Signal source large current calibration method, circuit, and apparatus

Abstract

The application relates to a signal source large-current calibration method, circuit and device, which comprises the following steps: obtaining the resistance value of the sampling resistance of the kth small-current position in the calibrated k small-current positions; connecting the sampling resistance of the large-current position with the adjacent target sampling resistance in series, applying a target current to the loop after the series connection to obtain the resistance value of the sampling resistance of the calibrated large-current position; the sampling resistance of the large-current position comprises first sampling resistances and second sampling resistances adjacent to the sampling resistance of the kth small-current position, the target sampling resistance corresponding to the second sampling resistance is the sampling resistance of the kth small-current position, and the target sampling resistance corresponding to each first sampling resistance is the sampling resistance of the last calibrated large-current position; and the large-current position is calibrated based on the resistance value of the sampling resistance of the large-current position. The method can improve the calibration precision of the large-current position.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular to a method, circuit, and device for calibrating high current signals. Background Technology

[0002] A VI source, or voltage and current source, is used in semiconductor testing equipment to provide adjustable and precise voltage and current outputs, and is a core component of the testing system. With the widespread use of high-power devices, testing equipment needs to operate at high current for extended periods. However, due to factors such as device aging, environmental interference, and temperature variations, VI sources inevitably experience deviations, thus requiring periodic calibration. Different calibration methods vary in calibration accuracy, equipment size, and efficiency, leading to varying maintenance costs.

[0003] In traditional techniques, to achieve high calibration accuracy for the current, a high-precision multimeter is connected in series with the measurement circuit. The VI source board applies current, and the multimeter measures the current. The data from both are then fitted to obtain calibration parameters, thus completing the current calibration of the VI source board. However, this method is limited by the multimeter's measurement cycle. For currents above 10A, to ensure accuracy, the measurement time typically needs to be over 100ms. For a VI source board with an output power of only 10A / 10ms, this exceeds the board's output time, making accurate calibration of the VI source impossible. Summary of the Invention

[0004] Therefore, it is necessary to provide a high-current calibration method, circuit, and device for signal sources that can accurately calibrate signal sources, addressing the aforementioned technical problems.

[0005] Firstly, this application provides a method for calibrating a high-current signal source, comprising:

[0006] Obtain the resistance value of the sampling resistor for the kth small current range among the k calibrated small current ranges;

[0007] For each high current range sampling resistor, the high current range sampling resistor is connected in series with an adjacent calibrated target sampling resistor, and a target current is applied to the series circuit to obtain the calibrated resistance value of the high current range sampling resistor; wherein the high current range sampling resistor includes each first sampling resistor and a second sampling resistor adjacent to the sampling resistor of the kth low current range, the target sampling resistor corresponding to the second sampling resistor is the sampling resistor of the kth low current range, and the target sampling resistor corresponding to each first sampling resistor is the sampling resistor of the high current range calibrated in the previous test;

[0008] The high current range of the signal source is calibrated based on the resistance value of the sampling resistor of the calibrated high current range.

[0009] In one embodiment, applying the target current to the series-connected circuit to obtain the calibrated resistance value of the sampling resistor for the high-current range includes:

[0010] Apply target currents of equal magnitude and opposite direction to the series circuit to obtain the first voltages corresponding to the target sampling resistors and the second voltages of the sampling resistors at the high current level.

[0011] The actual current is obtained based on each of the first voltages and the resistance value of the target sampling resistor;

[0012] Based on the actual current and each of the second voltages, the resistance value of the sampling resistor for the calibrated high current range is obtained.

[0013] In one embodiment, after applying the target current to the series-connected circuit to obtain the calibrated resistance value of the sampling resistor for the high current range, the method further includes:

[0014] Obtain the first temperature of the sampling resistor at the high current level to which the target current is applied;

[0015] Apply a large current with a gradient change corresponding to the current range to the sampling resistor of the high current range, and collect the second temperature of the sampling resistor of the high current range.

[0016] Based on the first temperature, the second temperature, the temperature coefficient of the sampling resistor of the high current range, and the calibrated resistance value of the sampling resistor of the high current range, temperature drift calibration is performed on the sampling resistor of the high current range to obtain the target resistance value of the sampling resistor of the high current range.

[0017] In one embodiment, calibrating the high-current range of the signal source based on the resistance value of the sampling resistor of the calibrated high-current range includes:

[0018] The signal source applies a large current with a gradient change corresponding to the current range to the calibrated sampling resistor of the large current range, and obtains the third voltage of each sampling resistor of the large current range under the gradient change large current.

[0019] Based on the resistance value of the sampling resistor of each of the third voltages and the calibrated high current range, each first actual current is obtained;

[0020] Determine each of the first measured currents measured by the signal source;

[0021] By fitting each of the first actual currents and each of the first measured currents, the calibration coefficient of the high current range of the signal source is obtained.

[0022] In one embodiment, obtaining the third voltage of each sampling resistor at the high current level under the gradient change of the high current includes:

[0023] By using a multimeter connected in parallel to the sampling resistor of the high current range, the third voltage of each sampling resistor at the high current range is collected; or

[0024] The third voltage of each sampling resistor at the high current range is acquired by the calibrated ADC acquisition module.

[0025] In one embodiment, the method further includes:

[0026] The signal source applies a fourth voltage of a corresponding level to each sampling resistor, wherein the sampling resistor includes sampling resistors of each of the high current levels and sampling resistors of each of the low current levels.

[0027] The fifth voltage of the sampling resistor to which each of the fourth voltages is applied is acquired using a multimeter, and the sixth voltage of the sampling resistor to which each of the fourth voltages is applied is acquired using the ADC acquisition module.

[0028] The calibration coefficients for the corresponding voltage levels of the ADC acquisition module are obtained by fitting the fifth voltage and the sixth voltage.

[0029] In one embodiment, the method further includes:

[0030] Connect the sampling resistors of k small current ranges to the multimeter using a four-wire Kelvin connection, so that the resistance values ​​of the sampling resistors of the k small current ranges can be obtained through the multimeter.

[0031] In one embodiment, the method further includes:

[0032] A small current with a gradient change is applied to the calibrated sampling resistor of the small current range by a signal source, and the second actual current flowing through the sampling resistor of the small current range under the small current with the gradient change is obtained.

