Test system for Mini LED driving chip

Abstract

The utility model provides a test system for Mini LED drive chips, which is applied to the technical field of liquid crystal display and specifically comprises a host, an FPGA (field programmable gate array) master control module, a plurality of Mini LED drive chips, a plurality of cement resistors and a plurality of LED lamp beads with the same number as the cement resistors, then, through a mode of adding a cement resistor and an LED lamp bead in each channel of each Mini LED driving chip, the test requirement difference of different clients is considered on the test system, and through a mode of further adding an FPGA main control module, an automatic return circuit mechanism is added in the test system; wherein the host is in communication connection with the FP GA main control module through one path of UART bus so as to send a test signal to the FPGA main control module or receive the running state of each Mini LED driving chip returned by the FPGA main control module in real time, so that high-temperature and high-humidity accurate test and automatic recording of test results are realized, manpower and material resources are saved, and the test efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of liquid crystal display, in particular to a test system for Mini LED driver chips. Background Art

[0002] As a new backlight technology, Mini LED backlight has performance advantages such as high brightness, high contrast, low power consumption, and high color gamut compared with traditional backlights. This enables terminal display products to present clearer, higher-contrast images and deeper details. In the Mini LED backlight system, the Mini LED driver chip is one of its core components.

[0003] After the chip is designed and produced, testing the various performance indicators of the chip through a chip test circuit is an important link in chip design and the basis for evaluating whether the chip meets the design requirements. Among them, the high-temperature and high-humidity reliability test of the Mini LED driver chip is particularly important. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a test system for Mini LED driver chips. By adding cement resistors and LED beads to each channel of each Mini LED driver chip, the test requirements differences of different customers are considered in the test system. Further, by adding an FPGA main control module, an automatic feedback circuit mechanism is added to the test system, so as to achieve accurate testing of high temperature and high humidity, automatic recording of test results, and improve the test efficiency.

[0005] To solve the above technical problems, the utility model provides a test system for Mini LED driver chips, which specifically includes: a host computer, an FPGA main control module, multiple Mini LED driver chips, multiple cement resistors, and multiple LED beads.

[0006] Among them, the host computer, the FPGA main control module, and the multiple Mini LED driver chips are sequentially connected one by one. And each channel of each Mini LED driver chip is sequentially connected to at least one of the cement resistors and at least one of the LED beads respectively, so as to form a multi-channel automatic feedback test circuit in which the cement resistors and the LED beads included in each channel are connected in parallel and then connected to each Mini LED driver chip. And in each of the automatic feedback test circuits, the host computer is communicatively connected to the FPGA main control module through 1-way UART bus to send a test signal to the FPGA main control module or receive the operating state of each Mini LED driver chip that is real-time feedback by the FPGA main control module.

[0007] In some alternative examples, the FPGA master control module includes: an FPGA master control chip, a power supply unit, and a level conversion unit;

[0008] The power supply unit is connected to the multiple Mini LED driver chips and the level conversion unit, and includes a plurality of first output terminals having the same number as the Mini LED driver chips and a second output terminal. Among them, one first output terminal is correspondingly connected to one Mini LED driver chip to provide a working voltage to the Mini LED driver chip, and the second output terminal is connected to the input terminal of the level conversion unit to step down the voltage of the power supply unit and provide a working voltage to the FPGA master control chip through the output terminal of the level conversion unit.

[0009] In some alternative examples, the model of the FPGA master control chip includes GW1N-UV9-QN48.

[0010] In some alternative examples, the multiple Mini LED driver chips are connected in cascade; the first Mini LED driver chip among the multiple Mini LED driver chips is connected to the FPGA master control chip, and the first Mini LED driver chip is configured to receive all the control instructions corresponding to the Mini LED driver chips sent by the FPGA master control chip and send the control instructions corresponding to the other Mini LED driver chips to the next Mini LED driver chip.

[0011] In some alternative examples, the multiple Mini LED driver chips are connected through a serial interface.

[0012] In some alternative examples, the model of the Mini LED driver chip includes CX5831.

[0013] In some alternative examples, each Mini LED driver chip includes a plurality of channels, and the number of cement resistors and LED beads connected to each Mini LED driver chip is the same as the number of its channels.

[0014] In some alternative examples, each Mini LED driver chip includes a plurality of channels, the number of cement resistors connected to each Mini LED driver chip is the same as the number of its channels, and the number of LED beads connected to each Mini LED driver chip is N times the number of its channels, where N is greater than or equal to 2.

[0015] In some of the optional examples, the model of the LED lamp beads includes LW_M67C, and the cement resistor includes a color ring resistor with a resistance value of 1K ohms.

[0016] In some of the optional examples, the level conversion unit includes a voltage regulator power supply LDO, and the voltage regulator power supply LDO includes a power supply voltage regulator chip U7.

