CN117789656A

CN117789656A - Driving method, display driving chip, display module, processor and display

Info

Publication number: CN117789656A
Application number: CN202211154161.7A
Authority: CN
Inventors: 吕容恺; 李元; 申孟虎
Original assignee: Huawei Device Co Ltd
Current assignee: Huawei Device Co Ltd
Priority date: 2022-09-21
Filing date: 2022-09-21
Publication date: 2024-03-29

Abstract

The application provides a driving method which is applied to a self-luminous display, wherein the self-luminous display comprises a pixel driving circuit, the pixel driving circuit is used for driving each sub-pixel in the self-luminous display to display images, and the pixel driving circuit comprises a driving transistor, and the driving transistor is provided with a source electrode and a drain electrode; the display driving method includes: acquiring the image content currently displayed by the self-luminous display, wherein the image content comprises the image brightness currently displayed by the self-luminous display and the load current required by displaying the image; regulating the voltage difference V between the source and drain of the driving transistor according to the image brightness and the load current _ds To keep the drive transistor operating in the saturation region. The application also provides a display driving chip, a display module, an application processor and a self-luminous display.

Description

Driving method, display driving chip, display module, processor and display

Technical Field

The present disclosure relates to the field of image display technologies, and more particularly, to a driving method, a display driving chip applying the driving method, a display module including the display driving chip, an application processor applying the driving method, and a self-luminous display including the display module or the processor.

Background

A self-luminous display (e.g., an OLED display) includes a display driving chip including driving transistors for driving respective sub-pixels in the self-luminous display to emit image light.

Currently, the display brightness of self-luminous displays is increasingly demanded. To achieve higher display brightness, it is often necessary to reduce the voltage across the self-luminous display between the operating voltage ELVDD and the common voltage ELVSS. After the voltage across ELVDD and ELVSS decreases, the driving transistor no longer operates in the saturation region, resulting in uneven display and color cast of the self-luminous display. In order to ensure that the driving transistor operates in a saturation region to improve the non-uniformity (the non-uniformity of the light-emitting brightness of the light-emitting element in each sub-pixel, and the non-uniformity of the color, brightness and darkness of the whole pixel or the whole picture) and the color cast problem, it is commonly used to reduce ELVSS. However, after ELVSS is reduced, under the black screen of the self-luminous display, the voltage across ELVDD and ELVSS increases, resulting in a large increase in bright spots under the black screen, and a large increase in yield.

In some technical schemes, the value of ELVSS is adjusted during the operation of the self-luminous display, so as to improve the technical problem of pixel bright spots on the basis of ensuring the display brightness. However, the manner of adjusting the ELVSS value in this technical solution is still difficult to meet the requirements, and the self-luminous display still has a bright spot risk.

Disclosure of Invention

A first aspect of the present invention provides a driving method applied to a self-light emitting display, the self-light emitting display including a pixel driving circuit for driving each sub-pixel in the self-light emitting display to display an image, the pixel driving circuit including a driving transistor having a source and a drain; the display driving method includes: acquiring image content currently displayed by the self-luminous display, wherein the image content comprises the image content currently displayed by the self-luminous displayImage brightness and load current required to display an image; regulating the voltage difference V between the source and drain of the driving transistor according to the image brightness and the load current _ds To keep the drive transistor operating in the saturation region.

The self-luminous display comprises a pixel driving circuit, wherein the pixel driving circuit comprises a driving transistor, and the driving transistor is used for driving the luminous elements in all sub-pixels in the self-luminous display to emit light. The driving transistor has a source and a drain, and a voltage difference between the source and the drain is denoted as V _ds The current is denoted as I _ds . According to the operation characteristics of the driving transistor, when the driving transistor operates in the saturation region, the voltage difference V _ds The rise does not cause current I _ds Is a variation of (c). However, in order to meet the high brightness requirement of the self-luminous display, the voltage difference V needs to be increased _ds . With voltage difference V _ds The drive transistor will no longer operate in the saturation region, voltage difference V _ds An elevation will result in I _ds Enlargement, I _ds When the display is enlarged, bright spots are likely to appear when a dark picture is displayed on the self-luminous display. The driving method can adjust the voltage difference V in real time according to the image content displayed by the self-luminous display _ds Avoiding voltage difference V _ds Rise too high to make the driving transistor always operate in the saturation region, so that when the voltage difference V _ds The rise does not cause current I _ds The rise can avoid bright spots under low-brightness pictures, and simultaneously, the high-brightness display requirement of the self-luminous display is ensured. The image content is mainly represented by both the image brightness and the load current required to display the image. In some embodiments, the image content is determined by acquiring the image brightness and the load current to determine the voltage difference V _ds Adjusted to a value corresponding to a particular image brightness and load current.

