Mini led substrate empty board test system and method

Abstract

This invention relates to a blank board testing system and method for Mini LED substrates, used for conducting continuity tests on the Mini LED substrate circuitry before chip packaging. The blank board testing system includes a Mini LED substrate, a blank board testing module, and a result display unit. This invention employs a method where the control unit for controlling the test path and the Mini LED substrate circuitry under test are contactably connected to any corner pad in a matrix of pads via a substrate connector to perform continuity testing. A single, simple operation allows for one-click testing of an entire substrate, resulting in short testing time and high efficiency. Furthermore, this connection control method is adaptable to all products using fully connected matrix pads, saving on personnel training costs and fixture development costs. In addition, this invention uses a storage and analysis unit to record the continuity test results of multiple Mini LED substrate circuits for overall analysis and visualization, facilitating timely detection and improvement of process defects and saving unnecessary costs.

Description

Technical Field

[0001] This invention relates to the field of electrical testing technology for Mini LED substrates, and specifically to a blank board testing system and method for Mini LED substrates. Background Technology

[0002] Conducting bare-board electrical testing on Mini LED substrates can identify functional defects in the circuitry early, which is beneficial for improving manufacturing processes, increasing product yield, and reducing costs. Currently, the industry commonly uses two methods for bare-board electrical testing of Mini LED substrates: moving probe testing and continuity fixture testing. Moving probe testing uses four to eight independently controlled probes to move to the pads being tested. Moving probe testing is more flexible, and one set of equipment can be used for products with different structures. However, due to the small pad spacing and numerous circuit connections of Mini LED substrates, moving probe testing is time-consuming, inefficient, cumbersome for operators, and prone to errors. Furthermore, the small pad spacing can easily lead to false readings. Continuity fixture testing requires the development of fixtures for each product structure. It is faster than flying probe testing and simpler for operators, but one fixture cannot be used for multiple product structures, and fixture development costs are high. On the other hand, neither moving probe testing nor continuity fixture testing has the function of storing test data from multiple Mini LED substrates for overall and intuitive analysis. There is a need to research a blank board testing method for Mini LED substrates that can solve the problems of long testing time and low efficiency, high development cost of testing tools, cumbersome operation and easy error by staff, and lack of intuitive data as a basis for process improvement. Summary of the Invention

[0003] To address the problems of long testing time, low efficiency, high cost of test tool development, cumbersome and error-prone operation for workers, and lack of intuitive data for process improvement in current bare board electrical testing of Mini LED substrates, this invention proposes a solution that uses a contact connector to connect to any corner pad in the matrix pads of the Mini LED substrate, controls the test circuit through a control unit, records the test results of multiple Mini LED substrates for overall analysis, and intuitively displays the circuit test results of each Mini LED substrate to select good products and displays the overall analysis results as a reference for diagnosing process defects.

[0004] The technical solution adopted by this invention to solve its technical problem is as follows:

[0005] In a first aspect, the present invention provides a blank board testing system for a Mini LED substrate, used to perform continuity testing on the Mini LED substrate circuitry before chip packaging. The blank board testing system includes: a Mini LED substrate, a blank board testing module, and a result display unit. The Mini LED substrate includes: substrate circuitry with matrix-style pads, each pad being independently connectable to the positive and negative terminals of the substrate circuitry. The matrix-style pads and full circuitry connection facilitate flexible configuration of different partitions for circuitry functional connections by the driver chip. The blank board testing module includes: a substrate connector for electrically connecting to the substrate circuitry, and a control unit for controlling continuity testing when the substrate connector is electrically connected to the substrate circuitry. The control unit can set up full-circuit testing with one click, resulting in high testing efficiency. The result display unit displays the continuity test results, which can be directly used for sorting and screening good and defective products.

[0006] Preferably, the method of electrically connecting the substrate connector to the substrate circuit includes: connecting the substrate connector to any corner pad of the matrix pads in a contact manner to power the substrate circuit and transmit connection signals between the control unit and the substrate circuit. The contact connection method is convenient for connecting and disconnecting, which can reduce testing time and improve efficiency. Due to the small spacing of the Mini LED pads, connecting the connector to the corner pads relatively improves the connectivity and reduces false tests. This connection method is applicable to all substrates with fully connected matrix pad circuits.

