CN119395384A

CN119395384A - Resistance value measuring system and control method

Info

Publication number: CN119395384A
Application number: CN202411545429.9A
Authority: CN
Inventors: 齐园园; 胡文波; 徐俊锋; 王惠; 冯旺; 莫贞田
Original assignee: Jiangxi Luxshare Intelligent Manufacture Co Ltd
Current assignee: Jiangxi Luxshare Intelligent Manufacture Co Ltd
Priority date: 2024-10-31
Filing date: 2024-10-31
Publication date: 2025-02-07

Abstract

The application provides a resistance value measuring system and a control method, wherein the resistance value measuring system comprises a voltage measuring module and an error calibrating module, wherein the voltage measuring module is used for being connected with a resistor to be measured and outputting actual measurement voltage after the voltage measuring module is connected with the resistor to be measured, the error calibrating module is connected with the voltage measuring module and used for determining target voltage corresponding to the resistor to be measured through subtracting the error voltage from the actual measurement voltage and determining the target resistance value of the resistor to be measured based on the target voltage, and the error voltage is voltage which is not added to the resistor to be measured in the actual measurement voltage. The application solves the problem that the resistance of the resistor with small resistance cannot be accurately measured in the related technology.

Description

Resistance value measuring system and control method

Technical Field

The present application relates to the field of circuit design technologies, and in particular, to a resistance measurement system and a control method.

Background

In the related art, a four-wire DMM (digital multimeter ) or an instrument LCR (L: inductance, C: capacitance, R: resistance) is mostly used for measuring resistance values. However, when the small resistance value resistance of 1 to 100mΩ is measured by the measuring instrument, there is a case where the measured value is not accurate enough and there is a deviation between the measured value and the ideal value.

Therefore, the related art has a technical problem that accurate resistance measurement cannot be performed on the resistor with the small resistance.

Disclosure of Invention

The application provides a resistance value measuring system and a control method, which at least solve the problem that the resistance value of a small resistance resistor cannot be accurately measured in the related art.

In a first aspect, the application provides a resistance measuring system, which comprises a voltage measuring module and an error calibrating module;

The voltage measurement module is used for connecting a resistor to be measured and outputting the measured voltage of the voltage measurement module after being connected with the resistor to be measured;

The error calibration module is connected with the voltage measurement module and is used for determining a target voltage corresponding to the resistor to be measured by subtracting the error voltage from the actual measurement voltage and determining a target resistance value of the resistor to be measured based on the target voltage, wherein the error voltage is a voltage which is not added to the resistor to be measured in the actual measurement voltage.

Optionally, the error calibration module comprises an error calibration circuit and a resistance measurement circuit;

The error calibration circuit is connected with the voltage measurement module and is used for adjusting and obtaining a specified output voltage with the same size as the error voltage, wherein the error voltage comprises a circuit voltage of a resistor access circuit and an output end voltage of the voltage measurement module when a differential signal input into the voltage measurement module is 0, and the resistor access circuit is a circuit used for accessing the resistor to be measured in the voltage measurement module;

the resistance measuring circuit is connected with the error calibrating circuit and is used for obtaining the target voltage by making a difference between the actually measured voltage and the appointed output voltage and determining the target resistance value of the resistor to be measured according to the target voltage.

Optionally, the error calibration circuit comprises a linear power supply, a voltage dividing unit and an adder;

The linear power supply is used for outputting a first voltage, wherein the first voltage is the same as the voltage of the output end;

The voltage dividing unit is connected with the linear power supply and is used for outputting a second voltage according to the first voltage and an external direct current power supply;

the adder is connected with the linear power supply and the voltage dividing unit respectively and is used for adding the first voltage and the second voltage to obtain a third voltage.

Optionally, the error calibration circuit further comprises a voltage follower;

the voltage follower is arranged between the linear power supply and the voltage dividing unit and is used for outputting the first voltage to the voltage dividing unit.

Optionally, the voltage dividing unit comprises a fixed resistor and a potentiometer which are connected in series;

The fixed resistor is connected with the voltage follower and is used for acquiring the first voltage output by the voltage follower;

The first end of the potentiometer is connected with a fourth voltage and a grounding end respectively, and the second end of the potentiometer is connected with the fixed resistor and is used for enabling the second end to output the second voltage with the same size as the circuit voltage through adjusting the resistance value of the potentiometer.