[0033] Determine each of the second measurement currents measured by the signal source;

[0034] By fitting each of the second actual currents and each of the second measured currents, the calibration coefficient of the low current range of the signal source is obtained.

[0035] Secondly, this application also provides a high-current calibration circuit for a signal source, the circuit comprising:

[0036] The calibration board includes a sampling resistor network, wherein the sampling resistor network includes k small current range sampling resistors, nk large current range sampling resistors, and a switching switch between the sampling resistors.

[0037] The signal source is used to output the signal of the corresponding range to the sampling resistor network of the calibration board;

[0038] The acquisition device is used to acquire the resistance values ​​of k small current range sampling resistors in the sampling resistor network of the calibration board, or the current or voltage of each sampling resistor in the sampling resistor network of the calibration board, based on the connection method of the sampling resistor network.

[0039] The host computer is connected to the calibration board, the signal source, and the multimeter, respectively, and is used to execute the high current calibration method of the signal source in any of the above embodiments to calibrate the high current range of the signal source.

[0040] Thirdly, this application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method in any of the above embodiments.

[0041] Fourthly, this application also provides a computer-readable and writable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method in any of the above embodiments.

[0042] Fifthly, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the method in any of the above embodiments.

[0043] The aforementioned signal source high-current calibration method, circuit, and device obtain the resistance value of the sampling resistor of the kth small current range among k calibrated small current ranges; for each high current range sampling resistor, the high current range sampling resistor is connected in series with an adjacent calibrated target sampling resistor, and a target current is applied to the series circuit to obtain the calibrated resistance value of the high current range sampling resistor; wherein the high current range sampling resistor includes each first sampling resistor and a second sampling resistor adjacent to the sampling resistor of the kth small current range, the target sampling resistor corresponding to the second sampling resistor is the sampling resistor of the kth small current range, and the target sampling resistor corresponding to each first sampling resistor is the sampling resistor of the high current range calibrated in the previous test; based on the calibrated resistance value of the high current range sampling resistor, the high current range of the signal source is calibrated. In this way, the combined calibration of the already calibrated resistors of the small current ranges is performed to calibrate the sampling resistors of the large current ranges, improving the correction accuracy of the sampling resistors, and thus improving the calibration accuracy of the high current ranges. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a circuit diagram of a high-current calibration circuit for a signal source in one embodiment;

[0046] Figure 2 This is a flowchart illustrating a high-current calibration method for a signal source in one embodiment;

[0047] Figure 3 This is a calibration circuit diagram for sampling resistors with k small current levels in one embodiment;

[0048] Figure 4 This is a circuit diagram of a high-current sampling resistor in one embodiment;

[0049] Figure 5 This is a high-current range calibration circuit diagram in one embodiment;

[0050] Figure 6 This is a circuit diagram of the ADC acquisition module performing high current range calibration in one embodiment;

[0051] Figure 7 This is a flowchart of a high-current range calibration process for an ADC acquisition module in one embodiment.

[0052] Figure 8 This is a circuit diagram for a small current range calibration in one embodiment;

[0053] Figure 9 This is a flowchart of a current range calibration method for a signal source in one embodiment;

[0054] Figure 10 A flowchart of a current range calibration method for a signal source in another embodiment;

[0055] Figure 11 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0057] It should be noted that the terms "first," "second," etc., used in this application can be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from the second element. The terms "comprising" and "having," and any variations thereof, used in this application, are intended to cover non-exclusive inclusion. The term "multiple" used in this application refers to two or more. The term "and / or" used in this application refers to one of the embodiments, or any combination of multiple embodiments.

[0058] The high-current calibration method for signal sources provided in this application can be applied to, for example... Figure 1 The signal source high-current calibration circuit shown.

[0059] The high-current calibration circuit for the signal source includes: a calibration board, a signal source, an acquisition device, and a host computer.

[0060] The calibration board includes a sampling resistor network, comprising k small-current range sampling resistors, nk large-current range sampling resistors, and a switching switch between the sampling resistors. The sampling resistors are low-temperature-drift, low-inductance resistors. The low inductance characteristic is used to avoid high-frequency distortion; manganin resistors are recommended. The low-temperature-drift characteristic is used to reduce the influence of temperature, but this influence cannot be ignored and needs to be corrected using a temperature coefficient. The switching switch can be a relay, MOSFET, or other switching device.

[0061] In this context, the current setting usually refers to a range; for example, the 1A setting can refer to -1A to 1A, and the 0.1A setting can refer to -0.1A to 0.1A. kThe corresponding current range can be the highest range among the low current ranges. R1 range is 1A (-1 to 1A), R2 range is 10A (-10 to 10A), and R2 range covers R1 range. k Gear coverage R k-1 Gear shift.

[0062] Optionally, the calibration board may also include a first control unit and a calibration bus. The calibration board is used to apply a load to the VI source board, which is the corresponding sampling resistor in the sampling resistor network. In other words, it can... Figure 1 The sampling resistors R1, R2…R in the sampling resistor network k Consider them as load resistors and sampling resistors. The switching switch is used to connect the sampling resistors in parallel or in series to the calibration bus; the calibration bus is used for connection, control, and data exchange between the calibration device and the object being calibrated.

[0063] A VI source board refers to a board with multiple output channels that supports high-precision, adjustable voltage and current four-quadrant outputs and also includes a control unit; it is also the device to be calibrated.

[0064] The signal source is used to output the corresponding range signal to the sampling resistor network of the calibration board. The signal source can be a VI source board, that is, the board to be calibrated. The board to be calibrated includes a second control unit and a VI source output. Each VI source board can support multiple output channels and multiple voltage and current ranges.

[0065] The acquisition device can be a multimeter or an ADC acquisition module. The multimeter is used for connection based on a sampling resistor network to acquire the resistance values ​​of k small current range sampling resistors in the sampling resistor network of the calibration board, or the current or voltage of each sampling resistor in the sampling resistor network of the calibration board. In other words, this multimeter is mainly used to calibrate the output voltage and current of the VI source board and the small current range sampling resistors in the calibration board. Among them, the high-precision multimeter is a high-precision, low-temperature drift measuring instrument that supports four-wire Kelvin connection and has a communication interface for measuring standard parameters such as voltage, current, and resistance. It usually refers to an eight-and-a-half-digit multimeter.

