Wide-range current measuring device and measuring method

Abstract

The invention provides a wide-range current measuring device and method, and the device comprises a main control module, a voltage control module, a dynamic adjustment resistance module, and a voltage and current monitoring module, and the main control module determines a current gear according to the monitored initial current of a measured power supply; the voltage control module is controlled to output corresponding control voltage to the dynamic adjustment resistance module according to the current gear, so that the resistance value of the dynamic adjustment resistance module is suitable for the current of the tested power supply; and the current of the measured power supply is measured. When the gear of the current of the measured power supply changes, the control voltage is given according to the current current gear to control the dynamic adjustment resistance module to adjust the sampling resistor, the current current of the measured power supply is adapted, the sampling resistor does not need to be replaced, and various sampling resistors with different measuring ranges do not need to be prepared. Only the resistance value of the dynamic adjustment resistance module is adjusted, so that the area and the cost of the circuit are reduced, and the current measurement precision is ensured.

Description

Technical Field

[0001] The present invention relates to the field of power supply current measurement, and more particularly to a wide-range current measurement device and a measurement method. Background Art

[0002] Current-generation boards require high-precision testing of their power consumption, with current measurement accuracy being particularly crucial. Graphics cards based on NPUs and GPUs experience significant variations in power supply current under different operating conditions, ranging from hundreds of milliamperes to tens of amperes at varying computing power levels. Traditional measurement methods are unable to meet these high-precision requirements. Furthermore, boards have numerous power supplies and require a large number of current measurements. To quickly and accurately obtain current values, current measurement accuracy and test efficiency must be improved. Therefore, a simple, cost-effective, and wide-range multi-current measurement solution is crucial.

[0003] The traditional test solution currently uses current sensors of different ranges or sampling resistors of different resistance values, selected by a gating switch. However, the gating switch in this method also has a certain resistance value, which can lead to inaccurate sampling resistor values, thereby reducing current measurement accuracy.

[0004] Furthermore, in traditional testing solutions, multiple current sensors or sampling resistors with different ranges are used for each current path to be measured. As the number of current paths to be measured increases, the number of corresponding current sensors or sampling resistors increases exponentially, increasing the overall circuit area and cost. Summary of the Invention

[0005] Aiming at the situation where the current values ​​of each power supply vary greatly under different working conditions of the graphics card, resulting in the sampling resistor being unsuitable for the range, the present invention provides a wide-range current measurement device and measurement method.

[0006] According to a first aspect of the present invention, there is provided a wide-range current measuring device, comprising:

[0007] It includes a main control module, a voltage control module, a dynamic adjustment resistance module and a voltage and current monitoring module. The main control module is bidirectionally connected to the voltage and current monitoring module. The output end of the main control module is connected to the input end of the voltage control module. The output end of the voltage control module is connected to the input end of the dynamic adjustment resistance module. The output end of the dynamic adjustment resistance module is connected to the input end of the voltage and current monitoring module.

[0008] The main control module is used to control the voltage and current monitoring module to collect the initial current of the power supply under test, and determine the gear position of the dynamic adjustment resistance module according to the detected initial current of the power supply under test; and control the voltage control module to output the corresponding control voltage according to the gear position of the dynamic adjustment resistance module. to the dynamically adjustable resistance module so that the resistance value of the dynamically adjustable resistance module is suitable for the current of the power supply under test;

[0009] The voltage signal at both ends of the dynamic adjustment resistance module is collected based on the voltage and current monitoring module ;

[0010] According to the control voltage of the dynamic adjustment resistance module , the voltage signal at both ends of the dynamic adjustment resistance module The sampled resistance value of the dynamic adjustment resistance module is used to calculate the current of the power supply under test.

[0011] According to a second aspect of the present invention, a wide-range current measurement method is provided, comprising:

[0012] Step 1: After the power supply under test is powered on, the main control module controls the voltage and current monitoring module to collect the initial current of the power supply under test;

[0013] Step 2: The main control module determines the gear position of the dynamic adjustment resistance module according to the detected initial current of the measured power supply, and controls the voltage control module to output a corresponding control voltage to the dynamic adjustment resistance module according to the gear position of the dynamic adjustment resistance module;

[0014] Step 3, controlling the resistance value of the dynamic adjustment resistance module to be suitable for the current of the power supply under test based on the control voltage;

[0015] Step 4: Collect the voltage signal at both ends of the dynamic adjustment resistance module based on the voltage and current monitoring module ;

[0016] Step 5: dynamically adjust the resistance module to control the voltage , the voltage signal at both ends of the dynamic adjustment resistance module The sampled resistance value of the dynamic adjustment resistance module is used to calculate the current of the power supply under test.