Optionally, the resistance measurement circuit comprises a subtractor;

The subtracter is used for determining the difference between the actually measured voltage and the appointed output voltage, and indicating that the resistance value measuring system is calibrated under the condition that the voltage measuring module is not connected with a resistor to be measured and the output end of the subtracter is made to be 0V by adjusting the error calibrating circuit.

Optionally, the control system as described above further comprises a reference voltage circuit;

The voltage input end of the low dropout linear voltage regulator of the reference voltage circuit is used for being connected with an external direct current power supply;

The voltage input end of the low dropout linear voltage regulator is connected with the sleep end through a resistor of 100KΩ;

the grounding end of the low dropout linear voltage regulator is connected with the sleep end through a resistor of 51KΩ;

The output end of the reference voltage circuit is connected with the voltage measuring module and is used for outputting 5V reference voltage to the voltage measuring module.

In a second aspect, the present application provides a method for controlling a resistance measurement system, including:

the output voltage measuring module is connected with the measured voltage of the resistor to be measured;

And subtracting an error voltage from the measured voltage by an error calibration module to determine a target voltage corresponding to the resistor to be measured, and determining a target resistance value of the resistor to be measured based on the target voltage, wherein the error voltage is a voltage which is not added to the resistor to be measured in the measured voltage.

Optionally, in the foregoing control method, before the output voltage measurement module accesses the measured voltage of the resistor to be measured, the method further includes:

The method comprises the steps of obtaining a specified output voltage with the same size as an error voltage through adjustment of an error calibration circuit, wherein the error voltage comprises a circuit voltage of a resistor access circuit and an output end voltage of a voltage measurement module when a differential signal input into the voltage measurement module is 0, and the resistor access circuit is a circuit used for accessing the resistor to be measured in the voltage measurement module;

The method comprises the steps of subtracting error voltage from actual measurement voltage to determine target voltage corresponding to the resistor to be measured, wherein the step of obtaining the target voltage of the resistor to be measured by means of difference between the actual measurement voltage and the specified output voltage through a resistance measuring circuit, and determining the target resistance of the resistor to be measured according to the target voltage.

Optionally, according to the foregoing control method, the adjusting, by the error calibration circuit, the specified output voltage having the same magnitude as the error voltage includes:

And under the condition that the voltage measurement module is not connected with the resistor to be measured, determining to adjust the error calibration circuit until the output end of the resistor measurement circuit is 0V, so as to obtain the specified output voltage with the same size as the error voltage.

Compared with the prior art, the system provided by the embodiment of the application has the advantages that the voltage measuring module and the error calibration module are arranged, the voltage measuring module is used for being connected with a resistor to be measured and outputting the actual measurement voltage of the voltage measuring module after the voltage measuring module is connected with the resistor to be measured, the error calibration module is connected with the voltage measuring module and used for determining the target voltage corresponding to the resistor to be measured through subtracting the error voltage from the actual measurement voltage and determining the target resistance value of the resistor to be measured based on the target voltage, and the error voltage is the voltage which is not added on the resistor to be measured in the actual measurement voltage. Therefore, under the condition that the measured voltage measured by the voltage measurement module comprises voltages of other circuits except the resistor to be measured, the error calibration module can still remove the error voltage from the measured voltage to determine the target voltage corresponding to the resistor to be measured, and even if the target resistance is smaller, the target resistance of the resistor to be measured can still be accurately determined based on the target voltage, so that the problem that accurate resistance measurement cannot be accurately performed on the resistor with the small resistance in the related technology can be effectively solved.

Drawings

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

In order to more clearly illustrate the embodiments of the invention or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, and it will be obvious to a person skilled in the art that other drawings can be obtained from these drawings without inventive effort.

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which the figures of the drawings are not to be taken in a limiting sense, unless otherwise indicated.

