Graded regulation and control type voltage signal detection circuit

Abstract

The utility model discloses a grading regulation and control type voltage signal detection circuit, and belongs to the technical field of voltage signal detection. The circuit comprises a multi-stage voltage division module, a voltage division adjusting module and a signal detection end, and the multi-stage voltage division module is coupled to a detected load and used for achieving multi-gear voltage division of the voltage difference between the positive electrode and the negative electrode; the voltage division adjusting module controls access of divider resistors of different gears through a switching unit, and dynamic adjustment adapting to different voltage ranges is achieved. And the signal detection end is used for detecting and outputting the processed voltage signal. The circuit can automatically switch proper voltage division coefficients according to different load voltages, realizes wide-range high-precision voltage detection, effectively improves the stability and accuracy of voltage acquisition, improves the test quality and production efficiency of a PIV curve, and is especially suitable for test application of voltage fluctuation sensitive equipment such as a laser.

Description

Technical Field

[0001] The present application relates to the technical field of voltage signal detection, and in particular to a step-controlled wide-range voltage signal detection circuit. Background Art

[0002] Existing test systems typically need to collect voltage signals between the positive and negative electrodes of a load device under test. Common solutions typically include a voltage divider circuit, a follower circuit, and a subtractor composed of an operational amplifier. For example, the positive and negative voltages of the load device under test are each reduced to a voltage range suitable for subsequent circuit processing via a voltage divider resistor network. The signal is then stabilized by a follower and fed into a subtractor, which converts the voltage difference between the two terminals into a single-ended signal. Finally, after further voltage division, it is fed into the ADC port of a microcontroller for analog-to-digital conversion. This type of circuit can detect load voltages in the range of 5V to 60V.

[0003] However, when the load voltage under test is lower than 5V, the voltage acquisition accuracy decreases due to the large voltage division ratio, resulting in significant signal fluctuations and abnormal acquisition curves. Furthermore, the existing solution's fixed voltage division ratio cannot be flexibly adjusted for different voltage ranges, limiting its applicability for wide-range voltage detection. Utility Model Content

[0004] The present application provides a step-by-step control voltage signal detection circuit to solve the problems of low acquisition accuracy, large fluctuation and unadjustable voltage division ratio in the existing voltage signal detection circuit in a low voltage range.

[0005] In a first aspect, the present application provides a step-by-step control voltage signal detection circuit, the circuit comprising:

[0006] A multi-stage voltage divider module is coupled to the positive and negative electrodes of the load under test and is used to divide the voltage difference between the positive and negative electrodes of the load under test, including a voltage divider signal output terminal, a positive voltage divider terminal, and a negative voltage divider terminal;

[0007] MCU control chip, the MCU control chip includes a signal detection terminal and a control signal output terminal;

[0008] The signal detection end is coupled to the voltage division signal output end of the multi-stage voltage division module, and is used to detect the voltage signal output by the voltage division signal output end;

[0009] A voltage-dividing regulating module, comprising a switching unit and a plurality of independent branches, each of which is connected in series with at least one voltage-dividing resistor;

[0010] The control signal output terminal is coupled to the switching unit;

[0011] The switching unit is used to determine a corresponding independent branch from a plurality of independent branches in response to a control signal output by the MCU control chip, and couple the corresponding independent branch to the positive voltage dividing terminal and the negative voltage dividing terminal.

[0012] Optionally, the multi-stage voltage divider module includes a first voltage divider submodule, a subtractor follower submodule and a second voltage divider submodule;

[0013] The first voltage dividing submodule includes a positive voltage dividing input terminal, a negative voltage dividing input terminal, a positive voltage dividing output terminal and a negative voltage dividing output terminal;

[0014] The subtractor follower submodule includes a first input terminal, a second input terminal and an output terminal;

[0015] The positive voltage divider input terminal of the first voltage divider submodule is coupled to the positive electrode of the load under test, the negative voltage divider input terminal is coupled to the negative electrode of the load under test, the positive voltage divider output terminal is coupled to the first input terminal of the subtractor follower module, and the negative voltage divider output terminal is coupled to the second input terminal of the subtractor follower submodule;

[0016] The output terminal of the subtractor follower submodule is coupled to the input terminal of the second voltage divider submodule;

[0017] The output terminal of the second voltage dividing submodule is coupled to the signal detection terminal.

