Device suitable for testing bending aging life of FPC (Flexible Printed Circuit)

Abstract

The invention aims to provide the device suitable for testing the bending aging life of the FPC, the cost is low, the adaptation rate is high, the testing efficiency is high, the testing precision is high, the on-off state of the bending aging test of the FPC can be monitored in real time, and the accurate tracing of the production process is realized. The system comprises an upper computer and a test module, the upper computer is connected with the test module through a network switch, the test module comprises a differential amplification circuit, an analog-to-digital conversion circuit, a digital-to-analog conversion output circuit, a comparator circuit and a control unit circuit, and a product to be tested is connected with the input end of the differential amplification circuit. The input end of the comparator circuit is connected with the differential amplification circuit, the analog-to-digital conversion circuit and the digital-to-analog conversion output circuit, the output end of the comparator circuit is connected with the control unit circuit, and the control unit circuit is connected with the network switch; the invention is applied to the technical field of FPC detection.

Description

Technical Field

[0001] This invention applies to the technical field of FPC testing, and particularly relates to a device suitable for testing the bending aging life of FPCs. Background Technology

[0002] FPC (Flexible Printed Circuit) is a bendable printed circuit board made of polyimide or polyester film. It is characterized by its thinness, lightness, and bend resistance. Today, FPC, with its core advantages of being thin, flexible, and customizable, has become a key component in consumer electronics, automotive electronics, medical devices, aerospace, and other fields. Its bending reliability directly determines the lifespan of the end product and the user experience. As the industry moves towards thinner, more foldable, and extreme environment adaptability, the contradiction between the technical requirements for FPC bending aging life testing and the shortcomings of existing equipment is becoming increasingly prominent. Traditional testing relies on fixing one end of the FPC and having the other end rotate in a circular motion along a pivot axis to simulate the opening and closing of a hinge tens or even hundreds of thousands of times. Although this method is simple in structure and low in cost, it cannot capture micro-cracks in real time, and the stress distribution is uneven, failing to simulate real-world bending conditions, and the force at both ends is difficult to control. However, existing technologies have the following drawbacks: A. If the FPC is assembled into a finished product and then tested as a whole, and the whole machine is found to be malfunctioning, it will need to be disassembled for repair or scrapped, which will reduce the production pass rate and increase the production cost. B. If a folding aging test is performed on the FPC, the detection function is limited, and most of the device's functions cannot be detected. C. It requires the use of customized tools to transfer test points and then manually test them one by one. Testing all the functions of the product takes too long, is inefficient, and is prone to missed or false detections. This is not conducive to automated production and makes it difficult to control the quality of the production process.

[0003] For example, Chinese Patent CN113985609A discloses a head-mounted display device and its temple component, frame component and control method. It uses contact power supply to realize the power transmission between the temple component and the frame component, avoiding signal attenuation caused by bending of FPC or other wires, improving the reliability and service life of the head-mounted display device, and thus enabling detection of contact power supply.

[0004] However, in existing technologies, it is impossible to accurately determine the number of bends at which the actual wire breakage occurs in an FPC during bending aging life test; in addition, latent damage may not completely lead to a break in the circuit during offline detection, creating the hidden danger of "passing the test but failing prematurely in actual use", which seriously affects the accuracy and reliability of FPC reliability verification.

[0005] For example, Chinese patent application number CN2025115788491 discloses a real-time wire breakage detection method based on bending aging life test. During dynamic bending, the output circuit of the digital-to-analog converter sets different reference voltage input comparators according to the different Vmeas voltages of different branch circuits collected by the analog-to-digital converter. If a branch circuit of the device under test breaks or has a micro-fracture during bending, the output of the differential amplifier circuit of the corresponding circuit will increase. When the output of the differential amplifier circuit is greater than the reference voltage set by the digital-to-analog converter, the output of the comparator circuit will change from low level to high level. The control unit circuit continuously monitors and records the state changes of the corresponding GPIO in real time during bending, thereby detecting whether the device under test has a breakage in real time. However, this detection method is prone to causing clamping damage to the product and has the disadvantages of insufficient accuracy, monitoring lag, and poor adaptability.

