Automatic test method for Mini LED light bar

Abstract

The invention discloses an automatic test method for a Mini LED light bar, and the method comprises the following steps: S1.1, a single-chip microcomputer calculation unit circuit emits a PWM data signal to lighten each partition and adjust the brightness of each LED, after a driving IC receives a command, the driving IC opens output channels one by one, collects the voltage drop voltage and current of each channel, and feeds back the voltage drop voltage and current to an IO port of a single-chip microcomputer through a data line; s1.2, the single-chip microcomputer collects current and voltage data, fed back from the light bar, of each LED light point; and S1.3, according to the current and voltage data acquired in the step S1.2, if the current is very low and the voltage is very high, judging whether each dimming subarea has an open circuit, and if the current is very high and the voltage is very low, judging whether each dimming subarea has faults such as a short circuit and uneven brightness. The technical problems of energy waste, high power consumption and low contrast caused by the fact that brightness adjustment is realized by changing the transmittance of the panel when pictures with different brightness need to be displayed can be solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of LED lamp detection methods, and specifically relates to an automated testing method for MiniLED light strips. Background Art

[0002] LED light strips are LEDs assembled on a strip-shaped FPC or PCB hard board. They are named because of their shape like a strip. Because of their long service life, which is generally 80,000 to 100,000 hours, and their energy saving and environmental protection, they are gradually emerging in various decoration industries. Flexible LED light strips use FPC as the assembly circuit board and high-brightness LEDs packaged with SMD as the light source. Every 3 lights are a unit, and every 50 cm is a large length unit. The thickness of this product is only the thickness of a coin, and it does not take up space. The soft LED light strip can be cut or extended at will without affecting the light emission.

[0003] LED hard light strips use PCB hard boards as assembly circuit boards. LEDs are assembled using SMD LEDs or DIP LEDs. Different components are used depending on the needs. The advantage of hard light strips is that they are easier to fix, and are more convenient to process and install; the disadvantage is that they cannot be bent at will and are not suitable for irregular places.

[0004] Traditional LCD monitors usually use direct-down and side LED light strips. The backlight strips are in the brightest state when the LCD TV is working, and the brightness remains unchanged. When different brightness images need to be displayed, the brightness is adjusted by changing the panel transmittance instead of adjusting the brightness of the light strip. This results in energy waste, high power consumption, and low contrast. Summary of the invention

[0005] The purpose of the present invention is to provide an automated testing method for MiniLED light strips to solve the technical problem that when different brightness images need to be displayed, brightness adjustment is achieved by changing the panel transmittance, resulting in energy waste, high power consumption and low contrast.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] An automated testing method for MiniLED light strips, comprising the following steps:

[0008] S1.1, the MCU calculation unit circuit sends out PWM data signals to light up each partition and adjust the brightness of each LED. After receiving the command, the driver IC opens the output channels one by one and collects the voltage drop and current of each channel, and feeds back to the MCU IO port through the data line;

[0009] S1.2, the microcontroller will collect the current and voltage data of each LED light point fed back from the light bar;

[0010] S1.3. According to the current and voltage data collected in step S1.2, if the current is very small and the voltage is very high, determine whether there is a circuit breaker in each dimming zone; if the current is very large and the voltage is very small, determine whether there is a short circuit or uneven brightness in each dimming zone, and connect the status of the dimming zone to the computer via RS-232 to display the result.

[0011] Furthermore, each channel of the driver IC adopts constant current control, and the LED light point adopts blue light LED.

[0012] Furthermore, the single-chip computing unit circuit includes a light-emitting diode D1 connected to a power supply voltage, the light-emitting diodes are distributed in a matrix, and the cathodes of the light-emitting diodes D1 are connected to the output pins of the driver ICs one by one, one end of the driver ICs is connected to the power supply voltage and grounded, and the driver ICs are connected in series in a hand-in-hand manner;

[0013] Among them, the driving ICs at the head and tail are connected to the input and output interfaces of the single-chip microcomputer through data lines.

[0014] Furthermore, the model of the driver IC is XP7008H.

[0015] Furthermore, it also includes a suction cup mechanism connected to the light bar, the suction cup mechanism includes symmetrically arranged vacuum suction cups placed on the side wall of the display, one end of the light board on the light bar is connected to the display by locking and fixing it with a positioning bolt, and the other end is connected to the suction port on the vacuum suction cup.

[0016] Furthermore, the light bar is provided with a port connected to a data line, and the light board is connected to a card slot disposed on the inner wall of the display in the length direction.

