A full-automatic test system for current sensor based on ATE and programmable current source

Abstract

The application discloses a kind of current sensor full-automatic test system based on ATE and programmable current source, including ATE master control platform, programmable current source module, test interface adaptation unit, signal acquisition and conditioning module, multichannel data acquisition module, closed loop feedback calibration module and automatic sorting output module;The ATE master control platform is respectively with programmable current source module, multichannel data acquisition module.The application is controlled programmable current source module, test interface adaptation unit, multichannel data acquisition module and automatic sorting output module by ATE master control platform concentration, constructs from loading, automatic docking, parameter test, result determination to the complete automation test link of automatic sorting, without manual intervention, effectively overcome the technical defects of low efficiency of traditional manual test mode, and the batch production test efficiency is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of automated chip testing technology, specifically to a fully automated testing system for current sensors based on ATE and a programmable current source. Background Technology

[0002] As is well known, current sensors are indispensable core measurement components in fields such as power systems, industrial automation, new energy power generation, and electric vehicles. The reliability of their performance directly affects the safe and stable operation of the entire system. Therefore, before a current sensor is put into practical application, its various performance indicators must be comprehensively and rigorously tested to verify key parameters such as accuracy, linearity, temperature stability, and dynamic response characteristics.

[0003] Currently, current sensor testing faces several key technical challenges: First, low testing efficiency and insufficient automation. Traditional current sensor testing often relies on manual operation, requiring testers to manually connect test circuits, adjust current source output, record test data, and interpret results one by one. This method is not only time-consuming and labor-intensive but also prone to human error, making it unsuitable for large-scale production testing. While some automated test equipment (ATE) has been applied to electronic component testing, existing ATE systems are mostly designed for functional testing of semiconductor devices or circuit boards, lacking specialized solutions for current sensor characteristic testing. Second, insufficient accuracy and stability of the excitation current source. The testing accuracy of a current sensor directly depends on the accuracy of the excitation current source. Existing testing equipment often employs an open-loop control structure. Under load, the actual output current deviates from the set value due to factors such as component temperature drift and circuit impedance changes, and there is a lack of effective real-time calibration mechanisms. This loss of accuracy directly affects the accuracy of test results and may lead to misjudgments of current sensor performance. Third, incomplete test item coverage and a lack of systematic testing procedures. Performance evaluation of current sensors needs to cover multiple dimensions, including static parameters (such as zero-point offset, linearity, and accuracy) and dynamic parameters (such as frequency response, step response, and rise time). However, existing testing schemes often only test a single or a few parameters, failing to provide a comprehensive performance evaluation of current sensors. Fourth, the data acquisition and processing capabilities are limited. Existing testing systems suffer from problems such as a small number of channels, low sampling rates, and poor synchronization in data acquisition, making it difficult to accurately capture the output characteristics of current sensors under transient conditions. Furthermore, the lack of intelligent data analysis and judgment capabilities makes it difficult to guarantee the reliability of test results. Fifth, there is a lack of automated sorting and classification mechanisms. In mass production testing scenarios, current sensors need to be classified according to the test results after testing (e.g., qualified products, unqualified products, different accuracy levels, etc.). Existing systems mostly rely on manual sorting, which is inefficient and prone to errors.

[0004] Therefore, there is an urgent need for a fully automated current sensor testing system that integrates a high-precision programmable current source, multi-channel synchronous data acquisition, closed-loop real-time calibration, and automatic sorting functions to solve the problems of low testing efficiency, insufficient accuracy, incomplete coverage, and lack of automatic sorting in the existing technologies. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems of low testing efficiency, insufficient accuracy, incomplete coverage and lack of automatic sorting in existing testing systems, and to provide a fully automatic testing system for current sensors based on ATE and programmable current source.

[0006] To achieve the above objectives, the present invention employs the following technical solution: a fully automated current sensor testing system based on an ATE (Automatic Test Equipment) and a programmable current source, comprising an ATE main control platform, a programmable current source module, a test interface adapter unit, a signal acquisition and conditioning module, a multi-channel data acquisition module, a closed-loop feedback calibration module, and an automatic sorting output module; the ATE main control platform is connected to the programmable current source module, the multi-channel data acquisition module, the closed-loop feedback calibration module, and the automatic sorting output module respectively; the output terminal of the programmable current source module is connected to the current input terminal of the test interface adapter unit via a high-current power cable; the signal output terminal of the test interface adapter unit is connected to the input terminal of the signal acquisition and conditioning module via an analog signal transmission line; the output terminal of the signal acquisition and conditioning module is connected to the input terminal of the multi-channel data acquisition module via an analog signal transmission line; the current sampling input terminal of the closed-loop feedback calibration module is connected in series in the main output loop between the programmable current source module and the test interface adapter unit, and its data output terminal is connected to the feedback signal input terminal of the ATE main control platform.

