Fast matching method and system for gain consistency of multi-channel weak current test

Abstract

The application discloses a kind of fast matching method and system of multi-channel weak current test gain consistency, it is related to electronic component testing technical field.The matching method includes traceability calibration stage, utilizes internal integrated programmable precision current source to carry out multi-range gear fine calibration to a specified channel, establishes gold channel as precision reference;Fast matching stage, a stable reference current is injected into all test channels by high-speed polling through switch matrix, and the response value of gold channel is used as reference, the consistency proportion coefficient of each channel is calculated;Correction application stage, in actual measurement, the original data of each channel is multiplied by its exclusive proportion coefficient, and the high consistency result after correction is output.The matching system includes the hardware and control program of executing the above matching method.The application is used to realize the unity of precision and multi-channel consistency, calibration process is fully automatic, fast, shorten whole system calibration time, improve instrument production efficiency and factory quality.

Description

Technical Field

[0001] This invention relates to the field of electronic component testing technology, and in particular to a rapid matching method and system for gain consistency in multi-channel weak current testing. Background Technology

[0002] Multi-layer ceramic capacitors (MLCCs) are characterized by their small size, high capacitance density, excellent high-frequency characteristics, non-polarity, low loss, high reliability, and wide voltage and temperature range. Furthermore, their manufacturing process is mature, their price is low, and they have a wide range of applications, making them one of the most widely used capacitor types in modern electronic equipment. To meet the demands of large production capacity and improve production efficiency, manufacturers commonly use multi-channel testing systems to test and sort MLCC products for electrical parameters such as capacitance, loss tangent, and leakage current.

[0003] In practical online high-speed testing applications, because the leakage current testing process requires time to establish charging and discharging circuits, the measurement method generally does not employ the multi-channel scanning measurement method used in capacitance and loss tangent testing. Each leakage current test channel is equipped with independent transimpedance amplifiers (TIAs), gain amplifiers, signal filters, and analog-to-digital converters (ADCs) and other signal processing components. The equipment uses a multi-channel testing system to independently measure the leakage current of the tested products at the milliamp, microamp, nanoamp, and even picoamp levels before sorting them according to the same process settings. The most commonly used method in the industry is the single-point threshold comparison method, which uses extremely short detection time. It often detects the current decay trend rather than the pure leakage current value of MLCCs, and the detection result includes a certain proportion of polarization current. Although this type of testing and sorting method has high requirements for absolute measurement accuracy, it is not the ultimate requirement. Instead, it has extremely high requirements for the consistency of multi-channel test results, because even small deviations between channels can directly lead to product misjudgment and affect yield.

[0004] Taking the most widely used eight-channel capacitor testing and sorting equipment in the industry as an example, the consistency of the histogram mean distribution of its multi-channel leakage current test results is not ideal, often failing to meet the consistency requirement of less than 3% of the mean distribution center value proposed by some major MLCC manufacturers. In the production of multi-channel test circuits or instruments, existing technologies mostly adopt the following two methods for calibration: one is to perform independent high-precision calibration on each channel. Although this method can improve the absolute accuracy of the test circuit, it is time-consuming and has extremely high requirements for the absolute precision of components, making it difficult to meet the needs of production line efficiency and product cost-effectiveness; the other is to use a simple software normalization algorithm, which can improve multi-channel consistency, but lacks anchoring to the true value and cannot overcome the common temperature drift and time drift of the system. Therefore, there is an urgent need for a production calibration solution that can simultaneously take into account accuracy, consistency, efficiency, and cost-effectiveness. Summary of the Invention

[0005] The purpose of this invention is to provide a rapid matching method and system for the gain consistency of multi-channel weak current testing, so as to achieve high consistency and high accuracy of multi-channel weak current testing system and solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: First aspect, a rapid matching method for gain consistency of multi-channel weak current testing, comprising the following steps: S1: Hardware zero-point adjustment: Control each test channel and its corresponding test fixture path, and adjust the zero-adjustment component connected to the transimpedance amplifier of each channel respectively in the open circuit state of the test fixture electrode, so that the output response value of each channel falls into the preset zero-point target range.