In some embodiments, the source of the driving transistor inputs the power voltage of the self-luminous display, and the drain inputs the reference voltage of the self-luminous display; the voltage difference V between the source and the drain of the driving transistor is regulated _ds Comprising: regulating stationThe value of the supply voltage and/or the reference voltage, thereby adjusting the voltage difference V between the source and drain of the drive transistor _ds 。

The driving transistor has a source and a drain, wherein the source is input with a power supply voltage, the drain is input with a reference voltage, and a voltage difference V between the source and the drain of the driving transistor _ds Is controlled by the power supply voltage and the reference voltage, so that the voltage difference V can be regulated by fixing the reference voltage and regulating the power supply voltage, or fixing the power supply voltage and regulating the reference voltage, or regulating the power supply voltage and the reference voltage simultaneously _ds 。

In some embodiments, the obtaining the brightness of the image currently displayed by the self-luminous display includes: and acquiring a display brightness value of the image currently displayed by the self-luminous display.

The brightness of the image displayed by the self-luminous display is represented by the display brightness value, that is, the brightness of the image in this embodiment refers to the overall brightness of the image, which reflects the condition of darkness of the whole screen, and the condition of darkness of the whole screen affects the conspicuity degree of bright spots.

In some embodiments, the obtaining the load current required for the self-luminous display to currently display an image includes: and calculating the load current according to the image data corresponding to the currently displayed image.

The load current required by a self-luminous display is different when displaying different image contents. While the image content may be embodied by image data, which in this embodiment comprises gray scale information for each sub-pixel within the self-emissive display. The current required for each sub-pixel can be estimated from these gray scale information, thereby obtaining the load current required for displaying the entire frame of image. In this way, only the calculation process needs to be added, the calculation accuracy is high, and no additional hardware structure is needed.

In some embodiments, the self-luminous display includes a display module and an application processor electrically connected to the display module, and the obtaining the load current required by the self-luminous display to display the image currently includes: and calculating the load current by detecting the node voltage between the display module and the application processor and combining the wiring impedance between the display module and the application processor.

The calculation of the load current in this embodiment is achieved by voltage and impedance. After the self-luminous display is assembled, the impedance of each wire, such as the wire between the display module and the application processor, is determined, and the load current required by the self-luminous display to display a frame of image can be calculated by detecting the node voltage of the detection point on the wire and combining the impedance of the wire. The manner of calculating the load current in this embodiment is less accurate than the manner of calculating by image data, but is easier to implement.

In some embodiments, the voltage difference V between the source and the drain of the driving transistor is adjusted according to the image brightness and the load current _ds Comprising: when the image brightness is confirmed to be larger than a preset brightness value, the voltage difference V between the source electrode and the drain electrode of the driving transistor is regulated according to the image brightness and the load current _ds 。

The self-luminous display has bright and dark images, when the brightness is high, the problem of bright spots hardly exists or the bright spots are not obvious, the influence on the whole display effect of the image is small, and when the brightness is low, if the bright spots appear, the effect on the display effect of the image is obvious. Thus, in this embodiment, a preset brightness value is set, and when the brightness of the acquired image is greater than the preset brightness value, the self-luminous display is considered to display an image with low brightness, and the adjustment of the voltage difference V is performed _ds The method is beneficial to reducing the power consumption and the calculated amount, and can also ensure that the technical problem of bright spots is effectively solved.

