CN220084961U - Voltage signal amplitude limiting judging device - Google Patents

Abstract

The utility model discloses a voltage signal limiting judgment device, which relates to the technical field of electronic circuits; the device includes: a first filter circuit, a voltage bias circuit, a first comparison circuit, a second comparison circuit, a logic limiting circuit, a third Two filter circuits; wherein, the first input terminal of the first filter circuit receives the input voltage signal, the second input terminal is connected to the transmission terminal of the voltage bias circuit, and the output terminal is respectively connected to the first input terminal of the first comparison circuit and the second filter circuit. The first input terminal of the two comparison circuits is connected; the second input terminal of the first comparison circuit receives the upper amplitude voltage signal; the output terminal of the first comparison circuit is respectively connected to the output terminal of the second comparison circuit, the transmission terminal of the logic limiting circuit, and The input end of the second filter circuit is connected; the output end of the second comparison circuit is connected to the input end of the second filter circuit; the logic limiting circuit is connected to the input end of the second filter circuit; the output end of the second filter circuit is limited Logic level after amplitude judgment.

Description

Voltage signal limiter judgment device

Technical field

The utility model relates to the field of electronic circuits, and in particular to a voltage signal limiting judgment device.

Background technique

This section is intended to provide background or context for the embodiments of the invention set forth in the claims. The description herein is not admitted to be prior art by inclusion in this section.

In the process of using electronic equipment, the electronic equipment needs to operate within a predetermined voltage range. If the voltage provided exceeds the voltage range that the electronic equipment can withstand, it will affect the performance of the electronic equipment and cause the electronic equipment to overheat and burn out. Or damage and other problems, thus affecting the normal operation of electronic equipment. Therefore, it is necessary to limit the voltage signal before inputting it into the electronic equipment.

Therefore, how to provide a voltage signal limiting judgment device with a simple circuit structure and high reliability is an urgent problem that those skilled in the art need to solve.

Utility model content

In an embodiment of the present invention, a voltage signal limiting judgment device is proposed to convert the input voltage signal into a logic level, and judge whether the input voltage signal exceeds the preset voltage limiting range through the logic level, including: a filter circuit, a voltage bias circuit, a first comparison circuit, a second comparison circuit, a logic limiting circuit, and a second filter circuit;

Wherein, the first input terminal of the first filter circuit receives the input voltage signal, the second input terminal of the first filter circuit is connected to the transmission terminal of the voltage bias circuit, and the output terminal of the first filter circuit is respectively connected to the third terminal of the first comparison circuit. An input terminal is connected to the first input terminal of the second comparison circuit; the second input terminal of the first comparison circuit receives the upper amplitude voltage signal; the output terminal of the first comparison circuit is respectively connected to the output terminal and the logic limiter of the second comparison circuit. The transmission end of the amplitude circuit and the input end of the second filter circuit are connected; the second input end of the second comparison circuit receives the lower amplitude limiting voltage signal; the output end of the second comparison circuit is respectively connected to the transmission end of the logic limiting circuit and the second filtering circuit. The input end of the circuit is connected; the transmission end of the logic limiting circuit is connected to the input end of the second filter circuit; the output end of the second filter circuit outputs the logic level after the limiter judgment;

The first filter circuit is used to receive the input voltage signal and filter the positive voltage signal converted by the voltage bias circuit; the voltage bias circuit is used to convert the input voltage signal received by the first filter circuit into a positive voltage signal; the first comparison The circuit is used to receive the upper amplitude voltage signal, compare the upper amplitude voltage signal with the maximum amplitude of the positive voltage signal output by the first filter circuit, and output the first level according to the comparison result; the second comparison circuit is used to receive the lower amplitude voltage signal, Compare the minimum amplitude of the lower limiting voltage signal with the positive voltage signal output by the first filter circuit, and output the second level according to the comparison result; the logic limiting circuit is used to determine the logical relationship between the first level and the second level, and output the logic level; the second filter circuit is used to filter the logic level and output the filtered logic level.

Further, the first filter circuit includes: a first resistor, a third resistor, a first capacitor, and a second capacitor;

Wherein, the first end of the first resistor is the first input end of the first filter circuit, the second end of the first resistor is connected to the first end of the third resistor and the first end of the first capacitor respectively, and the first end of the first resistor is connected to the first end of the first resistor. The second terminal is the second input terminal of the first filter circuit, the second terminal of the third resistor is connected to the first terminal of the second capacitor, the second terminal of the first capacitor and the second terminal of the second capacitor are connected to the reference ground. , the second end of the third resistor is the output end of the first filter circuit.