[0006] Therefore, it is necessary to provide a device suitable for FPC bending aging life testing that is low in cost, highly adaptable, highly efficient, and highly accurate, capable of real-time monitoring of the on / off status of FPC bending aging test, and achieving precise traceability of the production process. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a device suitable for FPC bending aging life testing, which is low in cost, highly adaptable, highly efficient and accurate in testing, and can monitor the on / off status of FPC bending aging test in real time, so as to realize accurate traceability of the production process.

[0008] The technical solution adopted in this invention is as follows: This invention includes a host computer and a test module. The host computer is connected to the test module via a network switch. The test module includes a differential amplifier circuit, an analog-to-digital converter circuit, a digital-to-analog converter output circuit, a comparator circuit, and a control unit circuit. The product under test (DUT) is connected to the input terminal of the differential amplifier circuit. The input terminal of the comparator circuit is connected to the differential amplifier circuit, the analog-to-digital converter circuit, and the digital-to-analog converter output circuit. The output terminal of the comparator circuit is connected to the control unit circuit. The control unit circuit is connected to the network switch. The differential amplifier circuit collects various data from the product under test. The analog-to-digital converter (ADC) converts the acquired analog signal into a digital signal and reads the amplified differential voltage. The ADC output circuit provides a specified reference voltage to the comparator circuit. The comparator circuit detects the output voltage of the differential amplifier circuit in real time and compares it with the threshold Vref set by the ADC output circuit. When the product under test breaks, the corresponding signal impedance increases, thereby causing the output of the differential amplifier circuit to increase. When the output of the differential amplifier circuit exceeds the set threshold, the comparator circuit outputs a high level. As can be seen from the above solution, this application, as a bending aging life testing device for FPC flexible circuit boards, has the advantages of non-destructive clamping, precise driving, real-time monitoring, multi-station collaboration, and safety protection. It effectively solves the drawbacks of simply folding and then powering on the flexible board for testing, which cannot simultaneously perform folding and power-on testing. It also effectively solves the problems of missed detections, false detections, and low efficiency caused by manual testing with customized tools. It enables quality control of the production process, precise traceability of the production testing process, and refined production. It also provides data support for product iteration design. The structure is easily expandable, allowing for the simultaneous testing of a large number of products. One station can complete various functional tests on FPC bending. Test data can be easily linked to products using the product's serial number (SN), achieving precise traceability of the production testing process. This device can simultaneously perform functional tests on multiple products; it helps improve production efficiency, product qualification rate, and product quality; it reduces production costs and significantly reduces the decline in production qualification rate and product quality caused by human factors; it facilitates statistical analysis of test data, which is helpful for product iteration design; and it achieves precise traceability of the production process, far superior to the current method of traceability by production batch.

[0009] In a preferred embodiment, the device for testing the bending aging life of FPC further includes an electromechanical controller module. The host computer is connected to the electromechanical controller module via the network switch. The electromechanical controller module includes an MCU module, which is connected to a positioning controller module, a solenoid valve drive module, and a motor drive module. The solenoid valve drive module and the motor drive module are both connected to the positioning controller module, and the positioning controller module is positioned in conjunction with the product under test.

[0010] In a preferred embodiment, the positioning controller module includes a limit sensor and a motor controller. The output of the motor controller is connected to a drive motor. The limit sensor cooperates with the product under test for limiting, and the motor controller controls the drive motor to move the product under test to a designated position.

[0011] In a preferred embodiment, the host computer is connected to a display component, which includes indicator lights, buttons, and an input / output control module. The indicator lights and buttons are both connected to the input / output control module.

[0012] In a preferred embodiment, the host computer is connected to the display component via a USB hub interface, the USB hub interface is connected to an input module, and the network switch is connected to a shared function control module.