In some embodiments, the self-luminous display is operated in a plurality of display modes in a time-sharing manner, and the brightness ranges of images which can be displayed by the self-luminous display in different display modes are different; said adjusting a voltage difference V between a source and a drain of said driving transistor according to said image brightness and said load current _ds Comprising: when the brightness of the image is confirmed to be smaller thanWhen the brightness value is equal to the preset brightness value, the voltage difference V between the source electrode and the drain electrode of the driving transistor is switched according to the display mode _ds To different values.

When the brightness of the image is less than or equal to the preset brightness value, the image with high brightness displayed by the self-luminous display is considered to be a bright spot, and the bright spot problem is not obvious at the moment, and a relatively simple voltage difference V can be adopted _ds The adjustment mode. In this embodiment, the simple adjustment method is to adjust the voltage difference V according to different display modes of the self-luminous display _ds . This can improve the bright spot problem when displaying a high-luminance image on the basis of reducing the amount of calculation and reducing power consumption.

In some embodiments, the voltage difference V between the source and the drain of the driving transistor is adjusted according to the image brightness and the load current _ds Comprising: when the image brightness is less than or equal to the preset brightness value, the voltage difference V between the source electrode and the drain electrode of the driving transistor is regulated according to the image brightness _ds 。

In this embodiment, the simple adjustment method is to adjust the voltage difference V according to the display brightness of the self-luminous display _ds This can improve the bright spot problem when displaying a high-luminance image on the basis of reducing the calculation amount, reducing the power consumption, regardless of the load current.

In some embodiments, different image brightness corresponds to different voltage differences V _ds And different load currents correspond to different voltage differences V _ds 。

In this embodiment, the voltage difference V _ds The values of (2) and the values of the image brightness and the load current are all linearly related, which is advantageous to adopt different voltage differences V as much as possible according to the image content _ds 。

In some embodiments, the driving method further comprises: defining a plurality of brightness value intervals and a plurality of current value intervals; voltage difference V corresponding to image brightness in the same brightness value interval _ds The same, the voltage difference V corresponding to the image brightness in different brightness value intervals _ds Different fromThe method comprises the steps of carrying out a first treatment on the surface of the Voltage difference V corresponding to load current in the same current value interval _ds The same voltage difference V corresponding to the current brightness in different current value intervals _ds Different.

In this embodiment, a plurality of brightness value intervals and current value intervals are defined so that the voltage difference V corresponding to the values located in the same interval _ds The same, not only the image brightness or only the value of the load current changes by the voltage difference V _ds Changes occur which is advantageous in ensuring that the voltage difference V is adjusted according to the image content _ds On the basis of (a), the calculated amount is reduced.

A second aspect of the present application provides a display driving chip comprising a memory and a processor, the memory storing a computer program which, when executed by the processor, implements a display driving method as claimed in any one of the preceding claims.

The display driving chip can realize the same beneficial effects as the driving method.

A third aspect of the present application provides a display module, including a display panel and a display driving chip as described above that are electrically connected to each other, where the display driving chip is configured to drive the display panel to display an image.

The display module can realize the same beneficial effects as the driving method.

A fourth aspect of the present application provides an application processor for use in a self-emissive display, the application processor comprising a memory and a processor, the memory storing a computer program which when executed by the processor implements a display driving method as described above.

The application processor can realize the same beneficial effects as the driving method.

The fifth aspect of the present application provides a self-reflection display, including a display module and an application processor as described above, where the application processor is electrically connected to the display driving chip and configured to output image data to the display driving chip, so that the display driving chip drives the display panel to display an image according to the image data.

The self-reflection display can realize the same beneficial effects as the driving method.

The sixth aspect of the present application provides a self-luminous display, including a display module and an application processor as described above, where the display module includes a display panel and a display driving chip, and the application processor is electrically connected to the display driving chip and configured to output image data to the display driving chip, so that the display driving chip drives the display panel to display an image according to the image data.

The self-luminous display can realize the same beneficial effects as the driving method.

Drawings

Fig. 1 is a schematic block diagram of a self-luminous display according to an embodiment of the present application.