[0066] The ADC acquisition module can be located on the calibration board, and the ADC can be a high-resolution ADC. This ADC acquisition module includes follower operational amplifiers (op-amps) 1 and 2, a signal conditioning operational amplifier (op-amp) 3, and a filter. Follower op-amps 1 and 2 are used for loop impedance matching, and signal conditioning op-amp 3 is used for signal conditioning to adjust the acquisition voltage to the range of the ADC acquisition module. The filter is an anti-aliasing filter, and its cutoff frequency is more than twice the signal sampling frequency; no specific limitation is made here.

[0067] The host computer is connected to the calibration board, signal source, and multimeter, respectively, and is used to execute the high-current calibration method for the signal source in this application to calibrate the high-current range of the signal source. In other words, the host computer is the main control unit, used to control the calibration board, VI source board, and multimeter to achieve the calibration of the high-current range. The host computer includes multiple communication interfaces for processing and displaying data returned from the slave computer; this typically refers to an industrial control computer. In other embodiments, the host computer can be a PC or a microcontroller, without specific limitations.

[0068] In one exemplary embodiment, such as Figure 2 As shown, a high-current calibration method for a signal source is provided, which is applied to... Figure 1 Taking the host computer as an example, the explanation includes the following steps S202 to S206. Wherein:

[0069] S202: Obtain the resistance value of the sampling resistor for the kth small current range among the k calibrated small current ranges.

[0070] The limitations regarding the current ranges can be found above. Calibration of the k small current ranges can be achieved using a multimeter. Specifically, in this application, the small current range refers to the current value that can be directly calibrated by connecting a multimeter in series, provided that the measurement accuracy is met. The large current range refers to the current value that cannot be directly calibrated by connecting a multimeter in series, and this value is usually greater than or equal to 10A.

[0071] Specifically, the sampling resistors for k small current ranges are connected to a multimeter using a four-wire Kelvin connection, so that the resistance values ​​of the sampling resistors for the k small current ranges can be obtained through the multimeter. When calibrating the large current range, it is only necessary to obtain the resistance value of the sampling resistor for the kth small current range, that is, to obtain the resistance value of the sampling resistor corresponding to the highest current range among the small current ranges.

[0072] Furthermore, it should be noted that the low current range only covers the sampling resistor corresponding to the low current range, excluding the sampling resistor for the high current range. The number n of sampling resistors in the above sampling resistor network includes the number nk of sampling resistors for the high current range and the number of sampling resistors for the low current range. The number of sampling resistors equals the number of current ranges (the sum of high and low current ranges) and equals the number of calibration coefficient sets. One current range corresponds to one sampling resistor and one set of calibration coefficients k and b.

[0073] Specifically, in combination Figure 3 As shown, Figure 3This is a circuit diagram for a calibration circuit of sampling resistors with k small current ranges in one embodiment. In this embodiment, the host computer sends a command to the calibration board via communication line 1. The control unit on the calibration board resolves the small current ranges to be calibrated [I1, I2, I3, ... I k After that, switch the switch so that the corresponding sampling resistors [R1, R2, R3, ... R] on the calibration board are switched. k This is connected to a high-precision four-wire Kelvin multimeter. HF and LF are current lines, primarily used for applying current, while HS and LS are voltage lines, primarily used for measuring voltage. The resistance values ​​of the sampling resistors are in the following order: R1 > R2 > R3 ... > R k The corresponding current range relationships are: I1 < I2 < I3 ... < I k 'k' represents the number of resistance ranges that a high-precision multimeter can measure while meeting the required accuracy specifications. Taking a common 8.5-digit multimeter as an example, it includes 9 resistance measurement ranges: 10Ω, 100Ω, 1kΩ, 10kΩ, 100kΩ, 1MΩ, 10MΩ, 100MΩ, and 1GΩ. The calibration board's current sampling resistor includes 12 resistance ranges: 0.01Ω, 0.1Ω, 1Ω, 10Ω, 100Ω, 1kΩ, 10kΩ, 100kΩ, and 1MΩ. Ω, 10MΩ, 100MΩ, 1GΩ. If a multimeter is used in the 10Ω range to measure 0.01Ω and 0.1Ω resistors, the relative deviation is 200ppm and 100ppm respectively, while the deviation for the other resistors is 10ppm. The required accuracy is 30ppm, so the appropriate resistance range is k = 12 - 2 = 10. The resistance value data measured by the multimeter is sent back to the host computer via communication line 2 and written to the storage medium, completing the sampling resistance calibration for the small current range.

[0074] Specifically, a small current is applied to the multimeter at multiple ranges, and the voltage across the sampling resistor at each range is measured. This allows the calculation of the resistance value of each sampling resistor (displayed on the multimeter as R1, R2…R…). k The resistance value is calculated using a multimeter. Each small current range corresponds to a sampling resistor, which is written to a storage medium, such as the hard drive of a host computer. Taking one of the sampling resistors as an example, a certain current is applied to the multimeter, and then the voltage is measured internally. Finally, the resistance is calculated using a certain algorithm, such as voltage / current, and the resistance value is displayed. At this time, the voltage and current values ​​inside the multimeter are not displayed.

[0075] In this way, when measuring small current sampling resistors (resistance values ​​are generally above 10Ω), the influence of wire impedance is avoided by using a four-wire Kelvin connection.

[0076] S204: For the sampling resistor of each high current range, connect the sampling resistor of the high current range in series with the adjacent calibrated target sampling resistor, and apply the target current to the series circuit to obtain the resistance value of the calibrated high current range sampling resistor; wherein the sampling resistor of the high current range includes each first sampling resistor and a second sampling resistor adjacent to the sampling resistor of the kth low current range, the target sampling resistor corresponding to the second sampling resistor is the sampling resistor corresponding to the kth low current range, and the target sampling resistor corresponding to each first sampling resistor is the sampling resistor of the high current range calibrated in the previous test.