[0018] Optionally, the first voltage dividing submodule includes a positive voltage dividing unit and a negative voltage dividing unit;

[0019] The input end of the positive voltage divider unit is coupled to the positive electrode of the load under test, and the output end is coupled to the first input end of the subtractor follower submodule;

[0020] The input end of the negative voltage divider unit is coupled to the negative electrode of the load under test, and the output end is coupled to the second input end of the subtractor follower submodule.

[0021] Optionally, the positive voltage dividing unit includes a first resistor, a first crystal diode, a first follower, a first filter capacitor, and a second filter capacitor;

[0022] The input end of the first resistor is coupled to the positive electrode of the load to be measured, and the output end is coupled to the input end of the first crystal diode and the input end of the first follower respectively;

[0023] The output terminal of the first follower is coupled to the first input terminal of the subtractor follower submodule;

[0024] Input terminals of the first filter capacitor and the second filter capacitor are respectively coupled to the first follower, and output terminals thereof are grounded.

[0025] Optionally, the negative voltage dividing unit includes a second resistor, a second crystal diode, and a second follower;

[0026] The input end of the second resistor is coupled to the negative electrode of the load under test, and the output end is coupled to the input end of the second crystal diode and the input end of the second follower respectively;

[0027] The output terminal of the second follower is coupled to the second input terminal of the subtractor follower submodule.

[0028] Optionally, the subtractor follower submodule includes a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a third follower, a third filter capacitor, and a fourth filter capacitor;

[0029] The third follower includes a positive input terminal, a negative input terminal and an output terminal;

[0030] The input end of the fifth resistor is coupled to the positive voltage-dividing output end of the first voltage-dividing submodule, and the output end is coupled to the positive input end of the third follower;

[0031] The input end of the sixth resistor is coupled to the negative voltage-dividing output end of the first voltage-dividing submodule, and the output end is coupled to the negative input end of the third follower;

[0032] The input end of the seventh resistor is coupled to the positive input end of the third follower, and the output end is grounded;

[0033] The input end of the eighth resistor is coupled to the negative input end of the third follower, and the output end of the eighth resistor is coupled to the output end of the third follower;

[0034] The input end of the third filter capacitor is coupled to the third follower, and the output end is grounded;

[0035] An input terminal of the fourth filter capacitor is coupled to the third follower, and an output terminal of the fourth filter capacitor is grounded.

[0036] Optionally, the second voltage dividing submodule includes an output voltage dividing unit and a voltage follower module;

[0037] The input end of the output voltage divider unit is coupled to the output end of the subtractor follower submodule, and the output end is coupled to the input end of the voltage follower module;

[0038] The output terminal of the voltage follower module is coupled to the signal detection terminal.

[0039] Optionally, the output voltage dividing unit includes a ninth resistor and a tenth resistor;

[0040] The input end of the ninth resistor is coupled to the output end of the subtractor follower submodule, and the output end is coupled to the input end of the tenth resistor;

[0041] An output terminal of the tenth resistor is grounded.

[0042] Optionally, the voltage follower module includes a third crystal diode and a fourth follower;

[0043] The input end of the fourth follower is coupled to the output end of the voltage follower module, and the output end is coupled to the signal detection end;

[0044] The third crystal diode is coupled to the fourth follower.

[0045] Optionally, the switching unit includes a plurality of resistor connection terminals, a signal input terminal, a VDD pin, an INH pin, a VEE pin, a GND pin and a fifth filter capacitor;

[0046] Each of the resistor connection ends is coupled to each independent branch;

[0047] The signal input terminal is coupled to the control signal output terminal of the MCU control chip;

[0048] The input end of the fifth filter capacitor is coupled to the VDD pin, and the output end is grounded;

[0049] The INH pin, VEE pin, and GND pin are grounded respectively.