[0007] Preferably, the continuity test includes pad continuity testing and circuit continuity testing. The pad continuity test is performed by a control unit that tests the continuity of each pad. Since each pad is directly connected to the positive and negative terminals of the substrate circuit, performing the pad continuity test first allows for a quick and easy determination of the connection status of each pad with a single click. The circuit continuity test is performed by a control unit that starts from any corner pad of the matrix-shaped pads and traverses the circuit in a clockwise serpentine pattern, connecting the circuit to the diagonal pad opposite the starting point. Then, starting from that corner pad, it traverses the circuit in a counter-clockwise serpentine pattern, connecting the circuit to the diagonal pad opposite the starting point. By performing clockwise and counter-clockwise serpentine traversals from the same corner pad, the continuity of each circuit can be tested with a shorter route.

[0008] Preferably, the result display unit displays the continuity test results on the display screen included in the blank board test module. The display method is as follows: when the control unit controls the test of the set lines and pads, the display screen marks the lines and pads that are connected and the lines and pads that should be connected but are not connected, so as to intuitively display the test results and distinguish between good and bad products in real time.

[0009] Preferably, the blank board testing module also includes a storage and analysis unit for recording the conductivity test results of each Mini LED substrate and performing overall analysis. By displaying the overall analysis results in real time, process defects can be detected in a timely manner and process improvements can be made.

[0010] Preferably, each pad is coated with a die bond adhesive containing phosphor. The result display unit includes displaying the continuity test results on the pads. Specifically, when the control unit controls the testing of the set circuits and pads, the phosphor on the conductive pads emits light, thereby visually displaying the continuity of the circuit pads using the structural characteristics of the pads.

[0011] Secondly, the present invention also provides a method for testing the empty board of a Mini LED substrate. The method uses the empty board testing system of the first aspect to perform continuity testing on the Mini LED substrate circuitry, including the following steps: S1, connecting the substrate connector to any corner pad of the matrix pads on the Mini LED substrate; S2, the control unit initiates the pad continuity test, the result display unit displays the pad continuity test results, and the storage and analysis unit included in the empty board testing module records the pad continuity test results of each Mini LED substrate circuitry fed back by the control unit; S3, the control unit initiates the circuit continuity test, the result display unit displays the circuit continuity test results, and the storage and analysis unit records the circuit continuity test results of each Mini LED substrate circuitry fed back by the control unit; S4, extracting the circuit continuity test results recorded by the storage and analysis unit, selecting several Mini LED substrate circuitry continuity test records for overall analysis and visualizing the results, facilitating one-click connection testing, with short testing time and intuitive test results.

[0012] The beneficial effects of this invention are as follows:

[0013] Firstly, the present invention employs a method in which the control unit for controlling the test route and the Mini LED substrate circuit under test are connected to any corner pad in the matrix pads via a substrate connector for continuity testing. A single convenient connection and one-button operation control completes the continuity test of all circuits, and the test results are displayed intuitively by the result display unit. The test time is short and the efficiency is high.

[0014] Secondly, the present invention uses a storage analysis unit to record the continuity test results of multiple Mini LED base circuits and displays the results visually through a result display unit, which helps to promptly identify and improve process defects and reduce unnecessary costs.

[0015] Thirdly, the contactable connection method of the control unit and basic circuit adopted in this invention is simple to operate, can adapt to all products that use matrix pad full connection, and saves personnel training costs and fixture development costs. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the Mini LED substrate empty board testing system provided in an embodiment of the present invention;

[0017] Figure 2 This is a schematic diagram of the Mini LED substrate circuit connection provided in an embodiment of the present invention;

[0018] Figure 3 This is a schematic diagram of line traversal for conducting line continuity testing provided in an embodiment of the present invention;

[0019] Figure 4 This is a flowchart of the empty board testing method for Mini LED substrate provided in an embodiment of the present invention.