FIG. 1 is a block diagram of a resistance measurement system according to an embodiment of the present application;

FIG. 2 is a schematic circuit diagram of a voltage measurement module according to an embodiment of the present application;

fig. 3 is a schematic circuit diagram of a resistor access circuit according to an embodiment of the present application;

FIG. 4 is a schematic circuit diagram of a resistance measurement circuit according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a reference voltage circuit according to an embodiment of the present application;

FIG. 6 is a flowchart illustrating a control method of a resistance measurement system according to an embodiment of the present application.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The following disclosure provides many different embodiments, or examples, for implementing different structures of the invention. In order to simplify the present disclosure, components and arrangements of specific examples are described below. They are, of course, merely examples and are not intended to limit the invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

In order to solve the technical problem that the accurate resistance measurement of the small-resistance resistor cannot be performed accurately in the prior art, the application provides a resistance measurement system, which comprises a voltage measurement module and an error calibration module; the error calibration module is connected with the voltage measurement module and is used for determining a target voltage corresponding to the resistor to be measured by subtracting the error voltage from the actual measured voltage and determining a target resistance value of the resistor to be measured based on the target voltage, wherein the error voltage is a voltage which is not added to the resistor to be measured in the actual measured voltage. Therefore, under the condition that the measured voltage measured by the voltage measurement module comprises voltages of other circuits except the resistor to be measured, the error calibration module can still remove the error voltage from the measured voltage to determine the target voltage corresponding to the resistor to be measured, and even if the target resistance is smaller, the target resistance of the resistor to be measured can still be accurately determined based on the target voltage, so that the problem that accurate resistance measurement cannot be accurately performed on the resistor with the small resistance in the related technology can be effectively solved.

FIG. 1 is a diagram showing a resistance measuring system according to an embodiment of the present application, including a voltage measuring module 11 and an error calibrating module 12;

The voltage measuring module 11 is used for connecting the resistor to be measured and outputting the actual measurement voltage after the voltage measuring module is connected with the resistor to be measured;

the error calibration module 12 is connected to the voltage measurement module, and is configured to determine a target voltage corresponding to the resistor to be measured by subtracting the error voltage from the measured voltage, and determine a target resistance value of the resistor to be measured based on the target voltage, where the error voltage is a voltage that is not applied to the resistor to be measured from the measured voltage.

In this embodiment, the voltage measurement module 11 may be a circuit structure capable of accessing a resistor to be measured and measuring the measured voltage on the resistor to be measured.

In this embodiment, the resistor to be measured may be a small-resistance resistor having a resistance value of less than 100mΩ.

Because the voltage measurement module 11 has a certain resistance value, when the voltage measurement module 11 is used to measure the resistor with a small resistance value, a larger part of the measured voltage measured by the voltage measurement module 11 is applied to the circuit of the voltage measurement module 11, and when the resistance value of the resistor to be measured is smaller, the voltage on the circuit of the voltage measurement module 11 is larger, that is, the smaller the resistor to be measured is, the larger the error voltage is, so that if the resistance value of the resistor to be measured is determined directly based on the measured voltage, the measurement accuracy of the resistor to be measured is low.

Since the method of the embodiment is mainly used for measuring the resistance value of the small resistor, in order to calculate the resistance value of the resistor to be measured more accurately, the voltage measuring module 11 may be a circuit structure or a chip with a gain capable of amplifying the voltage to be more easily processed, and optionally, the gain may be 100, 200, and so on.

In this embodiment, after subtracting the error voltage from the measured voltage, the target voltage applied to the resistor to be measured is determined, and further, the current flowing through the resistor to be measured may be determined again, so as to determine the actual voltage according to the target voltage and the Gain, and finally, the target resistance of the resistor to be measured may be determined according to the current and the actual voltage, where the actual voltage V _{Actual practice is that of}：V_{Actual practice is that of}＝(V_{Actual practice is that of}-V_{Error of})/Gain may be determined by the following formula.

Alternatively, in order to facilitate calculation, the current flowing through the resistor to be measured may be a constant current source I, and the magnitude of the constant current source I may be 80mA, 90mA, or the like, and further, the constant current source I may be fixed at 100mA, so as to facilitate calculation.