[0007] Furthermore, the ATE main control platform includes a microprocessor, which has a real-time operating system embedded inside;

[0008] The test sequence management unit, which is connected to the microprocessor via an internal memory bus, is used to store and manage test sequences of various current sensors;

[0009] The communication interface unit connects to the microprocessor via the PCIe bus and interacts with external devices or a host computer via Ethernet, USB, or RS-485 communication interfaces.

[0010] The human-machine interface unit is connected to the communication interface unit via the LVDS display bus and is used for parameter setting, test monitoring and status display.

[0011] The programmable current source module includes: a multi-level precision current source array, which is connected to the microprocessor via a parallel control bus;

[0012] The current range switching matrix has its control signal input terminal connected to the ATE main control platform via the GPIO control bus, its current input terminal connected to the output terminals of each range of the multi-range precision current source array, and its common output terminal connected to the current input terminal of the test interface adapter unit via a high-current power cable.

[0013] The current output protection unit has its current input terminal connected in series with the common output terminal of the current range switching matrix, and its current output terminal connected to the test interface adapter unit through a high-current power cable.

[0014] The multi-level precision current source array is configured as follows: In the first mode, it outputs a constant DC current for static parameter testing of the current sensor under test, including zero-point offset, linearity, and accuracy; in the second mode, it outputs a sinusoidal AC current with programmable frequency and amplitude for frequency response testing of the current sensor under test; in the third mode, it outputs a pulse current waveform with programmable rising and falling edges for dynamic response characteristic testing of the current sensor under test; and in the fourth mode, it outputs a composite current waveform superimposed with harmonic components for anti-interference capability testing of the current sensor under test under non-ideal power grid conditions.

[0015] The test interface adapter unit includes: a general test fixture, whose electrical input terminal is connected to the output terminal of the programmable current source module through a high-current power cable, and whose electrical output terminal is connected to the signal output terminal of the current sensor under test through a signal detection cable, for fixing the current sensor under test and providing electrical connection;

[0016] The interface adapter circuit board has its input terminal connected to the detection signal output terminal of the general test fixture via a ribbon cable, and its output terminal connected to the signal acquisition and conditioning module via an analog signal transmission line.

[0017] The automatic docking device has its drive control signal input end connected to the ATE main control platform via an industrial control bus, and its mechanical actuator end connected to the moving part of the universal test fixture. Under the control of the ATE main control platform, it realizes the automatic electrical docking and disconnection of the current sensor under test and the test system.

[0018] The signal acquisition and conditioning module includes: a preamplifier unit, whose input end is connected to the signal output end of the test interface adapter unit through an analog signal transmission line, and whose output end is connected to the input end of the filter unit through an analog signal transmission line, for preamplifying the weak induced signal output by the current sensor under test;

[0019] The filter unit has its input end connected to the output end of the preamplifier unit, and its output end connected to the input end of the programmable gain amplifier unit (403) through an analog signal transmission line, for filtering out high-frequency noise and power frequency interference in the signal;

[0020] The programmable gain amplifier unit has its control signal input terminal connected to the ATE main control platform via an SPI bus, its signal input terminal connected to the output terminal of the filter unit, and its signal output terminal connected to the input terminal of the multi-channel data acquisition module via an analog signal transmission line. Under the control of the ATE main control platform, the amplification factor is automatically adjusted according to the signal amplitude.

[0021] The multi-channel data acquisition module includes: a synchronous sampling analog-to-digital converter array, whose analog signal input terminal is connected to the signal output terminal of the signal acquisition and conditioning module, whose synchronous clock input terminal is connected to the clock output terminal of the ATE main control platform through a synchronous clock cable, and whose digital signal output terminal is connected to the input terminal of the high-speed data buffer unit through a parallel data bus;

[0022] The high-speed data buffer unit has its input end connected to the digital signal output end of the synchronous sampling analog-to-digital converter array, and its output end connected to the input end of the data transmission interface through a high-speed serial communication bus, for temporary storage of sampled data;

[0023] The data transmission interface has its input end connected to the output end of the high-speed data buffer unit, and its output end connected to the data input end of the ATE main control platform through a high-speed serial communication bus, so that the sampled data can be transmitted to the ATE main control platform in real time through the high-speed serial bus.

[0024] The closed-loop feedback calibration module includes: a high-precision current sampling unit, whose current input terminal is connected in series to the main output circuit between the programmable current source module and the test interface adapter unit, and whose signal output terminal is connected to the analog input terminal of the feedback analog-to-digital converter through an analog signal transmission line, for real-time measurement of the actual output excitation current value;

[0025] A precision voltage reference source, whose voltage output terminal is connected to the reference voltage input terminal of the feedback analog-to-digital converter via an analog signal line, is used to provide a highly stable reference for the high-precision current sampling unit.

[0026] The feedback analog-to-digital converter has its analog signal input terminal connected to the signal output terminal of the high-precision current sampling unit, and its digital signal output terminal connected to the feedback signal input terminal of the ATE main control platform via a high-speed SPI bus. It is used to convert the sampled current signal into a digital quantity and send it to the ATE main control platform.