[0017] Compared with the prior art, the utility model has at least the following technical effects:

[0018] As described above, the utility model provides a test system for a Mini LED driver chip, which adds a multi-channel automatic feedback test circuit on the basis of the existing test circuit that can only test a single Mini LED driver chip. At the same time, considering the differences in test requirements of different customers in the test system, two load modes of cement resistors and LED lamp beads are set in parallel for each channel of each Mini LED driver chip to be tested in each automatic feedback test circuit. Thus, by using the cement resistor with high electrical characteristic consistency, when the LED lamp beads connected to a certain channel are affected by high temperature and high humidity and cannot accurately reflect the test results, the operation state of this channel is reflected by using this cement resistor, that is, the reliability of the high temperature and high humidity test of the Mini LED driver chip is improved.

[0019] Moreover, the utility model also adds an FPGA main control module to the test system, and then reads the internal state of each chip under test in real time through the UART bus, and records, statistics and gives early warning prompts for it, that is, an automatic feedback circuit mechanism is added to the test system. Thus, it is not necessary for testers to observe and register every day, and the test results of each Mini LED driver chip can be automatically obtained, recorded and displayed, that is, the automatic recording of test results is realized, manpower and material resources are saved, and the test efficiency is improved. Description of the Drawings

[0020] Figure 1 It is a circuit structure block diagram of the test system for the Mini LED driver chip provided in the embodiment of the utility model.

[0021] Figure 2 It is a partial circuit diagram of the Mini LED driver chip provided in the embodiment of the utility model.

[0022] Figure 3 It is a connection circuit diagram of multiple Mini LED driver chips, multiple cement resistors and multiple LED lamp beads provided in the embodiment of the utility model. Detailed Embodiment

[0023] The following describes the implementation manners of the present utility model through specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present utility model from the content disclosed in this specification. The present utility model can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present utility model.

[0024] It should be noted that the diagrams provided in this embodiment only illustrate the basic structure of the present utility model in a schematic manner, that is, only the components related to the present utility model are shown in the diagrams, rather than being drawn according to the number, state, and size of the components in actual implementation. The types, quantities, and proportions of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex. Therefore, the following description should be understood as broad knowledge for those skilled in the art and should not be construed as a limitation to the present utility model.

[0025] In the description of the present utility model, it should be noted that the orientation or positional relationships indicated by terms such as "center", "middle", "outer periphery", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the devices, figures, material layers, or elements referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

[0026] Please refer to Figure 1 , Figure 1 , which is the circuit structure block diagram of the test system for the Mini LED driver chip provided in the embodiment of the present utility model. As Figure 1 shown, the test system for the Mini LED driver chip provided by the present utility model may specifically include: a host, an FPGA main control module, a plurality of Mini LED driver chips, a plurality of cement resistors, and a plurality of LED beads having the same number as the cement resistors.

[0027] As an example, the plurality of Mini LED driver chips can be specifically enumerated one by one with Mini LED driver chip - n, such as Mini LED driver chip - 1, Mini LED driver chip - 2, Mini LED driver chip - 3, Mini LED driver chip - 4,..., Mini LED driver chip - n; the FPGA main control module may specifically include: an FPGA main control chip, a power supply unit, and a level conversion unit (not shown in the figure).

[0028] In this embodiment, the host, the FPGA main control module, and the multiple Mini LED driver chips are connected in sequence one by one. That is, the output end of the host is connected to an input end of the FPGA main control module through a 1-way UART bus to achieve a bidirectional communication connection between the host and the FPGA main control chip in the FPGA main control module. An output end of the FPGA main control chip is connected to an input end of the first Mini LED driver chip among the multiple Mini LED driver chips. The input end of the first Mini LED driver chip (such as Mini LED driver chip - 1) has multiple output ends, and one of its output ends is connected to the input end of the next Mini LED driver chip (such as Mini LED driver chip - 2) in series through a serial interface, and so on until the multiple Mini LED driver chips are cascaded (i.e., in series). Among them, the VLED signal ( Figure 1 abbreviated as VLED in

[0029] ) is used to provide working voltage for each LED lamp bead and cement resistor. Figure 2 As shown Figure 2 in the partial example circuit diagram of the Mini LED driver chip provided in the embodiment of the present invention. Exemplarily, the level conversion unit can be a voltage stabilizing power supply LDO, and the voltage stabilizing power supply LDO can be a power voltage stabilizing chip U7.