Further, the resistance of the first resistor is 3.3kΩ; the resistance of the third resistor is 470Ω; the capacitance of the first capacitor and the second capacitor is 220pF.

Further, the voltage bias circuit includes: a 3.3V power supply and a second resistor;

Wherein, the first end of the second resistor is connected to the 3.3V power supply, and the second end of the second resistor is the transmission end of the voltage bias circuit.

Further, the resistance of the second resistor is 3.3kΩ.

Further, the first comparison circuit includes: a first operational amplifier, a fifth resistor, an eighth resistor, and a fourth capacitor;

Wherein, the second input terminal of the first operational amplifier is the first input terminal of the first comparison circuit, the first terminal of the fifth resistor is the second input terminal of the first comparison circuit, and the first terminal of the fifth resistor is connected to the fourth input terminal of the first operational amplifier. The first end of the capacitor is connected, the second end of the fourth capacitor is connected to the reference ground, the second end of the fifth resistor is connected to the first end of the eighth resistor and the first input end of the first operational amplifier respectively, and the first operational amplifier The output terminal of the amplifier is connected to the second terminal of the eighth resistor, and the output terminal of the first operational amplifier is the output terminal of the first comparison circuit.

Further, the resistance of the fifth resistor is 22kΩ; the resistance of the eighth resistor is 1MΩ; the capacitance of the fourth capacitor is 1000pF; the model of the first operational amplifier is LF353M.

Further, the second comparison circuit includes: a second operational amplifier, a third capacitor, a sixth resistor, and a seventh resistor;

Wherein, the first terminal of the sixth resistor is the first input terminal of the second comparison circuit, the second terminal of the sixth resistor is connected to the first terminal of the seventh resistor and the first input terminal of the second operational amplifier respectively. The second input terminal of the operational amplifier is the second input terminal of the second comparison circuit. The second input terminal of the second operational amplifier is connected to the first terminal of the third capacitor. The second terminal of the third capacitor is connected to the reference ground. The output terminal of the second operational amplifier is connected to the second terminal of the seventh resistor, and the output terminal of the second operational amplifier is the output terminal of the second comparison circuit.

Further, the resistance of the sixth resistor is 22kΩ; the resistance of the seventh resistor is 1MΩ; the capacitance of the third capacitor is 220pF; the model of the second operational amplifier is LF353M.

Further, the logic limiting circuit includes: 3.3V power supply and ninth resistor;

The first end of the ninth resistor is connected to the 3.3V power supply, and the second end of the ninth resistor is the transmission end of the logic limiting circuit.

Further, the resistance of the ninth resistor is 1kΩ.

Further, the second filter circuit includes: a fourth resistor and a fifth capacitor;

Wherein, the first end of the fourth resistor is the input end of the second filter circuit, the second end of the fourth resistor is connected to the first end of the fifth capacitor, the second end of the fifth capacitor is connected to the reference ground, and the fourth resistor The second end of is the output end of the second filter circuit.

Further, the resistance of the fourth resistor is 470Ω; the capacitance of the fifth capacitor is 1000pF.

Further, the logic levels include: 0V and 3.3V.