[0050] The utility model provides a voltage divider adjustment module that can be switched in different levels in the voltage signal detection circuit, and combines a multi-level voltage divider, follower, and subtraction processing structure to enable the circuit to automatically or on demand switch to a suitable independent branch according to the measured voltage range, and couple the voltage divider resistor on the independent branch to the positive voltage divider terminal and the negative voltage divider terminal, thereby achieving stable and high-precision voltage acquisition within a wide range of 0V to 60V. This solution effectively improves the problem of low signal amplitude and susceptibility to noise interference caused by excessive voltage divider ratio when measuring low voltage (especially below 5V), improves the stability and consistency of voltage acquisition, significantly optimizes the accuracy and smoothness of test curves such as PIV, reduces the need for repeated testing due to unstable measurements, and improves the overall efficiency and production consistency of the test system. It has the advantages of simple structure, wide application range, and easy integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The accompanying drawings are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present invention, and together with the description, serve to explain the principles of the present invention.

[0052] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0053] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0054] Figure 1 A schematic diagram of the module structure of a step-by-step regulation voltage signal detection circuit provided in an embodiment of the present application;

[0055] Figure 2 This is a schematic diagram of a specific implementation circuit of a step-by-step regulation voltage signal detection circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0056] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0057] The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. To simplify the disclosure of the present invention, the components and configurations of specific examples are described below. Of course, these are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or letters in different examples. This repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or configurations discussed.

[0058] Combine Figure 1 and Figure 2The following are the names of the electronic components in the circuit of the present invention: the first resistor (R1), the first crystal diode (D1), the first follower (U1A), the first filter capacitor (C1), the second filter capacitor (C2), the second resistor (R2), the second crystal diode (D2), the second follower (U1B), the fifth resistor (R5), the sixth resistor (R6), the seventh resistor (R7), the eighth resistor (R8), the third follower (U2A), the third filter capacitor (C3), the fourth filter capacitor (C4), the ninth resistor (R9), the tenth resistor (R10), the switching unit (U3), the voltage divider resistors (R11-R24), the positive electrode of the load under test (LDV+), and the negative electrode of the load under test (LDV-).

[0059] Figure 1 The schematic diagram of the module structure of a step-by-step voltage signal detection circuit provided in an embodiment of the present application includes a multi-stage voltage division module, a signal detection terminal, and a voltage division adjustment module.

[0060] The multi-stage voltage divider module is coupled to the positive and negative electrodes of the load under test and is used to divide the voltage difference between the positive and negative electrodes of the load under test. The multi-stage voltage divider module has a positive voltage divider terminal, a negative voltage divider terminal, and a voltage divider signal output terminal, wherein the positive voltage divider terminal and the negative voltage divider terminal are respectively electrically connected to the positive and negative electrodes of the load under test, and the voltage divider signal output terminal is electrically connected to the signal detection terminal.

[0061] The voltage divider regulation module includes a switching unit and multiple independent branches, each of which is connected in series with at least one voltage divider resistor. The switching unit has a signal input terminal and is capable of determining two of the multiple independent branches based on an input control signal and coupling the corresponding voltage divider resistors of the two branches to the positive voltage divider terminal and the negative voltage divider terminal, respectively.

[0062] In this embodiment, the switching unit can utilize a four-channel, dual-output multiplexed analog switch device, whose outputs are connected to the inputs of multiple independent branches, with the other end of the voltage divider resistor in each independent branch connected to ground. By controlling the conduction path of the switching unit, voltage divider resistors with different resistance combinations can be selected for connection to the circuit, thereby adjusting the voltage division ratio.

[0063] When the circuit is working, the positive and negative voltages of the load under test are respectively divided by the voltage-dividing resistor branches selected in the voltage-dividing adjustment module, and the obtained voltage-dividing signals are output to the signal detection end through the voltage-dividing signal output end of the multi-stage voltage-dividing module, thereby realizing the acquisition and subsequent processing of the measured voltage signal.