[0027] The ATE main control platform has a built-in digital PID controller, which adjusts the output amplitude register value of the DDS chip of the programmable current source module or the input code value of the digital-to-analog converter in real time according to the deviation between the sampled value and the set value of the feedback analog-to-digital converter.

[0028] The automatic sorting output module includes: a test result analysis unit, whose data input terminal is connected to the test result output terminal of the ATE main control platform through an internal data bus, and whose control signal output terminal is connected to the sorting execution mechanism and the marking unit through an industrial control bus, respectively, for analyzing and classifying the collected test data according to a preset judgment threshold;

[0029] The sorting actuator has its drive signal input end connected to the control signal output end of the test result analysis unit, and its mechanical transmission end connected to the inlet of multiple sorting bins, including multiple sorting bins and an automatic transfer device, used to transfer the current sensor to be tested to the corresponding sorting bin according to the judgment result.

[0030] The marking unit has its control signal input terminal connected to the control signal output terminal of the test result analysis unit, and its execution terminal is located above the classification path of the sorting execution mechanism, for physically or electronically marking the current sensors that are determined to be unqualified.

[0031] As a preferred embodiment, the system also includes: a temperature environment control module, whose control signal input terminal is connected to the ATE main control platform via an industrial control bus, and is set around the test station of the test interface adapter unit, for controlling the temperature of the test environment during the test to support temperature drift testing and performance evaluation under different temperature conditions;

[0032] The temperature environment control module includes a temperature sensor, a heating unit, and a cooling unit. The temperature sensor is installed close to the test station, and the heating unit and cooling unit are arranged around the test station. Under the control of the ATE main control platform, the test environment temperature is stabilized at the set temperature point.

[0033] Compared with the prior art, the beneficial effects of the present invention are:

[0034] (1) This invention centrally controls the programmable current source module, test interface adapter unit, multi-channel data acquisition module and automatic sorting output module through the ATE main control platform, and constructs a complete automated test link from material loading, automatic docking, parameter testing, result judgment to automatic sorting. No manual intervention is required, which effectively overcomes the technical defects of low efficiency in traditional manual testing methods and greatly improves the efficiency of mass production testing.

[0035] (2) The present invention connects the high-precision current sampling unit of the closed-loop feedback calibration module in series to the main output circuit of the programmable current source module, measures the actual output excitation current value in real time and feeds it back to the ATE main control platform. The output parameters are dynamically adjusted by the built-in digital PID controller, and the current deviation caused by factors such as line impedance change and power device temperature drift is automatically compensated, ensuring that the excitation current can be stabilized at the set value with high precision under all working conditions, thereby improving the accuracy and reliability of the test results.

[0036] (3) The programmable current source module of the present invention supports four output modes: constant DC, programmable sinusoidal AC, pulse current waveform and composite current waveform with superimposed harmonic components. With the help of a variety of built-in test sequences and temperature environment control modules, a single device can complete multi-dimensional tests such as static parameters, frequency response, dynamic response, anti-interference ability and temperature drift, overcoming the technical limitations of traditional test schemes that are single in items and incomplete in coverage.

[0037] (4) In the multi-channel data acquisition module of the present invention, each analog-to-digital converter channel works uniformly under the global synchronous clock, ensuring strict synchronous sampling of the output signals of each channel sensor, effectively avoiding phase measurement errors caused by inconsistent sampling times of each channel, providing a high-fidelity data foundation for frequency response testing and dynamic response testing, and significantly improving the accuracy of dynamic testing. Attached Figure Description

[0038] Figure 1 This is a block diagram of the overall structure of the system of the present invention.

[0039] Figure 2 This is a schematic diagram of the ATE master control platform of the present invention.

[0040] Figure 3 This is a schematic diagram of the programmable current source module of the present invention.

[0041] Figure 4 This is a schematic diagram of the test interface adapter unit of the present invention.

[0042] Figure 5 This is a schematic diagram of the signal acquisition and conditioning module of the present invention.

[0043] Figure 6 This is a schematic diagram of the structure of the multi-channel data acquisition module of the present invention.

[0044] Figure 7 This is a schematic diagram of the closed-loop feedback calibration module of the present invention.

[0045] Figure 8 This is a schematic diagram of the automatic sorting output module of the present invention. Detailed Implementation

[0046] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] Example

[0048] like Figure 1 As shown, this embodiment provides a fully automated testing system for current sensors based on ATE and a programmable current source. The system includes an ATE main control platform 100, a programmable current source module 200, a test interface adapter unit 300, a signal acquisition and conditioning module 400, a multi-channel data acquisition module 500, a closed-loop feedback calibration module 600, an automatic sorting output module 700, and a temperature environment control module 900.

[0049] The current sensor 800 under test is the product to be tested in this embodiment, and it is independent of the system described in this embodiment.