[0020] Attached image labels:

[0021] 1-Mini LED substrate; 11-Substrate circuitry; 12-Pads; 121-Corner pads; 122-Diagonal pads;

[0022] 2-Blank board test module; 21-Substrate connector; 22-Control unit;

[0023] 3-Results Display Unit;

[0024] 41 - Clockwise serpentine traversal route; 42 - Counterclockwise serpentine traversal route. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0026] The "empty board" referred to in this solution is a circuit board without any soldered components. The circuit board manufacturing process is lengthy, and defects such as short circuits, open circuits, and leakage are prone to occur during production. The Mini LED substrate 1, with its high-density, fine-pitch characteristics, is even more challenging to manufacture. If products with electrical defects are not promptly screened out during production and allowed to enter the manufacturing process, it will result in greater cost waste. Therefore, improving testing technology and timely process improvements are essential to reduce product scrap rates and increase yield. After the empty board is manufactured, if an open circuit on the substrate can be detected, the defect can be corrected by rewiring, or a Mini LED substrate 1 can be discarded. However, if the open circuit is not detected and is discovered during installation in equipment by downstream manufacturers, it wastes more time and material costs for them. If the problem is not discovered during equipment installation, it is only discovered after the entire product has entered the market, resulting in even greater cost losses. Therefore, high-quality, efficient empty board testing is crucial for timely detection of circuit defects. This solution aims to improve the current blank board testing technology, which suffers from long testing times, low efficiency, high fixture development costs, and reliance on intuition for process improvements without intuitive and accurate data.

[0027] Please refer to Figure 1 , Figure 2 This solution provides a blank board testing system for a Mini LED substrate 1, used to perform continuity testing on the Mini LED substrate circuitry 11 before chip packaging. The blank board testing system includes: a Mini LED substrate 1, a blank board testing module 2, and a result display unit 3. The Mini LED substrate 1 includes: substrate circuitry 11 containing matrix pads 12, each pad 12 being independently connectable to the positive and negative terminals of the substrate circuitry 11. The blank board testing module 2 includes: a substrate connector 21 for electrically connecting to the substrate circuitry 11, and a control unit 22 for controlling the continuity testing when the substrate connector 21 is electrically connected to the substrate circuitry 11. The result display unit 3 is used to display the continuity test results.

[0028] Specifically, the Mini LED substrate 1 features small pad spacing, a matrix arrangement, and each pad can be independently connected to the positive and negative terminals of the substrate lines 11. All substrate lines 11 are interconnected, and the application circuitry is controlled by a driver chip after installation in the device. Therefore, traditional flying probe testing or dedicated fixture testing is inefficient. The control unit 22 connects to the substrate lines 11, operating on the same principle as the driver chip controlling the circuitry after the substrate is installed in the device. Power is easily and conveniently connected via the substrate connector 21, allowing the control unit 22 to control the testing of all connected lines with a single button. Testing is completed automatically in a very short time, without the need to move flying probes, and with high accuracy.

[0029] Furthermore, the substrate connector 21 is electrically connected to the substrate line 11 by: contacting the substrate connector 21 to any corner pad 121 of the matrix pads to power the substrate line and transmitting a connection signal between the control unit 22 and the substrate line 11.

[0030] Specifically, to improve testing efficiency, conventional probe insertion testing is only suitable for testing a small number of substrates. For large-scale testing, a simple connection and disconnection method is required. Therefore, the substrate connector 21 is connected to the pads 12 of the substrate circuit 11 using a contactable connection method, such as adsorption, plug-in, snap-on, or spring-loaded connection. Based on the characteristic that each pad 12 is independently connected to the positive and negative terminals of the substrate circuit 11, connecting the substrate connector 21 to any pad 12 in the matrix of pads 12 allows control of all pads 12 and all circuit connections via the control unit 22. However, due to the small spacing between the pads 12, inserting the substrate connector 21 into the middle pad 12 is more likely to cause unnecessary damage by touching other pads 12 during the connection process compared to inserting it into a corner pad 121. Therefore, this solution uses the method of inserting the substrate connector 21 into a corner pad 121 for connection, resulting in less damage and a more convenient connection. The connection via the substrate connector 21 serves two purposes: firstly, to power the substrate circuit 11, and secondly, to transmit signals. Specifically, the control unit 22 transmits the connection signal to the substrate circuit 11, and the substrate circuit 11 feeds back the connection status of the set circuit and pad 12 to the control unit 22.

