MCU-based multi-station parallel automatic test system and method

Abstract

The invention discloses an MCU-based multi-station parallel automatic test system and method, and belongs to the technical field of semiconductor discrete device environment test. The system comprises a core control unit used for executing system initialization, channel selection control, test data processing and working mode switching; the channel isolation control unit comprises a plurality of paths of independent optocoupler isolation circuits; the man-machine interaction unit comprises a key input module and a state display module; the test execution unit comprises a path switching module and a parameter tester; the parameter tester is used for carrying out electrical performance parameter detection on the tested product accessed into the loop; the data interaction unit comprises a communication module and upper computer software; the upper computer software is used for receiving, storing and processing test data; according to the invention, the test efficiency of 80 devices can be improved within one minute, and the batch test requirement is met; the tested device does not need to be taken out from the high-low temperature test box, frosting and data deviation caused by manual operation are avoided, and the test result is more stable and accurate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of environmental test of semiconductor discrete devices, in particular to a multi-station parallel automatic test system and method based on MCU. BACKGROUND

[0002] In the production and quality inspection process of TVS transient voltage suppression diode semiconductor discrete devices, product performance testing and high-low temperature environmental testing are key processes to verify the stability of device performance. The existing traditional testing method has the following core defects: 1. Low testing efficiency: the traditional scheme can only test one device at a time, and the actual testing efficiency is less than 3 per minute, which cannot meet the batch testing demand; 2. Human intervention causes precision deviation: the device needs to be taken out of the high-low temperature test box during testing, and the detection needs to be completed within 8 seconds, which relies on manual operation throughout. Especially in the low-temperature test scenario, manual taking and placing can easily cause frost on the surface of the device, directly affecting the accuracy of the test data; 3. Poor data consistency: the randomness of manual operation (such as taking and placing speed, test timing difference) leads to large differences in test data of different devices, and cannot form stable and reliable test results. To solve the above problems, an automatic testing scheme is needed to improve testing efficiency and data accuracy without taking out the device under test, supporting batch parallel testing, and reducing human error. Therefore, we propose a multi-station parallel automatic test system and method based on MCU. SUMMARY

[0003] The purpose of the present application is to provide a multi-station parallel automatic test system and method based on MCU to solve the technical problems of low efficiency, easy frosting, and large data difference in traditional high-low temperature environmental testing of semiconductor discrete devices.

[0004] To achieve the above purpose, the present application provides the following technical scheme: A multi-station parallel automatic test system based on MCU, including a core control unit, using a microcontroller (MCU) to perform system initialization, channel selection control, test data processing, and working mode switching; A channel isolation control unit containing multiple independent optocoupler isolation circuits for realizing electrical isolation between the test loop and the control circuit and rapid switching of the test channel; A human-computer interaction unit including a key input module and a state display module; the key input module is used for test channel selection and test mode setting; the state display module is used for real-time display of the test state of each channel; The test execution unit comprises a channel switching module and a parameter tester; the channel switching module is used for connecting the selected channel of the product under test to the test loop according to the instruction of the core control unit; and the parameter tester is used for detecting the electrical performance parameters of the product under test connected to the loop. The data interaction unit comprises a communication module and host computer software; the communication module is used for realizing the data communication between the core control unit and the parameter tester and the host computer software; and the host computer software is used for receiving, storing and processing the test data.

[0005] Preferably, the channel isolation control unit comprises 80 optical coupling isolation circuits, each of which is integrated with a high-speed optical coupling with a response time ≤ 2 μs.

[0006] Preferably, in the human-computer interaction unit, the key input module comprises keys for channel increment / decrement selection, a manual test key and an automatic test key. The state display module is an LED liquid crystal screen, which identifies the pass or abnormal state of the channel test through different color indicator lights.

[0007] Preferably, the product under test is a semiconductor discrete device.

[0008] Preferably, the microcontroller used by the core control unit is an STM32F103ZET6 model, which is configured with an 8MHz crystal oscillator as a clock reference.

[0009] Preferably, the communication module of the data interaction unit is a serial communication module with a baud rate of 9600 bps, which is used for bidirectional data transmission between the core control unit, the parameter tester and the host computer software.

[0010] The MCU multi-station parallel automatic test method based on the above system comprises the following steps: S1, power on and initialization of the system, and then enter the standby state; S2, the user selects the target test channel and the test mode through the human-computer interaction unit; the test mode includes a single manual test mode for the selected channel and a sequential automatic cycle test mode for all channels; S3, according to the selected mode, the core control unit controls the channel isolation control unit and the channel switching module in the test execution unit to build a complete test channel comprising the product under test and the parameter tester, and triggers the parameter tester to detect; S4, after the parameter tester completes the detection, the data is fed back to the core control unit and the host computer software through the data interaction unit; the core control unit analyzes the data and determines the result, and controls the state display module to update the indication state of the corresponding channel at the same time; S5, the test process is ended, and the system returns to the standby state.

[0011] Preferably, in the automatic cycle test mode of step S3, the core control unit activates all channels in a preset order one by one, and performs data acquisition and feedback after the test of each channel is completed, until all channels are tested.

[0012] Preferably, the electrical performance parameters detected by the parameter tester include the on-voltage and the reverse leakage current.

[0013] Preferably, in step S3, in the automatic cycle test mode, each channel is tested for 100 ms before the next channel test is started, avoiding module action conflicts; during the test, it supports interruption at any time and performs a reset operation, and after the reset, the system returns to the initialized standby state, and the test channel automatically jumps to the initial channel.

[0014] Compared with the prior art, the beneficial effects of the present application are: 1. Efficiency is greatly improved: 80 devices can be tested in 1 minute, which is more than 50 times higher than the traditional scheme (<3 / min), meeting the batch testing demand. 2. Higher test accuracy: The tested device does not need to be taken out of the high-low temperature test box, avoiding frost and data deviation caused by manual operation, and the test result is more stable and accurate. 3. Flexible and reliable operation: supports manual single-point debugging (convenient for troubleshooting) and automatic batch testing (convenient for mass production and quality inspection); industrial-grade MCU and voltage stabilizing circuit are used to ensure the stability of long-time continuous operation.

[0015] Data traceability: PC software realizes data storage and report generation, which is convenient for subsequent quality traceability and data analysis. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a whole working principle diagram of a multi-station parallel environmental test test system; Figure 2 is a TLP185 optocoupler isolation relay control circuit structure diagram; Figure 3 is a four-key input circuit structure diagram; Figure 4 is a system control flow diagram. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all.

[0018] Embodiment: Please refer to Figures 1-4 A multi-station parallel automatic test system based on MCU, comprising: The core control unit adopts a microcontroller (MCU) for performing system initialization, channel selection control, test data processing and working mode switching; the microcontroller adopted is an STM32F103ZET6 model, and the microcontroller is configured with an 8MHz crystal oscillator as a clock reference.

[0019] The channel isolation control unit contains multiple independent optocoupler isolation circuits for realizing electrical isolation between the test loop and the control circuit and rapid switching of the test channels; the channel isolation control unit contains 80 optocoupler isolation circuits (each containing a TLP185 optocoupler), each circuit integrates a high-speed optocoupler with a response time ≤2μs; the optocoupler isolation technology is adopted to realize electrical isolation of the "control circuit-test loop", to avoid interference, and at the same time, a relay matrix is adopted to realize flexible switching of 80 channels, supporting single-channel or multi-channel parallel testing.

[0020] The human-computer interaction unit includes a key input module and a state display module; the key input module is used for test channel selection and test mode setting; the state display module is used for real-time display of the test state of each channel; the key input module includes keys for channel increment / decrement selection, a manual test key and an automatic test key; the state display module is an LED liquid crystal screen, which identifies the pass or abnormal state of channel testing through different color indicator lights.

[0021] For example, the human-computer interaction unit includes a four-key input module (TS-1101-C-W type key) and an LED liquid crystal display unit; the key input module contains channel increment / decrement keys, a manual test key and an automatic test key, which are used for channel selection and mode setting; the LED liquid crystal display unit displays the test state of each channel (green / red indicator light) in real time, realizing "operation-feedback" visualization.

[0022] The test execution unit includes a path switching module (i.e. a test end relay control module) and a parameter tester (an SD-HDT-600 diode tester can be selected); the path switching module is used for connecting the selected channel of the measured product to the test loop according to the instruction of the core control unit; the parameter tester is used for detecting the electrical performance parameters of the measured product connected to the loop.

[0023] For example, the test execution unit is composed of a test end relay control module and an SD-HDT-600 diode tester; the relay control module is responsible for connecting / disconnecting the test path, and the SD-HDT-600 diode tester is used for accurately detecting the on-voltage and reverse leakage current of the device.

[0024] Data interaction unit, including communication module (serial communication module) and host computer software (PC test software); the communication module is used for realizing data communication between the core control unit and the parameter tester and the host computer software; the host computer software is used for receiving, storing and processing test data. The communication module of the data interaction unit is a serial communication module, and the baud rate thereof is 9600bps, which is used for realizing bidirectional data transmission of the core control unit, the parameter tester and the host computer software.

[0025] For example, the serial communication module (realizing bidirectional data transmission of MCU and tester, MCU and PC) and PC test software; the test software supports real-time data display, historical storage, report generation, which is convenient for data tracing and analysis.

[0026] The product to be tested in the application is a semiconductor discrete device, specifically a TVS transient voltage suppression diode, and the test interface adapts to the connection requirements of the semiconductor discrete device.

[0027] It also includes a power supply unit: an external power supply and an internal voltage stabilizing circuit, which provides stable working voltage for the whole system after being processed by the internal voltage stabilizing circuit after being connected to the external power supply. The system follows the closed-loop control logic of "initialization → mode selection → channel control → test execution → data feedback → end / reset".

[0028] 1. Hardware implementation details 1.1 Core control unit The STM32F103ZET6 minimum system circuit is adopted, including power management, reset circuit and 8MHz external crystal oscillator; the GPIO pin of the MCU is connected to the control end of the optocoupler isolation circuit, the signal end of the four-key input module and the driving end of the LED liquid crystal display unit; the USART serial port pin is connected to the SD-HDT-600 tester and the PC end, realizing data transmission. 1.2 Optocoupler isolation circuit The circuit structure of each channel is as shown in Figure 2 (TLP185 optocoupler isolation relay control circuit): TLP185GB-S type optocoupler is adopted, cooperating with MMBT3904LT1G (NPN triode), G5NB-1A-E-DC5V type relay and 1N589S type diode (freewheeling protection); the input end of the optocoupler is connected to the GPIO pin of the MCU, and the output end controls the on-off of the relay; R17 (470Ω) and R18 (10kΩ) in the circuit are current limiting resistors, which guarantee the safety of the device; the circuit structure of 80 channels is completely consistent, and the channel switching is realized through the relay matrix. 1.3 Four-key input circuit The circuit is as shown in Figure 3The (key circuit) shown: using 4 TS-1101-C-W type light touch key (SW2-SW5 respectively corresponding to the increase key, decrease key, manual test key, automatic test key); one end of each key is grounded, and the other end is connected to the GPIO pin of the MCU through a pull-up resistor (3.3V power supply); when the key is pressed, the pin level changes from high to low, and the MCU recognizes the key command by detecting the level change. 1.4 Power supply unit External 12V DC power supply, 5V voltage output through LM1117-5V voltage regulator chip, and 3.3V voltage output through AMS1117-3.3V voltage regulator chip; 5V voltage is used for power supply of relay, optocoupler and other modules, and 3.3V voltage is used for power supply of MCU, key module and the like, to ensure that the voltages of various modules match. 2. Software implementation details The control program is written in C language based on Keil MDK development environment, mainly including the following function modules: Initialization module: configure the GPIO (input / output mode) of the MCU, USART serial port (baud rate 9600bps), timer (used for key debouncing); initialize the LED display interface (default display "standby-channel 1"); Key processing module: use timer debouncing (10ms delay) to identify key type (increase / decrease / manual / automatic) and update current channel number or test mode; Channel control module: according to the current channel number, output high and low level to control the relay on-off of the corresponding optocoupler isolation circuit, and control the test end relay to connect the tester; Data acquisition and processing module: receive test data (such as forward voltage drop value, reverse leakage current value) sent by the SD-HDT-600 tester through the serial port, compare with the preset threshold, and judge the test result (normal / abnormal); Display and upload module: control the LED liquid crystal display unit to update the current channel state (green / red); send test data (channel number, parameter value, result) to PC test software through serial port; Automatic test module: in automatic mode, activate channels 1-80 in turn through loop statement, delay 100ms after completing one channel test (to avoid module conflict), and send "test end" command after completing all tests.

[0029] The MCU multi-station parallel automatic test method based on the above system includes the following steps: S1, system power-on and initialization, then enter standby state.

[0030] Specifically, 1.1, the external power supply is connected, and after being processed by the internal voltage stabilizing circuit, it supplies power to each unit of the system; 1.2, 8MHz crystal oscillator, provides clock reference for STM32F103ZET6 microcontroller; 1.3, STM32F103ZET6 microcontroller completes system initialization, including: configuration of each peripheral module (key, LED liquid crystal display unit, 80-channel optocoupler isolation circuit, test end relay control module), initialization of serial communication interface, reset of 80-channel optocoupler isolation circuit and test end relay control module; 1.4, after initialization, the system enters standby state, waiting for user operation.

[0031] S2, the user selects the target test channel and test mode through the man-machine interaction unit; the test mode includes single manual test mode for the selected channel and sequential automatic cycle test mode for all channels.

[0032] Specifically, 2.1, the user operates through the four-key input module: selects the target test channel by switching between channels 1-80 through the "increase" or "decrease" keys. 2.2, if the "manual test key" is pressed, the system starts the single-channel test process; if the "automatic test key" is pressed, the system starts the 80-channel sequential cycle test process.

[0033] S3, according to the selected mode, the core control unit controls the channel isolation control unit and the path switching module in the test execution unit, constructs a complete test path containing the product under test and the parameter tester, and triggers the parameter tester to detect; in the automatic cycle test mode, the core control unit activates all channels in a predetermined sequence, and performs data acquisition and feedback after the test of each channel is completed, until all channels are tested. In the automatic cycle test mode, each channel test is completed after a delay of 100ms before starting the next channel test, to avoid module action conflict; during the test process, it supports interrupting at any time and performing reset operation, after reset, the system returns to the standby state after initialization, and the test channel automatically jumps to the initial channel.

[0034] Specifically, 3.1, channel control and test triggering: the STM32F103ZET6 microcontroller drives the corresponding number of optocoupler isolation circuits according to the selected channel, connects the product under test of the channel to the test loop; the microcontroller controls the test end relay control module to connect the SD-HDT-600 diode tester to the test loop, forming a complete test path; triggers the SD-HDT-600 diode tester to detect the electrical performance parameters of the product under test of the current channel.

[0035] 3.2, Automatic test flow: STM32F103ZET6 microcontroller activates the opto-isolator circuit of each channel in sequence from channel 1 to channel 80; repeat the "test + data feedback" operation for each channel, complete after 100ms delay.

[0036] 3.3, Reset operation: the test process can be interrupted at any time, and the system returns to the initialized standby state after executing the reset operation, and the channel jumps to "channel 1".

[0037] S4, After the parameter tester completes the detection, the data is fed back to the core control unit and the upper computer software through the data interaction unit; the core control unit analyzes the data and determines the result, and controls the state display module to update the corresponding channel indication state.

[0038] Specifically, test data acquisition and feedback: 4.1, after the SD-HDT-600 diode tester completes the detection, the test data is sent to the STM32F103ZET6 microcontroller through the serial communication module.

[0039] 4.2, the microcontroller receives and analyzes the test data, and judges the test result of the measured product (normal / abnormal).

[0040] 4.3, the microcontroller controls the LED liquid crystal display unit according to the judgment result, and displays green (normal) or red (abnormal) state light corresponding to the channel; at the same time, the test data is uploaded to the PC terminal test software through the serial communication module, realizing data storage, real-time display and report generation. 4.4, the manual test flow ends, and the system returns to the standby state.

[0041] S5, the test flow ends, and the system returns to the standby state.

[0042] Specifically, 5.1, the manual test flow ends, and the system returns to the standby state; 5.2, after the automatic test flow (80 channels are completed) ends, the system prompts that the test is completed, and returns to the standby state.

[0043] In this application, the electrical performance parameters detected by the parameter tester include the forward voltage and the reverse leakage current.

[0044] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above examples, and the above examples and descriptions in the specification are only preferred examples of the present application, and are not intended to limit the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A multi-station parallel automated testing system based on an MCU, characterized in that, include: The core control unit, which uses a microcontroller (MCU), is used to perform system initialization, channel selection control, test data processing, and working mode switching. The channel isolation control unit contains multiple independent optocoupler isolation circuits to achieve electrical isolation between the test circuit and the control circuit, as well as rapid switching of the test channel; The human-computer interaction unit includes a button input module and a status display module; the button input module is used for test channel selection and test mode setting; the status display module is used to display the test status of each channel in real time. The test execution unit includes a path switching module and a parameter tester; the path switching module is used to connect the product under test to the test circuit of the selected channel according to the instructions of the core control unit; the parameter tester is used to test the electrical performance parameters of the product under test connected to the circuit. The data interaction unit includes a communication module and host computer software; the communication module is used to realize data communication between the core control unit, the parameter tester, and the host computer software; the host computer software is used to receive, store, and process test data.

2. The MCU-based multi-station parallel automated testing system according to claim 1, characterized in that: The channel isolation control unit contains 80 optical coupler isolation circuits, each circuit integrating a high-speed optical coupler with a response time ≤2μs.

3. The MCU-based multi-station parallel automated testing system according to claim 1, characterized in that: In the human-computer interaction unit, the button input module includes buttons for channel increment / decrement selection, manual test buttons, and automatic test buttons; The status display module is an LED LCD screen, which uses different colored indicator lights to indicate whether the channel test has passed or is in an abnormal state.

4. The MCU-based multi-station parallel automated testing system according to claim 1, characterized in that: The product under test is a discrete semiconductor device.

5. The MCU-based multi-station parallel automated testing system according to claim 1, characterized in that: The core control unit uses an STM32F103ZET6 microcontroller, which is equipped with an 8MHz crystal oscillator as a clock reference.

6. The MCU-based multi-station parallel automated testing system according to claim 1, characterized in that: The communication module of the data interaction unit is a serial communication module with a baud rate of 9600bps, used to realize bidirectional data transmission between the core control unit and the parameter tester and the host computer software.

7. A multi-station parallel automated testing method for MCUs based on the system described in any one of claims 1-6, characterized in that, Includes the following steps: S1. The system powers on and initializes, then enters standby mode; S2. The user selects the target test channel and test mode through the human-computer interaction unit; the test modes include a single manual test mode for the selected channel and a sequential automatic loop test mode for all channels; S3. Based on the selected mode, the core control unit controls the path switching module in the channel isolation control unit and the test execution unit to construct a complete test path that includes the product under test and the parameter tester, and triggers the parameter tester to perform testing. S4. After the parameter tester completes the test, it feeds the data back to the core control unit and the host computer software through the data interaction unit. The core control unit parses the data and determines the result, and at the same time controls the status display module to update the indication status of the corresponding channel. S5. The test process ends and the system returns to standby mode.

8. The MCU-based multi-station parallel automated testing method according to claim 7, characterized in that: In the automatic cyclic test mode of step S3, the core control unit activates all channels in a preset order, and collects and provides feedback on data after the test of each channel is completed, until all channels are tested.

9. The MCU-based multi-station parallel automated testing method according to claim 7, characterized in that: The electrical performance parameters detected by the parameter tester include on-state voltage and reverse leakage current.

10. The MCU-based multi-station parallel automated testing method according to claim 7, characterized in that: In step S3, under the automatic loop test mode, after each channel test is completed, there is a 100ms delay before starting the next channel test to avoid module action conflicts; The test can be interrupted at any time and a reset operation can be performed. After the reset, the system returns to the initial standby state and the test channel automatically jumps to the initial channel.

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