[0050] The ATE main control platform 100 is the core control unit of this invention. It is connected to the programmable current source module 200, the multi-channel data acquisition module 500, the closed-loop feedback calibration module 600, the automatic sorting output module 700, and the temperature environment control module 900, forming a star control architecture centered on the ATE main control platform 100. The specific connection relationships are as follows:

[0051] The programmable current source module 200 is bidirectionally connected to the ATE main control platform 100 via a high-speed parallel control bus, used to receive control commands and return status information; the current input terminal of the test interface adapter unit 300 is connected to the output terminal of the programmable current source module 200 via a high-current power cable, used to receive excitation current; the signal output terminal of the test interface adapter unit 300 is connected to the input terminal of the signal acquisition and conditioning module 400 via an analog signal transmission line, used to transmit the induced signal of the current sensor under test 800 to the subsequent processing stage; the output terminal of the signal acquisition and conditioning module 400 is connected to the input terminal of the multi-channel data acquisition module 500 via an analog signal transmission line; the multi-channel data acquisition module 500 is connected to the ATE main control platform 100 via a high-speed serial communication bus. The TE main control platform 100 is bidirectionally connected to transmit digitized sampling data to the ATE main control platform 100. The current sampling input terminal of the closed-loop feedback calibration module 600 is connected in series to the main output circuit between the programmable current source module 200 and the test interface adapter unit 300. Its data output terminal is connected to the ATE main control platform 100 via a high-speed SPI bus to feed back the real-time sampled actual current value to the ATE main control platform 100. The automatic sorting output module 700 is connected to the ATE main control platform 100 via an industrial fieldbus to receive sorting commands. The temperature environment control module 900 is connected to the ATE main control platform 100 via an industrial control bus and is located around the test station of the test interface adapter unit 300.

[0052] The structure of the ATE main control platform 100 is as follows: Figure 2 As shown, the ATE main control platform 100 includes a microprocessor 102, a test sequence management unit 101, a communication interface unit 103, and a human-machine interaction unit 104.

[0053] The microprocessor 102 employs a high-performance ARM Cortex-A series processor, with an embedded real-time operating system, serving as the core of the entire testing system's computation and control. The test sequence management unit 101 is connected to the microprocessor 102 via an internal memory bus, used to store and manage various current sensor test sequences, including linearity test sequences, zero-point drift test sequences, temperature drift test sequences, frequency response test sequences, and dynamic response test sequences. The communication interface unit 103 is connected to the microprocessor 102 via a PCIe bus and interacts with external devices or a host computer via Ethernet, USB, or RS-485 communication interfaces. The human-machine interface unit 104 is connected to the communication interface unit 103 via an LVDS display bus. This human-machine interface unit 104 includes at least a touchscreen display and function buttons for parameter setting, test monitoring, and status display.

[0054] like Figure 3As shown, the programmable current source module 200 includes a multi-level precision current source array 201, a current level switching matrix 202, and a current output protection unit 203.

[0055] The multi-level precision current source array 201 is connected to the microprocessor 102 via a parallel control bus. Its core employs an architecture where a DDS chip and a high-precision DAC work in tandem, enabling it to generate high-precision excitation current signals under the control of the microprocessor 102. The control signal input terminal of the current level switching matrix 202 is connected to the ATE main control platform 100 via a GPIO control bus. Its current input terminal is connected to the output terminals of each level of the multi-level precision current source array 201, and its common output terminal is connected to the current input terminal of the test interface adapter unit 300 via a high-current power cable, enabling automatic switching of current levels, covering a range from microamperes to kiloamperes. The current input terminal of the current output protection unit 203 is connected in series with the common output terminal of the current level switching matrix 202, and its current output terminal is connected to the test interface adapter unit 300 via a high-current power cable.

[0056] In this embodiment, the current output protection unit 203 includes an overcurrent protection circuit and an overheat protection circuit, which are used to cut off the output of the corresponding channel when the output is abnormal, so as to ensure system safety.

[0057] The multi-level precision current source array 201 has the following four modes, specifically configured as follows:

[0058] In the first mode, a constant DC current is output for testing the static parameters of the current sensor under test, including zero offset, linearity, and accuracy.

[0059] In the second mode, a sinusoidal alternating current with programmable frequency and amplitude is output for frequency response testing of the current sensor under test.

[0060] In the third mode, a pulse current waveform with programmable rising and falling edges is output for testing the dynamic response characteristics of the current sensor under test.

[0061] In the fourth mode, a composite current waveform with superimposed harmonic components is output, which is used to test the anti-interference capability of the current sensor under test under non-ideal power grid conditions.

[0062] The structure of the test interface adapter unit 300 is as follows: Figure 4 As shown, it includes a general-purpose test fixture 301, an interface adapter circuit board 302, and an automatic docking device 303.

[0063] The electrical input terminal of the general-purpose test fixture 301 is connected to the output terminal of the current output protection unit 203 of the programmable current source module 200 via a high-current power cable to receive the excitation current; its signal output terminal is connected to the signal output terminal of the current sensor under test 800 via a signal detection cable to acquire the sensing signal of the current sensor under test 800.