[0007] S2: Establishment of the Golden Channel: At at least one range setting, at least two standard micro-currents of different values ​​are applied to the selected test channel through the programmable precision current source integrated within the system. Based on the response of the test channel to the at least two standard micro-currents, the channel gain parameters are accurately calculated to minimize the error between the output response and the theoretical value, thus establishing the golden channel as the absolute accuracy benchmark of the system.

[0008] S3: Multi-channel fast matching: At at least one range setting, control the programmable precision current source to output a fixed reference micro-current, and apply the reference micro-current simultaneously or sequentially to all test channels, including the gold channel, through a multiplexed switch matrix. Based on the response value of the gold channel, calculate and store the consistency ratio coefficient of the remaining channels.

[0009] S4: Measurement Data Correction Application: During actual measurement, the consistency ratio coefficient corresponding to each channel is called to correct the original test data of the channel in real time and output the measurement result after consistency correction.

[0010] Optionally, in the S2 gold channel establishment step, the programmable precision current source consists of a programmable reference voltage source and a resistor array with precisely calibrated resistance values ​​switched by relays. The selected reference voltage V... ref Applied to the selected precision resistor R std Above, a traceable theoretical value of I is generated. std = V ref / R std The standard microcurrent.

[0011] Optionally, in the S2 gold channel establishment step, for each range, at least two standard microcurrents with different values ​​are used for linear calibration to achieve high-precision calibration under multiple ranges.

[0012] Here, linear calibration is performed using two standard current points, 100pA and 1nA, in the 100pA-1nA range; linear calibration is performed using two standard current points, 1nA and 10nA, in the 1nA-10nA range; linear calibration is performed using two standard current points, 10nA and 100nA, in the 10nA-100nA range, and so on, to achieve fast and high-precision calibration across multiple ranges.

[0013] Optionally, in the S3 multi-channel fast matching step, the formula for calculating the consistency ratio coefficient is: K i =V g / V i K i V is the consistency ratio coefficient. g V represents the response of the gold channel to the reference microcurrent. i Let be the response value of the i-th test channel to the same reference microcurrent.

[0014] Optionally, in the S1 hardware zero-point adjustment step, the zero-adjustment component is a digital potentiometer. The digital potentiometer is connected to the zero-adjustment circuit of each channel's transimpedance amplifier. Fine zeroing of each channel is achieved by adjusting the digital potentiometer and its voltage divider resistor and capacitor filter circuit.

[0015] Secondly, a fast matching system for the gain consistency of multi-channel weak current testing, used to perform the fast matching method for the gain consistency of multi-channel weak current testing described above, includes: a programmable precision current source for outputting a standard microcurrent and a reference microcurrent.

[0016] The multiplexed switch matrix has its input connected to the programmable precision current source and multiple outputs connected to the input of each test channel, which is used to switch the application of microcurrent to each test channel.

[0017] Multiple test channels, each test channel including at least a channel input switch, a transimpedance amplifier, an I / V conversion amplifier switch, a gain amplifier, a signal filter, and an analog-to-digital converter.

[0018] The control and processing unit is communicatively connected to the programmable precision current source, digital potentiometer, multiplexer matrix, computer, and functional components of each test channel, and is used to control the coordinated operation of each component.

[0019] Optionally, the programmable precision current source includes a high-precision programmable reference voltage source, a precision resistor array controlled by a current range switching relay, and a switch drive circuit.

[0020] Optionally, the rapid matching system for gain consistency of multi-channel weak current testing also includes a data storage device, which is communicatively connected to the control processing unit and used to store and read gain parameters, consistency ratio coefficients and test data during the calibration process in real time.

[0021] Optionally, the rapid matching system for gain consistency of multi-channel weak current testing also includes a temperature sensor, which is communicatively connected to the control processing unit to monitor the test environment temperature in order to achieve system temperature drift compensation.

[0022] Optionally, the computer is equipped with an operation interface and control program for the entire test and calibration process and system control.

[0023] Compared with existing technologies, the rapid matching method and system for gain consistency of multi-channel weak current testing provided by this invention has the following significant advantages: achieving a balance between accuracy and consistency: through the golden channel establishment step, the system measurement is traced back to the theoretical standard value, ensuring measurement accuracy; through the multi-channel rapid matching step, all channels are aligned with the golden channel, greatly improving multi-channel consistency and solving the problem of difficulty in balancing accuracy and consistency in existing technologies.

