Adaptive input interface circuit

Abstract

The utility model relates to the technical field of interface circuits, in particular to a self-adaptive input interface circuit, which comprises a processing module and an output module. The input end of the processing module receives and processes an external voltage signal, the processed voltage signal is transmitted to the output module, and the output module transmits the received voltage signal to the controller; the processing module comprises a field effect transistor Q13 and a voltage stabilizing resistor R54, and the voltage stabilizing resistor is connected between a grid electrode G and a source electrode S of the field effect transistor. The beneficial effects of the utility model are that the circuit can adapt to a wide voltage signal range from 5V to 24V, and through the design of the optocoupler and the 150-ohm resistor, the current flowing through the optocoupler is ensured to be constant at 5mA and is not influenced by the change of external input voltage; therefore, the circuit can work stably under different voltage levels, electronic equipment is effectively protected from being influenced by voltage fluctuation, meanwhile, the circuit design is simplified, and the reliability and practicability of the circuit are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of interface circuit, especially a self -adaptation input interface circuit. BACKGROUND

[0002] Now various electronic products need to carry out signal interaction, and the most simple interaction mode is still high low level signal, and many industrial occasions use different voltage grade signals, such as 24V, 12V, 9V, 6V etc., but the voltage of the access of the existing controller is specific, for example 5V.

[0003] The existing interface circuit cannot adapt to voltage input of different ranges. Therefore, it is particularly important to design a circuit that can be compatible with different voltage signals, can adapt to various input voltage signals, and can protect electronic equipment. SUMMARY

[0004] This part is to summarize some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this part and the abstract of the specification and the utility model name to avoid obscuring the purpose of this part, the abstract of the specification and the utility model name, and such simplifications or omissions cannot be used to limit the scope of the utility model.

[0005] In view of the above or the problem that multiple voltage inputs cannot be compatible in the prior art, the utility model is proposed.

[0006] Therefore, the purpose of the utility model is to provide a self -adaptation input interface circuit.

[0007] To solve the above technical problems, the utility model provides the following technical scheme: a self -adaptation input interface circuit, a processing module and an output module; the input end of the processing module receives external voltage signal and processes, and the processed voltage signal is transmitted to the output module, and the output module transmits the received voltage signal to the controller.

[0008] As a preferred scheme of the self -adaptation input interface circuit of the utility model, wherein: the processing module includes field effect tube Q13, voltage stabilizing resistor R54, and the voltage stabilizing resistor R54 is connected between the gate G and the source S of the field effect tube.

[0009] As a preferred scheme of the self -adaptation input interface circuit of the utility model, wherein: the drain D of the field effect tube is connected with input interface terminal GPIO_IN1P.

[0010] As a preferred scheme of the self -adaptation input interface circuit of the utility model, wherein: the drain D and the gate G of the field effect tube are connected with working resistor R88.

[0011] As a preferred scheme of the adaptive input interface circuit of the utility model, wherein: the output module includes photoelectric coupler U12, the pin 1 of photoelectric coupler U12 is connected with the source S of field effect tube through voltage stabilizing resistance R54, the pin 2 of photoelectric coupler U12 is connected with input interface terminal GPIO_IN1N.

[0012] As a preferred scheme of the adaptive input interface circuit of the utility model, wherein: the pin 3 of photoelectric coupler U12 is grounded, the pin 4 of photoelectric coupler U12 is connected with power supply VCC through pull-up resistance R66, and the pin 4 of photoelectric coupler U12 is also connected with the base of triode Q9.

[0013] As a preferred scheme of the adaptive input interface circuit of the utility model, wherein: the pin 1 and the pin 2 of photoelectric coupler U12 are also connected with connecting resistance R87.

[0014] As a preferred scheme of the adaptive input interface circuit of the utility model, wherein: the emitter of triode Q9 is grounded, and the collector of triode Q9 is connected with the input end of controller.

[0015] As a preferred scheme of the adaptive input interface circuit of the utility model, wherein: the triode Q9 and the input end of controller are also connected with power supply VCC through current-limiting resistance R74.

