentieth pin of the 74HC574PW118 flip-flop is grounded through the twenty-fourth capacitor C24.

[0013] Optionally, the output display circuit includes a plurality of output display units, and the number of the plurality of output display units corresponds one-to-one to the number of the output terminals of the extended IO ports of the microcontroller.

[0014] Optionally, the output display unit includes a pull-up resistor and a light-emitting diode. The first end of the pull-up resistor is connected to the voltage output terminal VCC_JDQ, the second end of the pull-up resistor is connected to the positive electrode of the light-emitting diode, and the negative electrode of the light-emitting diode is connected to the microcontroller.

[0015] Optionally, the power supply circuit includes a first voltage conversion circuit and a second voltage conversion circuit;

[0016] The input end of the first voltage conversion circuit is connected to the power supply, the output end of the first voltage conversion circuit is respectively connected to the power supply end of the interface expansion circuit and the input end of the second voltage conversion circuit, and the output end of the second voltage conversion circuit is connected to the power supply end of the microcontroller.

[0017] Optionally, the first voltage conversion circuit includes a TPS5450DDAR step-down conversion chip; the second voltage conversion circuit includes an AMS1117-3.3 power chip.

[0018] Optionally, the first pin of the TPS5450DDAR buck conversion chip is connected to the eighth pin of the TPS5450DDAR buck conversion chip through the fifty-fifth capacitor C55; the second, third, and fifth pins of the TPS5450DDAR buck conversion chip are left floating; the fourth pin of the TPS5450DDAR buck conversion chip is divided into two paths, one path is connected to the +5V power output terminal through the one-hundred-and-fiftieth resistor R150, and the other path is grounded through the one-hundred-and-fifty-first resistor R151; the sixth pin of the TPS5450DDAR buck conversion chip is grounded; the seventh pin of the TPS5450DDAR buck conversion chip is divided into two paths, one path is connected to the +24V power output terminal, and the other path is grounded through the sixty-fourth capacitor C64; the eighth pin of the TPS5450DDAR buck conversion chip is divided into two paths, one path is connected to one end of the second inductor L2, and the other path is connected to the cathode of the eighty-first diode D81;

[0019] The other end of the second inductor L2 is divided into five paths. The first path is connected to one end of the fifty-sixth capacitor C56, the second path is connected to one end of the fifty-seventh capacitor C57, the third path is connected to one end of the fifty-eighth capacitor C58, the fourth path is connected to the cathode of the seventh diode T7, and the fifth path is the +5V power output terminal;

[0020] The other ends of the fifty-sixth capacitor C56, the fifty-seventh capacitor C57, the fifty-eighth capacitor C58, the anode of the seventh diode T7, and the anode of the eighty-first diode D81 are all grounded.

[0021] Optionally, the first pin of the AMS1117-3.3 power chip is grounded; the second pin of the AMS1117-3.3 power chip is connected to the fourth pin of the AMS1117-3.3 power chip; the third pin of the AMS1117-3.3 power chip is divided into two paths, one path is connected to the +5V power output terminal, and the other path is grounded through the sixty-fifth capacitor C65; the fourth pin of the AMS1117-3.3 power chip is divided into seven paths. The first path is connected to one end of the sixtieth capacitor C60, the second path is connected to one end of the sixty-sixth capacitor C66, the third path is connected to one end of the sixty-second capacitor C62, the fourth path is connected to the cathode of the eighth diode T8, the fifth path is connected to one end of the sixty-first capacitor C61, the sixth path is connected to one end of the sixty-third capacitor C63, and the seventh path is the +3.3V power output terminal;

[0022] The other ends of the sixtieth capacitor C60, the sixty-sixth capacitor C66, the sixty-second capacitor C62, the anode of the eighth diode T8, the other end of the sixty-first capacitor C61, and the other end of the sixty-third capacitor C63 are all grounded.