Embodiments of the utility model can solve the problem that the input voltage signal exceeds the voltage range that the electronic device can withstand and affects the normal operation of the electronic device. The embodiment of the present invention uses a first filter circuit, a voltage bias circuit, a first comparison circuit, a second comparison circuit, a logic limiting circuit, and a second filter circuit; wherein, the first input end of the first filter circuit receives the input voltage. signal, the second input terminal of the first filter circuit is connected to the transmission terminal of the voltage bias circuit, and the output terminal of the first filter circuit is respectively connected to the first input terminal of the first comparison circuit and the first input terminal of the second comparison circuit. Connection; the second input end of the first comparison circuit receives the upper amplitude voltage signal; the output end of the first comparison circuit is respectively connected to the output end of the second comparison circuit, the transmission end of the logic limiting circuit, and the input end of the second filter circuit ; The second input terminal of the second comparison circuit receives the lower limiting voltage signal; the output terminal of the second comparison circuit is respectively connected to the transmission terminal of the logic limiting circuit and the input terminal of the second filter circuit; the transmission terminal of the logic limiting circuit is connected to The input terminal of the second filter circuit is connected; the output terminal of the second filter circuit outputs the logic level after limiting and judging; the first filter circuit is used to receive the input voltage signal and perform the positive voltage signal converted by the voltage bias circuit. Filtering; the voltage bias circuit is used to convert the input voltage signal received by the first filter circuit into a positive voltage signal; the first comparison circuit is used to receive the upper amplitude voltage signal and compare the upper amplitude voltage signal with the positive voltage output by the first filter circuit The maximum amplitude of the signal outputs the first level according to the comparison result; the second comparison circuit is used to receive the lower limiting voltage signal, compare the lower limiting voltage signal with the minimum amplitude of the positive voltage signal output by the first filter circuit, and output the first level according to the comparison result. Output the second level; the logic limiting circuit is used to determine the logical relationship between the first level and the second level, and output the logic level; the second filter circuit is used to filter the logic level, and output the filtered logic level. . The embodiment of the utility model realizes the conversion of the input voltage signal into a logic level, determines whether the input voltage signal exceeds the preset voltage limiting range through the logic level, and stops the electronic device when the input voltage signal exceeds the preset voltage limiting range. work and can protect electronic equipment; the embodiment of the utility model filters the input voltage signal and the output logic level, thereby enhancing the anti-interference performance of the device and improving reliability.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description These are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts. In the attached picture:

FIG. 1 is a schematic diagram of a voltage signal limiting determination device provided in an embodiment of the present invention.

FIG. 2 is a circuit diagram of a voltage signal limiting judging device provided in an embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present utility model more clear, the embodiments of the present utility model will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments of the present utility model and their descriptions are used to explain the present utility model, but are not used to limit the present utility model.

The term "and/or" in this article only describes an association relationship, indicating that three relationships can exist. For example, A and/or B can mean: A alone exists, A and B exist simultaneously, and B alone exists. situation. In addition, the term "at least one" herein means any one of a plurality or any combination of at least two of a plurality, for example, including at least one of A, B, and C, which can mean including from A, Any one or more elements selected from the set composed of B and C.

In the description of this specification, the words "includes", "includes", "has", "contains", etc. are all open terms, meaning including but not limited to. Reference to the terms "one embodiment," "a specific embodiment," "some embodiments," "such as," etc. in the description means that a particular feature, structure or characteristic described in connection with the embodiment or example is included in at least one of the present application in an embodiment or example. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. The sequence of steps involved in each embodiment is used to schematically illustrate the implementation of the present application. The sequence of steps is not limited and can be adjusted appropriately as needed.

Figure 1 is a schematic diagram of a voltage signal limiter judgment device provided in an embodiment of the present invention. As shown in Figure 1, the voltage signal limiter judgment device includes: a first filter circuit 1, a voltage bias circuit 2, a first Comparator circuit 3, second comparison circuit 4, logic limiting circuit 5, second filter circuit 6;

Wherein, the first input end of the first filter circuit 1 receives the input voltage signal, the second input end of the first filter circuit 1 is connected to the transmission end of the voltage bias circuit 2, and the output end of the first filter circuit 1 is respectively connected to the first The first input terminal of the comparison circuit 3 is connected to the first input terminal of the second comparison circuit 4; the second input terminal of the first comparison circuit 3 receives the upper amplitude voltage signal; the output terminal of the first comparison circuit 3 is connected to the second input terminal respectively. The output end of the comparison circuit 4, the transmission end of the logic limiting circuit 5, and the input end of the second filter circuit 6 are connected; the second input end of the second comparison circuit 4 receives the lower limiting voltage signal; the output end of the second comparison circuit 4 are respectively connected to the transmission end of the logic limiting circuit 5 and the input end of the second filter circuit 6; the transmission end of the logic limiting circuit 5 is connected to the input end of the second filter circuit 6; the output end of the second filter circuit 6 is Logic level after limiting judgment;

The first filter circuit 1 is used to receive the input voltage signal and filter the positive voltage signal converted by the voltage bias circuit 2; the voltage bias circuit 2 is used to convert the input voltage signal received by the first filter circuit 1 into a positive voltage signal. ; The first comparison circuit 3 is used to receive the upper amplitude voltage signal, compare the upper amplitude voltage signal with the maximum amplitude of the positive voltage signal output by the first filter circuit 1, and output the first level according to the comparison result; the second comparison circuit 4 is used After receiving the lower limiter voltage signal, compare the lower limiter voltage signal with the minimum amplitude of the positive voltage signal output by the first filter circuit, and output the second level according to the comparison result; the logic limiter circuit 5 is used to determine the first level and the second level. The second filter circuit 6 is used to filter the logic level and output the filtered logic level.