Optionally, as shown in fig. 2, a schematic circuit structure diagram of an optional voltage measurement module 11 is provided:

The voltage measurement module 11 (i.e., current SENSE AMP IC U2 shown in fig. 2) employs INA240A3 with Gain of gain=100. Probe1 and Probe2 are used to measure the resistance across, ensuring that the shorting resistance is less than 100mohm. Hook5 and Hook6 are used for externally connecting a constant current source I, and the constant current source I is fixed at 100mA. Hook7 and Hook8 are used to debug the circuitry.

In the system of this embodiment, under the condition that the measured voltage measured by the voltage measurement module 11 includes voltages of circuits other than the resistor to be measured, the error calibration module is still capable of rejecting the error voltage from the measured voltage to determine the target voltage corresponding to the resistor to be measured, so that even if the target resistance is smaller, the target resistance of the resistor to be measured can still be accurately determined based on the target voltage, and further the problem that in the related art, accurate resistance measurement cannot be performed on the resistor with small resistance can be effectively solved.

As an alternative embodiment, the error calibration module 12 includes an error calibration circuit and a resistance measurement circuit, as in the control system described above;

The error calibration circuit is connected with the voltage measurement module 11 and is used for adjusting and obtaining a specified output voltage with the same size as the error voltage, wherein the error voltage comprises a circuit voltage of a resistor access circuit and an output end voltage of the voltage measurement module 11 when a differential signal input into the voltage measurement module 11 is 0, and the resistor access circuit is a circuit in the voltage measurement module 11 and is used for accessing a resistor to be measured;

The resistance measuring circuit is connected with the error calibrating circuit and is used for obtaining a target voltage by making a difference between the actually measured voltage and the appointed output voltage and determining the target resistance value of the resistor to be measured according to the target voltage.

Specifically, in the present embodiment, the error calibration module 12 includes an error calibration circuit and a resistance measurement circuit. The error calibration circuit is used for adjusting and obtaining the appointed output voltage with the same size as the error voltage, then outputting the appointed output voltage to the resistance measurement circuit, and the resistance measurement circuit can obtain the actual measurement voltage, so that the resistance measurement circuit can obtain the target voltage actually applied to the resistor to be measured by making a difference between the actual measurement voltage and the appointed output voltage, and further can determine the target resistance value of the resistor to be measured according to the current flowing through the resistor to be measured and the target voltage.

In the disclosure, the error voltage includes a circuit voltage of a resistor access circuit, which is a circuit in the voltage measurement module 11 for accessing a resistor to be measured, as shown in fig. 3, the resistor access circuit may include a Probe1 and a Probe2 for connecting two ends of the resistor to be measured, and in order to ensure measurement accuracy, it should be ensured that a short circuit resistance value of the Probe1 and the Probe2 is less than 100mΩ. In addition, the error voltage further includes an output voltage of the voltage measuring module 11 when the differential signal of the input voltage measuring module 11 is 0, for example, when the VS terminal of the Current SENSE AMP IC U2 is pressurized to vs_5v0 and the differential signal of the input voltage measuring module 11 is 0 as shown in fig. 3, the output voltage is 2V5. Therefore, the error calibration circuit is a circuit for eliminating the voltage causing the error in the process of finally calculating the target resistance value of the resistor to be measured.

As an alternative embodiment, the error calibration circuit comprises a linear power supply, a voltage dividing unit and an adder, wherein the linear power supply is connected with the voltage dividing unit;

and the linear power supply is used for outputting a first voltage, wherein the first voltage is the same as the voltage of the output end. Specifically, the linear power supply may be a linear power supply selected from ADR441-EP, and is used for outputting the reference voltage source vref_2v5, i.e. the first voltage is 2.5V, and as shown in fig. 3, the V _in of the linear power supply LDO IC U3 is connected to the reference voltage source vs_5v0, and the gnd terminal is grounded.

The voltage dividing unit is connected with the linear power supply and is used for outputting a second voltage according to the first voltage and the external direct current power supply. Specifically, the voltage division unit is connected with the linear power supply and is used for obtaining the first voltage, and in addition, the voltage division unit is also connected with an external direct current power supply, so that the voltage division unit can generate the second voltage VCOMP_DIV according to the first voltage and the external direct current power supply and output the second voltage VCOMP_DIV.