[0030] Working principle: During a certain test, the first Mini LED driver chip (such as Mini LED driver chip - 1) among the multiple Mini LED driver chips receives the control instructions sent by the FPGA master chip for each of the Mini LED driver chips (chips to be tested). After retaining the control instructions corresponding to itself, it sends the control instructions corresponding to the remaining Mini LED driver chips to the next Mini LED driver chip (such as Mini LED driver chip - 2) connected in series with it. And this next Mini LED driver chip, after receiving the control instructions sent by the first Mini LED driver chip excluding the control instructions corresponding to the first Mini LED driver chip itself, operates in the same way as the first Mini LED driver chip, only saves the control instructions corresponding to itself, and further sends the remaining control instructions to the next Mini LED driver chip (such as Mini LED driver chip - 3), and so on, until the last Mini LED driver chip (such as Mini LED driver chip - n) among the multiple Mini LED driver chips receives the control instructions sent by the FPGA master chip. Then, each of the Mini LED driver chips performs corresponding high-temperature and high-humidity tests on the cement resistors (loads) and LED beads (loads) connected to each of its channels based on the control instructions.

[0031] In this embodiment, each of the Mini LED driver chips may specifically include multiple channels, and each of its channels is connected to a cement resistor and an LED bead. The number of cement resistors and LED beads connected between the multiple channels may be the same or different. As an example, the number of cement resistors and LED beads connected to each Mini LED driver chip is the same as the number of its channels, that is, each channel of each Mini LED driver chip is respectively connected in parallel with a cement resistor and an LED bead. In other embodiments, the number of cement resistors and LED beads connected to each Mini LED driver chip may not be the same as the number of its channels, that is, each channel of each Mini LED driver chip may be respectively connected in parallel with a cement resistor and multiple LED beads. For example, Figure 2 as shown, each channel may be connected to a cement resistor and two LED beads. Of course, in other embodiments, each channel may also be connected to a cement resistor and N LED beads, where N is greater than or equal to 2, such as N being 3, 4, 5, 6, 7, etc., but not limited thereto.

[0032] In this embodiment, the host sends a test signal to the FPGA master chip in the FPGA master module at the start of the test, and reads in real time the operating status (or working conditions) of each MiniLED driver chip returned by the FPGA master chip in the FPGA master module during the test, and synchronously records in real time the operating status of the Mini LED driver chip under test; the FPGA master module is used to generate the control instructions and grayscale instructions required for testing the Mini LED driver chip, so as to read back the internal registers of each Mini LED driver chip in real time to obtain the internal working status of the chip (such as Vds voltage, open circuit status, short circuit status), and send it back to the host, and the host software automatically records and statistics the working conditions of the tested Mini LED driver chip, which helps the tester to record and discover problems and reasons in time; the power supply unit and level conversion unit provided inside it provide working voltages for each of the Mini LED driver chips and the FPGA master chip. For example, the power supply unit designs an adapter 5V input circuit, which mainly supplies power to the Mini LED driver chip, LED lamp beads and cement resistors, and then uses a level conversion unit (voltage regulator LDO) to step down and output 3.3V to supply power to the FPGA master chip; the multiple Mini LED driver chips are chips to be tested, and the cement resistors and multiple LED lamp beads are loads.

[0033] Please refer to Figure 3 , Figure 3 which is the connection circuit diagram of multiple Mini LED driver chips, multiple cement resistors and multiple LED lamp beads provided in the embodiment of the present invention. As Figure 3 shown, each Mini LED driver chip provided by the present invention can include an input terminal 1, output terminals 2 to 11. Among them, the input terminal 1 of the first Mini LED driver chip is connected to an external power supply, and its last output terminal (output terminal 11) is connected to the input terminal 1 of the second Mini LED driver chip, and the last output terminal (output terminal 11) of the second Mini LED driver chip is connected to the input terminal 1 of the third Mini LED driver chip and so on. One output terminal of each of the Mini LED driver chips, such as output terminal 5, output terminal 6 or output terminal 8, is respectively a channel, and each of these channels is respectively connected to a cement resistor and two LED lamp beads, and the cement resistor and the LED lamp beads are connected in parallel.

[0034] Working principle: During a certain test, according to the control instructions sent by the FPGA master chip, high-temperature and high-humidity tests are performed on the cement resistors and LED lamp beads connected to the channels selected for testing in this test. Since the LED lamp beads are greatly affected by the high-temperature and high-humidity environment, display problems will occur. Based on this display problem, the operating state of this channel of the Mini LED driver chip can be determined. If other problems occur to the LED lamp beads, such as the LED lamp beads going out, the cement resistor connected in parallel with it serves as a load to protect the Mini LED driver chip and conduct tests. Due to the high consistency and stability of the electrical characteristics of the cement resistor, when the LED lamp beads connected to a certain channel are affected by high temperature and high humidity and cannot accurately reflect the test results, the operating state of this channel is reflected by using this cement resistor, that is, the reliability of the high-temperature and high-humidity test of the Mini LED driver chip is improved.

[0035] It should be understood that the method content involved in the present invention, that is, the working principle, is all prior art.