Fig. 2 is a schematic diagram of a part of a pixel driving circuit according to an embodiment of the present application.

Fig. 3 is a graph showing the variation of the source-drain current of the driving transistor with the source-drain voltage difference.

Fig. 4 is a flow chart of a driving method according to an embodiment of the present application.

Fig. 5 is a schematic structural diagram of a self-luminous display according to an embodiment of the present application for displaying a full black screen.

Fig. 6 is a schematic structural diagram of a self-luminous display according to an embodiment of the present application.

Fig. 7 is a schematic structural diagram of a self-luminous display displaying a gray-scale image according to an embodiment of the present disclosure.

Fig. 8 is a schematic structural diagram of a self-luminous display displaying a color picture according to an embodiment of the present application.

Fig. 9 is a schematic structural diagram of a self-luminous display according to an embodiment of the present application.

Fig. 10 is a flow chart of a driving method according to a modified embodiment of the present application.

Description of the main reference signs

Detailed Description

Embodiments of the present application are described below with reference to the accompanying drawings in the embodiments of the present application.

Referring to fig. 1, the self-luminous display 1 of the present embodiment includes a display module 10 and an application processor (Application Processor, AP) 20. The display module 10 includes a display panel 100 and a display driving chip (Display Driver Integrated Circuit, DDIC) 200, and the ap20 is electrically connected to the DDIC200.

The AP20 is located on the main board of the self-luminous display 1 as a main control device of the self-luminous display 1. The DDIC200 is integrated with the display module 10, and is used for controlling the display module 10 to display images. In operation of the self-luminous display 1, the AP20 is configured to output image data to the DDIC200, and the DDIC200 is configured to drive the light emitting elements in the respective sub-pixels of the display panel 100 to emit light of corresponding colors and brightness according to the image data so as to display an image.

The self-luminous display 1 is, for example, an organic light emitting diode (Organic Light Emitting Diode, OLED) display, a Micro light emitting diode (Micro Light Emitting Diode, micro LED) display, or the like, and may be a portable intelligent terminal, a display, an outdoor display screen, or the like.

Fig. 2 shows a partial structure of a pixel driving circuit in the display module 10, the pixel driving circuit including a driving transistor N1, a source S of the driving transistor N1 for inputting a power supply voltage ELVDD, and a drain D for inputting a common voltage ELVSS. The voltage difference between the source S and the drain D of the driving transistor N1 is denoted as V _ds The current between the source S and the drain D is denoted as I _ds . Fig. 3 shows the source-drain current I of the driving transistor N1 _ds With voltage difference V _ds Is a change curve of (a). As can be seen from fig. 3, after the driving transistor N1 enters the saturation region, the voltage difference V _ds Rise of current I _ds No acoustic changes will occur. If the driving transistor is not operated in the saturation regionCurrent I _ds Will follow the voltage difference V _ds Is increased by the rise of (a).

In order to meet the high luminance requirement of the self-light emitting display 1, it is necessary to increase the voltage across the power supply voltage ELVDD and the common voltage ELVSS (also referred to as IR drop) within the self-light emitting display 1. However, after the voltage across the transistor increases, the driving transistor N1 will no longer operate in the saturation region, current I _ds Will follow the voltage difference V _ds Is increased to cause unevenness and color shift when the self-luminous display 1 displays an image. To address the problem of non-uniformity and color shift, one approach is to reduce the value of the reference voltage ELVSS, e.g., from-3.5 to-4.5. However, when the self-light emitting display 1 displays a low-luminance screen (for example, a full black screen) after the value of the reference voltage ELVSS is reduced, bright spots easily occur in the image due to an increase in the cross voltage, which results in a large increase in the production yield of the self-light emitting display 1.

That is, in the case where the high brightness requirement of the self-luminous display 1 is satisfied, a problem of a bright point occurs again.

The embodiment of the application provides a driving method applied to a self-luminous display 1, which adjusts a voltage difference V in real time according to the image content displayed by the self-luminous display 1 _ds The driving transistor N1 is controlled to always work in the saturation region, so that the source-drain current I can be effectively avoided _ds With voltage difference V _ds Increase and increase, thereby avoiding source-drain current I _ds The increase produces bright spot, has solved the aforesaid technical problem that produces bright spot.