[0023] The utility model has at least the following beneficial effects:

[0024] The utility model provides an IO port expansion circuit based on a microcontroller. By connecting the interface expansion circuit to the microcontroller, the number of IO ports of the microcontroller is effectively increased, and the problem of insufficient IO ports of the existing microcontroller in the background technology is solved. At the same time, the present application provides a stable power supply for the microcontroller and the interface expansion circuit through the power supply circuit, ensuring the reliability and stability of the system and avoiding the performance problems caused by unstable power supply in the existing expansion schemes. In addition, the solution of the present application has a simple structure and is easy to implement, avoiding the defects of complex design and high power consumption of the traditional expansion circuit. Thus, while simplifying the system design, the real-time performance and stability are improved, and the problems of design complexity and reliability in the background technology are effectively solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the prior art and the present utility model, the drawings required for describing the prior art and the embodiments of the present utility model will be briefly introduced below. Obviously, the drawings in the following description are only exemplary, and those of ordinary skill in the art can also obtain other drawings derived from the provided drawings without creative efforts.

[0026] The structures, ratios, sizes, etc. illustrated in this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present utility model. Any modification of the structure, change of the proportional relationship or adjustment of the size should still fall within the scope covered by the technical content disclosed in the present utility model without affecting the effects that the present utility model can produce and the purposes that can be achieved.

[0027] Figure 1 It is a circuit principle block diagram of an IO port expansion circuit based on a microcontroller provided by an embodiment of the present utility model;

[0028] Figure 2 It is a circuit schematic diagram of a microcontroller provided by an embodiment of the present utility model;

[0029] Figure 3 It is a circuit schematic diagram of an interface expansion circuit provided by an embodiment of the present utility model;

[0030] Figure 4 It is a circuit schematic diagram of an output display circuit provided by an embodiment of the present utility model;

[0031] Figure 5 It is a circuit schematic diagram of a first voltage conversion circuit provided by an embodiment of the present utility model;

[0032] Figure 6 This is the circuit schematic diagram of a second voltage conversion circuit provided by an embodiment of the present invention. Specific embodiments

[0033] In order to make the objectives, technical solutions and advantages of the present application more clear and understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0034] In the description of the present invention, unless otherwise specified, "a plurality of" means two or more. The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above-mentioned drawings are intended to distinguish the objects being referred to. For a solution with a time sequence process, such a term expression does not necessarily need to be understood as describing a specific order or sequence. For a solution of a device structure, such a term expression also does not distinguish the importance level, positional relationship, etc.

[0035] In addition, the terms "comprising", "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily need to be limited to those steps or units that have been clearly listed, but may also include other steps or units that are inherent to these processes, methods, products or devices although not clearly listed, or steps or units added based on further optimized solutions conceived by the present invention.

[0036] As Figure 1 shown, an IO port expansion circuit based on a microcontroller includes a microcontroller, an interface expansion circuit, an output display circuit and a power supply circuit;

[0037] The input end of the interface expansion circuit is connected to the microcontroller, and the output end of the interface expansion circuit is the output end of the expanded IO port of the microcontroller;

[0038] The input end of the output display circuit is connected to the microcontroller;

[0039] The input end of the power supply circuit is connected to a power supply, and the output end of the power supply circuit is respectively connected to the power supply terminals of the microcontroller and the interface expansion circuit.

[0040] In this embodiment, the microcontroller is an STM32F407ZET6 microcontroller.

[0041] In this embodiment, the interface expansion circuit includes a 74HC574PW118 flip-flop.

[0042] In this embodiment, the first pin and the tenth pin of the 74HC574PW118 flip-flop are both grounded; the second pin, the third pin, the fourth pin, the fifth pin, the sixth pin, the seventh pin, the eighth pin and the ninth pin of the 74HC574PW118 flip-flop are connected to the tenth pin, the eleventh pin, the twelfth pin, the thirteenth pin, the fourteenth pin, the fifteenth pin, the eighteenth pin and the nineteenth pin of the microcontroller; the eleventh pin of the 74HC574PW118 flip-flop is connected to the fourth pin of the microcontroller; the twelfth pin, the thirteenth pin, the fourteenth pin, the fifteenth pin, the sixteenth pin, the seventeenth pin, the eighteenth pin and the nineteenth pin of the 74HC574PW118 flip-flop are respectively the output terminals of the extended IO port of the microcontroller; the twentieth pin of the 74HC574PW118 flip-flop is grounded through the twenty-fourth capacitor C24.