As shown in fig. 3, an alternative circuit configuration diagram of the error calibration circuit is provided in this embodiment. The adder is connected with the linear power supply and the voltage dividing unit respectively and is used for adding the first voltage and the second voltage to obtain a third voltage. Specifically, an adder (i.e., SUM AMP IC U5 shown in fig. 3) of the type INA105 may be employed and connected to the linear power supply and the voltage dividing unit, respectively, so that the adder may obtain the first voltage vref_2v5 and the second voltage vcomp_div and then add the first voltage vref_2v5 and the second voltage vcomp_div to obtain the third voltage VCAL. As shown in fig. 2, the 1_ref terminal of the adder is used for inputting the first voltage vref_2v5, the 3_in+ terminal is used for inputting the second voltage vcomp_div, the 7_V + terminal is used for externally connecting the dc power source vs_15v0, and the output vcal=vcomp_div+vref_2v5.

As an alternative embodiment, the error calibration circuit further comprises a voltage follower as in the control system described above;

The voltage follower is arranged between the linear power supply and the voltage dividing unit and is used for outputting a first voltage to the voltage dividing unit. Specifically, in order to avoid the interaction between vref_2v5 and vcomp_div, a voltage follower is further added in this embodiment, and the voltage follower (i.e., voltage Follower IC U shown in fig. 3) employs INA105 and is disposed between the linear power supply (i.e., LDO IC U3) and the voltage dividing unit to isolate vref_2v5 from vcomp_div. And, the voltage follower is externally connected with a direct current power supply VS-15V0 through the HOOK9, and the port 7_V of the voltage follower is externally connected with the direct current power supply VS-15V 0.

As an alternative embodiment, the voltage dividing unit comprises a fixed resistor and a potentiometer which are connected in series;

the fixed resistor is connected with the voltage follower and used for acquiring a first voltage output by the voltage follower;

The first end of the potentiometer is connected with a fourth voltage and a grounding end respectively, and the second end of the potentiometer is connected with a fixed resistor for enabling the second end to output a second voltage with the same size as the circuit voltage through adjusting the resistance value of the potentiometer.

Specifically, as shown in fig. 3, the fixed resistance R4 may employ a resistance of 10kΩ whose error is in the range of 1%. The potentiometer may employ a variable resistor having a maximum resistance of 10kΩ with an error in the range of 1%. And the fixed resistor may be connected to the output terminal of the voltage follower, so that the first voltage output by the voltage follower may be obtained. The first end of the potentiometer is respectively connected with a fourth voltage and a grounding end, and the fourth voltage can be obtained by connecting the HOOK10 with a direct current power supply VS-15V 0. The second end of the potentiometer is connected with a fixed resistor, so that the purpose of adjusting the voltage VCOMP_DIV output by the second end can be achieved by adjusting the resistance value of the potentiometer, and whether the second voltage is the same as the circuit voltage or not can be judged by comparing the second voltage with the circuit voltage.

Through the arrangement of the voltage dividing unit, the purpose of generating the second voltage with the same size as the circuit voltage can be achieved, and therefore a basis is provided for accurately determining the target voltage of the resistor to be measured in the later period.

As an alternative embodiment, a resistance measurement circuit, as in the control system described above, includes a subtractor;

The subtracter is used for determining the difference between the measured voltage and the specified output voltage, and indicating that the resistance value measuring system is calibrated under the condition that the voltage measuring module 11 is not connected with the resistor to be measured and the output end of the subtracter is made to be 0V by adjusting the error calibrating circuit.

Specifically, the subtractor (i.e., DIFFERENCE AMP IC U6 shown in fig. 4) may be a subtractor of type INA105, and may be used to subtract the above-mentioned measured voltage v_res_amp_out from the specified output voltage VCAL, so as to obtain the target voltage VEND after removing the error voltage, as shown in the following formula:

VEND=V_RES_AMP_OUT–VCAL。

Further, the 6_OUT end and the 1_REF end of the subtracter are respectively connected with a Hook11 and a Hook12 for measuring the target voltage.