[0064] The universal test fixture 301 is used to fix the current sensor 800 under test and provide a standardized electrical connection. The input terminal of the interface adapter circuit board 302 is connected to the detection signal output terminal of the universal test fixture 301 via a ribbon cable, and its output terminal is connected to the signal acquisition and conditioning module 400 via an analog signal transmission line.

[0065] The general-purpose test fixture 301 contains standardized interface circuitry for different types of current sensors.

[0066] The drive control signal input terminal of the automatic docking device 303 is connected to the ATE main control platform 100 through the industrial control bus, and its mechanical actuator is connected to the moving part of the general test fixture 301. Under the control of the ATE main control platform 100, the automatic electrical docking and disconnection of the current sensor 800 under test and the test system is realized without the need for manual wiring.

[0067] The structure of the signal acquisition and conditioning module 400 is as follows: Figure 5 As shown, it includes a preamplifier unit 401, a filter unit 402, and a programmable gain amplifier unit 403.

[0068] The input terminal of the preamplifier unit 401 is connected to the output terminal of the interface adapter circuit board 302 of the test interface adapter unit 300 via an analog signal transmission line, and its output terminal is connected to the input terminal of the filter unit 402 via an analog signal transmission line, which is used to preamplify the weak induced signal output by the current sensor 800 under test.

[0069] The input terminal of the filter unit 402 is connected to the output terminal of the preamplifier unit 401, and its output terminal is connected to the input terminal of the programmable gain amplifier unit 403 through an analog signal transmission line, which is used to filter out high-frequency noise and power frequency interference in the signal.

[0070] The control signal input terminal of the programmable gain amplifier unit 403 is connected to the ATE main control platform 100 via the SPI bus. Its signal input terminal is connected to the output terminal of the filter unit 402, and its signal output terminal is connected to the input terminal of the multi-channel data acquisition module 500 via the analog signal transmission line. Under the control of the ATE main control platform 100, the amplification factor is automatically adjusted according to the signal amplitude to ensure that the analog-to-digital converter can work in the optimal quantization range under different signal amplitudes.

[0071] The structure of the multi-channel data acquisition module 500 is as follows: Figure 6 As shown, it includes a synchronous sampling analog-to-digital converter array 501, a high-speed data buffer unit 502, and a data transmission interface 503.

[0072] The analog signal input terminal of the synchronous sampling analog-to-digital converter array 501 is connected to the signal output terminal of the signal acquisition and conditioning module 400. Its synchronous clock input terminal is connected to the clock output terminal of the ATE main control platform 100 through a synchronous clock cable. Its digital signal output terminal is connected to the input terminal of the high-speed data buffer unit 502 through a parallel data bus.

[0073] The synchronous sampling analog-to-digital converter array 501 contains multiple high-resolution analog-to-digital converter channels, all of which are synchronously sampled under the global synchronous clock provided by the ATE master control platform 100.

[0074] This embodiment employs a synchronous sampling mechanism to ensure that the sampling of the sensor output signals from each channel by the multi-channel data acquisition module 500 is strictly consistent along the time axis, with no deviation in sampling timing. This allows for an accurate reflection of the true phase relationship between the output signals. This is particularly important for frequency response and dynamic response testing, avoiding phase measurement errors introduced by inconsistent sampling times across channels.

[0075] The input of the high-speed data buffer unit 502 is connected to the digital signal output of the synchronous sampling analog-to-digital converter array 501, and its output is connected to the input of the data transmission interface 503 through a high-speed serial communication bus, which is used to temporarily store sampled data to prevent data loss.

[0076] The output of the data transmission interface 503 is connected to the data input of the ATE main control platform 100 via a high-speed serial communication bus, transmitting the sampled data to the ATE main control platform 100 in real time for analysis and processing.

[0077] The structure of the closed-loop feedback calibration module 600 is as follows: Figure 7 As shown, it includes a high-precision current sampling unit 601, a precision voltage reference source 602, and a feedback analog-to-digital converter 603.

[0078] Specifically, the current input terminal of the high-precision current sampling unit 601 is connected in series to the main output circuit between the programmable current source module 200 and the test interface adapter unit 300, so that all the excitation current flowing through the current sensor under test 800 flows through the high-precision current sampling unit 601, thereby ensuring that the sampled current value truly reflects the excitation current actually applied to the current sensor under test 800.

[0079] The signal output terminal of the high-precision current sampling unit 601 is connected to the analog input terminal of the feedback analog-to-digital converter 603 via an analog signal transmission line. The digital signal output terminal of the feedback analog-to-digital converter 603 is connected to the feedback signal input terminal of the ATE main control platform 100 via a high-speed SPI bus.

[0080] The voltage output terminal of the precision voltage reference source 602 is connected to the reference voltage input terminal of the feedback analog-to-digital converter 603 through an analog signal line, providing a highly stable reference for the high-precision current sampling unit 601 and ensuring sampling accuracy.