[0017] The present invention provides a wide-range current measurement device and measurement method. The main control module determines the current setting gear according to the initial current of the measured power supply; and according to the current setting gear, controls the voltage control module to output a corresponding control voltage to the dynamic adjustment resistor module, so that the resistance value of the dynamic adjustment resistor module is suitable for the current of the measured power supply; and measures the current of the measured power supply. When the current of the measured power supply changes gear, it is only necessary to provide a control voltage according to the current gear to control the dynamic adjustment resistor module to adjust the sampling resistance value to adapt to the current current of the measured power supply. There is no need to replace the sampling resistor or prepare a plurality of sampling resistors of different ranges. Only the resistance value of the dynamic adjustment resistor module needs to be adjusted. Compared with the existing current sensor and sampling resistor of different ranges, a selection switch with a certain resistance value is introduced to switch the current sensor and sampling resistor of different ranges. The area and cost of the circuit are reduced, and the accuracy of the sampling resistor is guaranteed, thereby ensuring the accuracy of the current measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A structural block diagram of a wide-range current measurement device provided by one embodiment of the present invention;

[0019] Figure 2 A circuit schematic diagram of a voltage control module according to an embodiment of the present invention;

[0020] Figure 3 A circuit schematic diagram of a dynamic resistance adjustment module according to an embodiment of the present invention;

[0021] Figure 4 This is a structural block diagram of a voltage and current monitoring module measuring multiple power supplies under test according to an embodiment of the present invention;

[0022] Figure 5 A structural block diagram of a main control module and a voltage and current monitoring module provided by one embodiment of the present invention;

[0023] Figure 6 This is a workflow diagram of a main control module according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. In addition, the technical features in the various embodiments or single embodiments provided by the present invention can be arbitrarily combined with each other to form a feasible technical solution. This combination is not restricted by the sequence of steps and / or structural composition mode, but must be based on the ability of ordinary technicians in this field to implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0025] The main purpose of the present invention is to provide a current measurement circuit suitable for a wide range, aiming to solve the problem that the current values ​​of each power supply vary greatly under different working conditions of the graphics card, resulting in the sampling resistor being unsuitable for the range. When measuring large currents, in order to reduce the power consumption of the resistor and avoid heat affecting the accuracy or damaging the resistor, it is necessary to select a low-resistance sampling resistor; when measuring small currents, in order to obtain sufficient voltage drop to improve the signal-to-noise ratio and avoid the signal being too small to be submerged by noise, it is necessary to select a higher-resistance sampling resistor. The resistance adjustment of the dynamic resistor is achieved by changing the resistance value of the MOS tube. This method makes the sampling resistor value more accurate and unaffected by the resistance of the gate switch itself. Furthermore, the present invention can measure multiple currents in real time, and the measurement circuit structure is simple and inexpensive. Specifically, the patent provides a method that can adapt to the current of multiple power supplies under test with a wide range by dynamically adjusting the sampling resistor instead of manually soldering and replacing the sampling resistor, significantly reducing test time.

[0026] Figure 1 An embodiment of the present invention provides a wide-range current measuring device, such as Figure 1 As shown, the measuring device includes a main control module, a voltage control module, a dynamic adjustment resistance module and a voltage and current monitoring module. The main control module is bidirectionally connected to the voltage and current monitoring module, the output end of the main control module is connected to the input end of the voltage control module, the output end of the voltage control module is connected to the input end of the dynamic adjustment resistance module, and the output end of the dynamic adjustment resistance module is connected to the input end of the voltage and current monitoring module.

[0027] Among them, the main control module is used to control the voltage and current monitoring module to collect the initial current size of the measured power supply, and determine the setting gear of the dynamic adjustment resistance module according to the detected initial current size of the measured power supply; and control the voltage control module to output the corresponding control voltage according to the setting gear of the dynamic adjustment resistance module. to the dynamically adjustable resistance module so that the resistance value of the dynamically adjustable resistance module is suitable for the current of the power supply under test;

[0028] The voltage signal at both ends of the dynamic adjustment resistance module is collected based on the voltage and current monitoring module ;

[0029] According to the control voltage of the dynamic adjustment resistance module , the voltage signal at both ends of the dynamic adjustment resistance module The sampled resistance value of the dynamic adjustment resistance module is used to calculate the current of the power supply under test.