[0024] Improved calibration efficiency: High-precision traceability calibration is limited to a single golden channel, while the remaining channels are calibrated through simple and quick proportional coefficient matching. This avoids the cumbersome process of performing independent high-precision calibration for each channel, reducing the calibration time of the entire system from the traditional hours to minutes, and significantly improving the instrument production efficiency and factory quality.

[0025] The system is highly robust: it uses the real-time response of the gold channel as a benchmark for multi-channel matching, which can automatically compensate for system common-mode drift caused by factors such as changes in ambient temperature and power fluctuations; combined with the temperature drift compensation function of the temperature sensor, it further improves the long-term stability and anti-interference capability of the system.

[0026] High cost-effectiveness: Through system design optimization and intelligent algorithms, the stringent requirements for the absolute accuracy of each channel component are reduced. High-order measurement performance can be achieved without the use of high-cost precision components, effectively controlling the instrument production cost and improving the product's cost-effectiveness. Attached Figure Description

[0027] Figure 1 A simplified flowchart illustrating the rapid matching method for gain consistency in multi-channel weak current testing provided in this embodiment of the invention.

[0028] Figure 2 This is a flowchart illustrating a rapid matching method for gain consistency in multi-channel weak current testing provided in an embodiment of the present invention.

[0029] Figure 3 This is a block diagram illustrating the leakage current testing principle of a rapid matching system for gain consistency in multi-channel weak current testing, as described in an embodiment of this invention.

[0030] Figure 4 This is a block diagram illustrating the control principle of a fast matching system for gain consistency in multi-channel weak current testing, as described in an embodiment of this invention.

[0031] Figure 5 This is a histogram comparison of the results of multi-channel testing of components from the same batch before calibration.

[0032] Figure 6 This is a histogram comparison of the results of multi-channel testing of components from the same batch after calibration. Detailed Implementation

[0033] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0034] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0035] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.

[0036] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0037] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0038] It should be noted that the "multi-channel" in the multi-channel weak current test gain consistency fast matching method and system described in this application refers to the number of channels N, which is theoretically applicable to hardware systems with fewer than 32 channels. To reduce transmission errors, it is particularly suitable for 4 to 8-channel test systems. To more clearly and accurately describe the embodiments of the present invention, the appendix... Figure 3 The leakage current test principle block diagram only lists 113a: the golden channel (test channel 1), 113b: test channel 2, and 113h: test channel 8. Test channels 3 to 7 are omitted and will not be described again.

[0039] It should be understood that the "rapid matching method for gain consistency in multi-channel weak current testing" provided in this application embodiment is executed by a corresponding "rapid matching system for gain consistency in multi-channel weak current testing". The matching method embodies the control logic and processing flow of the embodiments of this application, and the matching system embodies the physical implementation method. Together, they constitute a complete technical solution.

[0040] See Figure 1 and Figure 2 Firstly, the typical implementation process of the rapid matching method for gain consistency of multi-channel weak current testing provided in the embodiments of this application is as follows: S1: Hardware zero-point adjustment: control each test channel 113 and its corresponding test fixture path, and adjust the zero-adjustment component connected to the transimpedance amplifier 109 of each channel respectively in the open circuit state of the test fixture electrode so that the output response value of each channel falls into the preset zero-point target range.

[0041] S2: Establishment of the Golden Channel: At at least one range setting, at least two standard micro-currents of different values ​​are applied to the selected test channel 113 through the programmable precision current source 120 integrated within the system. Based on the response of the test channel 113 to the at least two standard micro-currents, the channel gain parameters are accurately calculated to minimize the error between the output response and the theoretical value, thus establishing the golden channel as the absolute accuracy benchmark of the system.

[0042] S3: Multi-channel fast matching: At at least one range setting, control the programmable precision current source 120 to output a fixed reference micro-current, and apply the reference micro-current simultaneously or sequentially to all test channels 113, including the gold channel, through the multiplexed switch matrix 106. Based on the response value of the gold channel, calculate and store the consistency ratio coefficient of the remaining channels.