[0081] Based on the above connection relationship, the closed-loop feedback calibration working principle of this embodiment is as follows: The high-precision current sampling unit 601 measures the actual excitation current in the main circuit in real time, converts it into a digital quantity through the feedback analog-to-digital converter 603, and then sends it to the microprocessor 102 of the ATE main control platform 100 via the high-speed SPI bus. The microprocessor 102 has a built-in digital PID controller, which compares the actual current value with the target value set by the user, calculates the deviation value, and then dynamically generates a compensation amount to adjust the output amplitude register value of the DDS chip in the programmable current source module 200 or the input code value of the digital-to-analog converter in real time.

[0082] The closed-loop regulation process described above iterates multiple times within each power frequency cycle, automatically compensating for current deviations caused by factors such as changes in line impedance, temperature drift of power devices, and load fluctuations, ensuring that the actual output excitation current can be stabilized at the set value with high precision under all operating conditions.

[0083] The structure of the automatic sorting output module 700 is as follows: Figure 8 As shown, it includes a test result analysis unit 701, a sorting execution mechanism 702, and a marking unit 703.

[0084] The data input terminal of the test result analysis unit 701 is connected to the test result output terminal of the ATE main control platform 100 through an internal data bus. Its control signal output terminal is connected to the sorting actuator 702 and the marking unit 703 through an industrial control bus, respectively, and is used to analyze and determine the level of the collected test data according to the preset judgment threshold.

[0085] The drive signal input terminal of the sorting actuator 702 is connected to the control signal output terminal of the test result analysis unit 701, and its mechanical transmission terminal is connected to the inlet of multiple sorting bins. In this embodiment, the sorting actuator 702 includes multiple sorting bins and an automatic transfer device, used to transfer the current sensor 800 to be tested to the corresponding sorting bin according to the judgment result.

[0086] The control signal input terminal of the marking unit 703 is connected to the control signal output terminal of the test result analysis unit 701, and its execution terminal is set above the sorting path of the sorting execution mechanism 702, for physically or electronically marking the current sensors that are determined to be unqualified.

[0087] As a preferred embodiment, the system may also include a temperature environment control module 900, whose control signal input terminal is connected to the ATE main control platform 100 via an industrial control bus. Its execution terminals (including a temperature sensor, a heating unit, and a cooling unit) are positioned around the test station of the test interface adapter unit 300. The temperature sensor is installed close to the test station, while the heating and cooling units are arranged around the test station.

[0088] Under the control of the ATE main control platform 100, the temperature environment control module 900 stabilizes the test environment temperature at the set temperature point (usually in the range of -40℃ to +85℃) to support temperature drift testing and performance evaluation under different temperature conditions.

[0089] Based on the above system, this embodiment takes the testing of a Hall effect current sensor as an example to illustrate the complete workflow of the system in this embodiment:

[0090] Step 1: Loading and Docking. The operator places the current sensor 800 under test in the designated position on the universal test fixture 301 and starts the test through the human-machine interface unit 104. The ATE main control platform 100 issues control commands, and the automatic docking device 303 drives the moving parts of the universal test fixture 301 to achieve automatic electrical docking between the current sensor 800 under test and the test system.

[0091] Step 2: Test Parameter Configuration. The operator selects "Linearity Test Sequence" through the human-machine interface unit 104, setting the current test range (e.g., 0A to 1000A), the number of test points (e.g., 11 points), and the accuracy judgment threshold (e.g., ±0.5%). The test sequence management unit 101 of the ATE main control platform 100 loads the corresponding test sequence and parses it into specific control parameters.

[0092] Step 3: Excitation Current Output and Closed-Loop Regulation. The ATE main control platform 100 sends a control command containing current range and amplitude information to the programmable current source module 200. The multi-range precision current source array 201 generates the corresponding excitation current signal according to the set value. After passing through the current range switching matrix 202 and the current output protection unit 203, it is output to the general test fixture 301 through a high-current power cable and applied to the current sensor 800 under test.

[0093] While the excitation current is output, the closed-loop feedback calibration module 600, connected in series in the main output circuit, operates in real time: the high-precision current sampling unit 601 measures the actual current value in the main circuit in real time, converts it into a digital value via the feedback analog-to-digital converter 603, and transmits it to the ATE main control platform 100 via the high-speed SPI bus. The built-in digital PID controller of the microprocessor 102 compares the actual current value with the set value, calculates the deviation value, and dynamically adjusts the output amplitude register value of the DDS chip in the multi-level precision current source array 201. This process iterates multiple times in each power frequency cycle to ensure that the actual output current is stabilized at the set value with high precision.

[0094] Step 4: Signal Acquisition and Processing. The current sensor 800 outputs an induced signal based on the excitation current. This signal is then amplified by the preamplifier unit 401, filtered to remove noise by the filter unit 402, and automatically adjusted for gain by the programmable gain amplifier unit 403 according to the signal amplitude before being sent to the multi-channel data acquisition module 500.