Referring to fig. 4, the driving method includes:

step S1, obtaining image content currently displayed by the self-luminous display, wherein the image content comprises image brightness currently displayed by the self-luminous display and load current required by displaying an image;

step S2, adjusting the voltage difference V between the source and the drain of the driving transistor according to the image brightness and the load current _ds To keep the drive transistor operating in the saturation region.

In step S1 of the present embodiment, the image content is specific content of a screen displayed by the self-luminous display, for example, the image content is an all-black screen shown in fig. 5, an all-white screen shown in fig. 6, a gray-scale screen shown in fig. 7, a color screen shown in fig. 8, or the like.

In the self-luminous display 1 of the present embodiment, the image content is represented by the image brightness and the load current required for displaying the image. I.e. different image contents correspond to different image brightness and different load currents. Step S1 therefore comprises in particular: and acquiring the brightness of the image currently displayed by the self-luminous display and the load current required for displaying the image.

In the present embodiment, the image luminance refers to the overall luminance of the entire screen displayed by the self-luminous display 1, that is, the overall luminance of the screen of the self-luminous display 1 for displaying the screen, characterized by the display luminance value (display brightness value, DBV). Different DBVs correspond to different image brightnesses. For example, in case of darker ambient light, a smaller DBV is output, the image brightness is turned down so as to save power consumption, and in case of brighter ambient light, a larger DBV is output, the image brightness is turned up so as to make the human eye observe the image better.

In the present embodiment, the load current is calculated from the image data.

In this embodiment, the image data includes a gray level for each sub-pixel in an image. According to the gray scale required to be displayed by each sub-pixel, the driving current required by each sub-pixel can be calculated, so that the load current required by the whole sub-pixels for displaying one frame of image can be obtained. The load current calculated in this way has higher accuracy, which makes the image content obtained from the load current more accurate.

In some other embodiments of the present application, the load current may also be obtained by other means.

Referring to fig. 9, the self-luminous display further includes a power module 30, and the power module 30 is also located on a motherboard (not shown) of the self-luminous display. The display module 10 is electrically connected to the power module 30, and the power module 30 is used for providing the reference voltage ELVDD to the display module 10. The display module 10 is electrically connected with the power module 30 through a wiring 40. A detection point P is disposed on the trace 40, and the voltage of the detection point P is detected by the DDIC200 in the display module 10. The impedance of the trace 40 is known and unchanged, and the current on the trace 40 (i.e., the load current) is known according to the reference voltage ELVDD, the voltage at the detection point P, and the impedance of the trace 40.

In the embodiment shown in fig. 9, the accuracy of the manner of obtaining the load current is lower than that of the manner of obtaining the load current in the present embodiment, but the technical solution is easier to implement, and a functional module for newly collecting the voltage at the detection point P may be added in the DDIC200.

The step S2 of this embodiment specifically includes: adjusting a voltage difference V between a source and a drain of the driving transistor according to the image brightness and the load current _ds 。

In this embodiment, the driving transistor is a P-type metal oxide semiconductor field effect transistor (positive channel Metal Oxide Semiconductor Transistor, PMOS), the source electrode inputs the power voltage ELVDD, the drain electrode inputs the reference voltage ELVSS, V _ds =elvdd- (elvss+voled), where VOLED is the difference in the voltages of the cathodes and anodes of the light emitting elements in the subpixels.

In some comparative examples, the reference voltage ELVSS is not changed by the change of the image content, and is maintained at-4.5V regardless of whether a full black picture, a full white picture, a gray-scale picture, or a complex color picture is displayed, for example.