[0077] The calibration of each high current range first requires calibrating the sampling resistor for that high current range. In this application, a test resistor is introduced for the calibration of the sampling resistor for the high current range; this test resistor is the adjacent, already calibrated target sampling resistor. For example, the sampling resistors for each high current range include the sampling resistor for each first sampling resistor (R...). k+2 ...R n ) and the second sampling resistor (R) adjacent to the sampling resistor of the k-th small current level. k+1 For the second sampling resistor R k+1 The corresponding test resistor is the sampling resistor R corresponding to the kth small current range. k The first sampling resistor R k+2 The accompanying resistor is the second sampling resistor R. k+1 The first sampling resistor R n The accompanying resistor is the first sampling resistor R. n-1 .

[0078] In this circuit, the sampling resistor of the high current range is connected in series with the adjacent calibrated target sampling resistor, and the target current is applied to the series circuit. Since the target sampling resistor has been calibrated, the current flowing through the sampling resistor of the high current range and the current of the target sampling resistor can be obtained. Then, based on the measured voltage of the sampling resistor of the high current range, the resistance value of the sampling resistor of the high current range can be determined.

[0079] S206: Based on the resistance value of the sampling resistor of the calibrated high current range, calibrate the high current range of the signal source.

[0080] After determining the resistance value of the sampling resistor for the calibrated high-current range, a corresponding high current is applied to the sampling resistor. Finally, the voltages under the applied high current are collected. Based on these voltages and the sampling resistor for the high-current range, the calibration coefficients for that range are determined and stored, thus completing the high-current range calibration of the signal source. Furthermore, it should be noted that after completing the calibration of one high current range, the calibration process can continue to the next high current range until all high current ranges are calibrated.

[0081] One point to note is that, in this application, applying a large current at a corresponding level, applying a small current at a corresponding level, or applying a current at a corresponding level all refer to applying a current within the range of that level. For example, a 1A level can refer to -1A to 1A, 0.1A can refer to -0.1A to 0.1A, and a current at a 1A level refers to a current within the range of -1A to 1A.

[0082] The above-described high-current calibration method for signal sources obtains the resistance value of the sampling resistor for the kth small current range among the k calibrated small current ranges. For each high-current range sampling resistor, the high-current range sampling resistor is connected in series with an adjacent calibrated target sampling resistor, and a target current is applied to the series circuit to obtain the calibrated resistance value of the high-current range sampling resistor. The high-current range sampling resistor includes each first sampling resistor and a second sampling resistor adjacent to the sampling resistor of the kth small current range. The target sampling resistor corresponding to the second sampling resistor is the next-level sampling resistor of the kth small current range, and the target sampling resistor corresponding to each first sampling resistor is the sampling resistor of the previously calibrated high-current range. Based on the resistance value of the calibrated high-current range sampling resistor, the high-current range of the signal source is calibrated. This combined calibration of the already calibrated resistors of the small current ranges improves the calibration accuracy of the sampling resistors.

[0083] In some optional embodiments, applying a target current to the series-connected loop to obtain the resistance value of the calibrated high-current sampling resistor includes: applying target currents of equal magnitude and opposite direction to the series-connected loop to obtain each first voltage corresponding to the target sampling resistor and each second voltage of the high-current sampling resistor; obtaining the actual current based on each first voltage and the resistance value of the target sampling resistor; and obtaining the resistance value of the calibrated high-current sampling resistor based on the actual current and each second voltage.

[0084] The target current is the current corresponding to the range. This target current is the current corresponding to the range of the adjacent calibrated target sampling resistor, that is, any current within the range of the adjacent calibrated target sampling resistor. The only difference is that the two target currents are in opposite directions, but their magnitudes are the same.

[0085] Specifically, in combination Figure 4 As shown, Figure 4 This is a circuit diagram for calibrating a high-current sampling resistor in one embodiment. In this embodiment, the calibration of the high-current sampling resistor also includes a switching section for a companion resistor. The companion resistor is a calibrated current sampling resistor, and the sampling resistor R... k+1 That is, before calibrating the sampling resistor at the high current range, the host computer sends a command to the control unit of the calibration board to control the switching switch between the sampling resistors to engage, so that the sampling resistor R at the high current range... k+1 With the target sampling resistor R k Forming a series structure (here, with resistor R) k+1 and resistance R k Taking this as an example, in other embodiments, the target sampling resistor can be R. k+1 The sampling resistor for the high current range is R. k+2 And so on (no further limitations are specified here). Then, to eliminate the influence of thermoelectric potential, the VI source board applies target currents I of equal magnitude and opposite direction at certain levels. + k I - k High-precision multimeters were used to measure R respectively. k R k+1 The voltage at both ends, including each first voltage U + mk U - mk and each second voltage U + mk+1 U - mk+1 According to the formula:

[0086]

[0087] Find the sampling resistor R through the small current range. k The actual current. Then switch the multimeter's measurement circuit and measure the voltage across the sampling resistor in the high current range, i.e., each second voltage U. + mk+1 U - mk+1 According to the formula

[0088]

[0089] The actual sampling resistor R for the high current range can be obtained. k+1 Similarly, the resistance [R] to be corrected can be measured. k+1 ,R k+2 ,R k+3 ,...R n The resistance value is written to the storage medium, that is, to the hard drive of the host computer.

[0090] The aforementioned low current range sampling resistor R k Replace with a high current range resistor R k+1 Then, the high current range resistor R can be achieved. k+2 The calibration is performed, but it should be noted that the target current should be adjusted to the high current setting for the resistor R. k+1 The corresponding range current. In other words, when calibrating with a high-current resistor, the corresponding current is the current of the range corresponding to the calibrated test resistor.

[0091] In the above embodiments, the calibration accuracy of the sampling resistor is improved by introducing a test resistor and a switching switch. When calibrating a high-current sampling resistor (typically below 10Ω), the actual current flowing through the entire branch is indirectly obtained by connecting the test resistor in series and measuring the voltage with a high-precision multimeter. Then, based on the principle that the thermoelectric potential remains constant, the voltage across the high-current sampling resistor is measured by applying forward and reverse currents. Finally, the actual resistance value is calculated using Ohm's law, eliminating the influence of the thermoelectric potential of the sampling resistor and reducing measurement errors. Calculations show that this method improves accuracy by 96% compared to directly measuring the resistance with a multimeter when calibrating a 40A high-current resistor. The larger the current and the smaller the sampling resistor, the more significant the beneficial effect. This method not only reduces the probability of calibration failure but also broadens the application range of high-precision multimeters in current calibration, enabling high-efficiency and automated calibration.