[0064] For example, Figure 2 As shown, Figure 2A specific implementation circuit diagram of a step-by-step control voltage signal detection circuit provided in an embodiment of the present application. In the utility model, the essence of the switching unit U3 is a four-channel dual-output multiplexed analog switch, and U3 includes a voltage divider resistor connection end (X0-Y3 pins), a signal input end (A and B pins), a signal output end (X and Y pins), a VDD pin, an INH pin, a VEE pin, and a GND pin. Among them, the voltage divider resistors of multiple independent branches of the voltage divider resistor connection end are connected, and each independent branch is connected in series with at least one voltage divider resistor, as shown in the figure, for the independent branch connected to the X0 pin, the voltage divider resistors include R11 and R12, and the voltage divider resistors on the independent branch connected to the X1 pin include R13 and R14, and so on. Each independent straight line includes at least one voltage divider resistor, and R11-R24 voltage divider resistors are connected to the switching unit U3, and the resistance values ​​of the voltage divider resistors are different. The two signal input terminals A and B pins are connected to the control signal output terminal of the MCU control chip. The MCU control chip outputs a control signal to the signal input terminal of the switching unit through the control signal output terminal, so that the switching unit responds to the control signal, determines the corresponding independent branch from the multiple independent branches connected to the X0-Y3 pins, and couples the voltage divider resistor on the corresponding independent branch to the positive voltage divider terminal and the negative voltage divider terminal.

[0065] Furthermore, the switching unit includes a plurality of resistor connection terminals, a signal input terminal, a VDD pin, an INH pin, a VEE pin, a GND pin, and a fifth filter capacitor. Each of the resistor connection terminals is electrically connected to the input terminals of a plurality of independent branches, each independent branch is connected in series with at least one voltage divider resistor, and the other end of the branch is connected to the positive voltage divider terminal or the negative voltage divider terminal to form different voltage divider paths.

[0066] The signal input end is electrically connected to the control signal output end of the MCU control chip, and is used to receive the control signal output by the MCU to control the on-off state of the switching unit, thereby selectively coupling the corresponding independent branch to the positive voltage divider end and the negative voltage divider end.

[0067] The VDD pin is used to receive the working power supply voltage, the input end of the fifth filter capacitor is electrically connected to the VDD pin, and the output end is grounded, which is used to filter the input power supply; the INH pin, VEE pin and GND pin are grounded respectively to provide a stable reference potential and necessary functional configuration.

[0068] During operation, the MCU outputs a corresponding control signal to the signal input end of the switching unit according to the measured voltage range. The switching unit closes or opens the corresponding resistor connection end according to the state of the control signal, so that the voltage divider resistor of the selected branch is connected to the circuit, thereby adjusting the voltage divider coefficient to achieve adaptive detection of voltages of different ranges.

[0069] In the embodiment of the present invention, the load under test refers to the component under test or the load under test, such as Figure 2 As shown in the figure, the positive pole (LDV+) and negative pole (LDV-) of the load under test are shown in the figure. LDV+ and LDV- generally appear in voltage detection circuits or differential measurement interfaces. LDV is usually represented as Load Voltage, LDV+ is the positive measurement point of the load voltage, and LDV- is the negative measurement point of the load voltage.

[0070] In actual application scenarios, the load under test usually has different voltages and can be divided into multiple gears, for example, 0-60V gear, 0-30V gear, 0-15V gear, and 0-5V gear. When detecting the load device under test, it is usually necessary to collect the voltage signal between the positive voltage divider terminal and the negative voltage divider terminal after a multi-stage voltage divider module, and input different currents to draw the corresponding PIV curve. When the voltage of the load under test is lower than 5V, due to the large voltage divider ratio, the voltage acquisition accuracy decreases, and the signal fluctuates greatly, resulting in abnormal acquisition result curves. Therefore, it is necessary for the MCU control chip to send corresponding control signals for the load under test with different voltage gears, so that the switching unit analog switch responds to the corresponding control signal, determines the corresponding independent branch among multiple independent branches, and couples the corresponding independent voltage divider resistors to the positive voltage divider terminal and the negative voltage divider terminal.