[0043] In this embodiment, the output display circuit includes a plurality of output display units, and the number of the plurality of output display units corresponds one-to-one to the number of output terminals of the extended IO port of the microcontroller.

[0044] In this embodiment, the output display unit includes a pull-up resistor and a light-emitting diode. The first end of the pull-up resistor is connected to the voltage output terminal VCC_JDQ, the second end of the pull-up resistor is connected to the positive electrode of the light-emitting diode, and the negative electrode of the light-emitting diode is connected to the microcontroller.

[0045] In this embodiment, the power supply circuit includes a first voltage conversion circuit and a second voltage conversion circuit;

[0046] The input end of the first voltage conversion circuit is connected to the power supply, the output end of the first voltage conversion circuit is respectively connected to the power supply terminal of the interface expansion circuit and the input end of the second voltage conversion circuit, and the output end of the second voltage conversion circuit is connected to the power supply terminal of the microcontroller.

[0047] In this embodiment, the first voltage conversion circuit includes a TPS5450DDAR step-down conversion chip; the second voltage conversion circuit includes an AMS1117-3.3 power chip.

[0048] In this embodiment, the first pin of the TPS5450DDAR step-down conversion chip is connected to the eighth pin of the TPS5450DDAR step-down conversion chip through the fifty-fifth capacitor C55; the second, third, and fifth pins of the TPS5450DDAR step-down conversion chip are left floating; the fourth pin of the TPS5450DDAR step-down conversion chip is divided into two paths, one path is connected to the +5V power supply output terminal through the one-hundred-and-fiftieth resistor R150, and the other path is grounded through the one-hundred-and-fifty-first resistor R151; the sixth pin of the TPS5450DDAR step-down conversion chip is grounded; the seventh pin of the TPS5450DDAR step-down conversion chip is divided into two paths, one path is connected to the +24V power supply output terminal, and the other path is grounded through the sixty-fourth capacitor C64; the eighth pin of the TPS5450DDAR step-down conversion chip is divided into two paths, one path is connected to one end of the second inductor L2, and the other path is connected to the cathode of the eighty-first diode D81;

[0049] The other end of the second inductor L2 is divided into five paths. The first path is connected to one end of the fifty-sixth capacitor C56, the second path is connected to one end of the fifty-seventh capacitor C57, the third path is connected to one end of the fifty-eighth capacitor C58, the fourth path is connected to the cathode of the seventh diode T7, and the fifth path is the +5V power supply output terminal;

[0050] The other ends of the fifty-sixth capacitor C56, the fifty-seventh capacitor C57, the fifty-eighth capacitor C58, the anode of the seventh diode T7, and the anode of the eighty-first diode D81 are all grounded.

[0051] In this embodiment, the first pin of the AMS1117-3.3 power chip is grounded; the second pin of the AMS1117-3.3 power chip is connected to the fourth pin of the AMS1117-3.3 power chip; the third pin of the AMS1117-3.3 power chip is divided into two paths, one path is connected to the +5V power supply output terminal, and the other path is grounded through the sixty-fifth capacitor C65; the fourth pin of the AMS1117-3.3 power chip is divided into seven paths. The first path is connected to one end of the sixtieth capacitor C60, the second path is connected to one end of the sixty-sixth capacitor C66, the third path is connected to one end of the sixty-second capacitor C62, the fourth path is connected to the cathode of the eighth diode T8, the fifth path is connected to one end of the sixty-first capacitor C61, the sixth path is connected to one end of the sixty-third capacitor C63, and the seventh path is the +3.3V power supply output terminal;

[0052] The other end of the 60th capacitor C60, the other end of the 66th capacitor C66, the other end of the 62nd capacitor C62, the anode of the eighth diode T8, the other end of the 61st capacitor C61 and the other end of the 63rd capacitor C63 are all grounded.