[0031] For further information, please continue to refer to [link / reference]. Figure 2 The continuity test includes pad continuity test and circuit continuity test. The pad continuity test method is as follows: the control unit 22 controls the continuity test of each pad 12 at a time.

[0032] Specifically, the testing process is set to perform pad continuity testing first, followed by circuit continuity testing. This is because if any pad 12 is found to be disconnected during the pad continuity testing stage, the Mini LED substrate 1 can be directly returned to the manufacturing process for repair or discarded, saving time spent on subsequent circuit continuity testing. Of course, whether to continue with subsequent circuit continuity testing when an open circuit is found at pad 12 can be set by the control unit 22.

[0033] Further, please refer to Figure 3 The continuity test method also includes: the control unit 22 controls the test to start from any corner pad 121 of the matrix pad 12, and connect the line to the diagonal pad 122 of the starting point in a clockwise serpentine traversal; then, starting from the starting corner pad 121, the line is connected to the diagonal pad 122 of the starting corner pad in a counterclockwise serpentine traversal.

[0034] Specifically, if no open circuit is found during the solder continuity test, based on the characteristic of the fully interconnected circuits between pads 12 of the Mini LED substrate 1, it does not necessarily mean that all circuits are conductive. Further circuit continuity testing is required. The purpose of the circuit continuity test is twofold: first, all circuits need to be traversed; second, the tested circuits should be as short as possible to ensure testing efficiency. Based on the characteristics of matrix pads and fully connected circuits, a two-dimensional array traversal method can be adopted, starting from any pad, such as a circular traversal or diagonal traversal. This solution uses any corner pad 121 as the starting point, first performing a clockwise serpentine traversal to the diagonal pad 122, and then starting from the starting corner pad 121 and performing a counterclockwise serpentine traversal. This method has the characteristics of traversing all circuits and having a relatively short traversal route, making it the preferred test circuit traversal method.

[0035] Furthermore, the result display unit 3 displays the continuity test results on the display screen included in the blank board test module 2. The method of displaying the continuity test results on the display screen is as follows: when the control unit 22 controls the testing of the set lines and pads, the display screen marks the lines and pads that are connected, and marks the lines and pads that should be connected but are not connected.

[0036] Specifically, after the substrate connector 21 is connected to the substrate circuit 11, the control unit 22 can automatically detect the structure of the substrate circuit 11 and simulate the overall circuit diagram of the substrate on the display screen. After the test is completed, the circuit connection status fed back by the test can be marked on the overall circuit diagram, that is, the connected circuit status and the unconnected circuit status can be marked. The display screen has the characteristics of real-time, intuitive and comprehensive display.

[0037] Furthermore, the blank board test module 2 also includes a storage and analysis unit for recording the conductivity test results of each Mini LED substrate and performing overall analysis.

[0038] Specifically, the storage and analysis unit is connected to the control unit 22 and the display screen, recording the continuity test results fed back to the control unit 22. When more than two Mini LED substrates 1 are recorded, a comprehensive analysis can be performed in real time, and the results are updated on the display screen. The storage and analysis unit can also be externally connected, such as by installing the storage and analysis unit on a host PC and then connecting the control unit to the host PC. This expands the storage capacity, and the number of Mini LED substrates 1 recorded can be unlimited, allowing for richer data analysis. Alternatively, the storage and analysis unit can be built into the blank board test module and externally connected to the host PC simultaneously. The built-in unit can display a brief overview of the overall analysis in real time, but the data volume is limited; the external unit can store an unlimited amount of data, allowing for more comprehensive analysis, but real-time performance may be affected.