In the present embodiment, the power voltage ELVDD is fixed, and the voltage difference V is adjusted by adjusting the reference voltage ELVSS _ds . For example, when the displayed image is a full black image as shown in fig. 5, detecting that the current reference voltage ELVSS is-4.5V, and adjusting it to-2.5V; when the displayed image is the full white picture shown in FIG. 6, detecting that the current reference voltage ELVSS is-4.1V, and adjusting the ELVSS to-4.5V; when the displayed image is the gray-scale image shown in FIG. 7, detecting that the current reference voltage ELVSS is-4.45V, and adjusting the ELVSS to-3V; when the displayed image is a complex color picture as shown in FIG. 8, the current reference voltage ELVSS is detected as-4.4V, and the ELVSS is adjusted to-4V.

In some embodiments of the present application, a reference voltage may also be setELVSS is fixed and voltage difference V is regulated by regulating power supply voltage ELVDD _ds . In other embodiments of the present application, the voltage difference V can also be adjusted by adjusting the power voltage ELVDD and the reference voltage ELVSS simultaneously _ds 。

The self-luminous display 1 of the above embodiment of the present application includes a pixel driving circuit including a driving transistor N1, the driving transistor N1 being used to drive light emitting elements (e.g., OLED, micro LED) in respective sub-pixels in the self-luminous display 1 to emit light. The driving transistor N1 has a source S and a drain D, and a voltage difference between the source S and the drain D is denoted as V _ds The current is denoted as I _ds . According to the operation characteristics of the driving transistor N1, when the driving transistor N1 operates in the saturation region, the voltage difference V _ds The rise does not cause current I _ds Is a variation of (c). However, in order to satisfy the highlight requirement of the self-luminous display 1, it is necessary to increase the voltage difference V _ds . With voltage difference V _ds The driving transistor N1 will no longer operate in the saturation region and the voltage difference V _ds An elevation will result in I _ds Enlargement, I _ds When the display is enlarged, bright spots are likely to occur when the self-luminous display 1 displays a dark screen. The driving method of the embodiment of the present application can adjust the voltage difference V in real time according to the image content displayed by the self-luminous display 1 _ds Avoiding voltage difference V _ds Rise too high to make the driving transistor N1 always operate in the saturation region, thus the voltage difference V _ds The rise does not cause current I _ds This can avoid the occurrence of bright spots in a low-luminance screen while also ensuring the high-luminance display requirement of the self-luminous display 1.

In the present embodiment, the image content mainly includes image brightness and load current, and the voltage difference V is adjusted _ds By adjusting the reference voltage ELVSS. Therefore, according to the driving method, the reference voltage ELVSS can be adjusted in real time according to the image brightness and the load current, so that the driving transistor N1 always keeps operating in the saturation region.

In the present embodiment, the image content (including the DBV and the value of the load current) and the voltage difference V _ds Is in one-to-one correspondence andi.e. different image contents, i.e. corresponding to different voltage differences V _ds 。

In a modified embodiment, the different image contents with smaller differences correspond to the same voltage difference V _ds Different image contents with larger difference correspond to different voltage differences V _ds 。

In this modified embodiment, a plurality of luminance value sections and a plurality of current value sections are defined, each luminance value section corresponding to a different value of DBV, and each current value section corresponding to a different value of load current. Different DBVs located in the same brightness value interval correspond to the same voltage difference V _ds Different load currents in the same current value interval correspond to the same voltage difference V _ds DBV in different brightness value range corresponds to different voltage difference V _ds The load currents in different current value intervals correspond to different V _ds . That is, in the modified embodiment, if the DBV of the two frame images is not the same, but the DBV of the two frame images is located in the same brightness value section, the voltage difference V is obtained when the two frame images are displayed _ds The values of (2) are the same; similarly, if the load currents of the two images are not the same, but the load currents of the two images are within the same current value interval, the voltage difference V is obtained when the two images are displayed _ds The values of (2) are the same.

In other words, in the modified embodiment, the voltage difference V is not necessarily set due to the difference of DBV or load current _ds Is different in value. If the DBVs of the two frames are different but located in the same brightness value interval, the difference between the DBVs of the two frames is considered to be smaller, and the voltage difference V can be not switched _ds Is a value of (2); if the load currents of the two frames are different but located in the same negative current section, the difference between the load currents of the two frames is considered to be small, or the voltage difference V does not need to be switched _ds Is a value of (2). This is advantageous in achieving switching of the voltage difference V in dependence of the image content (including the values of DBV and load current) _ds On the basis of the values of (2), the calculation amount is also reduced to a certain extent, and the picture quality problem or the flicker problem caused by frequently adjusting the reference voltage ELVSS can also be improved.