[0053] The present invention provides an IO port expansion circuit based on a microcontroller. By connecting the interface expansion circuit to the microcontroller, the number of IO ports of the microcontroller is effectively increased, solving the problem of insufficient IO ports of the existing microcontroller in the background art. At the same time, the present application provides a stable power supply for the microcontroller and the interface expansion circuit through the power supply circuit, ensuring the reliability and stability of the system, and avoiding the performance problems caused by unstable power supply in the existing expansion scheme. In addition, the solution of the present application is simple in structure and easy to implement, avoiding the defects of complex design and high power consumption of traditional expansion circuits, thereby simplifying the system design while improving real-time performance and stability, effectively solving the design complexity and reliability problems existing in the background art.

[0054] The overall circuit of this embodiment consists of three parts: To address the problem that the chip has few input and output IO ports, the present invention discloses an extended serial port circuit. This circuit includes three parts: a 74HC574PW chip interface circuit, a power supply circuit, and an output circuit.

[0055] The 74HC574PW chip interface circuit is an octal D-type flip-flop designed using CMOS technology. It consists of eight independent D-type flip-flops and other gate circuits. It features data latching and tri-state outputs. When the clock input, CLK, is high, the outputs respond to input data. When CLK is low, the outputs are latched and maintain their current state, unaffected by inputs. When the output enable, OE, is high, all outputs are in a high-impedance state. When OE is low, all outputs are in a push-pull state. This design uses the microcontroller's PE5 pin to latch and output data.

[0056] Power supply circuit: The 74HC574PW chip uses a 5V power supply, and the chip uses a TPS5450DDAR to step down the input voltage to 5V to power the selected latch. The microcontroller is powered by 3.3V. A stable step-down chip is needed, and the 1117 chip is selected to provide stable power to the microcontroller in order to switch the 74HC574PW chip's CLK pin to output data.

[0057] Output data display circuit: VCC_JDQ provides the pull-up resistor voltage. R116, R117, R118, R119, R120, R121, R122, and R123 are the pull-up resistors for each output data. D55 to D62 are the light-emitting diodes for each path. When the output is low level, the light-emitting diodes will light up. When the output is high level, the light-emitting diodes are in the unlit state.

[0058] As Figures 2 - 6 shown, the circuit board includes: 74HC574PW chip interface circuit, power supply circuit, and output data display circuit.

[0059] This embodiment solves the problem that the built-in input and output pins of the microcontroller are not enough, improves work efficiency, and also reduces the system cost.

[0060] The above-described embodiments only represent the specific implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A microcontroller-based IO port expansion circuit, characterized in that It includes a microcontroller, an interface expansion circuit, an output display circuit, and a power supply circuit; The input end of the interface expansion circuit is connected to the microcontroller, and the output end of the interface expansion circuit is the output end of the extended IO port of the microcontroller; The input end of the output display circuit is connected to the microcontroller; The input end of the power supply circuit is connected to a power supply, and the output end of the power supply circuit is respectively connected to the power supply ends of the microcontroller and the interface expansion circuit.

2. The IO port expansion circuit based on a microcontroller according to claim 1, wherein The microcontroller is an STM32F407ZET6 microcontroller.

3. The IO port expansion circuit based on a microcontroller according to claim 1, wherein The interface expansion circuit includes a 74HC574PW118 flip-flop.

4. The IO port expansion circuit based on a microcontroller according to claim 3, characterized in that, The first pin and the tenth pin of the 74HC574PW118 flip-flop are both grounded; the second pin, the third pin, the fourth pin, the fifth pin, the sixth pin, the seventh pin, the eighth pin, and the ninth pin of the 74HC574PW118 flip-flop are connected to the tenth pin, the eleventh pin, the twelfth pin, the thirteenth pin, the fourteenth pin, the fifteenth pin, the eighteenth pin, and the nineteenth pin of the microcontroller; the eleventh pin of the 74HC574PW118 flip-flop is connected to the fourth pin of the microcontroller; the twelfth pin, the thirteenth pin, the fourteenth pin, the fifteenth pin, the sixteenth pin, the seventeenth pin, the eighteenth pin, and the nineteenth pin of the 74HC574PW118 flip-flop are respectively the output ends of the extended IO port of the microcontroller; the twentieth pin of the 74HC574PW118 flip-flop is grounded through the twenty-fourth capacitor C24.

