A multi-channel parallel test system for LCD liquid crystal screen

Abstract

The utility model relates to the field of liquid crystal display device test, specifically disclose a LCD liquid crystal screen's multichannel parallel test system, including main control board, screen interface board and power module, is equipped with main control MCU, image signal generation unit, communication interface and power management unit on main control board, screen interface board and main control board are detachably electrically connected, be equipped with a plurality of screen test channels on screen interface board, every screen test channel all includes the FPC connector and channel control chip for connecting LCD screen, and channel control chip is connected with main control MCU communication, the utility model has high density and high parallelism, and every screen test channel possesses independent power control and signal drive, can according to test production capacity demand flexible increase or reduce screen interface board quantity, promote screen test quantity, significantly improve test efficiency, reliability and intelligent level, low simultaneously artificial participation degree, reduce test cost, and test precision is high.

Description

Technical Field

[0001] This utility model relates to the field of liquid crystal display device testing, specifically a multi-channel parallel testing system for LCD screens. Background Technology

[0002] Currently, with the increasing market demand for LCD screens and customers placing greater emphasis on product quality, various specifications and models of LCD screens are emerging in the market. Factory testing has become an essential step, primarily including power-on and display function tests. The purpose of these tests is to eliminate early-failure products and ensure display quality. Current mainstream testing methods often employ a "one board, one screen" or "one board, a few screens" approach, resulting in low testing efficiency and requiring significant manual intervention for insertion, removal, observation, and recording. This leads to high labor costs and significant subjective errors, becoming a bottleneck for production capacity improvement. Existing multi-channel screen interface boards typically simply connect multiple screen interfaces in parallel to the same power and signal source. The testing of each screen cannot be independently controlled. If a serious fault such as a short circuit occurs in one channel, it directly affects the testing of other screens on the board, causing test interruption. All screens display the same content, making it impossible to perform tests requiring specific grayscale or color pattern verification, such as for point defects or line defects. Test coverage is low. Therefore, this application proposes a multi-channel parallel testing system for LCD screens to solve the above problems. Utility Model Content

[0003] To address the existing problems, this utility model provides a multi-channel parallel testing system for LCD screens, which can effectively solve the problems mentioned in the background art.

[0004] To solve the above problems, the present invention adopts the following technical solution: A multi-channel parallel testing system for LCD screens includes a main control board, at least one screen interface board, and a power supply module. The main control board is equipped with a main control MCU, an image signal generation unit, a communication interface, and a power management unit. The screen interface board is detachably electrically connected to the main control board and has multiple screen test channels. Each screen test channel includes an FPC connector for connecting to the LCD screen and a channel control chip. The channel control chip is communicatively connected to the main control MCU and is used to independently control the power supply and signal on / off of the corresponding FPC connector. The power supply module is connected to the system main control board and is used to power the entire system.

[0005] Preferably, the channel control chip is an intelligent switch chip that integrates a power MOSFET and a logic control circuit.

[0006] Preferably, the screen test channel further includes a current sampling circuit, which is used to monitor the working current flowing through the corresponding LCD screen in real time and feed the sampling data back to the main control MCU.

[0007] Preferably, the main control MCU stores system firmware, which is used to control the test process, analyze current data and manage communication. The system firmware is configured such that when the current value fed back by the current sampling circuit exceeds the preset upper and lower limit thresholds, the main control MCU determines that there is a channel fault and controls the channel control chip to cut off the power supply to the faulty channel, while continuing the test of other non-faulty channels.

[0008] Preferably, the image signal generation unit can generate a variety of programmable test pattern signals, including all-white, all-black, red, green, blue, grayscale patterns and checkerboard patterns.

[0009] Preferably, the communication interface is an Ethernet interface and / or a USB interface, used to connect to a host computer for issuing commands and transmitting data.

[0010] Preferably, the FPC connectors on the screen interface board adopt different specifications to adapt to LCD screens with different pin definitions and sizes.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model can realize the simultaneous testing of multiple LCD screens through multiple screen test channels on the screen interface board, which has high density and high parallelism. Each screen test channel has independent power control and signal drive. The failure of a single screen will be immediately isolated, ensuring the stable operation of the entire test system and that the testing of other screens is not affected. The number of screen interface boards can be flexibly increased or decreased according to the test capacity requirements, increasing the number of screens tested. This significantly improves the test efficiency, reliability and intelligence level. At the same time, the degree of manual intervention is low, the test cost is reduced, and the test accuracy is high. Attached Figure Description

[0012] Figure 1 A schematic diagram of the overall architecture of a multi-channel parallel testing system for an LCD screen; Figure 2 This is a schematic diagram showing the internal details of a multi-channel parallel testing system for an LCD screen.

[0013] In the diagram: 1. Main control board; 2. Screen interface board; 3. Power supply module; 4. Main control MCU; 5. Image signal generation unit; 6. Communication interface; 7. Power management unit; 8. Screen test channel; 9. FPC connector; 10. Channel control chip; 11. Current sampling circuit; 12. System firmware; 13. High-speed board-to-board connector; 14. Host computer; 15. LCD screen. Detailed Implementation

[0014] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0015] Combination Figures 1 to 2 This embodiment provides a multi-channel parallel testing system for an LCD screen, comprising a main control board 1, at least one screen interface board 2, and a power supply module 3. The main control board 1 is equipped with a main control MCU 4, an image signal generation unit 5, a communication interface 6, and a power management unit 7. The screen interface board 2 is detachably electrically connected to the main control board 1 and has multiple screen test channels 8. Each screen test channel 8 includes an FPC connector 9 for connecting to an LCD screen 15, a channel control chip 10, and a current sampling circuit 11. The channel control chip 10 is communicatively connected to the main control MCU 4 and is used to independently control the power supply and signal on / off of the corresponding FPC connector 9. The current sampling circuit 11 is used to monitor the working current flowing through the corresponding LCD screen 15 in real time and feed the sampled data back to the main control MCU 4. The power supply module 3 is connected to the main control board 1 and is used to power the entire system. The power supply module 3 is a switching power supply, with its input end connected to external AC power and its output end connected to the power management unit 7 of the main control board 1, providing power to the entire system and the LCD screen 15 under test.