[0043] S4: Measurement Data Correction Application: During actual measurement, the consistency ratio coefficient corresponding to each channel is called to correct the original test data of the channel in real time and output the measurement result after consistency correction.

[0044] Specifically, in step S201, the computer 122 sends a system start calibration command to the control processing unit (MCU) 121, and the system begins fully automatic calibration.

[0045] In step S202, while ensuring the test fixture electrodes are open-circuited, the control processing unit 121 controls the channel input switching switches K111, K112, and K118 to connect all test channels 113 to their corresponding test fixtures. The leakage current of the device under test is input to each test channel 113 from each leakage current input port 100 (100a: leakage current input port 1 (CHN1), 100b: leakage current input port 2 (CHN2), 100h: leakage current input port 8 (CHN8)). Subsequently, the output value of each channel's analog-to-digital converter (ADC) 112 is read sequentially or in parallel, and adjustment commands are sent to the corresponding channel's digital potentiometers 104 (channel 1 digital potentiometer 104a, channel 2 digital potentiometer 104b, channel 8 digital potentiometer 104h) through a closed-loop control algorithm until the output value of each output channel stabilizes within the preset zero-point offset threshold range. After zero-point adjustment is completed, all channel input switching switches K111, K112, and K118 are disconnected.

[0046] Preferably, before zero-point calibration, all transimpedance amplifiers 109 of all channels (channel 1 transimpedance amplifier 109a, channel 2 transimpedance amplifier 109b, and channel 8 transimpedance amplifier 109h) are switched to K10 controlled by channel 1 I / V conversion amplifier switching switch 108a, K20 controlled by channel 2 I / V conversion amplifier switching switch 108b, and K80 controlled by channel 8 I / V conversion amplifier switching switch 108h, so as to select the weakest test current range for zero-point calibration.

[0047] Preferably, for the 16-bit analog-to-digital converter used in this embodiment, the preset threshold for zero-point adjustment deviation is ±5 ADC conversion values, so as to ensure that the absolute deviation of the system is controlled within 0.03%.

[0048] In step S203, the current range switching relay 102 and the multiplexer matrix 106 are controlled to switch to the target range.

[0049] Preferably, the range is switched to K1 controlled by the current range switching relay 102 to select the weakest test current range for calibration.

[0050] Preferably, the calibration channel is switched to SW101 controlled by the multiplexer switch matrix 106, and channel 1 is selected as the reference gold calibration channel.

[0051] Then we move on to Phase One: Golden Channel Traceability and Calibration.

[0052] To more clearly demonstrate the execution process of the embodiments of the present invention, the following will use 1nA to 10nA ranges as examples for a clear description.

[0053] It should be noted that the resistor included in 103 is R. std1 For 1000MΩ, R std2 For 100MΩ, R std3 For 10MΩ, R std4 1MΩ, R std5 For 100KΩ, R std6 It is 10KΩ.

[0054] Step S204: Control the programmable voltage source 101 to output the reference voltage V. ref =1V, the reference voltage V ref R applied to the precision resistor array 103 std1 This yields the reference current I. std1 =1V / 1000MΩ=1nA.

[0055] Step S205: Control the reference voltage loading switch SWB and SW101 of the multiplexing switch matrix 106 to apply the standard current I. std1 The signal is sent to channel 1, and the channel response output voltage value V is collected. meas1 .

[0056] Step S206: Control the programmable voltage source 101 to output the reference voltage V. ref =1V, the reference voltage V ref R applied to the precision resistor array 103 std2 This yields the reference current I. std2 =1V / 100MΩ=10nA.

[0057] Step S207: Control the reference voltage loading switch SWB and SW101 of the multiplexing switch matrix 106 to apply the standard current I. std2The signal is sent to channel 1, and the channel response output voltage value V is collected. meas2 .

[0058] Preferably, to ensure the accuracy of traceability calibration, steps S204 to S207 can be repeated cyclically, and then I is obtained through averaging. std1 V meas1 I std2 V meas2 .

[0059] Step S208, the control processing unit 121 according to (I std1 V meas1 ) and (I std2 V meas2 Using these two sets of data, the precise gain K of channel 1 at the current gear level is calculated using the formula V=K·I+B. G1 and zero offset B offset1 The data is then stored in data storage 123. At this point, channel 1 has been traced and calibrated in this position.