FIG. 2 is a circuit diagram of a voltage signal limiting judging device provided in an embodiment of the present invention.

In one embodiment, referring to Figure 2, the first filter circuit 1 includes: a first resistor R1, a third resistor R3, a first capacitor C1, and a second capacitor C2; wherein the first end of the first resistor R1 is the first resistor R1. The first input terminal of the filter circuit 1 and the second terminal of the first resistor R1 are respectively connected to the first terminal of the third resistor R3 and the first terminal of the first capacitor C1. The second terminal of the first resistor R1 is the first filter The second input terminal of the circuit 1 and the second terminal of the third resistor R3 are connected to the first terminal of the second capacitor C2. The second terminals of the first capacitor C1 and the second terminal of the second capacitor C2 are connected to the reference ground. The second end of the three resistors R3 is the output end of the first filter circuit 1; the first end of the first resistor R1 receives the input voltage signal Vin, and after being filtered by the first filter circuit 1, the voltage signal Vin_t is output. The first filter circuit 1 can filter out high-frequency interference voltage signals to make the voltage signals more stable.

In one embodiment, referring to Figure 2, the voltage bias circuit 2 includes: a 3.3V power supply and a second resistor R2; wherein the first end of the second resistor R2 is connected to the 3.3V power supply, and the second end of the second resistor R2 is the transmission end of the voltage bias circuit 2; that is, the second end of the second resistor R2 is connected to the second end of the first resistor R1 and the first end of the third resistor R3 respectively. The voltage bias circuit 2 is used to convert the input sinusoidal voltage signal into a forward input voltage signal.

In one embodiment, referring to Figure 2, the first comparison circuit 3 includes: a first operational amplifier U1A, a fifth resistor R5, an eighth resistor R8, and a fourth capacitor C4; wherein, the second input terminal of the first operational amplifier U1A is the first input terminal of the first comparison circuit 3, the first terminal of the fifth resistor R5 is the second input terminal of the first comparison circuit 3, the first terminal of the fifth resistor R5 is connected to the first terminal of the fourth capacitor C4 , the second end of the fourth capacitor C4 is connected to the reference ground, the second end of the fifth resistor R5 is respectively connected to the first end of the eighth resistor R8 and the first input end of the first operational amplifier U1A, and the first operational amplifier U1A The output terminal is connected to the second terminal of the eighth resistor R8, and the output terminal of the first operational amplifier U1A is the output terminal of the first comparison circuit 3. Specifically, the output signal from the output terminal of the first operational amplifier U1A is fed back through the eighth resistor R8, which reduces the influence of the second operational amplifier U1B on the first operational amplifier U1A and realizes the connection between the first comparison circuit 3 and the second comparison circuit 4. Weak isolation between; the first input terminal of the first operational amplifier U1A is the negative input pin 32, the second input terminal of the first operational amplifier U1A is the positive input pin 33, and the output terminal of the first operational amplifier U1A is the output pin Pin 31; the first input terminal of the first comparison circuit 3 receives the upper amplitude voltage signal V_LimH. The first comparison circuit 3 is used to compare the upper amplitude voltage signal V_LimH with the maximum amplitude of the voltage signal Vin_t output by the first filter circuit, and output the first Level, if the maximum amplitude is less than or equal to the upper amplitude voltage signal V_LimL, the first level is 0V; if the maximum amplitude is greater than the upper amplitude voltage signal V_LimH, the second level is 1V.