[0016] In this embodiment, the main control MCU4 stores system firmware 12. System firmware 12 is used to control the test process, analyze current data and manage communication. System firmware 12 is configured so that when the current value fed back by the current sampling circuit 11 exceeds the preset upper and lower limit thresholds, the main control MCU4 determines that the channel is faulty and controls the channel control chip 10 to cut off the power supply of the faulty channel, while continuing the test of other non-faulty channels. System firmware 12 supports remote firmware upgrade and test parameter configuration through the host computer 14.

[0017] Specifically, the main control board 1 is based on a high-performance ARM Cortex-M series main control MCU4, with an external Flash memory for storing system firmware 12 and test data. The image signal generation unit 5 is either a dedicated video processing chip or directly used by the LCD interface of the main control MCU4 to generate RGB test signals. The image signal generation unit 5 can generate a variety of programmable test pattern signals, including all-white, all-black, red, green, blue, grayscale patterns and checkerboard patterns. The power management unit 7 receives the 12V DC input from the power supply module 3, converts it into the voltage required by the system such as 5V and 3.3V, and provides a power bus for the screen interface board 2.

[0018] The screen interface board 2 is connected to the main control board 1 via a high-speed board-to-board connector 13. The channel control chip 10 is an analog switch or a smart power switch, controlled by the I / O of the main control MCU4. The channel control chip 10 is a smart switch chip that integrates power MOSFETs and logic control circuits, used to switch the power supply and signal of the screen in that channel. The current sampling circuit 11 includes a sampling resistor and an operational amplifier. The sampling resistor is connected in series in the screen power supply circuit. The operational amplifier amplifies the voltage difference across the sampling resistor and outputs it to the ADC input pin of the main control MCU4. The current sampling circuit 11, composed of a high-precision current sampling resistor and an operational amplifier, converts the current signal into a voltage signal and feeds it back to the ADC pin of the main control MCU4.

[0019] Communication interface 6 uses Ethernet and / or USB interfaces to connect to host computer 14, and sends commands and transmits data through host computer 14. During the test, the main control MCU4 continuously records the current-time curve data of all channels and uploads it to host computer 14 through communication interface 6.

[0020] The FPC connectors 9 on the screen interface board 2 adopt different specifications to adapt to LCD screens 15 with different pin definitions and sizes. The main control board 1 can connect to and control multiple screen interface boards 2 at the same time to expand the number of screen test channels 8.

[0021] The working principle of this utility model is as follows: The host computer 14 issues test tasks, and the main control MCU4 opens the screen test channels 8 one by one or in groups in sequence, and outputs test patterns (such as all white, all black, three primary colors, grayscale, etc.) to each LCD screen 15. The current sampling circuit 11 monitors the current of each channel in real time. If the current of a certain channel is abnormal (such as too large indicating a short circuit, or too small indicating an open circuit), the main control MCU4 immediately records the channel ID and fault information, and closes the channel. At the same time, it continues to test other channels. After all tests are completed, a test report is generated and uploaded to the host computer 14. It can automatically isolate faulty screens, ensure the overall stability of the system, support efficient and automated parallel testing of hundreds or thousands of screens, and significantly improve test efficiency, reliability and intelligence level.

[0022] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0023] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-channel parallel testing system for an LCD screen, comprising a main control board, at least one screen interface board, and a power supply module, characterized in that, The main control board is equipped with a main control MCU, an image signal generation unit, a communication interface, and a power management unit. The screen interface board is detachably electrically connected to the main control board. The screen interface board is equipped with multiple screen test channels. Each screen test channel includes an FPC connector for connecting to an LCD screen and a channel control chip. The channel control chip is communicatively connected to the main control MCU and is used to independently control the power supply and signal on / off of the corresponding FPC connector. The power supply module is connected to the main control board and is used to power the entire system.

2. The multi-channel parallel testing system for an LCD screen according to claim 1, characterized in that, The channel control chip is an intelligent switch chip that integrates power MOSFETs and logic control circuits.

3. The multi-channel parallel testing system for an LCD screen according to claim 1, characterized in that, The screen test channel also includes a current sampling circuit, which is used to monitor the working current flowing through the corresponding LCD screen in real time and feed the sampling data back to the main control MCU.

4. The multi-channel parallel testing system for an LCD screen according to claim 3, characterized in that, The main control MCU stores system firmware, which is used to control the test process, analyze current data and manage communication. The system firmware is configured so that when the current value fed back by the current sampling circuit exceeds the preset upper and lower limit thresholds, the main control MCU determines that the channel is faulty and controls the channel control chip to cut off the power supply to the faulty channel, while continuing the test of other non-faulty channels.

5. The multi-channel parallel testing system for an LCD screen according to claim 1, characterized in that, The image signal generation unit can generate a variety of programmable test pattern signals, including all-white, all-black, red, green, blue, grayscale patterns and checkerboard patterns.

6. The multi-channel parallel testing system for an LCD screen according to claim 1, characterized in that, The communication interface uses an Ethernet interface and / or a USB interface to connect to a host computer, through which commands are sent and data is transmitted.

7. The multi-channel parallel testing system for an LCD screen according to claim 1, characterized in that, The FPC connectors on the screen interface board adopt different specifications to adapt to LCD screens with different pin definitions and sizes.

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