The specific principle of error calibration is as follows:

shorting Probe1 and Probe2, i.e. the voltage measurement module 11 is not connected with the resistor to be measured, at this time, the resistor measured in the voltage measurement module 11 only includes the resistor corresponding to the resistor access circuit of the voltage measurement module 11;

Since v_res_amp_out= (i× (rreal+ Rerror)) ×gain+2v5, where rreal=0Ω, rreal is the resistance of the resistor to be tested, rerror is the resistance of the resistor access circuit, I is the Current value of the constant Current source, 2V5 is the output voltage of the voltage measurement module 11 when the differential signal of the input voltage measurement module 11 is 0 and the VS terminal of the Current SENSE AMP IC U2 is pressurized to vs_5v0;

Further, when the short circuits Probe1 and Probe2 are obtained, v_res_amp_out= (i× Rerror) ×gain+2v5;

The potentiometer RP1 is adjusted so that (i× Rerror) ×gain=vcomp_div;

Since vcal=vcomp\u DIV + VREF _2v5, and VREF_2V 5=2v5;

therefore, when v_res_amp_out=vcal, i.e. v_res_amp_out-vcal=vend=0v, i.e. the error calibration circuit makes the output terminal of the subtractor 0V, calibration of the resistance measurement system is completed.

Calibration standard DMM (digital multimeter Digital Multimeter) measured to 0V between Hook11 and Hook12, the calibration was successful.

As an alternative embodiment, the control system as described above further comprises a reference voltage circuit;

the voltage input end of the low dropout linear voltage regulator of the reference voltage circuit is used for connecting an external direct current power supply;

The grounding end of the low-dropout linear voltage regulator is connected with the sleep end through a 51KΩ resistor;

The output end of the reference voltage circuit is connected with the voltage measuring module 11 and is used for outputting 5V reference voltage to the voltage measuring module 11.

Taking a reference voltage circuit as an example for generating a 5V0 reference voltage circuit, as shown in fig. 5, the reference voltage circuit is described as follows, a low dropout linear regulator (i.e., LDO IC U1 shown in fig. 5) in the reference voltage circuit adopts a regulator model REF195, the REF195 regulator is used for outputting a reference voltage source vs_5v0, and an output terminal of the reference voltage circuit is connected to the voltage measurement module 11, so that the voltage measurement module 11 (i.e., INA240A3 IC shown in fig. 2) is supplied with a 5V0 reference voltage. The voltage input terminal (i.e., the VS terminal shown in fig. 5) of REF195 is connected to the sleep terminal through a resistor having an error of 100kΩ within 1%, and the ground terminal (i.e., the GND terminal shown in fig. 5) of REF195 is connected to the sleep terminal through a resistor having an error of 51kΩ within 1%. Further, hook1 (connected to the VS terminal) and Hook2 (connected to the GND terminal) are used to connect to the dc power supply 15V0.Hook3 (connected to the OUT terminal) and Hook4 (connected to the GND terminal) are used for debugging the circuit.

An embodiment of performing resistance calculation using the resistance measurement system according to any of the foregoing embodiments is provided as follows:

VEND=V_RES_AMP_OUT-VCAL

=[(I×(Rreal+Rerror))×Gain+2V5]-[VCOMP_DIV+VREF_2V5];

since in step one, the potentiometer RP1 has been adjusted so that (i× Rerror) ×gain=vcomp_div;

Thus, vend= (i×rreal) ×gain; i.e., rreal=vend/(i×gain);

since I=100 mA and gain=100, rreal=VEND/10;

with i=100 ma, gain=100, an example is calculated by rreal=vend/10:

If vend=1v, rreal=100mΩ, if vend=0.1V, rreal=10mΩ, if vend=0.01V, rreal=1mΩ, and DMM can accurately measure 0.01V voltage, so that the system of the embodiment can accurately measure the resistance value of 1mΩ.

As shown in fig. 6, according to another aspect of the present disclosure, there is also provided a control method of a resistance measurement system, including the steps of:

step S202, outputting the actual measurement voltage of the resistor to be measured after the voltage measurement module is connected with the resistor to be measured;

Step S204, determining a target voltage corresponding to the resistor to be tested by subtracting the error voltage from the actual measurement voltage through the error calibration module, and determining a target resistance value of the resistor to be tested based on the target voltage, wherein the error voltage is a voltage which is not added to the resistor to be tested in the actual measurement voltage.