In one embodiment, referring to Figure 2, the second comparison circuit 4 includes: a second operational amplifier U1B, a third capacitor C3, a sixth resistor R6, and a seventh resistor R7; wherein, the first end of the sixth resistor R6 is the The first input terminal of the second comparison circuit 4 and the second terminal of the sixth resistor R6 are respectively connected to the first terminal of the seventh resistor R7 and the first input terminal of the second operational amplifier U1B. The second input terminal of the second operational amplifier U1B The terminal is the second input terminal of the second comparison circuit 4, the second input terminal of the second operational amplifier U1B is connected to the first terminal of the third capacitor C3, the second terminal of the third capacitor C3 is connected to the reference ground, and the second operational amplifier U1B is connected to the first terminal of the third capacitor C3. The output terminal of the amplifier U1B is connected to the second terminal of the seventh resistor R7 , and the output terminal of the second operational amplifier U1B is the output terminal of the second comparison circuit 4 . Specifically, the first input terminal of the second operational amplifier U1B is the positive input pin 43, and the second input terminal of the second operational amplifier U1A is the negative input pin 42, which is used to receive the lower limiting voltage signal V_LimL. The first operational amplifier The output terminal of U1A is output pin 41; the second comparison circuit 4 is used to compare the minimum amplitude of the lower limit voltage signal V_LimL with the voltage signal Vin_t output by the first filter circuit, and output the second level. If the minimum amplitude is greater than or If the minimum amplitude is equal to the lower limiting voltage signal V_LimL, the second level is 0V; if the minimum amplitude is less than the lower limiting voltage signal V_LimL, the second level is 1V.

In one embodiment, the first operational amplifier U1A and the second operational amplifier U1B are integrated inside a chip, which reduces errors caused by temperature drift. +15V and -15V are used to pair the first operational amplifier U1A and the second operational amplifier U1B. Power supply is provided to achieve full-scale linear coverage of the input voltage from +10V to -10V, expanding the linear range of the input voltage.

In one embodiment, referring to Figure 2, the logic limiting circuit 5 includes: a 3.3V power supply and a ninth resistor R9; wherein, the first end of the ninth resistor R9 is connected to the 3.3V power supply, and the second end of the ninth resistor R9 is The transmission end of the logic limiting circuit 5. Specifically, the logic limiting circuit 5 determines the logical relationship between the first level and the second level and outputs the logic level; if the first level is 0V and the second level is 0V, the output logic level is low level 0V. ;If the first level is 1V and the second level is 0V, the output logic level is high level 3.3V; if the first level is 0V and the second level is 1V, the output logic level is high level 3.3V; if the first level is 1V and the second level is 1V, the output logic level is high level 3.3V.

In one embodiment, referring to Figure 2, the second filter circuit 6 includes: a fourth resistor R4 and a fifth capacitor C5; wherein the first end of the fourth resistor R4 is the input end of the second filter circuit 6, and the fourth resistor R4 The second end of R4 is connected to the first end of the fifth capacitor C5, the second end of the fifth capacitor C5 is connected to the reference ground, and the second end of the fourth resistor R4 is the output end of the second filter circuit 6. Specifically, the second filter circuit 6 filters the logic level and outputs the filtered logic level Vout. When the logic level is low level 0V, the input voltage signal does not exceed the preset voltage limiting range, and the electronic device can Normal operation; when the logic level is high level 3.3V, the input voltage signal exceeds the preset voltage limit range, and the electronic equipment needs to be stopped to protect the electronic equipment.

In one embodiment, the resistance of the first resistor R1 and the second resistor R2 is 3.3kΩ; the resistance of the third resistor R3 and the fourth resistor R4 is 470Ω; the resistance of the fifth resistor R5 and the sixth resistor R6 is 22kΩ; the resistance of the seventh resistor R7 and the eighth resistor R8 is 1MΩ; the resistance of the ninth resistor is 1kΩ; the capacitance of the first capacitor C1, the second capacitor C2, and the third capacitor C3 is 220pF; the fourth capacitor C4 The capacitance of the fifth capacitor C5 is 1000pF. The resistors and capacitors used in the embodiments of the utility model are common types, which expands the practical scope of the utility model.

In one embodiment, the models of the first operational amplifier U1A and the second operational amplifier U1B are LF353M.