[0095] All channels in the synchronous sampling analog-to-digital converter array 501 are synchronously sampled under the global synchronous clock provided by the ATE main control platform 100, and the analog signals are synchronously converted into digital signals. After being temporarily stored in the high-speed data buffer unit 502, they are transmitted to the ATE main control platform 100 in real time through the data transmission interface 503.

[0096] Step 5: Result Judgment and Sorting. After completing all test points, the ATE main control platform 100 calculates parameters such as linearity and accuracy of the current sensor based on the collected data. The test result analysis unit 701 determines the grade according to the preset judgment threshold, the sorting execution mechanism 702 transfers the current sensor to the corresponding classification bin according to the judgment result, and the marking unit 703 automatically marks the unqualified products.

[0097] Step Six: Temperature Drift Test. This step is optional. If a temperature drift test is required, the ATE main control platform 100 sends a temperature setting command to the temperature environment control module 900. The temperature environment control module 900 stabilizes the test environment temperature at the target temperature point (e.g., -40℃, +25℃, +85℃). Steps Three to Five are repeated to complete the performance test under different temperature conditions.

[0098] As described above, the present invention can be well implemented.

Claims

1. A fully automated testing system for current sensors based on ATE and a programmable current source, characterized in that, The system includes an ATE main control platform (100), a programmable current source module (200), a test interface adapter unit (300), a signal acquisition and conditioning module (400), a multi-channel data acquisition module (500), a closed-loop feedback calibration module (600), and an automatic sorting output module (700). The ATE main control platform (100) is connected to the programmable current source module (200), the multi-channel data acquisition module (500), the closed-loop feedback calibration module (600), and the automatic sorting output module (700). The output terminal of the programmable current source module (200) is connected to the test interface adapter unit (300). The current input terminal is connected via a high-current power cable; the signal output terminal of the test interface adapter unit (300) is connected to the input terminal of the signal acquisition and conditioning module (400) via an analog signal transmission line; the output terminal of the signal acquisition and conditioning module (400) is connected to the input terminal of the multi-channel data acquisition module (500) via an analog signal transmission line; the current sampling input terminal of the closed-loop feedback calibration module (600) is connected in series in the main output loop between the programmable current source module (200) and the test interface adapter unit (300), and its data output terminal is connected to the feedback signal input terminal of the ATE main control platform (100).

2. The fully automated testing system for current sensors based on ATE and a programmable current source according to claim 1, characterized in that, The ATE master control platform (100) includes: The microprocessor (102) has a real-time operating system embedded inside it; The test sequence management unit (101) is connected to the microprocessor (102) via an internal memory bus and is used to store and manage various current sensor test sequences; The communication interface unit (103) is connected to the microprocessor (102) via the PCIe bus and interacts with external devices or host computers via Ethernet, USB or RS-485 communication interfaces. The human-machine interaction unit (104) is connected to the communication interface unit (103) via the LVDS display bus and is used for parameter setting, test monitoring and status display.

3. The fully automated testing system for current sensors based on ATE and a programmable current source according to claim 2, characterized in that, The programmable current source module (200) includes: A multi-stage precision current source array (201) is connected to a microprocessor (102) via a parallel control bus; The current level switching matrix (202) has its control signal input terminal connected to the ATE main control platform (100) via the GPIO control bus, its current input terminal connected to the output terminals of each level of the multi-level precision current source array (201), and its common output terminal connected to the current input terminal of the test interface adapter unit (300) via a high current power cable. The current output protection unit (203) has its current input terminal connected in series with the common output terminal of the current range switching matrix (202), and its current output terminal is connected to the test interface adapter unit (300) through a high current power cable.

4. The fully automated testing system for current sensors based on ATE and a programmable current source according to claim 3, characterized in that, The configuration of the multi-stage precision current source array (201) is as follows: In the first mode, a constant DC current is output for testing the static parameters of the current sensor under test, including zero offset, linearity, and accuracy. In the second mode, a sinusoidal alternating current with programmable frequency and amplitude is output for frequency response testing of the current sensor under test. In the third mode, a pulse current waveform with programmable rising and falling edges is output for testing the dynamic response characteristics of the current sensor under test. In the fourth mode, a composite current waveform with superimposed harmonic components is output, which is used to test the anti-interference capability of the current sensor under test under non-ideal power grid conditions.

5. The fully automated testing system for current sensors based on ATE and a programmable current source according to claim 4, characterized in that, The test interface adaptation unit (300) includes: The general-purpose test fixture (301) has its electrical input terminal connected to the output terminal of the current output protection unit (203) of the programmable current source module (200) via a high-current power cable; The interface adapter circuit board (302) has its input end connected to the detection signal output end of the general test fixture (301) via a ribbon cable, and its output end connected to the signal acquisition and conditioning module (400) via an analog signal transmission line. The automatic docking device (303) has its drive control signal input end connected to the ATE main control platform (100) via an industrial control bus, and its mechanical execution end connected to the moving part of the general test fixture (301). Under the control of the ATE main control platform (100), it realizes the automatic electrical docking and separation of the current sensor under test and the test system.