[0016] As a preferred scheme of the adaptive input interface circuit of the utility model, wherein: the input interface terminal GPIO_IN1P and the input interface terminal GPIO_IN1N are connected with capacitor C56

[0017] The utility model has the advantages that the utility model can adapt to the wide voltage signal range of 5V~24V, through the design of photoelectric coupler and 150 ohm resistance, the current flowing through the photoelectric coupler is ensured to be constant at 5mA, and is not affected by external input voltage variation; the circuit can stably work under different voltage grades, effectively protects electronic equipment from the influence of voltage fluctuation, simplifies the circuit design, and improves the reliability and practicality of the circuit. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical scheme of the embodiment of the utility model, the drawings needed to be used in the embodiment description will be briefly introduced below, and obviously, the drawings in the following description are only some embodiments of the utility model, and those skilled in the art can also obtain other drawings according to these drawings without paying the creativity labor intensity. Among them:

[0019] Figure 1 It is the circuit schematic diagram of the utility model. DETAILED DESCRIPTION

[0020] In order to make the above objectives, features and advantages of the present application more apparent, a detailed description of the specific embodiments of the present application will be given below with reference to the accompanying drawings.

[0021] In the following description, a lot of specific details are set forth in order to facilitate a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present application, therefore the present application is not limited to the specific embodiments disclosed below.

[0022] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. In this specification, "in one embodiment" does not mean the same embodiment, nor is it an independent or alternative embodiment that excludes other embodiments.

[0023] Embodiment 1

[0024] Referring to Figure 1 For the first embodiment of the present application, the embodiment provides an adaptive input interface circuit, which can realize the effect of adapting to 5-24V voltage input, which comprises a processing module 100 and an output module 200. The input voltage signal is processed by setting the processing module 100, and the input voltage signal can be any voltage value signal in 5-24V. The current flowing through the voltage stabilizing resistor R54 is about 5mA, so that the current value flowing into the output module 200 is always maintained at a certain value, which can drive the processing module 100, so that the controller detects the external input signal.

[0025] Specifically, the input end of the processing module 100 receives and processes the external voltage signal, and transmits the processed voltage signal to the output module 200, and the output module 200 transmits the received voltage signal to the controller.

[0026] Among them, the input end of the output module 200 is electrically connected with the processing module 100, and the output end of the output module 200 is electrically connected with the processing module 100; the processing module 100 processes the flowing voltage signal, and then transmits to the controller through the output module 200, so that when the voltage signal is in the range of 5-24V, the internal controller can detect the external input signal; when the voltage signal is lower than 5V, the internal controller does not detect the external input signal.

[0027] The operation process is as follows: the external voltage signal is input into the processing module 100 through the interface terminal, and the current flowing out of the processing module 100 is always stabilized at about 5 mA through the processing of the processing module 100, and the processed signal flows into the output module 200, and the controller detects the external input signal through the output module 200.

[0028] Therefore, by arranging the processing module 100 and the output module 200, the voltage signal range of 5-24 V can be converted into a signal suitable for processing by the controller.

[0029] Embodiment 2

[0030] Reference Figure 1 The second embodiment of the utility model is different from the previous embodiment, and further optimization of the adaptive input interface circuit is provided, and the problem of how to convert the voltage signal is solved, and the processing module 100 comprises a field effect tube Q13 and a voltage stabilizing resistor R54, and the gate G and the source S of the field effect tube are connected with the voltage stabilizing resistor. The voltage signal input from outside is converted into a signal suitable for processing by the internal controller by arranging the field effect tube Q13, and the voltage stabilizing resistor R54 is used to calculate the voltage between the two ends of Vgs. By the processing of the field effect tube Q13, the current flowing through the voltage stabilizing resistor R54 is always stabilized at about 5 mA, and the voltage between the two ends of Vgs is stabilized at about -0.7 V, and the field effect tube Q13 in the utility model is a junction field effect tube.

[0031] The drain D of the field effect tube is connected with the input interface terminal GPIO_IN1P. In the utility model, the resistance value of the voltage stabilizing resistor R54 is 150 Ω, and the resistance value of the connecting resistor R87 is 10 kΩ; the voltage stabilizing resistor R54 is used to calculate the voltage between the two ends of the gate G and the source S of the field effect tube. The interface terminal GPIO_IN1P and the interface terminal GPIO_IN1N are used to connect the external voltage signal, and the external voltage signal is input into the field effect tube, and the external voltage signal is converted into a signal suitable for processing by the controller.

[0032] Specifically, the working resistor R88 is connected between the drain D and the gate G of the field effect tube. The voltage stabilizing resistor R54 is 150 Ω. The resistance value of the working resistor R88 is 10 kΩ; after the external voltage signal is input, the connecting resistor R87 and the working resistor R88 generate a current I2, the value of I2 is 0.5-2 mA, the current flowing into the voltage stabilizing resistor R54 is I1, the sum of I1 and I2 is I3, I3 is the current value of the input and output module 200, and is about 5 mA-7 mA, which meets the working current requirement of the output module 200. The value of the external input voltage signal changes, and the drain D and the source S of the field effect tube always remain at 5 mA, and do not change obviously with the change of the external input voltage.

[0033] Working process: The external voltage signal is input into the field effect tube through the interface terminal GPIO_IN1P and the interface terminal GPIO_IN1N, the input voltage signal is converted into a signal suitable for the controller, and the processed voltage signal is transmitted to the controller through the output module 200.

[0034] In summary, by arranging the field effect tube and the voltage stabilizing resistor R54, the input 5-24V signal is converted into a signal suitable for the controller.

[0035] Embodiment 3

[0036] Reference Figure 1 For the third embodiment of the utility model, different from the previous embodiment, the embodiment provides a self-adaptive input interface circuit, solves the problem of how to adapt to different range voltage signals, and includes an output module 200 including an optoelectronic coupler U12, a pin 1 of the optoelectronic coupler U12 is connected to the source S of the field effect tube through a voltage stabilizing resistor R54, and a pin 2 of the optoelectronic coupler U12 is connected to the input interface terminal GPIO_IN1N. By arranging the optoelectronic coupler U12, the internal controller can be protected from the influence of external voltage fluctuations or noise, and the compatibility and safety of the circuit are improved. The triode Q9 is used as an electronic switch, and the on-off state between the collector and the emitter is controlled by changing the current state of the base. The pull-up resistor R66 limits the current flowing through the optoelectronic coupler U12, preventing the current from being too large and damaging the optoelectronic coupler U12 or other circuit elements.

[0037] Specifically, the pin 3 of the optoelectronic coupler U12 is grounded, the pin 4 of the optoelectronic coupler U12 is connected to the power supply VCC through the pull-up resistor R66, and the pin 4 of the optoelectronic coupler U12 is also connected to the base of the triode Q9. The emitter of the triode Q9 is grounded, and the collector of the triode Q9 is connected to the input end of the controller. When the pin 1 and the pin 2 of the optoelectronic coupler U12 are conductive, the pin 3 and the pin 4 of the optoelectronic coupler U12 are conductive, the base of the triode Q9 is grounded, and the triode Q9 is not conductive; when the pin 1 and the pin 2 of the optoelectronic coupler U12 are not conductive, the pin 3 and the pin 4 of the optoelectronic coupler U12 are not conductive, the base of the triode Q9 is connected to the power supply VCC, the power supply VCC is 3.3V, and the triode Q9 is conductive.

[0038] Further, the pin 1 and the pin 2 of the optoelectronic coupler U12 are connected across the connecting resistor R87. When the input voltage signal is lower than 5V, the optoelectronic coupler U12 cannot be driven, so that the pin 1 and the pin 2 of the optoelectronic coupler U12 are not conductive; when the input voltage signal is in the range of 5-24V, the optoelectronic coupler U12 can be driven, so that the pin 1 and the pin 2 of the optoelectronic coupler U12 are conductive.

[0039] Further, the triode Q9 and the controller input terminal are also connected to the power supply VCC through the current limiting resistor R74. The power supply VCC is 3.3V, and the current limiting resistor R74 limits the current flowing through the optocoupler U12 to prevent the optocoupler U12 or other circuit elements from being damaged by excessive current. When the triode Q9 is turned on, the input terminal of the controller is grounded, and no external input signal is detected. When the triode Q9 is not turned on, the input terminal of the controller is connected to the power supply VCC, a high-level signal is input to the controller, and the controller can detect the external input signal.

[0040] Preferably, a capacitor C56 is connected between the interface terminal GPIO_IN1P and the interface terminal GPIO_IN1N. The capacitor C56 is used to perform noise reduction processing on the externally input voltage signal.

