CN114220398A - Backlight control method and display device - Google Patents
Backlight control method and display device Download PDFInfo
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
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- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
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- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
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Abstract
The invention discloses a backlight control method and display equipment.A MCU generates a first vertical synchronizing signal with the same frequency as the backlight vertical synchronizing signal when receiving the backlight vertical synchronizing signal sent by an SOC, performs digit conversion on the backlight brightness data sent by the SOC to obtain the backlight brightness data with digits suitable for a backlight driving chip, and finally sends the first vertical synchronizing signal and the converted backlight brightness data to the backlight driving chip so that the backlight driving chip outputs the backlight driving signal to an LED lamp bar for backlight synchronous adjustment based on the first vertical synchronizing signal and the converted backlight brightness data. The MCU can automatically generate a first vertical synchronization signal along with the backlight vertical synchronization signal of the SOC, so that backlight brightness data frame loss and frame crossing are avoided, backlight synchronization adjustment can be effectively carried out, and the LD effect of the display device is improved.
Description
Technical Field
The present invention relates to the field of display technologies, and in particular, to a backlight control method and a display device.
Background
In recent years, regional light control televisions are developed rapidly, a display picture is partitioned, and a regional light control technology is adopted, so that a backlight partition can be closed locally, the contrast of screen brightness is more prominent, and the display effect is better.
In an existing television regional Light control system, a television main board obtains backlight brightness data according to an image signal, and sends the backlight brightness data to an MCU of an LD (local dimming) Driver board, and the backlight brightness data is processed by the MCU and sent to an LED (Light Emitting Diode) Driver IC for controlling an LED lamp to Light up. When the television mainboard SOC (system on a Chip) outputs backlight brightness data, a VSYNC vertical synchronization (vertical synchronization) signal is output at the same time, the SOC backlight vertical synchronization signal is changed, and according to the change of the image signal frequency, if the vertical synchronization signal frequency adopted when the MCU (Micro Controller Unit) sends the backlight brightness data to the LED Driver IC is fixed, frame loss and frame crossing of the backlight brightness data will be caused, so that the backlight brightness data is disordered, and the television has no LD effect. The SOC is directly connected with the LED Driver IC without the MCU, and cannot be used in the condition of a multi-partition LD television because the SOC cannot support the huge data volume of the multi-partition and the follow-up updating and maintenance are difficult.
Disclosure of Invention
The invention aims to provide a backlight control method and display equipment, which can avoid frame loss and frame crossing of backlight brightness data, effectively carry out backlight synchronous regulation and improve the LD (laser diode) effect of the display equipment.
In order to solve the technical problem, the invention provides a backlight control method, which is used for regional light control equipment, wherein the regional light control equipment comprises an SOC, a power supply, an MCU, a backlight driving chip and an LED lamp bar, and the method comprises the following steps:
the SOC acquires a backlight vertical synchronization signal in the image signal according to the acquired image signal;
the SOC analyzes the image signal, calculates backlight brightness data and sends the backlight brightness data and the backlight vertical synchronization signal to the MCU;
the MCU receives the backlight vertical synchronization signal sent by the SOC through a designated first GPIO, and generates a first vertical synchronization signal when receiving the backlight vertical synchronization signal sent by the SOC, wherein the frequency of the first vertical synchronization signal is the same as that of the backlight vertical synchronization signal;
the MCU performs digit conversion on the backlight brightness data sent by the SOC to obtain the backlight brightness data with digits suitable for the backlight driving chip;
the MCU sends the first vertical synchronizing signal and the converted backlight brightness data to the backlight driving chips, and the number of the backlight driving chips is one or more;
and the backlight driving chip outputs a backlight driving signal to control the LED lamp strip to carry out backlight adjustment based on the first vertical synchronous signal and the converted backlight brightness data.
Preferably, when the MCU receives the backlight vertical synchronization signal sent by the SOC by designating the first GPIO, if the MCU cannot receive the backlight vertical synchronization signal sent by the SOC during operation, the MCU determines that the signal fails, and sends a second vertical synchronization signal with a fixed frequency to the backlight driver chip, where the frequency of the second vertical synchronization signal is a preset value or a frequency value before the signal fails.
Preferably, when the MCU receives the backlight vertical synchronization signal sent by the SOC, the method further includes:
the MCU calculates the frequency of the backlight vertical synchronizing signal obtained from the SOC as a first frequency and stores the first frequency, and the first frequency and the backlight vertical synchronizing signal change synchronously;
the MCU generates an HSYNC signal according to the first frequency, and the HSYNC signal changes along with the first frequency;
and the MCU sends the HSYNC signal, the first vertical synchronizing signal and the backlight brightness data to the backlight driving chip simultaneously.
Preferably, the first and second liquid crystal materials are,
the frequency of the HSYNC signal is positively correlated with the first frequency;
when the backlight driving signal is a PWM signal, the following relationship is provided:
f(HSYNC)=f1×(PWM_PER+1)×(PWM_FRQ+1)
wherein f (HSYNC) represents a frequency of an HSYNC signal, f1 represents a first frequency, PWM _ PER is a clock number in a period of the PWM signal, and PWM _ FRQ is a frequency multiplication coefficient of the PWM signal;
and the backlight driving chip outputs a corresponding PWM waveform to control the brightness of the LED lamp strip according to the received HSYNC signal.
Preferably, the sending, by the MCU, the first vertical synchronization signal and the converted backlight luminance data to the backlight driver chip includes:
the MCU sends the first vertical synchronizing signal and the converted backlight brightness data through one-way or multi-way SPI communication;
the LED lamp strip is characterized in that the MCU is communicated with any SPI, the number of connected backlight driving chips is 10, the MCU divides the backlight brightness data into a plurality of partitions, and any backlight driving chip receives the backlight brightness data of one partition to control the LED lamp strip to carry out backlight adjustment.
Preferably, the generating a first vertical synchronization signal when receiving the backlight vertical synchronization signal sent by the SOC, the first vertical synchronization signal having a frequency identical to a frequency of the backlight vertical synchronization signal includes:
when a change edge of the backlight vertical synchronization signal sent by the SOC is captured, generating a change edge of the first vertical synchronization signal which is the same as the change edge of the backlight vertical synchronization signal, wherein the change edge is a rising edge or a falling edge;
generating the level of the first vertical synchronization signal identical to the level of the backlight vertical synchronization signal when capturing the level of the backlight vertical synchronization signal transmitted by the SOC, the level being a high level or a low level.
In order to solve the above technical problem, the present invention further provides a display device, where the display device employs a regional light control device, and the regional light control device employs the above backlight control method.
Preferably, the backlight driving chip used by the area light control device is IW 7027.
The invention discloses a backlight control method and display equipment.A MCU generates a first vertical synchronizing signal with the same frequency as the backlight vertical synchronizing signal when receiving the backlight vertical synchronizing signal sent by an SOC, performs digit conversion on the backlight brightness data sent by the SOC to obtain the backlight brightness data with digits suitable for a backlight driving chip, and finally sends the first vertical synchronizing signal and the converted backlight brightness data to the backlight driving chip so that the backlight driving chip outputs the backlight driving signal to an LED lamp bar for backlight synchronous adjustment based on the first vertical synchronizing signal and the converted backlight brightness data. Therefore, by adopting the mode, the MCU can automatically generate the first vertical synchronizing signal along with the backlight vertical synchronizing signal of the SOC, so that the frequency of the first vertical synchronizing signal is consistent with that of the backlight vertical synchronizing signal, the backlight brightness data frame loss and frame crossing are avoided, the backlight synchronous adjustment can be effectively carried out, and the LD effect of the display device is improved.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed in the prior art and the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
Fig. 1 is a schematic flow chart of a backlight control method according to the present invention;
FIG. 2 is a schematic diagram illustrating a backlight control method according to the present invention;
FIG. 3 is a schematic diagram illustrating the effect of a fixed-frequency vertical synchronization signal transmitted by a MCU according to the prior art;
FIG. 4 is a schematic diagram illustrating the effect of MCU sending following SOC vertical synchronization signal according to the present invention;
FIG. 5 is a schematic diagram of an area backlight device used in the display device of the present invention.
Detailed Description
The core of the invention is to provide a backlight control method and a display device, which avoid frame loss and frame crossing of backlight brightness data, effectively perform backlight synchronous adjustment and improve the LD effect of the display device.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The first embodiment is as follows:
referring to the drawings, fig. 1 is a schematic flow chart of a backlight control method provided in the present application, and fig. 2 is a schematic principle diagram of the backlight control method provided in the present application.
The invention provides a backlight control method, which is used for regional light control equipment, wherein the regional light control equipment comprises an SOC1, a power supply 5, an MCU2, a backlight driving chip 3 and an LED light bar 4, and the method comprises the following steps:
s11: the SOC1 acquires a backlight vertical synchronization signal in the image signal according to the acquired image signal;
s12: the SOC1 analyzes the image signal, calculates backlight luminance data, and transmits the backlight luminance data and the backlight vertical synchronization signal to the MCU 2;
s13: the MCU2 receives the backlight vertical synchronization signal transmitted by the SOC1 by designating a first GPIO, and generates a first vertical synchronization signal having the same frequency as the backlight vertical synchronization signal when receiving the backlight vertical synchronization signal transmitted by the SOC 1;
s14: the MCU2 converts the digit of the received backlight brightness data sent by the SOC1 to obtain the backlight brightness data with the digit suitable for the backlight driving chip 3;
s15: the MCU2 sends the first vertical synchronizing signal and the converted backlight brightness data to the backlight driving chips 3, and the number of the backlight driving chips 3 is one or more;
s16: the backlight driving chip 3 outputs a backlight driving signal to control the LED light bar 4 to perform backlight adjustment based on the first vertical synchronization signal and the converted backlight luminance data.
Referring to fig. 3, fig. 3 is a schematic diagram illustrating an effect of a MCU transmitting a vertical synchronization signal with a fixed frequency according to the prior art.
In the LD technique, considering that the frequency of the backlight vertical synchronization signal received by the MCU2 from the SOC1 varies according to the frequency of the image signal, the frequency of the backlight vertical synchronization signal needs to be consistent with the frequency of the image signal, but when the vertical synchronization signal transmitted by the MCU2 to the backlight driving chip 3 is a fixed frequency, there may be problems of frame loss and frame crossing of backlight luminance data, making the backlight luminance data confused and the display device without LD effect.
In order to solve the above technical problem, in the present application, the SOC1 obtains the backlight vertical synchronization signal in the image signal according to the acquired image signal, analyzes the image signal, calculates backlight luminance data, and sends the backlight luminance data and the backlight vertical synchronization signal to the MCU 2; the MCU2 can automatically follow the backlight vertical synchronization signal of the SOC1, generate a first vertical synchronization signal when receiving the backlight vertical synchronization signal transmitted by the SOC1 by designating a first GPIO (General-Purpose Input/Output Ports) such that the frequency of the first vertical synchronization signal is the same as the frequency of the backlight vertical synchronization signal. Meanwhile, considering that the bit number of the backlight luminance data sent to the backlight driving chip 3 needs to be adapted to the backlight driving chip 3, in the present application, when receiving the backlight luminance data sent by the SOC1, the MCU2 performs bit number conversion on the backlight luminance data sent by the SOC1 to obtain the backlight luminance data whose bit number is adapted to the backlight driving chip 3. When the backlight driving signal is a PWM (Pulse width modulation) signal, considering that the first vertical synchronization signal is used for adjusting backlight synchronization, which is a reference of backlight synchronization adjustment, the backlight luminance data has a mapping relationship with a duty ratio of the PWM signal, and the backlight driving signal adjusts the backlight luminance through the duty ratio, in this application, the MCU2 sends the first vertical synchronization signal and the converted backlight luminance data to the backlight driving chip 3, and the number of the backlight driving chips 3 is one or more, so that the backlight driving chip 3 outputs the backlight driving signal to the LED light bar 4 for backlight synchronization adjustment based on the first vertical synchronization signal and the converted backlight luminance data.
Referring to fig. 4, fig. 4 is a schematic diagram illustrating an effect of the MCU transmitting the following SOC vertical synchronization signal according to the present invention.
Therefore, by adopting the mode, the MCU2 can generate the first vertical synchronizing signal with the frequency consistent with that of the backlight vertical synchronizing signal along with the backlight vertical synchronizing signal of the SOC1, the problems of frame loss and frame crossing of backlight brightness data in the transmission process are solved, and the stability of a local dimming system of a display device is improved.
For example, when the frequency of the backlight vertical synchronization signal transmitted by the SOC1 is received as 60HZ, the first vertical synchronization signal of 60HZ having the same frequency as the backlight vertical synchronization signal is generated. Meanwhile, the backlight brightness data with 8 bits sent by the SOC1 can be converted into backlight brightness data with 12 bits and suitable for the backlight driving chip 3. And sends the first vertical synchronization signal of 60HZ and the converted backlight luminance data of 12 bits to the backlight driving chip 3, so that the backlight driving chip 3 outputs the backlight driving signal to the LED light bar 4 for backlight synchronization adjustment based on the first vertical synchronization signal and the converted backlight luminance data.
In addition, the SOC1 may be disposed on the LD driving board, and the backlight brightness data is calculated by a local dimming algorithm according to the collected image signal, which is not limited herein.
The backlight driving signal may be, but is not limited to, a pulse width modulation PWM signal, and a duty ratio of the PWM signal has a mapping relation with the backlight luminance data, where the larger the backlight luminance data is, the larger the duty ratio is, the smaller the backlight luminance data is, and the smaller the duty ratio is. For example, the luminance data range is 0-255, the duty ratio is maximum if the luminance data is 255, and the duty ratio is minimum if the data of one partition is 0.
The SOC1 and the MCU2 and the MCU2 and the backlight driver chip 3 may communicate with each other through SPI (Serial Peripheral Interface), but may also communicate with each other in other manners.
The power supply 5 may be, but is not limited to, a DC-DC (Direct current-Direct current) power supply for supplying power to the MCU2, the SOC1, and the backlight driving chip 3.
In summary, the backlight control method of the present application realizes that the first vertical synchronization signal is generated automatically following the backlight vertical synchronization signal of the SOC1, so that the frequency of the first vertical synchronization signal is consistent with the frequency of the backlight vertical synchronization signal, thereby avoiding frame loss and frame crossing of backlight luminance data, effectively performing backlight synchronization adjustment, and improving the LD effect of the display device.
Example two:
on the basis of the above embodiment, a preferred embodiment is provided, when the MCU2 specifies the first GPIO to receive the backlight vertical synchronization signal sent by the SOC1, if the MCU2 cannot receive the backlight vertical synchronization signal sent by the SOC1 during operation, the MCU2 determines that there is a signal failure and sends a second vertical synchronization signal with a fixed frequency to the backlight driver chip 3, where the frequency of the second vertical synchronization signal is a preset value or a frequency value before the signal failure.
Considering that SOC1 cannot timely send a backlight vertical synchronization signal to MCU2 before initialization is completed or when communication interference or communication line failure occurs, in the present embodiment, when the MCU2 receives the backlight vertical synchronization signal transmitted from the SOC1 by designating the first GPIO, if the MCU2 cannot receive the backlight vertical synchronization signal transmitted by the SOC1 during operation, the MCU2 determines that the signal is faulty, and generates a second vertical synchronization signal of a fixed frequency, which is a preset value or a frequency value before a signal failure, so that the backlight driving chip 3 can output the backlight driving signal to the LED light bar 4 for backlight synchronization adjustment based on the second vertical synchronization signal with fixed frequency and the converted backlight luminance data, thereby avoiding frame loss and frame crossing of the backlight luminance data and improving the LD effect of the display device. For example, the frequency of the second vertical synchronization signal may be 50HZ or 60 HZ.
As a preferred embodiment, when receiving the backlight vertical synchronization signal sent by the SOC1, the MCU2 further includes:
the MCU2 calculates its frequency from the backlight vertical synchronization signal obtained from the SOC1, as a first frequency that varies in synchronization with the backlight vertical synchronization signal, and stores it;
the MCU2 generates an HSYNC signal according to the first frequency, wherein the HSYNC signal changes along with the first frequency;
the MCU2 sends the HSYNC signal, the first vertical sync signal, and the backlight luminance data to the backlight driver chip 3 simultaneously.
Considering that if the frequency of the HSYNC signal generated by the MCU2 is fixed, it may cause the backlight driving signal output by the backlight driving chip 3 when receiving the HSYNC signal to be mismatched with the LED light bar 4, which may cause backlight flicker, in this embodiment, when the MCU2 receives the backlight vertical synchronization signal transmitted by the SOC1, the MCU2 calculates the frequency of the backlight vertical synchronization signal obtained from the SOC1, stores the frequency as a first frequency, the first frequency changes in synchronization with the backlight vertical synchronization signal, then generates the HSYNC signal according to the first frequency, the HSYNC signal changes along with the first frequency, and then the MCU2 transmits the HSYNC signal and the first vertical synchronization signal, and the backlight luminance data to the backlight driving chip 3 simultaneously. Therefore, the HSYNC signal generated by the MCU2 automatically changes with the change of the backlight vertical synchronization signal sent by the SOC1, so that the backlight driving chip 3 outputs the backlight driving signal of the appropriate LED light bar 4 based on the HSYNC signal, and the problem of backlight flicker caused by the backlight driving chip 3 driven by the HSYNC signal with fixed frequency when the image signal scenes with different frequencies are switched is solved, thereby smoothing the transition of backlight change and improving the experience of the user.
As a preferred embodiment, the frequency of the HSYNC signal is positively correlated with the first frequency;
when the backlight driving signal is a PWM signal, the following relationship is provided:
f(HSYNC)=f1×(PWM_PER+1)×(PWM_FRQ+1)
wherein f (HSYNC) represents the frequency of the HSYNC signal, f1 represents the first frequency, PWM _ PER is the clock number in the period of the PWM signal, and PWM _ FRQ is the frequency multiplication coefficient of the PWM signal;
the backlight driving chip 3 outputs a corresponding PWM waveform to control the brightness of the LED light bar 4 according to the received HSYNC signal.
In order to determine the positive correlation between the frequency of the HSYNC signal and the first frequency when the backlight driving signal is the PWM signal, in this embodiment, the positive correlation between the frequency of the HSYNC signal and the first frequency may be determined by a first frequency generation relational expression and the frequency of the HSYNC signal, and the HSYNC signal may be generated according to f (HSYNC) 1 × (PWM _ PER +1) × (PWM _ FRQ +1), where f (HSYNC) represents the frequency of the HSYNC signal, f1 represents the first frequency, PWM _ PER represents the number of clocks in the period of the PWM signal, and PWM _ FRQ represents a frequency multiplication coefficient of the PWM signal, and the generated backlight driving chip 3 drives the LED light bar 4 to output the PWM signal in a proper manner by sufficiently considering the first frequency, the number of clocks in the period of the PWM signal, and PWM _ FRQ of the frequency multiplication coefficient of the PWM signal, so that a phenomenon of flickering of the backlight does not occur, the backlight change transition is smooth, and the experience of a user is improved.
For example, when the first frequency is 50HZ, the frequency of the HSYNC signal generated according to the first frequency and the frequency generation relation of the HSYNC signal is 2MHZ, and the backlight driving chip 3 outputs a PWM signal with a frequency of 500HZ to the LED light bar 4; when the first frequency is 60HZ, the frequency of the HSYNC signal generated according to the first frequency and the frequency generation relation of the HSYNC signal is 2.4MHZ, and the backlight driving chip 3 outputs a PWM signal with a frequency of 600HZ to the LED light bar 4. Therefore, the frequency of the HSYNC signal can automatically adapt to the first frequency, so that the backlight driving chip 3 is driven to output a synchronous PWM signal, and the backlight flicker phenomenon does not exist.
In addition, the frequency of the PWM signal is a product of the first frequency and PWM _ FRQ of a frequency multiplication coefficient of the PWM signal, and the application is not particularly limited herein. For example, the PWM _ FRQ is 5, the first frequency is 60HZ, and then the frequency of the PWM signal output by the backlight driving chip 3 is 300 HZ.
As a preferred embodiment, the MCU2 sends the first vertical synchronization signal and the converted backlight luminance data to the backlight driver chip 3, and includes:
the MCU2 sends a first vertical synchronizing signal and the converted backlight brightness data through one-way or multi-way SPI communication;
any SPI communication of MCU2, the quantity of the drive chip 3 that is shaded of connecting is 10, and MCU2 divide into a plurality of subregion with the luminance data of being shaded, and any drive chip 3 that is shaded receives the luminance data of being shaded of a subregion, and control LED lamp strip 4 is shaded and is adjusted.
Considering the local dimming of the multi-partition LD television, in this embodiment, the MCU2 may send the first vertical synchronization signal and the converted backlight luminance data through one or more SPI communications, any one of the SPI communications of the MCU2 is used, the number of the connected backlight driving chips 3 is 10, the MCU2 divides the backlight luminance data into a plurality of partitions, any one of the backlight driving chips 3 receives the backlight luminance data of one partition, and controls the LED light bar 4 to perform backlight adjustment, thereby realizing the processing of the huge data volume of the multi-partition LD television and reducing the difficulty of subsequent update and maintenance.
Example three:
as a preferred embodiment, generating a first vertical synchronization signal when receiving a backlight vertical synchronization signal sent by the SOC1, where the frequency of the first vertical synchronization signal is the same as the frequency of the backlight vertical synchronization signal includes:
generating a change edge of a first vertical synchronization signal which is the same as the change edge of the backlight vertical synchronization signal when the change edge of the backlight vertical synchronization signal sent by the SOC1 is captured, wherein the change edge is a rising edge or a falling edge;
when capturing the level of the backlight vertical synchronization signal transmitted by the SOC1, the level of the first vertical synchronization signal is generated to be the same as the level of the backlight vertical synchronization signal, and the level is a high level or a low level.
In the present embodiment, the MCU2 receives the backlight vertical synchronization signal transmitted by the SOC1, and specifically, captures the variation edge and level of the backlight vertical synchronization signal, and when the variation edge of the backlight vertical synchronization signal transmitted by the SOC1 is captured, generates the variation edge of the first vertical synchronization signal that is the same as the variation edge of the backlight vertical synchronization signal; when the level of the backlight vertical synchronizing signal sent by the SOC1 is captured, the level of the first vertical synchronizing signal which is the same as the level of the backlight vertical synchronizing signal is generated, the backlight vertical synchronizing signal of the SOC1 is followed and the first vertical synchronizing signal with the same frequency is generated, the problems of frame loss and frame crossing of backlight brightness data in the transmission process are solved, and the stability of a regional dimming system of a display device is improved.
For example, when the rising edge of the backlight vertical synchronization signal sent by SOC1 is captured, the first vertical synchronization signal of the same frequency as the high level is generated, and when the backlight vertical synchronization signal sent by SOC1 is captured as the high level, the first vertical synchronization signal of the same frequency as the high level is generated, the synchronization between the backlight vertical synchronization signal and the first vertical synchronization signal can be ensured by the above method, so that the frequency of the generated first vertical synchronization signal and the frequency of the backlight vertical synchronization signal can be kept consistent, and therefore, the phenomena of frame loss and frame crossing of backlight brightness data can not occur, and the image quality of the display device is greatly improved.
In addition, the MCU2 may designate the backlight vertical synchronization signal transmitted by the SOC1 received by the first GPIO transmission and designate the first vertical synchronization signal generated by the second GPIO transmission to the backlight driving chip 3, which is not limited herein.
Referring to fig. 5, fig. 5 is a schematic structural diagram of an area backlight device used in a display device of the present invention.
The invention also provides a display device, wherein the display device adopts the regional light control device, and the regional light control device implements the backlight control method.
For the introduction of the display device provided by the present invention, please refer to the above method embodiments, which are not repeated herein.
Preferably, the backlight driving chip used by the area light control device is IW 7027.
It is to be noted that, in the present specification, relational terms such as first and second, and the like are 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.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (8)
1. A backlight control method is used for regional light control equipment, wherein the regional light control equipment comprises an SOC, a power supply, an MCU, a backlight driving chip and an LED lamp bar, and is characterized by comprising the following steps:
the SOC acquires a backlight vertical synchronization signal in the image signal according to the acquired image signal;
the SOC analyzes the image signal, calculates backlight brightness data and sends the backlight brightness data and the backlight vertical synchronization signal to the MCU;
the MCU receives the backlight vertical synchronization signal sent by the SOC through a designated first GPIO, and generates a first vertical synchronization signal when receiving the backlight vertical synchronization signal sent by the SOC, wherein the frequency of the first vertical synchronization signal is the same as that of the backlight vertical synchronization signal;
the MCU performs digit conversion on the backlight brightness data sent by the SOC to obtain the backlight brightness data with digits suitable for the backlight driving chip;
the MCU sends the first vertical synchronizing signal and the converted backlight brightness data to the backlight driving chips, and the number of the backlight driving chips is one or more;
and the backlight driving chip outputs a backlight driving signal to control the LED lamp strip to carry out backlight adjustment based on the first vertical synchronous signal and the converted backlight brightness data.
2. The backlight control method of claim 1, wherein when the MCU receives the backlight vertical synchronization signal sent by the SOC through the designated first GPIO, if the MCU cannot receive the backlight vertical synchronization signal sent by the SOC during operation, the MCU determines that there is a signal failure and sends a second vertical synchronization signal with a fixed frequency to the backlight driver chip, where the frequency of the second vertical synchronization signal is a preset value or a frequency value before the signal failure.
3. The backlight control method of claim 1, wherein when the MCU receives the backlight vertical synchronization signal sent by the SOC, the method further comprises:
the MCU calculates the frequency of the backlight vertical synchronizing signal obtained from the SOC as a first frequency and stores the first frequency, and the first frequency and the backlight vertical synchronizing signal change synchronously;
the MCU generates an HSYNC signal according to the first frequency, and the HSYNC signal changes along with the first frequency;
and the MCU sends the HSYNC signal, the first vertical synchronizing signal and the backlight brightness data to the backlight driving chip simultaneously.
4. A backlight control method as claimed in claim 3,
the frequency of the HSYNC signal is positively correlated with the first frequency;
when the backlight driving signal is a PWM signal, the following relationship is provided:
f(HSYNC)=f1×(PWM_PER+1)×(PWM_FRQ+1)
wherein f (HSYNC) represents a frequency of an HSYNC signal, f1 represents a first frequency, PWM _ PER is a clock number in a period of the PWM signal, and PWM _ FRQ is a frequency multiplication coefficient of the PWM signal;
and the backlight driving chip outputs a corresponding PWM waveform to control the brightness of the LED lamp strip according to the received HSYNC signal.
5. The backlight control method of claim 1, wherein the MCU sends the first vertical synchronization signal and the converted backlight luminance data to the backlight driver chip, comprising:
the MCU sends the first vertical synchronizing signal and the converted backlight brightness data through one-way or multi-way SPI communication;
the LED lamp strip is characterized in that the MCU is communicated with any SPI, the number of connected backlight driving chips is 10, the MCU divides the backlight brightness data into a plurality of partitions, and any backlight driving chip receives the backlight brightness data of one partition to control the LED lamp strip to carry out backlight adjustment.
6. A backlight control method as claimed in any one of claims 1 to 5,
generating a first vertical synchronization signal when receiving the backlight vertical synchronization signal sent by the SOC, wherein a frequency of the first vertical synchronization signal is the same as a frequency of the backlight vertical synchronization signal, and the method comprises the following steps:
when a change edge of the backlight vertical synchronization signal sent by the SOC is captured, generating a change edge of the first vertical synchronization signal which is the same as the change edge of the backlight vertical synchronization signal, wherein the change edge is a rising edge or a falling edge;
generating the level of the first vertical synchronization signal identical to the level of the backlight vertical synchronization signal when capturing the level of the backlight vertical synchronization signal transmitted by the SOC, the level being a high level or a low level.
7. A display device, characterized in that the display device employs an area light control device, and the area light control device employs a backlight control method as claimed in any one of claims 1 to 6.
8. The display device according to claim 7, wherein the backlight driving chip model used by the area light control device is IW 7027.
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Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20030178951A1 (en) * | 2002-03-20 | 2003-09-25 | Park Jung Kook | Low noise backlight system for use in display device and method for driving the same |
CN101763781A (en) * | 2008-12-24 | 2010-06-30 | 三星电子株式会社 | Display apparatus and control method thereof |
CN104332140A (en) * | 2014-10-28 | 2015-02-04 | 深圳创维-Rgb电子有限公司 | Backlight driving system for regional dimming and regional dimming method |
CN105976770A (en) * | 2016-07-21 | 2016-09-28 | 深圳创维-Rgb电子有限公司 | Method for controlling dimming signal and device and system thereof |
CN106097983A (en) * | 2016-07-27 | 2016-11-09 | 青岛海信电器股份有限公司 | Method for controlling backlight thereof, device and liquid crystal indicator in liquid crystal indicator |
CN106652919A (en) * | 2016-09-09 | 2017-05-10 | 青岛海信电器股份有限公司 | Image display method and display apparatus |
CN107195275A (en) * | 2017-07-27 | 2017-09-22 | 青岛海信电器股份有限公司 | A kind of multi partition dynamic backlight driving method and TV |
CN111010519A (en) * | 2019-12-23 | 2020-04-14 | 深圳创维-Rgb电子有限公司 | Control method of display device, television and storage medium |
CN212694810U (en) * | 2020-07-31 | 2021-03-12 | 深圳市康冠科技股份有限公司 | High-partition regional light control television |
-
2021
- 2021-12-20 CN CN202111565537.9A patent/CN114220398A/en active Pending
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20030178951A1 (en) * | 2002-03-20 | 2003-09-25 | Park Jung Kook | Low noise backlight system for use in display device and method for driving the same |
CN101763781A (en) * | 2008-12-24 | 2010-06-30 | 三星电子株式会社 | Display apparatus and control method thereof |
CN104332140A (en) * | 2014-10-28 | 2015-02-04 | 深圳创维-Rgb电子有限公司 | Backlight driving system for regional dimming and regional dimming method |
CN105976770A (en) * | 2016-07-21 | 2016-09-28 | 深圳创维-Rgb电子有限公司 | Method for controlling dimming signal and device and system thereof |
CN106097983A (en) * | 2016-07-27 | 2016-11-09 | 青岛海信电器股份有限公司 | Method for controlling backlight thereof, device and liquid crystal indicator in liquid crystal indicator |
CN106652919A (en) * | 2016-09-09 | 2017-05-10 | 青岛海信电器股份有限公司 | Image display method and display apparatus |
CN107195275A (en) * | 2017-07-27 | 2017-09-22 | 青岛海信电器股份有限公司 | A kind of multi partition dynamic backlight driving method and TV |
CN111010519A (en) * | 2019-12-23 | 2020-04-14 | 深圳创维-Rgb电子有限公司 | Control method of display device, television and storage medium |
CN212694810U (en) * | 2020-07-31 | 2021-03-12 | 深圳市康冠科技股份有限公司 | High-partition regional light control television |
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