[0017] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0018] (1) The Mini Led backlight strip adopts the method of dynamic dimming in different zones to achieve high contrast, low power consumption and improve the display effect. Two data lines are set in this scheme. One data line is connected to a single pin of the first driver IC of the light strip, and the other data line is connected to the last driver IC. Each zone requires a driver IC, and the driver ICs of the zones are connected hand in hand. The more zones the light strip has, the more driver ICs it has. For multi-zone Mini Led light strips, fast and automatic testing can be achieved. The single-chip microcomputer reads the working voltage and current of each LED in each zone at one time for calculation and analysis, and then connects to the computer through RS-232 to display the results, thereby timely reflecting the operating status of each light point on the light strip. The detection accuracy is high, the operation is convenient, and the applicability is strong.

[0019] (2) The setting of the suction cup mechanism can effectively install and fix the light strip. The light board on the light strip is first embedded and connected to the inner wall of the display, and then the light board can be further fixed by the positioning bolt and the vacuum suction cup, thereby effectively increasing the stability of the structural connection and ensuring the normal operation of the light strip, thereby increasing the service life of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a flow chart of a method for automatic testing of MiniLED light strips according to the present invention;

[0022] Figure 2 It is a structural block diagram of the MCU computing unit of the present invention;

[0023] Figure 3 It is a schematic diagram of the single chip computing unit circuit of the present invention;

[0024] Figure 4 It is a structural schematic diagram of the suction cup mechanism of the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Reference Manual Attached Figure 1-4 , a method for automated testing of MiniLED light strips, comprising the following steps:

[0027] S1.1, the MCU calculation unit circuit sends out PWM data signals to light up each partition and adjust the brightness of each LED. After receiving the command, the driver IC opens the output channels one by one and collects the voltage drop and current of each channel, and feeds back to the MCU IO port through the data line;

[0028] S1.2, the microcontroller will collect the current and voltage data of each LED light point fed back from the light bar;

[0029] S1.3. According to the current and voltage data collected in step S1.2, if the current is very small and the voltage is very high, determine whether there is a circuit breaker in each dimming zone; if the current is very large and the voltage is very small, determine whether there is a short circuit or uneven brightness in each dimming zone, and connect the status of the dimming zone to the computer via RS-232 to display the result.

[0030] PWM data signal is a periodic digital signal, namely pulse width modulation. It controls or simulates the signal by changing the width of the pulse signal. Each pulse consists of a high level and a low level, and the ratio of the pulse width to the entire period is called the duty cycle. By adjusting the duty cycle, the PWM signal can achieve approximate or precise control of the analog signal. PWM outputs a digital signal, and the high and low levels of the signal are controlled by the width and period of the pulse.

[0031] This technology converts analog signals into digital signals, thereby achieving precise control of the device. PWM technology has many advantages, including simplified circuit design, improved system reliability and easy microprocessor control.

[0032] RS-232 is one of the commonly used serial communication interface standards. The RS-232 bus specifies 25 lines, including two signal channels, namely the first channel and the second channel. Full-duplex communication can be achieved using the RS-232 bus. The main channel is usually used, while the secondary channel is rarely used. In general applications, full-duplex communication can be achieved using 3 to 9 signal lines. Using three signal lines, the receiving line, the transmitting line and the signal line, a simple full-duplex communication process can be achieved.

[0033] RS-232 has the characteristics of flexible baud rate selection, long transmission distance and few signal lines.

[0034] Specifically, each channel of the driver IC adopts constant current control, and the LED lamp point adopts blue light LED, where voltage drop = power supply voltage - Vf*M, where Vf is the driving voltage of a single lamp bead, and M is the number of lamp beads in series. Through the above calculation formula, the current and voltage displayed by the corresponding lamp bead on the light bar can be observed in time, and the circuit status of each dimming zone can be seen in time through the voltage drop.

[0035] The single-chip computing unit circuit includes a light-emitting diode D1 connected to the power supply voltage. The light-emitting diodes are distributed in a matrix, and the cathodes of the light-emitting diodes D1 are connected to the output pins of the driver IC one by one. One end of the driver IC is connected to the power supply voltage and grounded. The driver ICs are connected in series hand in hand. The first and last driver ICs are connected to the input and output interface of the single-chip computer through data lines. The model of the driver IC is XP7008H.

[0036] In the above circuit, the working status of the light-emitting diode D1 on each partition light strip can be directly fed back and displayed. By using the power supply voltage inside the driver IC and the external power supply voltage in coordination, the normal use of the single-chip computer calculation unit circuit can be effectively guaranteed. At the same time, the power supply voltage plays the role of a backup internal power supply, thereby improving the safety of the device.