[0030] It is understandable that when the power supply under test is powered on, the main control module controls the voltage and current monitoring module to collect the initial current of the power supply under test, and determines the current setting gear of the power supply under test based on the collected initial current. According to the current setting gear, the voltage control module outputs the corresponding control voltage. To dynamically adjust the resistance module to control the voltage To adjust the resistance value of the dynamic adjustment resistance module so that the resistance value adapts to the current size of the power supply under test.

[0031] After the resistance value of the dynamic adjustment resistor module is adjusted, the voltage and current monitoring module collects the voltage signals at both ends of the dynamic adjustment resistor module. , according to the control voltage , Dynamically adjust the voltage signal across the resistor module And dynamically adjust the sampling resistance value of the resistance module to calculate the current size of the power supply under test.

[0032] In this embodiment of the present invention, when the current of the power supply under test changes, the current range is determined based on the monitored current of the power supply under test. A control voltage is then applied to control the dynamic adjustment resistor module to adjust the sampling resistor and measure the current current of the power supply under test. When the current range of the power supply under test changes, the sampling resistor does not need to be replaced; only the resistance value of the dynamic adjustment resistor module needs to be adjusted.

[0033] See also Figure 2In one embodiment of the present invention, the voltage control module includes a DAC digital-to-analog converter, a resistor R1, a resistor R2, a resistor R3, a DC-DC converter, an inductor L1, a transient suppression diode D1, and a capacitor C1. The DC-DC converter includes an error comparator A1, a controller, and a MOS tube Q1.

[0034] The input end of the DAC digital-to-analog converter is connected to the output end of the main control module, the output end of the DAC digital-to-analog converter is connected to the negative input end of the error comparator A1 through the resistor R1, and the positive input end of the error comparator A1 is connected to V REF The output of the error comparator A1 is connected to the input of the controller, the output of the controller is connected to the gate G of the MOS transistor Q1, the source of the MOS transistor Q1 is grounded, and the drain of the MOS transistor Q1 outputs a control voltage through the transient suppression diode D1. As for the dynamic adjustment resistance module, the end of the transient suppression diode D1 close to the MOS transistor Q1 is connected to the power supply through the inductor L1, and the end of the transient suppression diode D1 away from the MOS transistor Q1 is grounded through the capacitor C1.

[0035] The main control module is used to determine the gear position of the dynamic adjustment resistance module according to the initial current of the power supply under test, and output the digital control signal of the DAC digital-to-analog converter according to the determined gear position. , digital control signal As the negative input of error comparator A1, the reference voltage As the positive input terminal of the error comparator A1, the output terminal of the error comparator A1 outputs the control voltage through the voltage control module To the dynamic adjustment resistor module.

[0036] Among them, according to Figure 2 The circuit diagram of the voltage control module, its working principle is:

[0037] According to Kirchhoff's law:

[0038] ;

[0039] ;

[0040] ;

[0041] ;

[0042] According to the above formula, the output control voltage of the voltage control module is derived With digital control signal The relationship is:

[0043] ;

[0044] in, is the preset reference voltage signal, 、 and Indicates resistance value.

[0045] See also Figure 3 The dynamic adjustment resistance module includes a MOS transistor Q2 and a resistor R4, which adopts the form of a sampling resistor with a certain resistance value connected in parallel with the MOS transistor. Among them, the resistor R4 is configured as a coarse adjustment sampling resistor, that is, the sampling resistance value is roughly configured according to the estimated current range; the MOS transistor Q2 is configured as a fine adjustment sampling resistor, that is, the sampling resistance is fine-tuned according to the measured current value based on the roughly configured sampling resistor R4. The gate of the MOS transistor Q2 is connected to the control voltage of the output terminal of the voltage control module. The source of the MOS tube Q2 is grounded and serves as the output pin of V1. The drain of the MOS tube Q2 is connected to the output current of the power supply under test and serves as the output pin of V1. 1_H Output pin, the resistor R4 is connected between the source and drain of the MOS tube Q2.

[0046] According to the control voltage output by the voltage control module Control the gate of the MOS transistor Q2 to adjust the on-state resistance of the source and drain of the MOS transistor Q2 , and then adjust the resistance value of the dynamic adjustment resistance module to be suitable for the current size of the power supply under test.