[0036] In summary, as described above, the present invention provides a test system for Mini LED driver chips, which adds a multi-channel automatic feedback test circuit on the basis of the existing test circuit that can only test a single Mini LED driver chip. At the same time, considering the differences in test requirements of different customers in the test system, two load modes of cement resistors and LED lamp beads are set in parallel for each channel of each Mini LED driver chip to be tested in each automatic feedback test circuit. Thus, by using the cement resistor with high electrical characteristic consistency, when the LED lamp beads connected to a certain channel are affected by high temperature and high humidity and cannot accurately reflect the test results, the operating state of this channel is reflected by using this cement resistor, that is, the reliability of the high-temperature and high-humidity test of the Mini LED driver chip is improved.

[0037] Moreover, the present invention also adds an FPGA master control module to the test system, and then reads the internal state of each chip under test in real time through the UART bus, and records, statistics and gives early warning prompts for it, that is, an automatic feedback circuit mechanism is added to the test system. Thus, it is not necessary for testers to observe and register every day, and the test results of each Mini LED driver chip can be automatically obtained, recorded and displayed, that is, the automatic recording of test results is realized, manpower and material resources are saved, and the test efficiency is improved.

[0038] It should be noted that the above description is only a preferred embodiment of the present application and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the utility model involved in the present application is not limited to the technical solutions formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept of the utility model. For example, the technical solutions formed by the mutual replacement of the above features with the technical features (but not limited to) having similar functions disclosed in the present application.

[0039] Except for the technical features described in the specification, the remaining technical features are well-known to those skilled in the art. To highlight the innovative features of the present utility model, the remaining technical features will not be repeated here.

Claims

1. A test system for a Mini LED driving chip, characterized in that, Including: A host computer, an FPGA main control module, multiple Mini LED driver chips, multiple cement resistors, and multiple LED beads; Among them, the host computer, the FPGA main control module, and the multiple Mini LED driver chips are connected in sequence one by one, and each channel of each Mini LED driver chip is respectively connected in sequence with at least one of the cement resistors and at least one of the LED beads to form a multi-channel automatic feedback test circuit in which the cement resistors and the LED beads included in each channel are connected in parallel and then connected to each Mini LED driver chip. And in each of the automatic feedback test circuits, the host computer is communicatively connected to the FPGA main control module through 1-channel UART bus to send a test signal to the FPGA main control module or receive the operating status of each Mini LED driver chip that is real-time feedback by the FPGA main control module.

2. The test system for a Mini LED driving chip according to claim 1, wherein The FPGA main control module includes: an FPGA main control chip, a power supply unit, and a level conversion unit; The power supply unit is connected to the multiple Mini LED driver chips and the level conversion unit, and includes multiple first output terminals and one second output terminal that are the same in number as the Mini LED driver chips. Among them, one first output terminal is correspondingly connected to one Mini LED driver chip to provide a working voltage to the Mini LED driver chip, and the second output terminal is connected to the input terminal of the level conversion unit to step down the voltage of the power supply unit and provide a working voltage to the FPGA main control chip through the output terminal of the level conversion unit.

3. The test system for a Mini LED driving chip according to claim 2, wherein The model of the FPGA main control chip includes GW1N-UV9-QN48.

4. The test system for a Mini LED driving chip according to claim 2, wherein, The multiple Mini LED driver chips are connected in cascade; the first Mini LED driver chip among the multiple Mini LED driver chips is connected to the FPGA main control chip, and the first Mini LED driver chip is configured to receive all the control instructions corresponding to the Mini LED driver chips sent by the FPGA main control chip and send the control instructions corresponding to the other Mini LED driver chips to the next Mini LED driver chip.

5. The test system for a Mini LED driving chip according to claim 4, wherein, The multiple Mini LED driver chips are connected through a serial interface.

6. The test system for a MiniLED driving chip according to claim 1, 4 or 5, characterized in that The model of the Mini LED driver chip includes CX5831.

7. The test system for a MiniLED driving chip according to claim 1, characterized in that, Each Mini LED driver chip includes multiple channels, and the number of cement resistors and LED beads connected to each Mini LED driver chip is the same as the number of its channels.

8. The test system for the MiniLED driving chip according to claim 1, wherein, Each Mini LED driver chip includes multiple channels, the number of cement resistors connected to each Mini LED driver chip is the same as the number of its channels, and the number of LED beads connected to each Mini LED driver chip is N times the number of its channels, where N is greater than or equal to 2.

9. The test system for a MiniLED driving chip according to claim 1, wherein, The model of the LED lamp bead includes LW_M67C, and the cement resistor includes a color ring resistor with a resistance value of 1K ohm.

10. The test system for a MiniLED driving chip according to claim 2, wherein, The level conversion unit includes a voltage regulator power supply LDO, and the voltage regulator power supply LDO includes a power supply voltage regulation chip U7.

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