5. The IO port expansion circuit based on a microcontroller according to claim 1, characterized in that The output display circuit includes a plurality of output display units, and the number of the plurality of output display units corresponds one by one to the number of the output ends of the extended IO port of the microcontroller.

6. The IO port expansion circuit based on a microcontroller according to claim 5, characterized in that The output display unit includes a pull-up resistor and a light-emitting diode. The first end of the pull-up resistor is connected to the voltage output terminal VCC_JDQ, the second end of the pull-up resistor is connected to the positive electrode of the light-emitting diode, and the negative electrode of the light-emitting diode is connected to the microcontroller.

7. The IO port expansion circuit based on a microcontroller according to claim 1, characterized in that The power supply circuit includes a first voltage conversion circuit and a second voltage conversion circuit; The input end of the first voltage conversion circuit is connected to the power supply, the output end of the first voltage conversion circuit is respectively connected to the power supply end of the interface expansion circuit and the input end of the second voltage conversion circuit, and the output end of the second voltage conversion circuit is connected to the power supply end of the microcontroller.

8. The IO port expansion circuit based on a microcontroller according to claim 7, characterized in that, The first voltage conversion circuit includes a TPS5450DDAR buck conversion chip; the second voltage conversion circuit includes an AMS1117-3.3 power chip.

9. A microcontroller-based IO port expansion circuit according to claim 8, characterized in that The first pin of the TPS5450DDAR step-down conversion chip is connected to the eighth pin of the TPS5450DDAR step-down conversion chip via the fifty-fifth capacitor C55; the second, third, and fifth pins of the TPS5450DDAR step-down conversion chip are left floating; the fourth pin of the TPS5450DDAR step-down conversion chip is divided into two paths, one path is connected to the +5V power supply output terminal via the one-hundred-and-fiftieth resistor R150, and the other path is grounded via the one-hundred-and-fifty-first resistor R151; the sixth pin of the TPS5450DDAR step-down conversion chip is grounded; the seventh pin of the TPS5450DDAR step-down conversion chip is divided into two paths, one path is connected to the +24V power supply output terminal, and the other path is grounded via the sixty-fourth capacitor C64; the eighth pin of the TPS5450DDAR step-down conversion chip is divided into two paths, one path is connected to one end of the second inductor L2, and the other path is connected to the cathode of the eighty-first diode D81; The other end of the second inductor L2 is divided into five paths. The first path is connected to one end of the fifty-sixth capacitor C56, the second path is connected to one end of the fifty-seventh capacitor C57, the third path is connected to one end of the fifty-eighth capacitor C58, the fourth path is connected to the cathode of the seventh diode T7, and the fifth path is the +5V power supply output terminal; The other ends of the fifty-sixth capacitor C56, the fifty-seventh capacitor C57, the fifty-eighth capacitor C58, the anode of the seventh diode T7, and the anode of the eighty-first diode D81 are all grounded.

10. An IO port expansion circuit based on a microcontroller according to claim 9, characterized in that, The first pin of the AMS1117-3.3 power supply chip is grounded; the second pin of the AMS1117-3.3 power supply chip is connected to the fourth pin of the AMS1117-3.3 power supply chip; the third pin of the AMS1117-3.3 power supply chip is divided into two paths, one path is connected to the +5V power supply output terminal, and the other path is grounded via the sixty-fifth capacitor C65; the fourth pin of the AMS1117-3.3 power supply chip is divided into seven paths. The first path is connected to one end of the sixtieth capacitor C60, the second path is connected to one end of the sixty-sixth capacitor C66, the third path is connected to one end of the sixty-second capacitor C62, the fourth path is connected to the cathode of the eighth diode T8, the fifth path is connected to one end of the sixty-first capacitor C61, the sixth path is connected to one end of the sixty-third capacitor C63, and the seventh path is the +3.3V power supply output terminal; The other ends of the sixtieth capacitor C60, the sixty-sixth capacitor C66, the sixty-second capacitor C62, the anode of the eighth diode T8, the other end of the sixty-first capacitor C61, and the other end of the sixty-third capacitor C63 are all grounded.

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