To sum up, the embodiment of the present invention uses a first filter circuit, a voltage bias circuit, a first comparison circuit, a second comparison circuit, a logic limiting circuit, and a second filter circuit; wherein, the first element of the first filter circuit The input terminal receives the input voltage signal, the second input terminal of the first filter circuit is connected to the transmission terminal of the voltage bias circuit, and the output terminal of the first filter circuit is respectively connected to the first input terminal of the first comparison circuit and the second comparison circuit. The first input terminal is connected; the second input terminal of the first comparison circuit receives the upper amplitude voltage signal; the output terminal of the first comparison circuit is respectively connected to the output terminal of the second comparison circuit, the transmission terminal of the logic limiting circuit, and the second filtering circuit. The input end of the circuit is connected; the second input end of the second comparison circuit receives the lower limiting voltage signal; the output end of the second comparison circuit is respectively connected with the transmission end of the logic limiting circuit and the input end of the second filter circuit; the logic limiting circuit The transmission end of the circuit is connected to the input end of the second filter circuit; the output end of the second filter circuit outputs the logic level after limiting and judging; the first filter circuit is used to receive the input voltage signal and convert the voltage bias circuit The positive voltage signal is filtered; the voltage bias circuit is used to convert the input voltage signal received by the first filter circuit into a positive voltage signal; the first comparison circuit is used to receive the upper amplitude voltage signal and compare the upper amplitude voltage signal with the first filtered The maximum amplitude of the positive voltage signal output by the circuit outputs the first level according to the comparison result; the second comparison circuit is used to receive the lower limit voltage signal and compare the lower limit voltage signal with the minimum amplitude of the positive voltage signal output by the first filter circuit value, and outputs the second level according to the comparison result; the logic limiting circuit is used to determine the logical relationship between the first level and the second level, and outputs the logic level; the second filter circuit is used to filter the logic level, and outputs the filtered the subsequent logic level. The embodiment of the utility model uses a small number of components and has a simple structure, which converts the input voltage signal into a logic level, and determines whether the input voltage signal exceeds the preset voltage limiting range through the logic level. When the input voltage signal exceeds the preset voltage limit range, When the voltage limit range is in the range, the electronic equipment can be protected by stopping the operation of the electronic equipment; the embodiment of the utility model performs multi-level low-pass filtering on the input voltage signal and output logic level, which enhances the anti-interference performance of the device and has strong applicability. Improved reliability.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the utility model shall be included in the protection scope of the utility model.

Claims (14)