[0071] like Figure 1 As shown, the multi-stage voltage divider module includes a first voltage divider submodule, a subtractor follower submodule, and a second voltage divider submodule. The positive voltage divider unit has an input electrically connected to the positive electrode of the load under test, and an output electrically connected to the first input of the subtractor follower submodule. This divides the positive voltage signal and then feeds it into the subtractor follower submodule.

[0072] The input end of the negative voltage divider unit is electrically connected to the negative pole of the load under test, and the output end is electrically connected to the second input end of the subtractor follower submodule, and is used to divide the negative voltage signal and then send it to the subtractor follower submodule.

[0073] During operation, the positive and negative signals of the measured load are independently divided by the positive voltage divider unit and the negative voltage divider unit respectively, and are sent to the subtractor follower submodule respectively to achieve isolation and amplitude stabilization of the positive and negative signals, ensuring signal stability and accuracy during differential processing.

[0074] like Figure 2As shown, since the maximum positive voltage loaded on the voltage divider regulation module, the first voltage divider submodule and the subtractor follower submodule is +12V, when a 0-60V measured load is connected, the voltage of the measured load greater than 12V must be divided to 12V. It should be noted that the utility model divides the measured load into four gears, and the maximum threshold and minimum threshold of the specific divided gears can be flexibly adjusted according to actual conditions and actual needs. The utility model is not limited to the threshold range of each gear.

[0075] Taking a 0-60V measured load as an example, the maximum voltage that can pass through the voltage divider adjustment module, the first voltage divider submodule and the subtractor follower submodule is 12V, and the maximum voltage that can pass through the second voltage divider submodule is 3.3V. The utility model uses the maximum voltage value of the measured load as the control reference and performs voltage division control according to proportional distribution. For example, the voltage of the measured load of 60V is divided and controlled to 12V. Then, for the measured load voltage of 55V, the proportional voltage division is controlled to 11V, and the measured load of 50V is controlled to 10V according to proportional voltage division, and so on.

[0076] Taking a 0-30V load as an example, the 30V load voltage is divided and adjusted to 12V. Then, for a 25V load voltage, the voltage is divided and adjusted to 10V in proportion. For a 20V load voltage, the voltage is divided and adjusted to 8V in proportion, and so on.

[0077] Taking a 0-15V load as an example, the 30V load voltage is divided and adjusted to 12V. Then, for a 25V load voltage, the voltage is proportionally divided and adjusted to 10V. For a 20V load voltage, the voltage is proportionally divided and adjusted to 8V, and so on.

[0078] After the positive and negative voltage divider terminals of the load under test are divided and regulated to 12V, they must finally pass through the second voltage divider submodule. Therefore, the ninth and tenth resistors in the second voltage divider submodule divide the 12V voltage again to 3.3V. The output terminal of the second voltage divider submodule is coupled to the signal detection terminal of the MCU control chip, and the output voltage signal of the voltage divider signal output terminal is transmitted to the signal detection terminal (ADC interface) of the MCU control chip for real-time voltage detection.

[0079] As for the 0-5V measured load, since the function of this application is to reduce the voltage through the voltage-dividing resistor, the maximum threshold of the measured load in this gear is already less than 12V, so there is no need for further detailed voltage division through the voltage-dividing adjustment module. It is directly divided by the first voltage-dividing submodule and the subtractor follower submodule, and the ninth resistor and the tenth resistor in the second voltage-dividing submodule divide the 0-5V positive voltage-dividing end and the negative voltage-dividing end, and transmit the output voltage signal to the signal test ADC interface of the MCU control chip for real-time voltage detection.

[0080] Furthermore, the positive voltage dividing unit includes a first resistor R1, a first crystal diode D1, a first follower U1A, a first filter capacitor C1 and a second filter capacitor C2.