[0092] In some optional embodiments, after applying a target current to the series circuit and obtaining the calibrated resistance value of the sampling resistor at the high current level, the method further includes: acquiring a first temperature of the sampling resistor at the high current level to which the target current is applied; applying a high current with a gradient change corresponding to the high current level to the sampling resistor at the high current level and acquiring a second temperature of the sampling resistor at the high current level; and performing temperature drift calibration on the sampling resistor at the high current level based on the first temperature, the second temperature, the temperature coefficient of the sampling resistor at the high current level, and the calibrated resistance value of the sampling resistor at the high current level to obtain the target resistance value of the sampling resistor at the high current level.

[0093] In this embodiment, considering that the resistance value of the sampling resistor corresponding to the high current range is easily affected by temperature, temperature measurement is also included in the high current range sampling resistor calibration. Optionally, a temperature sensor, such as a PT1000, thermocouple, or dedicated temperature measurement chip, is installed in the central heating area of ​​the sampling resistor surface. This sensor is fed back to the host computer via a specific acquisition link. The host computer compensates for the measured value of the sampling resistor at the high current range based on the acquired temperature data to reduce the nonlinear effect of the sampling resistor under high current excitation. The compensation method is referenced by the following formula:

[0094] R′ k+1 =R k+1 [1+α(T-T0)]

[0095] Where R' k+1 R is the target resistance value of the sampling resistor for the high current range. k+1 The correction resistance value [R] is obtained by measuring the accompanying resistance. k+1 ,R k+2 ,R k+3 ,...R n ], α is the known temperature coefficient of resistance of the sampling resistor, which is constant; T is the sampling resistor R under high current excitation. k+1 The temperature value, also known as the second temperature, is the sampling resistor R at the corresponding high current range. k+1 The temperature value, T0, is the sampling resistor R under small current excitation. k+1 The temperature value, also known as the first temperature, is where the small current excitation is the target current mentioned above. Here, it is called a small current only in comparison with the current of the large current range.

[0096] In addition, it should be noted that in the low current range, the current value is relatively small, the temperature rise is small, and there is no need to correct the temperature drift of the sampling resistor in the low current range.

[0097] In the above embodiments, temperature drift of the sampling resistor at the high current range is corrected by temperature adjustment, thereby improving the calibration accuracy of the sampling resistor at the high current range. This reduces the impact of temperature changes while ensuring the output accuracy and calibration efficiency of the VI source board, all within the constraints of equipment size and cost.

[0098] In some optional embodiments, the high-current range of the signal source is calibrated based on the resistance value of the sampling resistor of the calibrated high-current range, including: applying a high current with a gradient change corresponding to the range to the sampling resistor of the calibrated high-current range through the signal source, and obtaining each third voltage of the sampling resistor of the high-current range under the gradient change high current; obtaining each first actual current based on each third voltage and the resistance value of the sampling resistor of the calibrated high-current range; determining each first measured current measured by the signal source; and fitting each first actual current and each first measured current to obtain the calibration coefficient of the high-current range of the signal source.

[0099] After calibrating the sampling resistors for the high-current range, the corresponding high-current range can be calibrated. First, disconnect the series switch between the sampling resistors, then control the switch on the calibration board to connect the high-precision multimeter in parallel to the sampling resistor circuit of the current range to be measured. Figure 5 , Figure 5 This is a high-current range calibration circuit diagram in one embodiment. In this embodiment, for high current range I... k+1 The VI source feeds the corrected sampling resistor [R'] onto the calibration board at a certain range ratio. k+1 ,R' k+2 ,R' k+3 ,...R' n Apply large currents with gradient changes corresponding to the respective gear levels [a1*I] k+1 ,a2*I k+1 ,a3*I k+1 ,...a q *I k+1 ], where -1≤a q ≤1, switch the multimeter to the voltage range, and measure the third voltage as [U m1 U m2 U m3 ,...U mq According to the formula

[0100]

[0101] Converted to a current array, i.e., the first actual current [I m1 ,I m2 ,I m3 ,...I mq Then, the first measured current [I] is obtained from the VI source board. t1 ,I t2 ,I t3 ,...I tq The least squares method is used to fit the data to obtain a functional expression between the two, and the corresponding calibration coefficients are then written to the storage medium. Where R' k+2High current range coverage R' k+1 High current setting, R' n The corresponding high current setting is the maximum setting.

[0102] In some optional embodiments, acquiring each third voltage of the sampling resistor at the high current range under a gradient-changing high current includes: acquiring each third voltage of the sampling resistor at the high current range using a multimeter connected in parallel to the sampling resistor at the high current range; or acquiring each third voltage of the sampling resistor at the high current range using a calibrated ADC acquisition module.

[0103] In this embodiment, the third voltage can be measured by a multimeter or by an ADC acquisition module. If the measurement is performed by an ADC acquisition module, the ADC acquisition module needs to be calibrated first.

[0104] In some alternative embodiments, the high-precision multimeter can also be replaced by a high-resolution ADC acquisition module integrated on the calibration board. For example... Figure 6 As shown, the ADC acquisition module includes a switching switch connected across the sampling resistors, follower operational amplifiers op1 and op2, signal amplification operational amplifier op3, a filter, and a high-resolution ADC. The method further includes: applying a fourth voltage corresponding to each sampling resistor level to each sampling resistor via a signal source, wherein the sampling resistors include sampling resistors for major current levels and sampling resistors for minor current levels; acquiring a fifth voltage of each sampling resistor with applied fourth voltage using a multimeter; acquiring a sixth voltage of each sampling resistor with applied fourth voltage using the ADC acquisition module; and fitting the fifth and sixth voltages to obtain the calibration coefficients for the corresponding voltage levels of the ADC acquisition module.