[0013] In a preferred embodiment, the FPC bending aging life testing device further includes an adapter plate module, through which the product under test is connected to the testing module.

[0014] In a preferred embodiment, the test module further includes a time-division multiplexed programmable channel selection switch matrix, and the adapter board module is connected to the differential amplifier circuit and the control unit circuit via the time-division multiplexed programmable channel selection switch matrix. Attached Figure Description

[0015] Figure 1 This is a system topology block diagram of the present invention; Figure 2 This is a schematic diagram of the test module. Figure 3 This is a schematic block diagram of the electromechanical controller module; Figure 4 This is a schematic block diagram of the positioning controller module; Figure 5 This is a schematic diagram of the display component. Detailed Implementation

[0016] like Figures 1 to 2As shown, in this embodiment, the present invention includes a host computer 1 and a test module 2. The host computer 1 is connected to the test module 2 via a network switch 3. The test module 2 includes a differential amplifier circuit 5, an analog-to-digital converter circuit 6, a digital-to-analog converter output circuit 7, a comparator circuit 8, and a control unit circuit 9. The product under test 10 is connected to the input terminal of the differential amplifier circuit 5. The input terminal of the comparator circuit 8 is connected to the differential amplifier circuit 5, the analog-to-digital converter circuit 6, and the digital-to-analog converter output circuit 7. The output terminal of the comparator circuit 8 is connected to the control unit circuit 9. The control unit circuit 9 is connected to the network switch 3. The differential amplifier circuit 5 collects data from the product under test. The voltages at both ends of each signal of product 10 are amplified and output according to a set gain. The analog-to-digital converter circuit 6 converts the acquired analog signals into digital signals and reads the amplified differential voltage. The digital-to-analog converter output circuit 7 provides a specified reference voltage to the comparator circuit 8. The comparator circuit 8 detects the output voltage of the differential amplifier circuit 5 in real time and compares it with the threshold Vref set by the digital-to-analog converter output circuit 7. When the product under test 10 breaks, the corresponding signal impedance increases, thereby causing the output of the differential amplifier circuit 5 to increase. When the output of the differential amplifier circuit 5 exceeds the set threshold, the comparator circuit 8 outputs a high level.

[0017] The control software of the host computer 1 acts as the overall control system, controlling the electromechanical controller module 11 to accurately locate the product, allowing the product under test 10 to establish a test link with the test module 2. The control software of the host computer 1 then establishes the basic original information of each product under test 10 by controlling the SN input module, and then associates the test data of the product function with the basic original information through the USB HUB interface 23, the test module 2, and the common function control module 25, thus completing the functional testing of the product and the quality traceability control of the production process.

[0018] The test module 2 is connected to the host computer 1 via the network switch 3, and the test is controlled by the test software of the host computer 1 to complete the test; it parses the data sent by the host computer 1, completes the test of the corresponding product according to the parsed information, and returns the relevant test information of the product to the host computer 1 for statistical analysis.

[0019] The differential amplifier circuit 5 acquires the voltages at both ends of each signal of the product under test 10 and amplifies the output voltage according to the set gain. The analog-to-digital converter circuit 6 converts the acquired analog signal into a digital signal, reads the amplified differential voltage, and prepares for setting the reference voltage of the digital-to-analog converter output circuit 7 during the folding process. The digital-to-analog converter output circuit 7 provides a specified reference voltage for each high-speed comparator. The comparator circuit 8 detects the output voltage of the differential amplifier circuit 5 in real time and compares it with the threshold Vref set by the digital-to-analog converter output circuit 7. Once the product under test 10 experiences a break or micro-break, the corresponding signal impedance increases, thereby causing the differential amplifier circuit 5 to also increase. When the output of the differential amplifier circuit 5 exceeds the set threshold, the comparator circuit 8 quickly outputs a high level or pulse. The control unit circuit 9 undertakes the functions of time-division multiplexing programmable channel selection switch matrix, ADC data acquisition, DAC output control, and dynamic real-time monitoring of high-speed comparator output.