[0047] It is understandable that the control voltage output by the voltage control module Acting on the gate of MOS tube Q2, when the MOS tube is in the linear region, the drain current and It is approximately a linear relationship, with the following expression:

[0048] ;

[0049] When the MOS tube Q2 is in the deep linear region, that is, When the leakage current MOS tube Q2 can be regarded as The resistance of a voltage-controlled linear resistor connected to the source and drain ends is expressed as follows:

[0050] ;

[0051] in, is the voltage change between the drain and source of MOS tube Q2, is the drain current of MOS tube Q2, is the electron migration rate, is the gate oxide capacitance per unit area, is the width-to-length ratio of the oxide layer, is the voltage between the gate and source of the MOS tube, is the threshold voltage of the MOS tube, is the source / drain on-state resistance.

[0052] Connecting a sampling resistor R4 of a suitable resistance value in parallel at both ends of the MOS tube Q2 can realize dynamic adjustment of the resistance value. That is, the main control module determines the sampling resistor position according to the sampled current value, and the voltage control module outputs the appropriate control voltage. , thereby controlling the MOS tube Q2 to reach the appropriate sampling resistance gear, and the sampling module collects V 1_H and the voltage signal across V1 , the measured current value is calculated according to the following formula :

[0053] ;

[0054] Among them, the voltage and current monitoring module is mainly used to collect and process the signals on the sampling resistor. In the embodiment of the present invention, LT2991 is used as the voltage and current monitoring chip, and STM32f103 is used as the main control chip. The main control chip communicates with the voltage and current monitoring chip LT2991 through the I2C protocol.

[0055] The wide-range current measuring device provided by the present invention can measure multiple power supplies at the same time. Figure 4 The current measuring device for multiple power supplies includes a main control module, multiple power supply currents to be measured, multiple voltage control modules, multiple dynamic adjustment resistor modules and a voltage and current monitoring module. The main control module is bidirectionally connected to the voltage and current monitoring module. The output end of the main control module is connected to the input end of each voltage control module, the output end of each voltage control module is connected to the input end of each corresponding dynamic adjustment resistor module, and the output end of each dynamic adjustment resistor module is connected to the input end of the voltage and current monitoring module.

[0056] The main control module is used to control the voltage and current monitoring module to simultaneously collect the initial current size of each power supply under test, and determine the current setting gear corresponding to each power supply under test based on the detected initial current size of each power supply under test; and according to the current setting gear corresponding to each path, control the corresponding voltage control module to output the corresponding control voltage to the corresponding dynamic adjustment resistance module, so that the resistance value of the dynamic adjustment resistance module is suitable for the current size of the corresponding power supply under test.

[0057] The voltage and current monitoring module can simultaneously collect the initial currents of multiple power supplies and dynamically adjust the resistance of the dynamic adjustment resistor module for each power supply under test to adapt to the current of each power supply under test. The adjustment of the sampling resistor value of each power supply under test is independent of each other. The specific method for dynamically adjusting the sampling resistor of each power supply under test can be referred to the aforementioned embodiment and will not be repeated here.

[0058] See also Figure 5 An LT2991 voltage and current monitoring module can simultaneously monitor up to four current signals. The LT2991 uses differential mode to acquire current signals and communicates with the main control module via the I2C protocol. The main control module adjusts the control signal based on the initial current value to determine the appropriate sampling resistor value. The LT2991 then continues to acquire current signals, sends them to the main control module for processing, and outputs the final sampled current value.

[0059] See also Figure 6 The present invention also provides a method for measuring wide-range current based on a wide-range current measuring device, which can be found in Figure 6 , the measurement method mainly includes the following steps:

[0060] Step 1: After the power supply under test is powered on, the main control module controls the voltage and current monitoring module to collect the initial current of the power supply under test;

[0061] Step 2: The main control module determines the current setting gear of the power supply under test according to the detected initial current of the power supply under test, and controls the voltage control module to output a corresponding control voltage to the dynamic adjustment resistance module according to the current setting gear;

[0062] Step 3, controlling the resistance value of the dynamic adjustment resistance module to be suitable for the current of the power supply under test based on the control voltage;

[0063] Step 4: Collect the voltage signal at both ends of the dynamic adjustment resistance module based on the voltage and current monitoring module ;

[0064] Step 5: dynamically adjust the resistance module to control the voltage , the voltage signal at both ends of the dynamic adjustment resistance module The sampled resistance value of the dynamic adjustment resistance module is used to calculate the current of the power supply under test.