1. A voltage signal limiting judgment device, characterized in that it includes: a first filter circuit (1), a voltage bias circuit (2), a first comparison circuit (3), a second comparison circuit (4), a logic Limiting circuit (5), second filter circuit (6); Wherein, the first input terminal of the first filter circuit (1) receives the input voltage signal, the second input terminal of the first filter circuit (1) is connected to the transmission terminal of the voltage bias circuit (2), and the first filter circuit (1) ) are respectively connected to the first input terminal of the first comparison circuit (3) and the first input terminal of the second comparison circuit (4); the second input terminal of the first comparison circuit (3) receives the upper amplitude voltage signal; the output terminal of the first comparison circuit (3) is respectively connected to the output terminal of the second comparison circuit (4), the transmission terminal of the logic limiting circuit (5), and the input terminal of the second filter circuit (6); the second The second input terminal of the comparison circuit (4) receives the lower limiting voltage signal; the output terminal of the second comparison circuit (4) is connected to the transmission terminal of the logic limiting circuit (5) and the input terminal of the second filter circuit (6) respectively. ; The transmission end of the logic limiting circuit (5) is connected to the input end of the second filter circuit (6); the output end of the second filter circuit (6) outputs the logic level after the limiter judgment; The first filter circuit (1) is used to receive the input voltage signal and filter the positive voltage signal converted by the voltage bias circuit (2); the voltage bias circuit (2) is used to filter the positive voltage signal received by the first filter circuit (1). The input voltage signal is converted into a positive voltage signal; the first comparison circuit (3) is used to receive the upper amplitude voltage signal, compare the upper amplitude voltage signal with the maximum amplitude of the positive voltage signal output by the first filter circuit (1), and based on the comparison result Output the first level; the second comparison circuit (4) is used to receive the lower limiting voltage signal, compare the lower limiting voltage signal with the minimum amplitude of the positive voltage signal output by the first filter circuit, and output the second level according to the comparison result; The logic limiting circuit (5) is used to determine the logical relationship between the first level and the second level and output the logic level; the second filter circuit (6) is used to filter the logic level and output the filtered logic level. . 2. The voltage signal limiter judgment device according to claim 1, characterized in that the first filter circuit (1) includes: a first resistor, a third resistor, a first capacitor, and a second capacitor; Wherein, the first end of the first resistor is the first input end of the first filter circuit (1), the second end of the first resistor is connected to the first end of the third resistor and the first end of the first capacitor respectively. The second end of a resistor is the second input end of the first filter circuit (1), the second end of the third resistor is connected to the first end of the second capacitor, the second end of the first capacitor and the third end of the second capacitor The two ends are connected to the reference ground, and the second end of the third resistor is the output end of the first filter circuit (1). 3. The voltage signal limiting judging device according to claim 2, wherein the resistance of the first resistor is 3.3kΩ; the resistance of the third resistor is 470Ω; the capacitance of the first capacitor and the second capacitor is 220pF. 4. The voltage signal limiting judgment device according to claim 1, characterized in that the voltage bias circuit (2) includes: a 3.3V power supply and a second resistor; The first end of the second resistor is connected to the 3.3V power supply, and the second end of the second resistor is the transmission end of the voltage bias circuit (2). 5. The voltage signal amplitude limiting judging device according to claim 4, wherein the resistance of the second resistor is 3.3 kΩ. 6. The voltage signal limiting judgment device according to claim 1, characterized in that the first comparison circuit (3) includes: a first operational amplifier, a fifth resistor, an eighth resistor, and a fourth capacitor; Wherein, the second input terminal of the first operational amplifier is the first input terminal of the first comparison circuit (3), the first terminal of the fifth resistor is the second input terminal of the first comparison circuit (3), and the first terminal of the fifth resistor is the second input terminal of the first comparison circuit (3). The first terminal is connected to the first terminal of the fourth capacitor, the second terminal of the fourth capacitor is connected to the reference ground, and the second terminal of the fifth resistor is respectively connected to the first terminal of the eighth resistor and the first input of the first operational amplifier. terminal is connected, the output terminal of the first operational amplifier is connected to the second terminal of the eighth resistor, and the output terminal of the first operational amplifier is the output terminal of the first comparison circuit (3). 7. The voltage signal limiting judging device according to claim 6, wherein the resistance of the fifth resistor is 22kΩ; the resistance of the eighth resistor is 1MΩ; the capacitance of the fourth capacitor is 1000pF; the first operation The amplifier model is LF353M. 8. The voltage signal limiter judgment device according to claim 1, characterized in that the second comparison circuit (4) includes: a second operational amplifier, a third capacitor, a sixth resistor, and a seventh resistor; The first end of the sixth resistor is the first input end of the second comparison circuit (4), and the second end of the sixth resistor is connected to the first end of the seventh resistor and the first input end of the second operational amplifier respectively. , the second input terminal of the second operational amplifier is the second input terminal of the second comparison circuit (4), the second input terminal of the second operational amplifier is connected to the first terminal of the third capacitor, and the second terminal of the third capacitor It is connected to the reference ground, and the output terminal of the second operational amplifier is connected to the second terminal of the seventh resistor. The output terminal of the second operational amplifier is the output terminal of the second comparison circuit (4). 9. The voltage signal limiting judging device according to claim 8, wherein the sixth resistor has a resistance of 22kΩ; the seventh resistor has a resistance of 1MΩ; the third capacitor has a capacitance of 220pF; the second operation The amplifier model is LF353M. 10. The voltage signal limiting judgment device according to claim 1, characterized in that the logic limiting circuit (5) includes: a 3.3V power supply and a ninth resistor; Wherein, the first end of the ninth resistor is connected to the 3.3V power supply, and the second end of the ninth resistor is the transmission end of the logic limiting circuit (5). 11. The voltage signal amplitude limiting judging device according to claim 10, wherein the resistance of the ninth resistor is 1 kΩ. 12. The voltage signal limiting judgment device according to claim 1, characterized in that the second filter circuit (6) includes: a fourth resistor and a fifth capacitor; Wherein, the first end of the fourth resistor is the input end of the second filter circuit (6), the second end of the fourth resistor is connected to the first end of the fifth capacitor, and the second end of the fifth capacitor is connected to the reference ground. The second end of the fourth resistor is the output end of the second filter circuit (6). 13. The voltage signal amplitude limiting judging device according to claim 12, wherein the resistance of the fourth resistor is 470Ω; the capacitance of the fifth capacitor is 1000pF. 14. The voltage signal amplitude limiting judging device according to claim 1, wherein the logic levels include: 0V and 3.3V.