[0020] like Figures 1 to 3 As shown, in this embodiment, the device for testing the bending aging life of FPC further includes an electromechanical controller module 11. The host computer 1 is connected to the electromechanical controller module 11 via the network switch 3. The electromechanical controller module 11 includes an MCU module 12. The MCU module 12 is connected to a positioning controller module 13, a solenoid valve drive module 14, and a motor drive module 15. The solenoid valve drive module 14 and the motor drive module 15 are both connected to the positioning controller module 13. The positioning controller module 13 is positioned and cooperates with the product under test 10.

[0021] The solenoid valve drive module 14 drives the solenoid valve of the positioning controller module 13; the motor drive module 15 drives the motor controller of the positioning controller module 13. The MCU module 12 receives and processes various status information sent by the sensors of the product positioning control component and communicates with the host computer 1. It performs correct control based on the information from the host computer 1 and sends relevant information to the host computer 1 so that the host computer 1 can execute test operations. The electromechanical controller module 11 receives and processes control information from the computer, and controls the positioning controller module 13 to connect the product under test 10 to the device based on this information; it also receives product position information from the positioning controller module 13 to issue accurate control operations (such as product QR code recognition and start testing). The electromechanical controller module 11 transmits the current status information of the device to the display component 19. The electromechanical controller module 11 receives test commands from the display component 19, and after determining that the test command is valid, transmits it to the host computer 1, which then controls the completion of the product test operation.

[0022] like Figure 4 As shown, in this embodiment, the positioning controller module 13 includes a limit sensor 16 and a motor controller 17. The output terminal of the motor controller 17 is connected to a drive motor 18. The limit sensor 16 cooperates with the product under test 10 in a limiting manner. The motor controller 17 controls the drive motor 18 to move the product under test 10 to a designated position.

[0023] The limit sensor 16 is used by the MCU module 12 to record the position as the "starting position" when the moving part begins to move, ensuring that the bending start point and station positioning are consistent for each test, preventing non-aging damage (such as wire breakage or substrate cracking) to the FPC sample due to mechanical collision, and ensuring the authenticity of the test data. The motor controller 17 controls the drive motor 18 to move the product to the designated position according to the instructions transmitted from the relay controller, so as to place or remove the product or to test the product.

[0024] like Figure 5 As shown, in this embodiment, the host computer 1 is connected to a display component 19, which includes an indicator light 20, a button 21, and an input / output control module 22. Both the indicator light 20 and the button 21 are connected to the input / output control module 22. The indicator light 20 outputs the current state of the device, and the button 21 inputs the operation information that the operator expects the device to perform, such as test or reset. The input / output control module 22 controls the indicator light 20 or the speaker to output relevant information according to the instructions from the motor controller 17, transmitting the control information input by the operator to the motor controller 17 for control.

[0025] like Figure 1 As shown, in this embodiment, the host computer 1 is connected to the display component 19 via a USB HUB interface 23. The USB HUB interface 23 is connected to an input module 24, and the network switch 3 is connected to a shared function control module 25. The input module 24 is an SN input module. The control software of the host computer 1 acts as a general control system, controlling the electromechanical controller module 11 to accurately locate the product, allowing the product under test 10 to establish a test link with the test module 2. The control software of the host computer 1 then establishes the basic original information of each product under test 10 by controlling the SN input module, and then associates the test data of the product function with the basic original information through the USB HUB interface 23, the test module 2, and the shared function control module 25, thus completing the functional testing of the product and the quality traceability control of the production process.

[0026] like Figure 1As shown, in this embodiment, the FPC bending aging life testing device further includes an adapter plate module 27, through which the product under test 10 is connected to the test module 2. The adapter plate module 27 introduces the product from the product under test 10 into the test control module, providing a test link for product testing.

[0027] like Figure 1 As shown, in this embodiment, the test module 2 further includes a time-division multiplexed programmable channel selection switch matrix 26. The adapter board module 27 is connected to the differential amplifier circuit 5 and the control unit circuit 9 via the time-division multiplexed programmable channel selection switch matrix 26. The time-division multiplexed programmable channel selection switch matrix 26 selects the enabled / conducted / disabled circuit under test through a GPIO port.

[0028] Although the embodiments of the present invention are described with reference to actual solutions, they do not constitute a limitation on the meaning of the present invention. Modifications to the embodiments and combinations with other solutions based on this specification will be obvious to those skilled in the art.

Claims

1. A device for testing the bending aging life of FPC, comprising a host computer (1) and a test module (2), wherein the host computer (1) is connected to the test module (2) via a network switch (3), characterized in that: The test module (2) includes a differential amplifier circuit (5), an analog-to-digital converter circuit (6), a digital-to-analog converter output circuit (7), a comparator circuit (8), and a control unit circuit (9). The product under test (10) is connected to the input terminal of the differential amplifier circuit (5). The input terminal of the comparator circuit (8) is connected to the differential amplifier circuit (5), the analog-to-digital converter circuit (6), and the digital-to-analog converter output circuit (7). The output terminal of the comparator circuit (8) is connected to the control unit circuit (9). The control unit circuit (9) is connected to the network switch (3). The differential amplifier circuit (5) collects the voltages at both ends of each signal of the product under test (10) and sets them according to the parameters. The set gain amplification output voltage is determined; the analog-to-digital converter circuit (6) converts the acquired analog signal into a digital signal and reads the amplified differential voltage; the digital-to-analog converter output circuit (7) provides a specified reference voltage to the comparator circuit (8); the comparator circuit (8) detects the output voltage of the differential amplifier circuit (5) in real time and compares it with the threshold Vref set by the digital-to-analog converter output circuit (7). When the product under test (10) breaks, the corresponding signal impedance increases, thereby causing the output of the differential amplifier circuit (5) to increase. When the output of the differential amplifier circuit (5) exceeds the set threshold, the comparator circuit (8) outputs a high level.

2. The device for testing the bending aging life of FPC according to claim 1, characterized in that, The device for testing the bending aging life of FPC also includes an electromechanical controller module (11). The host computer (1) is connected to the electromechanical controller module (11) via the network switch (3). The electromechanical controller module (11) includes an MCU module (12). The MCU module (12) is connected to a positioning controller module (13), a solenoid valve drive module (14), and a motor drive module (15). The solenoid valve drive module (14) and the motor drive module (15) are both connected to the positioning controller module (13). The positioning controller module (13) is positioned and cooperates with the product under test (10).

3. The device for testing the bending aging life of FPC according to claim 2, characterized in that, The positioning controller module (13) includes a limit sensor (16) and a motor controller (17). The output end of the motor controller (17) is connected to a drive motor (18). The limit sensor (16) cooperates with the product under test (10) in a limit position. The motor controller (17) controls the drive motor (18) to move the product under test (10) to a designated position.

4. The device for testing the bending aging life of FPC according to claim 2, characterized in that, The host computer (1) is connected to a display component (19), which includes an indicator light (20), a button (21), and an input / output control module (22). The indicator light (20) and the button (21) are both connected to the input / output control module (22).

5. The device for testing the bending aging life of FPC according to claim 4, characterized in that, The host computer (1) is connected to the display component (19) via a USB HUB interface (23). The USB HUB interface (23) is connected to an input module (24), and the network switch (3) is connected to a shared function control module (25).

6. The device for testing the bending aging life of FPC according to claim 1, characterized in that, The FPC bending aging life test device also includes an adapter plate module (27), and the product to be tested (10) is connected to the test module (2) via the adapter plate module (27).

7. The device for testing the bending aging life of FPC according to claim 6, characterized in that, The test module (2) also includes a time-division multiplexed programmable channel selection switch matrix (26), and the adapter board module (27) is connected to the differential amplifier circuit (5) and the control unit circuit (9) via the time-division multiplexed programmable channel selection switch matrix (26).

Images