[0060] It should be noted that, theoretically, precise zeroing was already performed before the source calibration of channel 1. Therefore, the zero-point offset B after the source calibration of channel 1 is... offset1 The accuracy should be sufficient to guarantee the value near zero, when the deviation is within ±5 ADC conversion values, and can be ignored.

[0061] Then we move on to Phase Two: Multi-channel rapid matching.

[0062] Step S209, the programmable precision current source 120 outputs a fixed reference current (such as I). std =5nA).

[0063] In step S210, under the control of the control processing unit 121, the multiplexer switch matrix 106 transfers the current (I) std =5nA) Access channel 1, which is also the gold traceability channel, and collect the response value V of channel 1. g .

[0064] Step S211, the control processing unit 121 controls the multiplexing switch matrix 106 to transfer the current (I) std =5nA) Connect the matching channel to be calibrated. For example, connect channel 2, i.e. 113b, by switching SW102 of the multiplexing switch matrix 106, and collect the response value V2 of the channel.

[0065] In step S212, the control processing unit 121 calibrates and matches all test channels using a polling method. When one channel is calibrated and matched, it automatically proceeds to step S213, where the calibration channel switches to the next matching channel, and step S211 is repeated. When all channels are calibrated and matched, the control processing unit 121 removes the applied reference current and disconnects all multiplexed switch matrices 106. At this point, the calibration data acquisition for all channels in this range has been completed.

[0066] Step S214: After the calibration data for one gear is collected, the control processing unit 121 uses the response value V of the gold channel. g Based on this, calculate the consistency scaling factor K for each channel i. i The calculation formula is: K i =V g / V i Among them, V i This is the calibration matching response value for the i-th channel.

[0067] Step S215, when the consistency ratio coefficient K of a gear is... i Once the calculation is complete, the control processing unit 121 automatically switches the calibration process to the next level of data calibration and matching, repeating the calibration steps from S203 to S214. This continues until data calibration for all channels and all levels is complete.

[0068] Step S216: Save the calibration data for all channels and all test settings to the non-volatile data storage 123. At this point, multi-channel data matching is complete.

[0069] Entering Phase Three, the calibration and application phase.

[0070] Step S217: After completing the multi-channel data calibration process, the test circuit can be put into actual testing applications. Whenever the analog-to-digital converter 112 of one channel acquires the raw data V... i At that time, the control processing unit 121 will perform correction calculations: I leak =K i ·V i / RF.

[0071] Where I leak K represents the leakage current value measured in the current test channel i. i RF represents the consistency scaling factor for the current test channel, and RF represents the I / V conversion amplification resistor of the current transimpedance amplifier 109.

[0072] This yields the accurate leakage current value measured in measurement channel i.

[0073] See Figure 3 and Figure 4Secondly, embodiments of this application provide a fast matching system for the gain consistency of multi-channel weak current testing. The control principle block diagram of the matching system includes: a programmable precision current source 120, a multiplexed switch matrix 106, multiple test channels 113, a control processing unit 121, a computer 122, a data storage device 123, and a temperature sensor 124.

[0074] Furthermore, the programmable precision current source 120 includes a high-precision programmable precision voltage source 101 and a precision resistor array 103 controlled by a current range switching relay 102. By changing the reference voltage applied to different precision resistors, the output current I is controlled. std Programming.

[0075] Furthermore, the multiplexed switch matrix 106 has its input connected to the output of the programmable precision current source 120, and its multiple outputs connected to the inputs of multiple test channels 113. Under the control of the control processing unit 121, it can switch the current signal to a designated channel.