[0105] When replacing a multimeter with a high-resolution ADC acquisition module, the voltage measurement function of the ADC acquisition module must first be calibrated. The VI source is fed into the sampling resistors [R1, R2, R3, ... R on the calibration board at specific range ratios.] k ,R' k+1 ,R' k+2 ,R' k+3 ,...R' n Apply a voltage level to each, for example, apply a fourth voltage [a1*U1, a2*U1, a3*U1, ... a] to R1. q *U1], towards R' k+1 Apply a fourth voltage [a1*U] k+1 ,a2*U k+1 ,a3*U k+1 ,...a q *U k+1The multimeter and high-resolution ADC acquisition module were simultaneously switched to the voltage range, and the measured voltages were the fifth voltage [U]. m1 U m2 U m3 ,...U mq ], sixth voltage [U adc1 U adc2 U adc3 ,...U adcq Then, by performing a least-squares fit between the two, the calibration coefficient k corresponding to each voltage level can be obtained. uadc and b uadc And write it to the storage medium.

[0106] When acquiring the third voltage through the ADC acquisition module, such as Figure 7 As shown, disconnect the multimeter measurement circuit, and apply a gradient-changing current to the sampling resistor, for example, apply a gradient-changing current [a1*I1, a2*I1, a3*I1, ... a] to the sampling resistor R1. q *I1], to the sampling resistor R' n Applying a gradient current [a1*I n ,a2*I n ,a3*I n ,...a q *I n Then the ADC measures the voltage [U] flowing through the sampling resistor. adc1 U adc2 U adc3 ,...U adcq According to the current gear sampling resistor R' n Calculate the actual current I adcq =U adcq / R' n Then, based on the fitting algorithm and the current I measured by the VI source, tq Establish the functional relationship, obtain the current range calibration coefficient, and write it to the storage medium.

[0107] The above embodiments can eliminate the impact of the long reading time of traditional multimeters, reduce the probability of board damage, and reduce the number of calibration retry times, thereby improving calibration efficiency.

[0108] In some optional embodiments, the above method further includes calibration of the low current level, specifically in conjunction with... Figure 8 , Figure 8The following is a circuit diagram of a low current range calibration circuit in one embodiment. The calibration of the low current range includes: applying a gradient-changing low current to the sampling resistor of the calibrated low current range through a signal source, and obtaining each second actual current flowing through the sampling resistor of the low current range under the gradient-changing low current; determining each second measured current measured by the signal source; and fitting each second actual current and each second measured current to obtain the calibration coefficient of the low current range of the signal source.

[0109] Assume that the VI source has the following current levels [I1, I2, I3, ... I k ,I k+1 ,I k+2 ,...I n The corresponding current sampling resistors are [R1, R2, R3, ... R k ,R k+1 ,R k+2 ,......R n ], where n and k are both positive integers, n represents the number of current ranges on the VI source board, and n≥k. First, the host computer controls the switch on the calibration board to connect the high-precision multimeter in series with the sampling resistor circuit of the current range to be measured. Then, for the measurable small current range I k The VI source feeds the sampler R on the calibration board at a certain level. k Apply a small current with a gradient change [a1*I] k ,a2*I k ,a3*I k ,...a q *I k ], where -1≤a q ≤1, where q is a positive integer. The larger the value, the more calibration items are involved, and the longer the calibration time. In engineering, 2 to 10 points are typically used. The second actual current measured by the multimeter is [I m1 ,I m2 ,I m3 ,...I mq The second measured current of the VI source board is [I]. t1 ,I t2 ,I t3 ,...I tq At this point, the functional relationship between the current measured by the multimeter and the current measured by the VI source board can be established by least squares fitting, thereby obtaining the calibration coefficients and writing them to the storage medium. The goal of least squares fitting is to find a straight line y = kx + b such that the sum of the squares of the perpendicular distances (residuals) from all data points to this line is minimized. The dataset is [(I t1 I m1 ),(I t2 I m2 ),(It3 I m3 ),...(I tq I mq The residual sum of squares S is:

[0110]

[0111] The slope k and intercept b are determined by minimizing the sum of squared residuals, where k and b are the calibration coefficients.

[0112]

[0113] For ease of understanding, the following is combined Figure 9 As shown, Figure 9 This is a flowchart of a current range calibration method for a signal source in one embodiment. In this embodiment, the calibration method includes:

[0114] First, the sampling resistors for the low current range are calibrated, including: using a four-wire Kelvin connection method, measuring the sampling resistors [R1, R2, R3, ... R] for the low current range within the measurement range using a high-precision multimeter. k The actual value of the sampling resistor is obtained and written to the storage medium.

[0115] Secondly, the low current range is calibrated, including: the VI source (signal source) supplying the calibrated low current sampling resistor value R. k Apply current excitation at the corresponding gear level with gradient changes [a1*I] k ,a2*I k ,a3*I k ,...a q *I k ], where -1≤a q ≤1, where q is a positive integer representing the number of output points; the larger the value, the closer the range is to the standard value. Switch the multimeter to the current range and connect it in series with the circuit to measure the actual current flowing through the sampling resistor [I]. m1 ,I m2 ,I m3 ,...I mq ], and the current [I] measured by the VI source t1 ,I t2 ,I t3 ,...I tq The calibration coefficients are obtained by least squares fitting and written to the storage medium to complete the small current calibration.

[0116] Third, calibrate the sampling resistor for the high current range, including: connecting the sampling resistor for the low current range in series with the sampling resistor for the adjacent high current range, and applying small currents I of equal magnitude but opposite direction to the circuit. +k I - k Switch the multimeter to the voltage setting and measure the current flowing through the known sampling resistor R. k voltage U + mk U - mk The actual current is calculated, and then the multimeter measurement circuit is switched to measure the sampling resistor R in the high current range. k+1 Voltage U at both ends + mk+1 U - mk+1 Then, the actual resistance value of the high current range is calculated based on the actual current.

[0117] Fourth, the sampling resistor for the high current range is corrected using temperature drift compensation to obtain the corrected resistance value [R']. k+1 ,R' k+2 , R' k+3 , R' n ].

[0118] Fifth, the sampling resistor R' of the VI source to the high current range. k+1 Applying a large current with gradient variation [a1*I k+1 ,a2*I k+1 ,a3*I k+1 ,...a q *I k+1 Switch the multimeter to the voltage setting and measure the voltage U flowing through the sampling resistor. m According to I m =U m / R calculates the actual current [I] m1 ,I m2 ,I m3 ,...I mq Then, the current [I] measured by the VI source is compared with the current [I]. t1 ,I t2 ,I t3 ,...I tq The calibration coefficients are obtained by performing least squares fitting, and so on, R' can be obtained respectively. k+2 ,R' k+3 ,R' k+4 ,...R' n The corresponding calibration coefficients are then written to the storage medium.