[0039] Furthermore, each pad 12 is coated with die bond adhesive containing phosphor. The result display unit 3 includes displaying the continuity test results on the pad 12. Specifically, when the control unit 22 controls the testing of the set lines and pads, the phosphor on the conductive pad 12 emits light.

[0040] Specifically, applying a phosphor-containing die-attach adhesive to the pads serves as a guide for dividing different functional areas when soldering Mini LED chips. As a simplified application of the blank board testing system, the blank board testing module 2 can consist only of the substrate connector 21 and the control unit 22. Results are displayed directly using the characteristic of the Mini LED substrate 1 pads 12 emitting light when powered on. Alternatively, the display screen and the pads emitting light can simultaneously display the test results, allowing staff to directly filter and sort out defective products based on the pad display results.

[0041] Please refer to Figure 4 This solution also provides a method for testing the empty board of a Mini LED substrate 1. The method uses the empty board testing system described above to perform a continuity test on the Mini LED substrate circuit 11. The method includes the following steps: S1, connecting the substrate connector 21 to any corner pad 122 of the matrix pads 12 of the Mini LED substrate 1; S2, the control unit 22 starts the pad continuity test, the result display unit 3 displays the pad continuity test results, and the storage analysis unit included in the empty board testing module 2 records the pad continuity test results of each Mini LED substrate circuit 11 fed back by the control unit 22; S3, the control unit 22 starts the circuit continuity test, the result display unit 3 displays the circuit continuity test results, and the storage analysis unit records the circuit continuity test results of each Mini LED substrate circuit 11 fed back by the control unit 222; S4, extracting the circuit continuity test results recorded by the storage analysis unit, selecting several Mini LED substrate circuit 11 continuity test records for overall analysis and visualization of the results.

[0042] Specifically, one end of the substrate connector 11 is fixedly connected to the control unit 22, and the other end can be contactably connected to any one of the four corner pads 121 of the matrix pads 12 of the substrate circuit 11, thereby enabling connection to any pad and circuit of the substrate circuit 11. Contactless connection includes, but is not limited to, magnetic connection, insertion connection, spring contact connection, and snap-fit ​​connection, which features convenient connection and disconnection operations and improves testing efficiency. After the substrate connector 21 is connected to the control unit 22 and the substrate circuit 11, the control unit 22 first initiates a pad continuity test, that is, tests whether each pad 12 can be connected individually. Then, the control unit 22 initiates a circuit continuity test. The goal of the circuit continuity test is to traverse all circuits and pads using the shortest possible path. The substrate circuit 11 is similar to a two-dimensional array connection. The possible traversal methods include circular traversal, diagonal traversal, etc. This solution uses any corner pad 121 as the starting point, first performing a clockwise serpentine traversal to the diagonal pad 122 of the starting corner pad 121, and then starting from the starting point, performing a counterclockwise serpentine traversal to the diagonal pad 122. This method can traverse all circuit pads, and the traversal path is short, that is, the number of repeated lines is small, which has the advantage of high efficiency in achieving the test goal. It should be noted that both the pad continuity test and the circuit continuity test mentioned in this solution are controlled by the control unit 22 to control the routing of the connected circuits. Existing technologies perform blank board testing, directly reworking or discarding any Mini LED substrates found to be defective. They often rely on intuitive methods to summarize process defects for improvement. This solution stores the test records of each Mini LED substrate and performs overall analysis, providing accurate data references for process improvement.

[0043] For those skilled in the art, various other corresponding changes and modifications can be made based on the technical solutions and concepts described above, and all such changes and modifications should fall within the protection scope of the claims of this invention.