The specific implementation manner of the control method of the resistance measurement system in this embodiment may refer to the description of the related embodiments of the resistance measurement system, and will not be repeated here.

As an alternative embodiment, in the foregoing control method, before the output voltage measurement module accesses the measured voltage of the resistor to be measured, the method further includes:

The method comprises the steps of obtaining a specified output voltage with the same size as an error voltage through adjustment of an error calibration circuit, wherein the error voltage comprises a circuit voltage of a resistor access circuit and an output end voltage of a voltage measurement module when a differential signal of an input voltage measurement module is 0, and the resistor access circuit is a circuit used for accessing a resistor to be measured in the voltage measurement module;

Determining a target voltage corresponding to the resistor to be measured from the actually measured voltage comprises the steps of obtaining the target voltage of the resistor to be measured by differentiating the actually measured voltage and the appointed output voltage through a resistance measuring circuit, and determining the target resistance value of the resistor to be measured according to the target voltage.

As an alternative embodiment, the adjusting, by the error calibration circuit, the specified output voltage having the same magnitude as the error voltage according to the control method includes:

And under the condition that the voltage measurement module is not connected with the resistor to be measured, determining to adjust the error calibration circuit until the output end of the resistor measurement circuit is 0V, and obtaining the designated output voltage with the same size as the error voltage.

Compared with the prior art, the system provided by the embodiment of the application has the advantages that the voltage measuring module and the error calibrating module are arranged, the voltage measuring module is used for being connected with the resistor to be measured and outputting the actual measurement voltage of the voltage measuring module after the voltage measuring module is connected with the resistor to be measured, the error calibrating module is connected with the voltage measuring module and used for determining the target voltage corresponding to the resistor to be measured in the actual measurement voltage and determining the target resistance value of the resistor to be measured based on the target voltage. Therefore, under the condition that the measured voltage measured by the voltage measurement module comprises voltages of other circuits except the resistor to be measured, the error calibration module can still determine the target voltage corresponding to the resistor to be measured in the measured voltage, and further, the target resistance of the resistor to be measured can be accurately determined based on the target voltage, and further, the problem that accurate resistance measurement cannot be accurately performed on the resistor with the small resistance in the related technology can be effectively solved.

The apparatus embodiments described above are merely illustrative, wherein the elements illustrated as separate elements may or may not be physically separate, and the elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

From the above description of embodiments, it will be apparent to those skilled in the art that the embodiments may be implemented by means of software plus a general purpose hardware platform, or may be implemented by hardware. Based on such understanding, the foregoing technical solution may be embodied essentially or in a part contributing to the related art in the form of a software product, which may be stored in a computer readable storage medium, such as ROM/RAM, a magnetic disk, an optical disk, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform the method described in the respective embodiments or some parts of the embodiments.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only, and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "includes," "including," and "having" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order described or illustrated, unless an order of performance is explicitly stated. It should also be appreciated that additional or alternative steps may be used.

The foregoing is only a specific embodiment of the invention to enable those skilled in the art to understand or practice the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The resistance value measuring system is characterized by comprising a voltage measuring module and an error calibrating module;

2. The system of claim 1, wherein the error calibration module comprises an error calibration circuit and a resistance measurement circuit;

3. The system of claim 2, wherein the error calibration circuit comprises a linear power supply, a voltage divider unit, and an adder;

4. The system of claim 3, wherein the error calibration circuit further comprises a voltage follower;

5. The system of claim 4, wherein the voltage dividing unit comprises a fixed resistor and a potentiometer connected in series;

6. The system of claim 2, wherein the resistance measurement circuit comprises a subtractor;

7. The system of claim 1, further comprising a reference voltage circuit;

The grounding end of the low dropout linear voltage regulator is connected with the sleep end through a 51KΩ resistor;

8. A control method of a resistance measurement system is characterized by comprising the following steps:

9. The control method of claim 8, wherein prior to the output voltage measurement module accessing the measured voltage of the resistor under test, the method further comprises:

10. The control method according to claim 9, wherein the adjusting by the error calibration circuit to obtain the specified output voltage having the same magnitude as the error voltage includes: