CN210136709U - Backlight testing device and display - Google Patents

Abstract

The utility model discloses a testing arrangement and display are shaded, including microprocessor, a plurality of LED drivers and at least one first string mouth extension chip, a plurality of LED drivers are connected with microprocessor in order to receive the drive signal that is shaded that microprocessor provided, and according to the luminance in a poor light of a plurality of subregion in a poor light of drive signal control in a poor light, every first string mouth extension chip includes first interface and a plurality of second interface, first interface is connected with the microprocessor electricity, every second interface is connected with the state pin electricity of the LED driver that corresponds, first string mouth extension chip is used for providing the state information of every LED driver to microprocessor, microprocessor's IO resource has been saved greatly, be favorable to reducing test cost, improve efficiency of software testing.

Description

Backlight testing device and display

Technical Field

The utility model relates to a liquid crystal display technology field, more specifically relate to a testing arrangement and display are shaded.

Background

The display device is a display device that changes the light transmittance of a light source by using a phenomenon that the alignment direction of liquid crystal molecules is changed by an electric field. Displays have been widely used in mobile terminals such as mobile phones and large-sized display panels such as flat panel televisions due to advantages of good display quality, small volume, and low power consumption.

In the display, the luminance of each pixel is determined by the luminance of the backlight unit and the light transmittance of the liquid crystal. Existing displays therefore typically employ backlight adjustment for the purpose of increasing contrast and reducing power consumption. Backlight adjustment is a technique of controlling backlight brightness and compensating data by analyzing an input image and adjusting a dimming value based on the analysis.

The Local Dimming technique (Local Dimming) is to divide the display into a plurality of backlight partitions based on a backlight unit, and then automatically control the brightness of each backlight partition, thereby greatly reducing the power consumption, improving the contrast of the display image, increasing the gray scale, reducing the ghost and improving the display image quality of the display.

When adjusting the backlight area, a CPU (Central Processing Unit) is needed to analyze the input image data to obtain the brightness of each backlight partition, and then the brightness of each backlight partition is controlled according to the calculation result, which is substantially to adjust the brightness of the LED of each backlight partition by controlling a Light Emitting Diode (LED) driving chip.

In order to ensure the normal operation of the LED driving chips of each backlight partition, a microprocessor is required to test a plurality of LED driving chips on a display to obtain status information, power consumption information, and the like of each LED driving chip. Each LED driving chip has a status pin for indicating whether the chip is working normally, and in order to accurately locate the working abnormality of the driving chips during backlight test, the status pins of all the driving chips need to be connected to the microprocessor, so that each LED driving chip needs to occupy an I/O (Input/Output) interface of the microprocessor. With the increase of the number of backlight partitions, the number of required LED driving chips is increased, the requirement on the number of I/Os of a microprocessor is increased, the test cost of the display is greatly increased, and the test efficiency is reduced.

SUMMERY OF THE UTILITY MODEL

In view of this, an object of the present invention is to provide a backlight testing device and a display, which greatly save the I/O resources of the microprocessor, reduce the testing cost of the display, and improve the testing efficiency on the basis of not changing the original design.

According to the utility model discloses an aspect provides a testing arrangement is shaded, include: a microprocessor for providing a backlight driving signal; the LED drivers are connected with the microprocessor to receive the backlight driving signals and control the backlight brightness of the backlight partitions according to the backlight driving signals; and at least one first serial port expansion chip, wherein each first serial port expansion chip comprises a first interface and a plurality of second interfaces, the first interface is electrically connected with the microprocessor, and each second interface is electrically connected with a corresponding status pin of the LED driver, and the first serial port expansion chip is used for providing status information of each LED driver for the microprocessor.

Preferably, the backlight testing apparatus further comprises: a dial switch; and the dial switch is electrically connected with the microprocessor through the second serial port expansion chip.

Preferably, the backlight testing device further comprises a signal processor electrically connected to the microprocessor, wherein the signal processor receives an input image signal, analyzes the input image signal based on the plurality of backlight partitions, provides the microprocessor with a dimming value of each backlight partition, and obtains the backlight driving signal according to the dimming value.

Preferably, the backlight testing device further comprises a power consumption detecting unit connected between the microprocessor and the plurality of LED drivers, for providing the microprocessor with power consumption information of the plurality of LED drivers.

Preferably, the microprocessor further comprises a third interface electrically connected to the signal processor, the microprocessor providing initialization data to the signal processor via the third interface.

Preferably, the microprocessor further comprises a memory for storing the state information and the power consumption information.

Preferably, the microprocessor further comprises a fourth interface, the fourth interface is connected with an upper computer, and the upper computer is used for displaying the state information and the power consumption information of the LED driver and debugging the microprocessor through the fourth interface.

Preferably, the signal processor is a timing controller.

Preferably, the microprocessor is an ARM processor.

According to another aspect of the present invention, there is provided a display device, including the above backlight testing device.

The utility model provides a testing arrangement and display in a poor light has following beneficial effect.

The backlight testing device comprises a microprocessor and a plurality of LED drivers, wherein the LED drivers are connected with the microprocessor to receive backlight driving signals provided by the microprocessor and control the backlight brightness of a plurality of backlight partitions according to the backlight driving signals. The backlight testing device further comprises at least one first serial port expansion chip, each first serial port expansion chip comprises a first interface and a plurality of second interfaces, the first interfaces are electrically connected with the microprocessor, each second interface is electrically connected with a status pin of the corresponding LED driver, and the first serial port expansion chips are used for providing status information of each LED driver for the microprocessor. In the utility model, the electrical connection between the microprocessor and the plurality of LED drivers is realized through the first serial port extension chip, the I/O resource of the microprocessor is greatly saved on the basis of not changing the original circuit structure, and the test cost is favorably reduced; meanwhile, the subsequent backlight power consumption, brightness and other functions can be tested more conveniently, and the testing efficiency is improved.

In a preferred embodiment, the backlight testing device further comprises a dial switch, and the tester adjusts the backlight current value through the dial switch during the backlight test. The current value can be visually displayed through the dial switch, so that a display screen for displaying the current backlight current is saved, the test cost is further saved, and the test efficiency is improved.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings.

Fig. 1 shows a schematic structural diagram of a display according to an embodiment of the present invention;

fig. 2 shows a schematic structural diagram of a backlight testing device according to an embodiment of the present invention.

Detailed Description

The invention will be described in more detail below with reference to the accompanying drawings. Like elements in the various figures are denoted by like reference numerals. For purposes of clarity, the various features in the drawings are not necessarily drawn to scale. Moreover, certain well-known elements may not be shown in the figures.

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Fig. 1 shows a schematic structural diagram of a display according to an embodiment of the present invention. As shown in fig. 1, the display 100 includes a display panel 110, a gate driver 120, a source driver 130, a backlight unit 140, and a backlight testing apparatus 150.

The display panel 110 includes a plurality of gate scan lines G1-Gm and a plurality of source data lines S1-Sn crossing each other, and pixel cells including thin film transistors and pixel electrodes are disposed at the crossing positions of the two. The liquid crystal layer is included between the pixel electrode and the common electrode, and can be equivalent to a liquid crystal capacitor. To hold the voltage between update periods of the pixel, the liquid crystal capacitance may store the capacitance in parallel for a longer hold time.

The gate driver 120 is connected to the plurality of gate scan lines for providing a gate voltage to sequentially scan the plurality of gate scan lines in each frame period to gate the corresponding thin film transistors. The source driver 130 is connected to a plurality of source data lines for applying voltages corresponding to gray scales to the liquid crystal capacitors via the source data lines, thereby changing the deflection of the liquid crystal molecules.

The backlight unit 140 includes a plurality of backlight sources for providing backlight to the display panel 110. The multiple backlights may consist of single or multiple point light sources. Illustratively, the backlight source is composed of a plurality of LEDs (Light Emitting diodes) for providing backlight to the display panel 110. In one embodiment, the display 100 employs a direct type backlight, and the backlight unit 140 is located at one side of the lower surface of the display panel 110, and the backlight passes through the display panel 110 to the eyes of the viewer when the display is in use. In another embodiment, the display 100 employs a side-in type backlight, and the backlight unit 140 is located at the upper and lower sides or left and right sides of the display panel 110, and the light path of the backlight is changed by the light guide plate to pass through the display panel 110 to the eyes of the viewer.

The backlight test apparatus 150 is used to control the brightness of a plurality of backlights in the backlight unit 140 according to an input image signal at the time of backlight test. Illustratively, the display panel 110 includes a plurality of backlight partitions divided on the basis of the backlight unit 140, and the backlight test device 150 drives the luminance of the backlight source in the backlight unit 140 in units of the plurality of backlight partitions.

Fig. 2 shows a schematic structural diagram of a backlight testing device according to an embodiment of the present invention. Referring to fig. 2, the backlight testing apparatus includes a signal processor 151, a microprocessor 152, and a backlight driver 153.

The signal processor 151 obtains a dimming value of each backlight partition, which individually drives the luminance of the backlight corresponding to each backlight partition, according to the gray-scale luminance of the input image signal. The backlight source in each backlight partition may be composed of a single or multiple point light sources, such as LEDs, the brightness of the backlight source in each backlight partition is controlled independently, and the brightness of the backlight source in the backlight partition is determined by the gray-scale brightness of the display area corresponding to the backlight partition.

For example, the signal processor 151 analyzes the input image signal on a block basis through an internal algorithm, analyzes a gray-scale mean value of each backlight partition, and matches the luminance of the backlight source of the corresponding backlight partition to obtain a dimming value of each backlight partition.

For example, the signal processor 151 receives an input image signal, separately collects gray-scale luminance values of image partitions corresponding to respective backlight partitions in the input image signal, which may be an average value or an average weight value, according to a predetermined image partition rule, and then converts the gray-scale luminance values into corresponding dimming values. For example, a backlight partition may include a single or a plurality of point light sources, such as LEDs, and the luminance of the point light sources driving the backlight partition is higher if the luminance of the image frame of the backlight partition is higher, and the luminance of the point light sources driving the backlight partition is lower if the luminance of the image frame in the backlight partition is lower.

On the other hand, the signal processor 151 also format-converts the input image signal in accordance with the specification of a predetermined display panel, and supplies various timing signals and gray-scale driving signals to the gate driver 120 and the source driver 130.

The microprocessor 152 is configured to provide a backlight driving signal to the backlight driver 153 according to the dimming value, and the backlight driver 153 controls the brightness of the backlight source of the plurality of backlight partitions according to the backlight driving signal. Illustratively, the microprocessor 152 outputs a corresponding Pulse Width Modulation (PWM) signal to the backlight driver 153 according to the dimming value, and the backlight driver 153 supplies a corresponding current to the backlight unit 140 according to the PWM signal to adjust the brightness of the backlight source corresponding to the backlight partition.

The backlight driver 153 is composed of a plurality of LED drivers (e.g., LED driver 1-LED driver 32) cascaded. Illustratively, the LED drivers 1 to 32 correspond to a plurality of backlight partitions one to one, and control the brightness of the backlight source of the corresponding backlight partition according to the received backlight driving signal.

The backlight testing apparatus further includes a plurality of first serial port expansion chips 155 (e.g., labeled IC1(Integrated Circuit) and IC2 in the figure), each first serial port expansion chip 155 including a first interface (e.g., labeled SPI3 and SPI4 in the figure) electrically connected to the microprocessor 152 and a plurality of second interfaces (e.g., labeled GPA0-GPA7 and GPB0-GPB7 in the figure), each of which is electrically connected to a status pin of a corresponding LED driver (e.g., LED driver 1-LED driver 32). Wherein, the first serial port expansion chip 155 is used for providing status information of each of the LED drivers to the microprocessor 152.

Further, the microprocessor 152 obtains the level status of the status pins of the LED drivers 1-32 via the first serial port expansion chip 155, and determines whether the driver is working normally according to the level status of the status pins of the LED drivers, for example, when the status pin of the LED driver is high level, it indicates that the driver is working normally, and when the status pin of the LED driver is low level, it indicates that the driver is working abnormally.

It should be noted that the numbers of the LED driver and the first serial port extension chip in fig. 2 are only exemplary, and do not limit the backlight testing apparatus of the present embodiment, and those skilled in the art may select the numbers of the LED driver and the first serial port extension chip according to specific situations. Furthermore, in this embodiment, there is a corresponding relationship between the number of the first serial port extension chips and the number of the LED drivers, and the number of the first serial port extension chips depends on the number of the LED drivers and the number of channels of each first serial port extension chip. For example, for a conventional 16-channel serial expansion chip (each chip can be connected with 16 LED drivers), when the number of LED drivers is 32, 2 first serial expansion chips are required; when the number of the LED drivers is 48, 3 first serial port extension chips are required; when the number of LED drivers is 56, 4 first serial port extension chips are required, and so on.

The backlight testing apparatus further includes a DIP Switch (DIP Switch)156, which is also called a toggle Switch, an address Switch, a digital Switch, etc., and is an address Switch for operation control, and adopts the binary coding principle of 0/1. The tester is used to adjust the backlight current value via the dial switch 156 during the backlight test. Since the current value can be visually displayed through the dial switch 156, a display screen for displaying the current backlight current is saved, and the test cost is further saved.

Since the dial switch includes a plurality of keys and pins corresponding to the keys, when the dial switches 156 are connected to the microprocessor 152, a large amount of I/O resources of the microprocessor 152 are occupied, which results in waste of I/O resources of the microprocessor 152. Therefore, the backlight testing device further comprises at least one second serial port expansion chip 157 (for example, as shown by label IC3 in the figure), and the dial switch 156 is electrically connected with the microprocessor 152 via the second serial port expansion chip 157. Similarly, the second serial port expansion chip 157 also includes a first interface (for example, as shown by the mark SPI5 in the figure) and a plurality of second interfaces (for example, as shown by the marks GPA0-GPA7 and GPB0-GPB7 in the figure), where the first interface is electrically connected to the microprocessor 152, and each of the second interfaces is correspondingly connected to a pin of the dial switch 156, so that waste of I/O resources on the microprocessor 152 is reduced.

Further, the backlight testing apparatus of this embodiment further includes a power consumption detecting unit 158, where the power consumption detecting unit 158 is connected between the microprocessor 152 and the LED drivers 1 to 32, and is configured to provide power consumption information such as current and voltage when the LED drivers 1 to 32 drive the backlight to the microprocessor.

Further, the microprocessor 152 is a Micro Controller Unit (MCU), such as a von neumann or harvard architecture RISC CPU, including but not limited to ARM, MIPS, OPEN RISC, etc., preferably ARM; or a DSP, etc.

As a non-limiting example, the signal processor 151 is implemented by a Timing Controller (TCON). The time sequence controller converts an input image signal (the input image signal comprises three signals of an RGB data signal, a clock signal and a control signal) from an external circuit into an LVDS signal capable of driving the liquid crystal screen after logic processing, and then directly sends the LVDS signal to a gate driver and a source driver of the liquid crystal screen.

The time sequence controller is also used for analyzing the input image signals on the basis of the backlight partitions through an internal algorithm, analyzing the gray-scale mean value of each backlight partition, matching the backlight brightness of the backlight source of the corresponding backlight partition, and obtaining the dimming value of each backlight partition.

The microprocessor 152 is implemented by an ARM processor, and the microprocessor 152 is connected to the timing controller, the plurality of LED drivers, the first Serial port expansion chip 155, and the second Serial port expansion chip 157 by an SPI (Serial peripheral interface).

Further, the ARM processor provides initialization data to the time schedule controller through a third interface. For example, the ARM processor and the timing controller transmit data through an I2C bus, and the data and the algorithm program inside the timing controller are updated in the debugging phase.

Further, data is transmitted between the ARM processor and the power consumption detection unit 158 through the I2C bus, and power consumption information such as current, voltage, etc. of the backlight driving of the plurality of LED drivers is obtained in the backlight testing stage.

Further, the microprocessor 152 further includes a memory 154, and the memory 154 is used for storing the state information and the power consumption information obtained by the microprocessor 152. Illustratively, the memory 154 is implemented by a flash memory (FlashMemory) inside the ARM processor, and a part of the flash memory inside the ARM processor may be opened up to simulate an EEPROM for storing the state information and the power consumption information.

Further, the microprocessor 152 further includes a fourth interface, and the fourth interface is connected to an upper computer (for example, a PC) for displaying status information and power consumption information of the plurality of LED drivers. For example, the upper computer receives and displays the status information and the power consumption information of the plurality of LED drivers provided by the ARM processor through a USB (Universal Serial Bus).

The operation principle of the backlight testing device of the present embodiment will be briefly described with reference to fig. 2.

The microprocessor 152 performs SPI communication interface detection to detect the integrity of the connections between the various devices in the backlight test apparatus. After the communication link detection of the backlight test device is complete, the individual LED drivers are initialized by the microprocessor 152 via the SPI interface. The microprocessor 152 then cycles through the status pins of the various LED drivers. For example, the microprocessor 152 receives the level state of the status pin of each LED driver through the plurality of first serial port extension chips, and determines the operating state of each LED driver according to the level state of the status pin of the LED driver. If the status pin of the LED driver is at a high level, indicating that the LED driver normally works, and ending the backlight test; if the status pin of the LED driver is at low level, it indicates that the LED driver is working abnormally, and the microprocessor 152 reads and stores the status information of the LED driver whose status pin is at low level. For example, the microprocessor 152 performs fixed-point detection on the LED driver with abnormal operation, reads the operating state of each channel of the LED driver with abnormal operation, determines whether the abnormal LED driver has problems such as open circuit, short circuit, and over-temperature, and stores the obtained error information in the flash memory inside the ARM processor.

To sum up, the utility model provides a testing arrangement and liquid crystal display device are shaded, testing arrangement is shaded includes microprocessor and a plurality of LED driver. The LED drivers are connected with the microprocessor to receive the backlight driving signals provided by the microprocessor and control the backlight brightness of the backlight partitions according to the backlight driving signals. The backlight testing device further comprises at least one first serial port expansion chip, each first serial port expansion chip comprises a first interface and a plurality of second interfaces, the first interfaces are electrically connected with the microprocessor, each second interface is electrically connected with a status pin of the corresponding LED driver, and the first serial port expansion chips are used for providing status information of each LED driver for the microprocessor. In the utility model, the electrical connection between the microprocessor and the plurality of LED drivers is realized through the first serial port extension chip, the resources of the I/O port of the microprocessor are greatly saved on the basis of not changing the original circuit structure, and the test cost is favorably reduced; meanwhile, the subsequent backlight power consumption, brightness and other functions can be tested more conveniently, and the testing efficiency is improved.

In a preferred embodiment, the backlight testing device further comprises a dial switch, and the tester adjusts the backlight current value through the dial switch during the backlight test. The current value can be visually displayed through the dial switch, so that a display screen for displaying the current backlight current is saved, the test cost is further saved, and the test efficiency is improved.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

In accordance with the embodiments of the present invention as set forth above, these embodiments are not exhaustive and do not limit the invention to the precise embodiments described. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and its various embodiments with various modifications as are suited to the particular use contemplated.

Claims (10)

1. A backlight testing apparatus, comprising: a microprocessor for providing a backlight driving signal; characterized in that, the backlight testing device further comprises:

a plurality of LED drivers connected with the microprocessor and receiving the backlight driving signal, controlling backlight brightness of a plurality of backlight partitions according to the backlight driving signal,

and each first serial port expansion chip comprises a first interface and a plurality of second interfaces, the first interface is electrically connected with the microprocessor, each second interface is electrically connected with a corresponding status pin of the LED driver, the first serial port expansion chip provides status information of each LED driver to the microprocessor, and the microprocessor judges the level state of the status pin of the LED driver according to the status information after receiving the status information.

2. The backlight testing device of claim 1, further comprising:

a dial switch; and

and the dial switch is electrically connected with the microprocessor through the second serial port expansion chip.

3. The backlight testing device of claim 1, further comprising a signal processor electrically connected to the microprocessor,

the signal processor receives an input image signal, analyzes the input image signal on the basis of the plurality of backlight partitions, and provides the dimming value of each backlight partition to the microprocessor, and the microprocessor obtains the backlight driving signal according to the dimming value.

4. The backlight testing device of claim 1, further comprising a power consumption detection unit connected between the microprocessor and the plurality of LED drivers for providing power consumption information of the plurality of LED drivers to the microprocessor.

5. The backlight test device of claim 3, wherein the microprocessor further comprises a third interface, the third interface being electrically connected to the signal processor, the microprocessor providing initialization data to the signal processor via the third interface.

6. The backlight test device of claim 4, wherein the microprocessor further comprises a memory for storing the state information and power consumption information.

7. The backlight testing device of claim 4, wherein the microprocessor further comprises a fourth interface, the fourth interface is connected with an upper computer, and the upper computer is used for displaying the state information and the power consumption information of the LED driver and debugging the microprocessor through the fourth interface.

8. The backlight test device of claim 3, wherein the signal processor is a timing controller.

9. The backlight test device of claim 1, wherein the microprocessor is an ARM processor.

10. A display comprising the backlight testing apparatus of any one of claims 1 to 9.

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