[0044] It should be noted that the embodiments described above are only some embodiments of the present invention, and not all embodiments. The singular forms "a," "the," "this time," "then," "previous," and "the" used in the embodiments and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

Claims

1. A bare board testing system for a Mini LED substrate, used to perform continuity testing on the circuitry of the Mini LED substrate before chip packaging, characterized in that, The empty board testing system includes: a Mini LED substrate, an empty board testing module, and a result display unit; The Mini LED substrate includes: a substrate circuit containing a matrix of pads, each pad being independently connected to the positive and negative terminals of the substrate circuit; The blank board testing module includes: a substrate connector for electrically connecting to the substrate circuitry, and a control unit for controlling the continuity test when the substrate connector is electrically connected to the substrate circuitry. The method of electrically connecting the substrate connector to the substrate circuit includes: contacting the substrate connector to any corner pad of the matrix pad to power the substrate circuit and transmitting connection signals between the control unit and the substrate circuit. The continuity test includes a line continuity test. The line continuity test method is as follows: the control unit controls the test to start from any corner pad of the matrix pad, and traverse the line in a clockwise serpentine manner to connect to the diagonal pad opposite the starting point; then, starting from the starting corner pad, traverse the line in a counterclockwise serpentine manner to connect to the diagonal pad opposite the starting corner pad. The result display unit is used to display the continuity test results. The method of displaying the continuity test results is as follows: when the control unit controls the test of the set lines and pads, the display screen marks the lines and pads that are connected and the lines and pads that should be connected but are not connected. After the substrate connector is connected to the substrate circuit, the control unit detects the structure of the substrate circuit and simulates the overall circuit diagram of the substrate on the display screen. After the test is completed, the control unit marks the circuit connection status fed back by the test on the overall circuit diagram to mark the connected circuit status and / or the unconnected circuit status.

2. The blank board testing system according to claim 1, characterized in that, The continuity test also includes pad continuity testing.

3. The blank board testing system according to claim 2, characterized in that, The continuity test method for the pads is as follows: the continuity of each pad is tested by the control unit.

4. The blank board testing system according to claim 1, characterized in that, The empty board testing module also includes a storage and analysis unit, which records the conductivity test results of each Mini LED substrate and performs overall analysis.

5. The blank board testing system according to claim 1, characterized in that, Each pad is coated with die bond adhesive containing phosphor. The result display unit includes displaying the continuity test results on the pads. Specifically, when the control unit controls the testing of the set lines and pads, the phosphor on the conductive pads emits light.

6. A method for testing the empty board of a Mini LED substrate, wherein the method uses the empty board testing system as described in any one of claims 1-5 to perform continuity testing on the circuitry of the Mini LED substrate, characterized in that, The method includes the following steps: S1, connect the substrate connector to any corner pad of the matrix pads of the Mini LED substrate; the substrate connector is electrically connected to the substrate circuit by: contacting the substrate connector to any corner pad of the matrix pads to power the substrate circuit and transmit connection signals between the control unit and the substrate circuit. The continuity test includes a line continuity test. The line continuity test method is as follows: the control unit controls the test to start from any corner pad of the matrix pad, and traverse the line in a clockwise serpentine manner to connect to the diagonal pad opposite the starting point; then, starting from the starting corner pad, traverse the line in a counterclockwise serpentine manner to connect to the diagonal pad opposite the starting corner pad. S2, the control unit starts the pad continuity test, the result display unit displays the pad continuity test results, and the storage and analysis unit included in the blank board test module records the pad continuity test results of each Mini Led substrate circuit fed back by the control unit; S3, the control unit starts the circuit continuity test, the result display unit displays the circuit continuity test results, and the storage and analysis unit records the circuit continuity test results of each Mini Led substrate circuit fed back by the control unit; The method for displaying the continuity test results is as follows: when the control unit controls the testing of the set lines and pads, the display screen indicates the lines and pads that are connected, and indicates the lines and pads that should be connected but are not connected. In this process, after the substrate connector is connected to the substrate circuit, the control unit detects the structure of the substrate circuit and simulates the overall circuit diagram of the substrate on the display screen. After the test is completed, the control unit marks the circuit connection status fed back by the test on the overall circuit diagram to mark the connected circuit status and / or the unconnected circuit status. S4. Extract the circuit continuity test results recorded by the storage analysis unit, select several Mini LED substrate circuit continuity test records to conduct overall analysis and display the visualization results.

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