[0065] Step 6: Repeat steps 1 to 4 to monitor the current level of the power supply under test in real time and dynamically adjust the resistance value of the dynamic adjustment resistor module to be suitable for the current level of the power supply under test.

[0066] It is understandable that the specific implementation of each step of the wide-range current measurement method provided by the embodiment of the present invention can refer to the aforementioned technical features and will not be described in detail here.

[0067] The present invention provides a wide-range current measurement device and a measurement method, which have the following beneficial effects:

[0068] (1) The designed wide-range current detection device can detect the range of the current of the measured power supply, automatically switch the dynamic adjustment resistance module gear, and obtain the sampling resistance value adapted to the measured current. It does not introduce a selection device with a certain resistance value, thereby improving the detection accuracy, reducing the power consumption of the resistor, and solving the problem of manually welding and replacing the sampling resistor, making the test automated and improving the test efficiency.

[0069] (2) It is suitable for wide-range and multi-channel current measurement and can be expanded accordingly according to the number of power supplies being measured, which is relatively flexible.

[0070] (3) Unlike the measurement scheme that requires a sampling resistor with multiple gears to be selected through a gating device, the wide-range, multi-current detection circuit only requires one set of sampling resistors for each current being measured, which has the advantages of simple structure, small circuit area and low cost.

[0071] It should be noted that, in the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0072] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0073] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A wide-range current measuring device, characterized in that: It includes a main control module, a voltage control module, a dynamic adjustment resistance module and a voltage and current monitoring module. The main control module is bidirectionally connected to the voltage and current monitoring module. The output end of the main control module is connected to the input end of the voltage control module. The output end of the voltage control module is connected to the input end of the dynamic adjustment resistance module. The output end of the dynamic adjustment resistance module is connected to the input end of the voltage and current monitoring module. The main control module is used to control the voltage and current monitoring module to collect the initial current of the power supply under test, and determine the gear position of the dynamic adjustment resistance module according to the detected initial current of the power supply under test; and control the voltage control module to output the corresponding control voltage according to the gear position of the dynamic adjustment resistance module. to the dynamically adjustable resistance module so that the resistance value of the dynamically adjustable resistance module is suitable for the current of the power supply under test; The voltage signal at both ends of the dynamic adjustment resistance module is collected based on the voltage and current monitoring module ; According to the control voltage of the dynamic adjustment resistance module , the voltage signal at both ends of the dynamic adjustment resistance module The sampled resistance value of the dynamic adjustment resistance module is used to calculate the current of the power supply under test.

2. The wide-range current measuring device according to claim 1, characterized in that: The voltage control module includes a DAC digital-to-analog converter, a resistor R1, a resistor R2, a resistor R3, a DC-DC converter, an inductor L1, a transient suppression diode D1, and a capacitor C1. The DC-DC converter includes an error comparator A1, a controller, and a MOS tube Q1. The input end of the DAC digital-to-analog converter is connected to the output end of the main control module, the output end of the DAC digital-to-analog converter is connected to the negative input end of the error comparator A1 through the resistor R1, and the positive input end of the error comparator A1 is connected to V REF The output of the error comparator A1 is connected to the input of the controller, the output of the controller is connected to the gate G of the MOS transistor Q1, the source of the MOS transistor Q1 is grounded, and the drain of the MOS transistor Q1 outputs a control voltage through the transient suppression diode D1. To the dynamic adjustment resistance module, the end of the transient suppression diode D1 close to the MOS transistor Q1 is connected to the power supply through the inductor L1, and the end of the transient suppression diode D1 away from the MOS transistor Q1 is grounded through the capacitor C1; The main control module is used to determine the gear position of the dynamic adjustment resistance module according to the initial current of the power supply under test, and output a digital control signal according to the determined gear position. To the DAC digital-to-analog converter, and output the control voltage through the voltage control module To the dynamic adjustment resistance module.

3. The wide-range current measuring device according to claim 2, characterized in that: The voltage control module outputs a control voltage With the digital control signal The relationship is: ； in, is the preset reference voltage signal, 、 and Indicates resistance value.