[0037] Existing LEDs all use multi-cascade packaging. One LED package has multiple PN junctions. When a bad pixel appears in a certain partition, detection is also a difficult problem to solve. The detection methods include special analyzers and manual visual inspection. Special instruments have many configurations, high costs, strong professionalism, and high requirements for users. The manual visual inspection method has obvious disadvantages. It requires some experience from the inspectors, has a large workload, and is prone to visual fatigue, resulting in missed inspections and misjudgments, which ultimately leads to low efficiency and reduced product quality.

[0038] The technical solution of the present invention is that the Mini Led backlight strip adopts a partition dynamic dimming method to achieve high contrast, low power consumption and improve display effect. Two data lines are set in the solution, one data line is connected to a single pin of the first driver IC of the light strip, and the other data line is connected to the last-level driver IC. Each partition requires a driver IC, and the driver ICs of the partitions are connected hand in hand. The more partitions the light strip has, the more driver ICs it has. For the multi-partition Mini Led light strip, fast and automatic testing can be achieved. The single-chip microcomputer reads the working voltage and current of each LED in each partition at one time for calculation and analysis, and then connects to the computer through RS-232 to display the results, thereby timely reflecting the operating status of each lamp point on the light strip. The detection accuracy is high, the operation is convenient, and the applicability is strong. Whether the lamp body at different positions is working normally can be judged and detected in time.

[0039] The technical solution of the present invention is essentially to detect the state of the LED light after the light bar is lit by a single chip microcomputer, detect whether the light bar is normal, and report the detection result through a computer display.

[0040] Specifically, an automated testing method for a MiniLED light bar also includes a suction cup mechanism 1 connected to the light bar, the suction cup mechanism 1 includes a symmetrically arranged vacuum suction cup 2 placed on the side wall of a display, one end of a light board 3 on the light bar is connected to the display by being locked and fixed by a positioning bolt, and the other end is connected to a suction port on the vacuum suction cup 2, a port connected to a data cable is provided on the light bar, and a card slot placed on the inner wall of the display is connected to the light board 3 in the length direction.

[0041] By extension, the suction cup mechanism 1 is a fixed structure for installing the light panel 3 inside the display, and can also be connected by locking and fixing with a stop pin. As the stop pin assembly is a conventional technical means for those skilled in the art, it will not be described in detail here, but it does not affect the implementation of the technical solution of the present invention.

[0042] The setting of the suction cup mechanism 1 can effectively install and fix the light strip. The light board 3 on the light strip is first embedded and connected to the inner wall of the display, and then the light board can be further fixed by the positioning bolt and the vacuum suction cup 2, thereby effectively increasing the stability of the structural connection and ensuring the normal operation of the light strip, thereby improving the service life of the device.

[0043] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0044] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for automated testing of MiniLED light strips, characterized in that: The steps include: S1.1, the MCU calculation unit circuit sends out PWM data signals to light up each partition and adjust the brightness of each LED. After receiving the command, the driver IC opens the output channels one by one and collects the voltage drop and current of each channel, and feeds back to the MCU IO port through the data line; S1.2, the microcontroller will collect the current and voltage data of each LED light point fed back from the light bar; S1.

3. According to the current and voltage data collected in step S1.2, if the current is very small and the voltage is very high, determine whether there is a short circuit in each dimming zone; if the current is very large and the voltage is very small, determine whether there is a short circuit and uneven brightness in each dimming zone, and connect the status of the dimming zone to the computer via RS-232 to display the results.

2. The method for automatic testing of MiniLED light strips according to claim 1, characterized in that: Each channel of the driver IC adopts constant current control, and the LED light point adopts blue light LED.

3. The method for automatic testing of MiniLED light strips according to claim 1, characterized in that: The single-chip computing unit circuit includes a light-emitting diode D1 connected to a power supply voltage, the light-emitting diodes are distributed in a matrix, and the cathodes of the light-emitting diodes D1 are connected to the output pins of the driver ICs one by one, one end of the driver ICs is connected to the power supply voltage and grounded, and the driver ICs are connected in series in a hand-in-hand manner; Among them, the driving ICs at the head and tail are connected to the input and output interfaces of the single-chip microcomputer through data lines.

4. The method for automated testing of MiniLED light strips according to claim 3, characterized in that: The model of the driver IC is XP7008H.

5. The method for automatic testing of MiniLED light strips according to claim 1, characterized in that: It also includes a suction cup mechanism (1) connected to the light bar, the suction cup mechanism (1) includes a symmetrically arranged vacuum suction cup (2) placed on the side wall of the display, one end of the light board (3) on the light bar is connected to the display by locking and fixing with a positioning bolt, and the other end is connected to the suction port on the vacuum suction cup (2).

6. The method for automatic testing of MiniLED light strips according to claim 5, characterized in that: The light bar is provided with a port connected to a data line, and the light board (3) is connected to a card slot disposed on the inner wall of the display in the length direction.

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