[0119] Furthermore, the calibration coefficients mentioned above all include a set of coefficients k and b. Each current range has a set of calibration coefficients. Therefore, when there are n current ranges, the current calibration coefficients are n sets, such as [(k1,b1),(k2,b2),(k3,b3),...(kn ,b n After the host computer writes the calibration coefficients to the storage medium, each board will call these n sets of coefficients through the communication line during the calibration current process and write them to the board's own non-volatile memory, such as EEPROM, FLASH, etc.

[0120] Taking the low current range I1 corresponding to R1 as an example, assuming the calibration coefficients for this range are k1 and b1, when the set value of the VI source output current is a certain value I in the I1 range... set (-I1≤I set When I1 is less than or equal to ≤1, the VI source is directly adjusted using calibration coefficients k1 and b1 before output. The setpoint is then corrected to I'. set =k1*I set +b1 automatically brings the output current value closer to the target value. The same principle applies to higher current ranges.

[0121] In another embodiment, combined with Figure 10 As shown, Figure 10 The flowchart below shows a current range calibration method for a signal source in another embodiment. In this embodiment, the calibration method includes:

[0122] First, the sampling resistors for the low current range are calibrated, including: using a four-wire Kelvin connection method, measuring the sampling resistors [R1, R2, R3, ... R] for the low current range within the measurement range using a high-precision multimeter. k The actual value of the sampling resistor is obtained and written to the storage medium.

[0123] Secondly, the low current range is calibrated, including: the VI source (signal source) supplying the calibrated low current sampling resistor value R. k Apply current excitation at the corresponding gear level with gradient changes [a1*I] k ,a2*I k ,a3*I k ,...a q *I k ], where -1≤a q ≤1, where q is a positive integer representing the number of output points; the larger the value, the closer the range is to the standard value. Switch the multimeter to the current range and connect it in series with the circuit to measure the actual current flowing through the sampling resistor [I]. m1 ,I m2 ,I m3 ,...I mq ], and the current [I] measured by the VI source t1 ,I t2 ,I t3 ,...I tqThe calibration coefficients are obtained by least squares fitting and written to the storage medium to complete the small current calibration.

[0124] Third, calibrate the sampling resistor for the high current range, including: connecting the sampling resistor for the low current range in series with the sampling resistor for the adjacent high current range, and applying small currents I of equal magnitude but opposite direction to the circuit. + k I - k Switch the multimeter to the voltage setting and measure the current flowing through the known sampling resistor R. k voltage U + mk U - mk The actual current is calculated, and then the multimeter measurement circuit is switched to measure the sampling resistor R in the high current range. k+1 Voltage U at both ends + mk+1 U - mk+1 Then, the actual resistance value of the high current range is calculated based on the actual current.

[0125] Fourth, the sampling resistor for the high current range is corrected using temperature drift compensation to obtain the corrected resistance value [R']. k+1 ,R' k+2 , R' k+3 , R' n ].

[0126] Fifth, the source-to-sampling resistors of VI [R1,R2,R3,...R k ,R' k+1 ,R' k+2 , R' k+3 , R' n Apply gradient-varying voltage excitation U respectively k Switch the multimeter to voltage mode to measure the voltage U across the sampling resistor. m Subsequently, the high-resolution ADC acquisition module measures the voltage U across the sampling resistor. adc U is obtained according to the fitting algorithm m with U adc The calibration coefficients between these coefficients are used to complete the voltage calibration of the ADC.

[0127] Sixth, disconnect the multimeter measurement circuit, and direct the source VI to the sampling resistor R'. n Apply gradient-changing currents [a1*I] n ,a2*I n ,a3*I n ,..a q *I nThe ADC acquisition module measures the voltage [U] flowing through the sampling resistor. adc1 U adc2 U adc3 ,...U adcq According to the current gear sampling resistor R' n Calculate the actual current I adcq =U adcq / R' n Then, based on the fitting algorithm and the current I measured by the VI source, tq Establish the functional relationship, obtain the current range calibration coefficient, and write it to the storage medium.

[0128] Specifically, when an ADC acquisition module is used to replace the multimeter for current calibration, the current calibration coefficient obtained by the ADC acquisition module is [(k 1_adc ,b 1_adc ),(k 2_adc ,b 2_adc ),(k 3_adc ,b 3_adc ),...(k n_adc ,b n_adc A total of n sets of data are written to the non-volatile memory of the VI source board. When the set value of the VI source output current is I... k+1 A certain value I in the gear position set (-I k+1 ≤I set ≤I k+1 When ), the VI source is directly calibrated using the calibration coefficient k before output. k+1_adc ,b k+1_adc Go and adjust the setting value; at this point, the setting value is corrected to I'. set =k k+1_adc *I set +b k+1_adc This allows the output current value to automatically approach the target value. It should be noted that before using the ADC acquisition module for VI source current calibration, the calibration board must perform at least one ADC voltage range calibration. Only then can the current calculated from the voltage by the ADC acquisition module be considered accurate. The voltage range calibration coefficients of the ADC acquisition module are written to the non-volatile memory of the calibration board. n sampling resistors correspond to n sets of voltage calibration coefficients for the ADC acquisition module [(k u1 ,b u1 ),(k u2 ,b u2 ),(k u3 ,b u3 ),...(k un ,b un )).

[0129] The above embodiments do not require a dedicated shunt to collect current; high-current automatic calibration can be achieved solely through a high-precision resistor. The inductive and capacitive reactance components are relatively small, resulting in a smaller size and easier integration into semiconductor testing equipment, thus improving scalability. Furthermore, addressing the issue that the measurement time of a high-precision multimeter may exceed the maximum output current time of the VI source when calibrating high currents, the methods of converting current to voltage and performing multi-step calibration, as well as extending the ADC acquisition, reduce the board damage rate, thereby lowering maintenance costs.

[0130] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps. It is understood that the steps in different embodiments can be freely combined as needed, and all non-contradictory solutions formed by such combinations are within the scope of protection of this application.