[0041] Operation process: The external voltage signal is input to the field effect transistor through the interface terminal GPIO_IN1P and the interface terminal GPIO_IN1N, the input voltage signal is converted into a signal suitable for the controller, and the processed signal is transmitted to the optocoupler U12. When the input signal is in the range of 5-24V, the pins 1 and 2 of the optocoupler U12 are turned on, the pins 3 and 4 of the optocoupler U12 are turned on, the base of the triode Q9 is grounded, the triode Q9 is not turned on, the input terminal of the controller is connected to the power supply VCC, and the controller input terminal detects a high-level signal. When the input signal is lower than 5V, the pins 1 and 2 of the optocoupler U12 are not turned on, the pins 3 and 4 of the optocoupler U12 are not turned on, the base of the triode Q9 is connected to the power supply VCC, the triode Q9 is turned on, the input terminal of the controller is grounded, and the controller input terminal does not detect a voltage signal.

[0042] In summary, it can adapt to a wide range of voltage signals of 5V-24V, and through the design of the optocoupler and the 150-ohm resistor, the current flowing through the optocoupler is ensured to be constant at 5mA, which is not affected by the change of the external input voltage.

[0043] It is important to note that the construction and arrangement of the application shown in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review the present disclosure will readily appreciate that many modifications can be made to the embodiments without departing from the spirit and scope of the application as described in the claims. For example, the order in which steps are performed can be changed, or other steps can be added, omitted, or modified. Accordingly, all such modifications are intended to be included within the scope of the present application. The application is meant to encompass all techniques and structures that are the same as or similar to those described in this disclosure, and alternatives and modifications that are apparent to those skilled in the art are intended to be encompassed by the present claims. The claims should not be limited to the embodiments set forth in the specific written description and the drawings, but can include any other embodiments that fall within the scope of the present application as defined by the claims.

[0044] Furthermore, in order to provide a concise description of the exemplary embodiments, not all features of an actual implementation can be described.

[0045] It should be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions can be made. Such development efforts can be complex and time-consuming, but can also benefit from the teachings of this disclosure. These efforts can also be susceptible to change, modification, and equiva lence, and it should be understood that a variety of specific implementation decisions can be made that result in an apparently different, but functionally equivalent implementation.

[0046] It should be noted that the above-mentioned embodiments are only used to illustrate the technical solutions of the present application, not limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or equivalently replaced without departing from the spirit and scope of the present application, and they should be included in the scope of the claims of the present application.

Claims

1. An adaptive input interface circuit, characterized by: The application relates to a voltage signal processing circuit, which comprises a processing module (100) and an output module (200). An input end of the processing module (100) receives an external voltage signal and processes the voltage signal, and the processed voltage signal is transmitted to the output module (200); the output module (200) transmits the received voltage signal to a controller. The processing module (100) comprises a field effect tube Q13 and a voltage stabilizing resistor R54, and the voltage stabilizing resistor R54 is connected between a gate G and a source S of the field effect tube.

2. The self-adapting input interface circuit of claim 1, wherein: A drain D of the field effect tube is connected to an input interface terminal GPIO_IN1P.

3. The self-adapting input interface circuit of claim 2, wherein: A working resistor R88 is connected between the drain D and the gate G of the field effect tube.

4. The self-adapting input interface circuit of claim 3, wherein: The output module (200) comprises an optoelectronic coupler U12, a pin 1 of the optoelectronic coupler U12 is connected to the source S of the field effect tube through the voltage stabilizing resistor R54, and a pin 2 of the optoelectronic coupler U12 is connected to the input interface terminal GPIO_IN1N.

5. The self-adapting input interface circuit of claim 4, wherein: A pin 3 of the optoelectronic coupler U12 is grounded, a pin 4 of the optoelectronic coupler U12 is connected to a power supply VCC through a pull-up resistor R66, and the pin 4 of the optoelectronic coupler U12 is also connected to a base of a triode Q9.

6. The self-adapting input interface circuit of claim 5, wherein: A connecting resistor R87 is further connected between the pin 1 and the pin 2 of the optoelectronic coupler U12.

7. The self-adapting input interface circuit of claim 6, wherein: An emitter of the triode Q9 is grounded, and a collector of the triode Q9 is connected to an input end of the controller.

8. The self-adapting input interface circuit of claim 6, wherein: The triode Q9 and the input end of the controller are further connected to the power supply VCC through a current-limiting resistor R74.

9. The self-adapting input interface circuit of claim 8, wherein: A capacitor C56 is connected between the input interface terminal GPIO_IN1P and the input interface terminal GPIO_IN1N.

10. The self-adapting input interface circuit of claim 9, wherein: ​

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