In another modified embodiment of the present application, the self-luminous display 1 does not always perform the above steps S1 and S2 when displaying an image.

Referring to fig. 10, in this modified embodiment, step S3 is further included before step S2: judging whether the current image brightness is larger than a preset brightness value.

If yes, executing step S2; if no in step S3, step S4 is executed: switching a voltage difference V between a source and a drain of the driving transistor according to the display mode _ds To different values; or, adjusting the voltage difference V between the source and the drain of the driving transistor according to the image brightness _ds 。

In this modified embodiment, the DBV that can be displayed by the self-luminous display 1 includes 4096 steps. The preset luminance value may be set to be equal to or greater than the DBV of the intermediate steps (2048, 2049 steps). When the detected brightness of the image (i.e., DBV) is greater than the preset brightness value, the voltage difference V is adjusted in the foregoing manner _ds 。

In this modified embodiment, the self-luminous display 1 has three display modes: normal mode, HBM mode, AOD mode. The Normal mode is the most commonly used display mode of the self-luminous display 1. The HBM mode is a display mode when the ambient light is high, and can be operated when the self-luminous display 1 is in an environment where sunlight is strong, for example. The AOD mode is a screen-off display mode in which, for example, when the self-luminous display 1 is in a charged state, the self-luminous display 1 is displayed as a black screen as a whole, and information such as date, time, and the like is displayed only in a small range portion.

When the detected brightness of the image is less than or equal to the preset brightness value, step S4 is executed, and the voltage difference V is switched according to different display modes _ds To different values. That is, when the detected image brightness is equal to or less than the preset brightness value, the voltage difference V is only different in the display mode _ds If the two images displayed by the self-luminous display 1 have different image contents, but are displayed in the same display mode, the voltage difference V is displayed _ds Are all identical.

Or, when the detected image brightness is less than or equal to the preset brightness value, step S4 is performed to adjust the voltage difference V according to the image brightness _ds . I.e. voltage difference V only when the image brightness differs _ds Is different regardless of the load current.

From the above, it can be seen that the adjustment V described in step S4 _ds In comparison with the adjustment V described in step S2 _ds The method is simpler, but when DBV is smaller than the preset brightness value, the effect of bright spots is smaller, so when DBV is smaller than the preset brightness value, the voltage difference V is switched according to different display modes _ds To different values, or to adjust the voltage difference V in dependence on the brightness of the image _ds The effect of avoiding the bright spots can be realized.

Since the bright spot problem is more pronounced when the DBV is higher, this modified embodiment adjusts V only when the DBV is greater than the preset brightness value _ds This is advantageous in achieving switching of the voltage difference V in dependence of the image content (including the values of DBV and load current) _ds On the basis of the values of (2), the calculation amount is also reduced to a certain extent, and the picture quality problem or the flicker problem caused by frequently adjusting the reference voltage ELVSS can also be improved.

In some embodiments of the present application, the above method steps are performed by DDIC 200; in other embodiments of the present application, the above method steps are performed by the AP 20; in other embodiments of the present application, the method steps described above may also be performed jointly by DDIC200 and AP 20.

The DDIC200 and the AP20 of the present embodiment include a memory and a processor, respectively. The memory may comprise a high speed RAM memory or may further comprise a non-volatile memory NVM, such as at least one magnetic disk memory, in which various instructions may be stored for performing various processing functions and implementing all of the method steps described herein. In an embodiment of the present application, the memory is configured to store computer executable program codes, where the program codes include instructions; the instructions, when executed by the processor, cause the processor to perform the processing actions described above in the method embodiments.

The processor mentioned in any of the above may be a general purpose Central Processing Unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the wireless communication method of the above first aspect.

In the device embodiment drawings provided in the application, the connection relation between the modules indicates that communication connection exists between the modules, and the connection relation can be specifically implemented as one or more communication buses or signal lines. Those of ordinary skill in the art will understand and implement the present invention without undue burden.