6. The fully automated testing system for current sensors based on ATE and a programmable current source according to claim 1, characterized in that, The signal acquisition and conditioning module (400) includes: The input terminal of the preamplifier unit (401) is connected to the signal output terminal of the test interface adapter unit (300) through an analog signal transmission line, and its output terminal is connected to the input terminal of the filter unit (402) through an analog signal transmission line. It is used to preamplify the weak induced signal output by the current sensor under test. The filter unit (402) has its input end connected to the output end of the preamplifier unit (401), and its output end connected to the input end of the programmable gain amplifier unit (403) through an analog signal transmission line, and is used to filter out high-frequency noise and power frequency interference in the signal; The programmable gain amplifier unit (403) has its control signal input terminal connected to the ATE main control platform (100) via the SPI bus, its signal input terminal connected to the output terminal of the filter unit (402), and its signal output terminal connected to the input terminal of the multi-channel data acquisition module (500) via the analog signal transmission line. Under the control of the ATE main control platform (100), the amplification factor is automatically adjusted according to the signal amplitude.

7. The fully automated testing system for current sensors based on ATE and a programmable current source according to claim 6, characterized in that, The multi-channel data acquisition module (500) includes: The synchronous sampling analog-to-digital converter array (501) has its analog signal input terminal connected to the signal output terminal of the signal acquisition and conditioning module (400), its synchronous clock input terminal connected to the clock output terminal of the ATE main control platform (100) through a synchronous clock cable, and its digital signal output terminal connected to the input terminal of the high-speed data buffer unit (502) through a parallel data bus. A high-speed data buffer unit (502) has its input end connected to the digital signal output end of the synchronous sampling analog-to-digital converter array (501), and its output end connected to the input end of the data transmission interface (503) via a high-speed serial communication bus, for temporarily storing sampled data; The data transmission interface (503) has its input end connected to the output end of the high-speed data buffer unit (502), and its output end is connected to the data input end of the ATE main control platform (100) through a high-speed serial communication bus. The sampled data is transmitted to the ATE main control platform (100) in real time through the high-speed serial bus.

8. The fully automated testing system for current sensors based on ATE and a programmable current source according to claim 7, characterized in that, The closed-loop feedback calibration module (600) includes: The high-precision current sampling unit (601) has its current input terminal connected in series in the main output circuit between the programmable current source module (200) and the test interface adapter unit (300), and its signal output terminal is connected to the analog input terminal of the feedback analog-to-digital converter (603) through the analog signal transmission line, for real-time measurement of the actual output excitation current value; A precision voltage reference source (602) has its voltage output terminal connected to the reference voltage input terminal of the feedback analog-to-digital converter (603) via an analog signal line, and is used to provide a highly stable reference for the high-precision current sampling unit (601); The feedback analog-to-digital converter (603) has its analog signal input terminal connected to the signal output terminal of the high-precision current sampling unit (601), and its digital signal output terminal connected to the feedback signal input terminal of the ATE main control platform (100) via a high-speed SPI bus. It is used to convert the sampled current signal into a digital quantity and send it to the ATE main control platform (100). The ATE main control platform (100) has a built-in digital PID controller that adjusts the output amplitude register value of the DDS chip of the programmable current source module (200) or the input code value of the digital-to-analog converter in real time according to the deviation between the sampled value and the set value of the feedback analog-to-digital converter (603).

9. The fully automated testing system for current sensors based on ATE and a programmable current source according to claim 8, characterized in that, The automatic sorting output module (700) includes: The test result analysis unit (701) has its data input terminal connected to the test result output terminal of the ATE main control platform (100) via an internal data bus, and its control signal output terminal connected to the sorting actuator (702) and the marking unit (703) via an industrial control bus, respectively, for analyzing and classifying the collected test data according to a preset judgment threshold. The sorting actuator (702) has its drive signal input end connected to the control signal output end of the test result analysis unit (701), and its mechanical transmission end connected to the inlet of multiple sorting bins, including multiple sorting bins and an automatic transfer device, which is used to transfer the current sensor to be tested to the corresponding sorting bin according to the judgment result. The marking unit (703) has its control signal input terminal connected to the control signal output terminal of the test result analysis unit (701), and its execution terminal is located above the classification path of the sorting execution mechanism (702) for physically or electronically marking the current sensors that are determined to be unqualified.

10. The fully automated testing system for current sensors based on ATE and a programmable current source according to claim 1, characterized in that, The system also includes a temperature environment control module (900), whose control signal input terminal is connected to the ATE main control platform (100) via an industrial control bus and is set around the test station of the test interface adapter unit (300) to control the temperature of the test environment during the test to support temperature drift test and performance evaluation under different temperature conditions. The temperature environment control module (900) includes a temperature sensor, a heating unit and a cooling unit. The temperature sensor is installed close to the test station, and the heating unit and cooling unit are arranged around the test station. Under the control of the ATE main control platform (100), the test environment temperature is stabilized at the set temperature point.

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