[0076] Furthermore, there are multiple test channels 113, including the first test channel 113a, which is the gold reference channel for system gain calibration, the second test channel 113b, and the eighth test channel 113h. For the sake of simplicity, the third to seventh test channels are omitted here and will not be described again. Each test channel includes at least the following: a transimpedance amplifier 109 (channel 1 transimpedance amplifier 109a, channel 2 transimpedance amplifier 109b, channel 8 transimpedance amplifier 109h), a gain amplifier 110 (channel 1 gain amplifier 110a, channel 2 gain amplifier 110b, channel 8 gain amplifier 110h), a signal filter 111 (channel 1 signal filter 111a, channel 2 signal filter 111b, channel 8 signal filter 111h), an analog-to-digital converter 112 (channel 1 analog-to-digital converter 112a, channel 2 analog-to-digital converter 112b, channel 8 analog-to-digital converter 112h), an I / V conversion resistor and filter capacitor 107 (channel 1 I / V conversion resistor and filter capacitor 107a, channel 2 I / V conversion resistor and filter capacitor 107b, channel 8 I / V conversion resistor and filter capacitor 107h), and a channel I / V conversion amplifier switching switch 108 (channel 1 I / V conversion amplifier switching switch 108a, channel 2 ... I / V conversion amplifier switching switch 108b and channel 8 I / V conversion amplifier switching switch 108h). The above components, under the control of the control processing unit 121, realize the functions of current to voltage signal conversion, amplification, filtering and data acquisition.

[0077] Furthermore, multiple test channels 113, each of which also includes a digital potentiometer 104 (channel 1 digital potentiometer 104a, channel 2 digital potentiometer 104b, channel 8 digital potentiometer 104h), are used to connect to the voltage divider zeroing circuits 105 (channel 1 voltage divider zeroing circuit 105a, channel 2 voltage divider zeroing circuit 105b, channel 8 voltage divider zeroing circuit 105h) of the transimpedance amplifiers 109 (channel 1 transimpedance amplifier 109a, channel 2 transimpedance amplifier 109b, channel 8 transimpedance amplifier 109h) of each channel. In the traceability calibration step, the fine zeroing function of the gold channel and other matching channels is achieved by adjusting the digital potentiometer 104 and its voltage divider resistor and capacitor filter circuit.

[0078] Furthermore, the control processing unit 121 is communicatively connected to the programmable precision current source 120, the multiplexed switch matrix 106, multiple test channels 113, the computer 122, the data storage device 123, and the temperature sensor 124. This enables it to perform the following functional steps in system gain consistency calibration: hardware zero-point adjustment, golden channel establishment, multi-channel rapid matching, and measurement data correction.

[0079] Furthermore, the control processing unit 121 also needs to maintain communication with the computer 122, the data storage device 123, and the temperature sensor 124. The computer 122 has an operation interface and control program for the entire test calibration process and control. The data storage device 123 is used to store and read the gain parameters, consistency ratio coefficients, and test data during the calibration process in real time. The temperature sensor 124 is used to monitor the test environment temperature to achieve system temperature drift compensation.

[0080] Figure 5 and Figure 6 The technical effects before and after implementing this invention are visually demonstrated: whereby Figure 5 Before matching the system calibration, the distribution histogram of test results for each channel was obtained. The mean value was AVE=0.387. The channel with the largest mean deviation was 7 (G-LINE), with a mean value of 0.400 and a mean deviation of 3.36%. Figure 6 To match the distribution histogram of test results for each channel after system calibration, the mean value is AVE=0.396. The data distribution of all channels is highly concentrated, and the mean values ​​are close to consistent. The channels with the largest mean deviations, channels 2 (B-LINE) and 8 (H-LINE), have mean deviations of about 0.5%, which proves the excellent ability of the embodiments of this invention to improve consistency.

[0081] As can be seen from the above working principle, the rapid matching method and system for gain consistency in multi-channel weak current testing disclosed in this invention includes the following matching methods: a traceability calibration stage, where a designated channel is finely calibrated using a multi-range precision current source 120 integrated internally to establish a golden channel as the accuracy benchmark; a rapid matching stage, where a stable reference current is injected into all test channels through a high-speed polling process via a switch matrix, and the consistency ratio coefficient of the remaining channels is calculated based on the response value of the golden channel; and a calibration application stage, where the original data of each channel is multiplied by its specific ratio coefficient during actual testing to output a high-consistency result after calibration. The matching system includes hardware and control programs for executing the above methods. This invention achieves a balance between accuracy and multi-channel consistency, with a fully automatic and rapid calibration process, reducing the overall system calibration time from hours to minutes, greatly improving instrument production efficiency and factory quality.