[0131] Based on the same inventive concept, this application also provides a signal source high-current calibration device for implementing the signal source high-current calibration method described above. The solution provided by this device is similar to the implementation described in the above method; therefore, the specific limitations in one or more embodiments of the signal source high-current calibration device provided below can be found in the limitations of the signal source high-current calibration method described above, and will not be repeated here.

[0132] In one exemplary embodiment, a computer device is provided, which may be a host computer, and its internal structure diagram may be as follows: Figure 11As shown, the computer device includes a processor, memory, input / output interfaces, a communication interface, a display unit, and an input device. The processor, memory, and input / output interfaces are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interfaces. The processor provides computing and control capabilities. The memory includes non-volatile storage media and main memory. The non-volatile storage media stores the operating system and computer programs. The main memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The input / output interfaces are used for exchanging information between the processor and external devices. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, Near Field Communication (NFC), or other technologies. When executed by the processor, the computer program implements a high-current calibration method for a signal source. The display unit is used to form a visually visible image and can be a display screen, a projection device, or a virtual reality imaging device. The display screen can be an LCD screen or an e-ink screen. The input device of the computer device can be a touch layer covering the display screen, or buttons, trackballs, or touchpads set on the casing of the computer device, or external keyboards, touchpads, or mice, etc.

[0133] Those skilled in the art will understand that Figure 11 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0134] In one embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0135] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the steps in the above method embodiments.

[0136] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0137] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0138] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0139] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for calibrating a high-current signal source, characterized in that, include: Obtain the resistance value of the sampling resistor for the kth small current range among the k calibrated small current ranges; For each high current range sampling resistor, the sampling resistor of the high current range is connected in series with the adjacent calibrated target sampling resistor, and the target current is applied to the series circuit to obtain the resistance value of the calibrated high current range sampling resistor. The sampling resistor for the high current range includes each first sampling resistor and a second sampling resistor adjacent to the sampling resistor for the kth low current range. The target sampling resistor corresponding to the second sampling resistor is the sampling resistor for the kth low current range, and the target sampling resistor corresponding to each first sampling resistor is the sampling resistor for the high current range calibrated in the last calibration. The high current range of the signal source is calibrated based on the resistance value of the sampling resistor of the calibrated high current range.

2. The method according to claim 1, characterized in that, The process of applying the target current to the series-connected circuit to obtain the calibrated resistance value of the sampling resistor for the high-current range includes: Apply target currents of equal magnitude and opposite direction to the series circuit to obtain the first voltages corresponding to the target sampling resistors and the second voltages of the sampling resistors at the high current level. The actual current is obtained based on each of the first voltages and the resistance value of the target sampling resistor; Based on the actual current and each of the second voltages, the resistance value of the sampling resistor for the calibrated high current range is obtained.

3. The method according to claim 1, characterized in that, After applying the target current to the series-connected circuit and obtaining the calibrated resistance value of the sampling resistor for the high-current range, the process further includes: Obtain the first temperature of the sampling resistor at the high current level to which the target current is applied; Apply a large current with a gradient change corresponding to the current range to the sampling resistor of the high current range, and collect the second temperature of the sampling resistor of the high current range. Based on the first temperature, the second temperature, the temperature coefficient of the sampling resistor of the high current range, and the calibrated resistance value of the sampling resistor of the high current range, temperature drift calibration is performed on the sampling resistor of the high current range to obtain the target resistance value of the sampling resistor of the high current range.

4. The method according to claim 1, characterized in that, The calibration of the high-current range of the signal source based on the resistance value of the sampling resistor after calibration includes: The signal source applies a large current with a gradient change corresponding to the current range to the calibrated sampling resistor of the large current range, and obtains the third voltage of each sampling resistor of the large current range under the gradient change large current. Based on the resistance value of the sampling resistor of each of the third voltages and the calibrated high current range, each first actual current is obtained; Determine each of the first measured currents measured by the signal source; By fitting each of the first actual currents and each of the first measured currents, the calibration coefficient of the high current range of the signal source is obtained.

5. The method according to claim 4, characterized in that, Obtaining the third voltage of each sampling resistor at the high current level under the gradient change of the high current includes: By using a multimeter connected in parallel to the sampling resistor of the high current range, the third voltage of each sampling resistor at the high current range is collected; or The third voltage of each sampling resistor at the high current range is acquired by the calibrated ADC acquisition module.

6. The method according to claim 5, characterized in that, The method further includes: The signal source applies a fourth voltage of a corresponding level to each sampling resistor, wherein the sampling resistor includes sampling resistors of each of the high current levels and sampling resistors of each of the low current levels. The fifth voltage of the sampling resistor to which each of the fourth voltages is applied is acquired using a multimeter, and the sixth voltage of the sampling resistor to which each of the fourth voltages is applied is acquired using the ADC acquisition module. The calibration coefficients for the corresponding voltage levels of the ADC acquisition module are obtained by fitting the fifth voltage and the sixth voltage.

7. The method according to any one of claims 1 to 6, characterized in that, The method further includes: Connect the sampling resistors of k small current ranges to the multimeter using a four-wire Kelvin connection, so that the resistance values ​​of the sampling resistors of k small current ranges can be obtained through the multimeter.

8. The method according to any one of claims 1 to 6, characterized in that, The method further includes: A small current with a gradient change is applied to the calibrated sampling resistor of the small current range by a signal source, and the second actual current flowing through the sampling resistor of the small current range under the small current with the gradient change is obtained. Determine each of the second measurement currents measured by the signal source; By fitting each of the second actual currents and each of the second measured currents, the calibration coefficient of the low current range of the signal source is obtained.

9. A high-current calibration circuit for a signal source, characterized in that, The circuit includes: The calibration board includes a sampling resistor network, wherein the sampling resistor network includes k small current range sampling resistors, nk large current range sampling resistors, and a switching switch between the sampling resistors. The signal source is used to output the signal of the corresponding range to the sampling resistor network of the calibration board; The acquisition device is used to acquire the resistance values ​​of k small current range sampling resistors in the sampling resistor network of the calibration board, or the current or voltage of each sampling resistor in the sampling resistor network of the calibration board, based on the connection method of the sampling resistor network. The host computer is connected to the calibration board, the signal source, and the multimeter, respectively, and is used to execute the high current calibration method of the signal source according to any one of claims 1 to 8, so as to calibrate the high current range of the signal source.

10. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1-8.

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