4. The wide-range current measuring device according to claim 1, characterized in that: The dynamic adjustment resistance module includes a MOS transistor Q2 and a resistor R4, wherein the MOS transistor Q2 is configured as a fine adjustment sampling resistor, and the resistor R4 is configured as a coarse adjustment sampling resistor. The gate of the MOS transistor Q2 is connected to the output end of the voltage control module, the source of the MOS transistor Q2 is grounded and serves as the V1 output pin, and the drain of the MOS transistor Q2 is connected to the output current of the power supply under test and serves as the V 1_H Output pin, the resistor R4 is connected between the source and drain of the MOS tube Q2; According to the control voltage output by the voltage control module Control the gate of the MOS transistor Q2 to adjust the on-state resistance of the source and drain of the MOS transistor Q2 , and then adjust the resistance value of the dynamic adjustment resistance module to be suitable for the current size of the power supply under test.

5. The wide-range current measuring device according to claim 4, characterized in that: When the MOS transistor Q2 is in the deep linear region, the MOS transistor Q2 is considered to be A voltage-controlled linear resistor connected to the source and drain ends, whose resistance is for: ； in, is the voltage change between the drain and source of MOS tube Q2, is the drain current of MOS tube Q2, is the electron migration rate, is the gate oxide capacitance per unit area, is the aspect ratio of the oxide layer, is the voltage between the gate and source of MOS tube Q2, that is, the control voltage, is the threshold voltage of MOS tube Q2, It is the source and drain on-state resistance of MOS tube Q2.

6. The wide-range current measuring device according to claim 4, characterized in that: According to the control voltage of the dynamic adjustment resistance module and the voltage signal at both ends of the dynamic adjustment resistance module , calculate the current of the power supply under test, including: ； in, is the current of the power supply under test, is the drain current of MOS tube Q2 when it is in the linear region, is the current flowing through resistor R4, is the electron migration rate, is the gate oxide capacitance per unit area, is the aspect ratio of the oxide layer, is the voltage between the gate and source of MOS tube Q2, that is, the control voltage, is the threshold voltage of MOS tube Q2, is the resistance value.

7. The wide-range current measuring device according to claim 1 or 2, characterized in that: The main control module adopts the STM32f103 main control chip, and the voltage and current monitoring module adopts the LT2991 chip.

8. The wide-range current measuring device according to claim 1, characterized in that: The measured power supply, the voltage control module and the dynamic adjustment resistance module are all multi-channel, the main control module is bidirectionally connected to the voltage and current monitoring module, the output end of the main control module is connected to the input end of each voltage control module, the output end of each voltage control module is connected to the input end of each corresponding dynamic adjustment resistance module, and the output end of each dynamic adjustment resistance module is connected to the input end of the voltage and current monitoring module; The main control module is used to control the voltage and current monitoring module to simultaneously collect the initial current sizes of multiple power supplies under test, and determine the setting gear of the dynamic adjustment resistance module corresponding to each power supply under test based on the collected initial current size of each power supply under test; and according to the setting gear of each dynamic adjustment resistance module, control the corresponding voltage control module to output the corresponding control voltage to the corresponding dynamic adjustment resistance module, so that the gear of the dynamic adjustment resistance module reaches the set value, that is, the sampling resistance value is suitable for the current size of the corresponding power supply under test.

9. A wide-range current measurement method based on the wide-range current measurement device according to claim 1, characterized in that: include: Step 1: After the power supply under test is powered on, the main control module controls the voltage and current monitoring module to collect the initial current of the power supply under test; Step 2: The main control module determines the setting position of the dynamic adjustment resistance module according to the detected initial current of the measured power supply, and controls the voltage control module to output a corresponding control voltage to the dynamic adjustment resistance module according to the setting position of the dynamic adjustment resistance module; Step 3, controlling the resistance value of the dynamic adjustment resistance module to be suitable for the current of the power supply under test based on the control voltage; Step 4: Collect the voltage signal at both ends of the dynamic adjustment resistance module based on the voltage and current monitoring module ; Step 5: dynamically adjust the resistance module to control the voltage , the voltage signal at both ends of the dynamic adjustment resistance module The sampled resistance value of the dynamic adjustment resistance module is used to calculate the current of the power supply under test.

10. The wide-range current measurement method according to claim 9, characterized in that: In step 5, the voltage is controlled by the dynamic adjustment resistor module. , the voltage signal at both ends of the dynamic adjustment resistance module and dynamically adjusting the sampling resistance value of the resistance module to calculate the current of the power supply under test, and then further comprising: Repeat steps 1 to 4 to monitor the current value of the measured power supply in real time and dynamically adjust the resistance value of the dynamic adjustment resistance module according to the current gear to adapt to the current current of the measured current.

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