[0082] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0083] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A rapid matching method for gain consistency in multi-channel weak current testing, characterized in that, Includes the following steps: S1: Hardware zero-point adjustment: Control each test channel and its corresponding test fixture path. With the test fixture electrodes open, adjust the zero-adjustment components connected to the transimpedance amplifier of each channel to make the output response value of each channel fall into the preset zero-point target range. S2: Establishment of the Golden Channel: At least two standard micro-currents of different values ​​are applied to the selected test channel through the programmable precision current source integrated in the system at at least one range setting. Based on the response of the test channel to the at least two standard micro-currents, the channel gain parameters are accurately calculated to minimize the error between the output response and the theoretical value, and the golden channel is established as the absolute accuracy benchmark of the system. S3: Multi-channel fast matching: At at least one range setting, the programmable precision current source is controlled to output a fixed reference micro-current. This reference micro-current is applied simultaneously or sequentially to all test channels, including the gold channel, through a multiplexed switch matrix. Based on the response value of the gold channel, the consistency ratio coefficient of the remaining channels is calculated and stored. The formula for calculating the consistency ratio coefficient is: Ki=Vg / Vi, where Ki is the consistency ratio coefficient, Vg is the response value of the gold channel to the reference micro-current, and Vi is the response value of the i-th test channel to the same reference micro-current. S4: Measurement Data Correction Application: During actual measurement, the consistency ratio coefficient corresponding to each channel is called to correct the original test data of the channel in real time and output the measurement result after consistency correction.

2. The rapid matching method for gain consistency in multi-channel weak current testing according to claim 1, characterized in that, In the S2 gold channel establishment step, the programmable precision current source consists of a programmable reference voltage source and a resistor array with a precise calibrated resistance value that is switched by a relay. By applying the selected reference voltage Vref to the selected precision resistor Rstd, a traceable standard microcurrent with a theoretical value of Istd = Vref / Rstd is generated.

3. The rapid matching method for gain consistency in multi-channel weak current testing according to claim 1, characterized in that, In the S2 gold channel establishment step, for each range, at least two standard microcurrents with different values ​​are used for linear calibration to achieve high-precision calibration under multiple ranges.

4. The rapid matching method for gain consistency in multi-channel weak current testing according to claim 1, characterized in that, In the S1 hardware zero-point adjustment step, the zero-adjustment component is a digital potentiometer. The digital potentiometer is connected to the zero-adjustment circuit of each channel's transimpedance amplifier. Fine zeroing of each channel is achieved by adjusting the digital potentiometer and its voltage divider resistors and capacitor filter circuits.

5. A rapid matching system for gain consistency in multi-channel weak current testing, used to execute the rapid matching method for gain consistency in multi-channel weak current testing as described in any one of claims 1-4, characterized in that, The rapid matching system for gain consistency in multi-channel weak current testing includes: Programmable precision current source for outputting standard microcurrent and reference microcurrent; A multiplexed switch matrix, with its input connected to the programmable precision current source and multiple outputs connected to the input of each test channel, is used to switch and apply microcurrents to each test channel. Multiple test channels, each test channel including at least a channel input switch, a transimpedance amplifier, an I / V conversion amplifier switch, a gain amplifier, a signal filter, and an analog-to-digital converter; The control and processing unit is communicatively connected to the programmable precision current source, digital potentiometer, multiplexer matrix, computer, and functional components of each test channel, and is used to control the coordinated operation of each component.

6. The rapid matching system for gain consistency in multi-channel weak current testing according to claim 5, characterized in that, The programmable precision current source includes a high-precision programmable reference voltage source, a precision resistor array controlled by a current range switching relay, and a switch drive circuit.

7. The rapid matching system for gain consistency in multi-channel weak current testing according to claim 5, characterized in that, It also includes a data storage device, which is communicatively connected to the control processing unit and is used to store and read gain parameters, consistency ratio coefficients and test data during the calibration process in real time.

8. The rapid matching system for gain consistency in multi-channel weak current testing according to claim 5, characterized in that, It also includes a temperature sensor, which is communicatively connected to the control processing unit to monitor the test environment temperature in order to achieve system temperature drift compensation.

9. The rapid matching system for gain consistency in multi-channel weak current testing according to claim 5, characterized in that, The computer is equipped with an operating interface and control program for the entire testing and calibration process and system control.

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