[0081] The input end of the first resistor R1 is electrically connected to the positive electrode of the load under test, and the output end is electrically connected to the input end of the first crystal diode D1 and the first follower U1A respectively. The first crystal diode D1 is electrically connected to the first follower U1A to provide unidirectional conduction protection during the transmission of positive signals.

[0082] The output terminal of the first follower U1A is electrically connected to the first input terminal of the subtractor follower submodule, and is used to buffer the positive voltage division signal to improve the signal driving capability and stability.

[0083] The input terminals of the first filter capacitor C1 and the second filter capacitor C2 are electrically connected to the output terminal of the first follower U1A respectively, and the output terminals are both grounded, for filtering the buffered positive voltage division signal to suppress high-frequency noise interference.

[0084] During operation, the positive voltage of the measured load is divided by the first resistor R1 and sent to the first follower U1A under the protection of the first crystal diode D1. After being buffered, it is filtered by the filter capacitors C1 and C2 and finally output to the first input terminal of the subtractor follower submodule.

[0085] Furthermore, the negative voltage dividing unit includes a second resistor R2, a second crystal diode D2 and a second follower U1B.

[0086] The input end of the second resistor R2 is electrically connected to the negative electrode of the load under test, and the output end is electrically connected to the second crystal diode D2 and the input end of the second follower U1B respectively. The second crystal diode D2 is electrically connected to the second follower U1B to provide unidirectional conduction protection during the transmission of negative signals.

[0087] The output end of the second follower U1B is electrically connected to the second input end of the subtractor follower submodule, and is used to buffer the negative voltage divided signal to improve the signal driving capability and maintain signal stability.

[0088] During operation, the negative voltage of the load under test is divided by the second resistor R2 and sent to the second follower U1B under the protection of the second crystal diode D2. After buffering, it is output to the second input terminal of the subtractor follower submodule and enters the subsequent differential processing circuit together with the positive voltage division signal.

[0089] Furthermore, the subtractor follower submodule includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a third follower U2A, a third filter capacitor and a fourth filter capacitor.

[0090] The third follower U2A includes a positive input terminal, a negative input terminal, and an output terminal. The input terminal of the fifth resistor R5 is electrically connected to the positive voltage-dividing output terminal of the first voltage-dividing submodule, and the output terminal is electrically connected to the positive input terminal of the third follower U2A. The input terminal of the sixth resistor R6 is electrically connected to the negative voltage-dividing output terminal of the first voltage-dividing submodule, and the output terminal is electrically connected to the negative input terminal of the third follower U2A.

[0091] The input end of the seventh resistor R7 is electrically connected to the positive input end of the third follower U2A, and the output end is grounded; the input end of the eighth resistor R8 is electrically connected to the negative input end of the third follower U2A, and the output end is electrically connected to the output end of the third follower U2A.

[0092] The input terminals of the third filter capacitor and the fourth filter capacitor are electrically connected to the third follower U2A respectively, and the output terminals are grounded, and are used to filter the signal after the differential operation to reduce high-frequency interference.

[0093] During operation, the signals from the positive voltage divider unit and the negative voltage divider unit are respectively input into the third follower U2A through the fifth resistor R5 and the sixth resistor R6, and form a differential operation circuit with the seventh resistor R7 and the eighth resistor R8 to realize the voltage difference calculation of the positive and negative signals; the signal after differential processing is buffered in the third follower U2A, and filtered through the third filter capacitor and the fourth filter capacitor, and finally output to the second voltage divider sub-module.

[0094] Furthermore, the second voltage dividing submodule includes an output voltage dividing unit and a voltage follower module.

[0095] The input end of the output voltage divider unit is electrically connected to the output end of the subtractor follower submodule, and the output end is electrically connected to the input end of the voltage follower module, and is used to divide the voltage signal after differential processing again to match the input range of the subsequent signal processing circuit.

[0096] The output end of the voltage follower module is electrically connected to the signal detection end of the MCU control chip, and is used to buffer the voltage signal after voltage division to prevent the signal from being attenuated or distorted due to the load effect during transmission to the MCU signal detection end.

[0097] During operation, the single-ended voltage signal from the subtractor follower submodule first enters the output voltage divider unit for voltage division processing, then is buffered by the voltage follower module, and finally is stably output to the signal detection end of the MCU control chip for subsequent analog-to-digital conversion and data acquisition.

[0098] Furthermore, the output voltage dividing unit includes a ninth resistor R9 and a tenth resistor R10.

[0099] The input end of the ninth resistor R9 is electrically connected to the output end of the subtractor follower submodule, and the output end is electrically connected to the input end of the tenth resistor R10; the output end of the tenth resistor R10 is grounded, and the two constitute a voltage divider circuit for reducing the voltage signal output by the subtractor follower submodule to a level that adapts to the input range of the subsequent voltage follower module.

[0100] During operation, the voltage signal after differential and buffering processing is first input into the ninth resistor R9, and the voltage amplitude is reduced through series voltage division with the tenth resistor R10, and then output to the voltage follower module for buffering processing to ensure that the voltage signal sent to the MCU signal detection end is stable and within a safe range.

[0101] Furthermore, the voltage follower module includes a third crystal diode D3 and a fourth follower U2B.

[0102] The input end of the fourth follower U2B is electrically connected to the output end of the voltage follower module, and the output end is electrically connected to the signal detection end of the MCU control chip; the third crystal diode D3 is electrically connected to the fourth follower U2B, and is used to provide unidirectional conduction protection before the signal is input to the fourth follower U2B to prevent external reverse voltage from damaging the circuit.

[0103] During operation, the voltage signal from the output voltage divider unit is first input into the fourth follower U2B via the third crystal diode D3. The fourth follower buffers the signal and outputs it to the signal detection terminal of the MCU control chip, realizing stable voltage signal transmission and acquisition.

[0104] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0105] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0106] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in this application can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0107] In the embodiments provided in this application, it should be understood that the disclosed circuits can be implemented in other ways. For example, the circuits described above are merely schematic. For example, the division of the modules or units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0108] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0109] The above embodiments are intended only to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they may still modify the technical solutions described in the above embodiments or replace some of the technical features therein with equivalents; and such modifications or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present application and should be included within the scope of protection of the present application.

Claims

1. A step-by-step control voltage signal detection circuit, characterized in that: The circuit comprises: A multi-stage voltage divider module is coupled to the positive and negative electrodes of the load under test and is used to divide the voltage difference between the positive and negative electrodes of the load under test, including a voltage divider signal output terminal, a positive voltage divider terminal, and a negative voltage divider terminal; MCU control chip, the MCU control chip includes a signal detection terminal and a control signal output terminal; The signal detection end is coupled to the voltage division signal output end of the multi-stage voltage division module, and is used to detect the voltage signal output by the voltage division signal output end; A voltage-dividing regulating module, comprising a switching unit and a plurality of independent branches, each of which is connected in series with at least one voltage-dividing resistor; The control signal output terminal is coupled to the switching unit; The switching unit is used to determine a corresponding independent branch from a plurality of independent branches in response to a control signal output by the MCU control chip, and couple the corresponding independent branch to the positive voltage dividing terminal and the negative voltage dividing terminal.

2. The step-by-step control voltage signal detection circuit according to claim 1, characterized in that: The multi-stage voltage divider module includes a first voltage divider submodule, a subtractor follower submodule and a second voltage divider submodule; The first voltage dividing submodule includes a positive voltage dividing input terminal, a negative voltage dividing input terminal, a positive voltage dividing output terminal and a negative voltage dividing output terminal; The subtractor follower submodule includes a first input terminal, a second input terminal and an output terminal; The positive voltage divider input terminal of the first voltage divider submodule is coupled to the positive electrode of the load under test, the negative voltage divider input terminal is coupled to the negative electrode of the load under test, the positive voltage divider output terminal is coupled to the first input terminal of the subtractor follower module, and the negative voltage divider output terminal is coupled to the second input terminal of the subtractor follower submodule; The output terminal of the subtractor follower submodule is coupled to the input terminal of the second voltage divider submodule; The output terminal of the second voltage dividing submodule is coupled to the signal detection terminal.

3. The step-by-step control voltage signal detection circuit according to claim 2, characterized in that: The first voltage dividing submodule includes a positive voltage dividing unit and a negative voltage dividing unit; The input end of the positive voltage divider unit is coupled to the positive electrode of the load under test, and the output end is coupled to the first input end of the subtractor follower submodule; The input end of the negative voltage divider unit is coupled to the negative electrode of the load under test, and the output end is coupled to the second input end of the subtractor follower submodule.

4. The step-by-step control voltage signal detection circuit according to claim 3, characterized in that: The positive voltage dividing unit includes a first resistor, a first crystal diode, a first follower, a first filter capacitor, and a second filter capacitor; The input end of the first resistor is coupled to the positive electrode of the load to be measured, and the output end is coupled to the input end of the first crystal diode and the input end of the first follower respectively; The output terminal of the first follower is coupled to the first input terminal of the subtractor follower submodule; Input terminals of the first filter capacitor and the second filter capacitor are respectively coupled to the first follower, and output terminals thereof are grounded.

5. The step-by-step control voltage signal detection circuit according to claim 3, characterized in that: The negative voltage dividing unit includes a second resistor, a second crystal diode, and a second follower; The input end of the second resistor is coupled to the negative electrode of the load under test, and the output end is coupled to the input end of the second crystal diode and the input end of the second follower respectively; The output terminal of the second follower is coupled to the second input terminal of the subtractor follower submodule.

6. The step-by-step control voltage signal detection circuit according to claim 2, characterized in that: The subtractor follower submodule includes a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a third follower, a third filter capacitor, and a fourth filter capacitor; The third follower includes a positive input terminal, a negative input terminal and an output terminal; The input end of the fifth resistor is coupled to the positive voltage-dividing output end of the first voltage-dividing submodule, and the output end is coupled to the positive input end of the third follower; The input end of the sixth resistor is coupled to the negative voltage-dividing output end of the first voltage-dividing submodule, and the output end is coupled to the negative input end of the third follower; The input end of the seventh resistor is coupled to the positive input end of the third follower, and the output end is grounded; The input end of the eighth resistor is coupled to the negative input end of the third follower, and the output end of the eighth resistor is coupled to the output end of the third follower; The input end of the third filter capacitor is coupled to the third follower, and the output end is grounded; An input terminal of the fourth filter capacitor is coupled to the third follower, and an output terminal of the fourth filter capacitor is grounded.

7. The step-by-step control voltage signal detection circuit according to claim 2, characterized in that: The second voltage dividing submodule includes an output voltage dividing unit and a voltage follower module; The input end of the output voltage divider unit is coupled to the output end of the subtractor follower submodule, and the output end is coupled to the input end of the voltage follower module; The output terminal of the voltage follower module is coupled to the signal detection terminal.

8. The step-by-step control voltage signal detection circuit according to claim 7, characterized in that: The output voltage dividing unit includes a ninth resistor and a tenth resistor; The input end of the ninth resistor is coupled to the output end of the subtractor follower submodule, and the output end is coupled to the input end of the tenth resistor; An output terminal of the tenth resistor is grounded.

9. The step-by-step control voltage signal detection circuit according to claim 7, characterized in that: The voltage follower module includes a third crystal diode and a fourth follower; The input end of the fourth follower is coupled to the output end of the voltage follower module, and the output end is coupled to the signal detection end; The third crystal diode is coupled to the fourth follower.

10. The step-by-step control voltage signal detection circuit according to claim 1, characterized in that: The switching unit includes a plurality of resistor connection terminals, a signal input terminal, a VDD pin, an INH pin, a VEE pin, a GND pin and a fifth filter capacitor; Each of the resistor connection ends is coupled to each independent branch; The signal input terminal is coupled to the control signal output terminal of the MCU control chip; The input end of the fifth filter capacitor is coupled to the VDD pin, and the output end is grounded; The INH pin, VEE pin, and GND pin are grounded respectively.

Images