From the above description of the embodiments, it will be apparent to those skilled in the art that the present application may be implemented by means of software plus necessary general purpose hardware, or of course may be implemented by dedicated hardware including application specific integrated circuits, dedicated CPUs, dedicated memories, dedicated components and the like. Generally, functions performed by computer programs can be easily implemented by corresponding hardware, and specific hardware structures for implementing the same functions can be varied, such as analog circuits, digital circuits, or dedicated circuits. However, a software program implementation is a preferred embodiment in many cases for the present application. Based on such understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a readable storage medium, such as a floppy disk, a usb disk, a removable hard disk, a Read-Only Memory (ROM), a random-access Memory (RAM, random Access Memory), a magnetic disk or an optical disk of a computer, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method described in the embodiments of the present application.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product.

The computer program product includes one or more computer instructions. When loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present application, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by a wired (e.g., coaxial cable, fiber optic, digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be stored by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid State Disk (SSD)), etc.

It will be appreciated by persons skilled in the art that the above embodiments have been provided for the purpose of illustration only and not as a definition of the limits of the present application, and that appropriate modifications and variations of the above embodiments are within the scope of the invention as claimed.

Claims

1. A driving method applied to a self-luminous display including a pixel driving circuit for driving each sub-pixel in the self-luminous display to display an image, the pixel driving circuit including a driving transistor having a source and a drain;

the display driving method is characterized by comprising the following steps:

acquiring the image content currently displayed by the self-luminous display, wherein the image content comprises the image brightness currently displayed by the self-luminous display and the load current required by displaying the image;

regulating the voltage difference V between the source and drain of the driving transistor according to the image brightness and the load current _ds To keep the drive transistor operating in the saturation region.

2. The driving method according to claim 1, wherein a source of the driving transistor inputs a power supply voltage of the self-luminous display and a drain inputs a reference voltage of the self-luminous display;

the voltage difference V between the source and the drain of the driving transistor is regulated _ds Comprising:

adjusting the value of the supply voltage and/or the reference voltage, thereby adjusting the voltage difference V between the source and drain of the drive transistor _ds 。

3. The driving method according to claim 1 or 2, wherein the obtaining the brightness of the image currently displayed by the self-luminous display includes:

and acquiring a display brightness value of the image currently displayed by the self-luminous display.

4. A driving method according to any one of claims 1 to 3, wherein the obtaining a load current required for the self-luminous display to currently display an image includes:

and calculating the load current according to the image data corresponding to the currently displayed image.

5. A driving method according to any one of claims 1 to 3, wherein the self-luminous display includes a display module and a power module electrically connected to the display module, the display module and the power module are electrically connected by a wire, the wire has a detection point, and the obtaining the load current required for the self-luminous display to currently display an image includes:

and calculating the load current required by the self-luminous display for displaying the image currently by detecting the voltage of the detection point and combining the impedance of the wiring.

6. The driving method according to any one of claims 1 to 5, wherein the voltage difference V between a source and a drain of the driving transistor is adjusted according to the image brightness and the load current _ds Comprising:

when the image brightness is confirmed to be larger than a preset brightness value, the voltage difference V between the source electrode and the drain electrode of the driving transistor is regulated according to the image brightness and the load current _ds 。

7. The driving method according to claim 6, wherein the self-luminous display is operated in a plurality of display modes in a time-sharing manner, and the self-luminous display has different image brightness ranges which can be displayed in different display modes;

said adjusting a voltage difference V between a source and a drain of said driving transistor according to said image brightness and said load current _ds Comprising:

when the image brightness is less than or equal to the preset brightness value, the voltage difference V between the source electrode and the drain electrode of the driving transistor is switched according to the display mode _ds To different values.

8. The driving method according to claim 6, wherein the voltage difference V between the source and the drain of the driving transistor is adjusted according to the image brightness and the load current _ds Comprising:

when the image brightness is less than or equal to the preset brightness value, the voltage difference V between the source electrode and the drain electrode of the driving transistor is regulated according to the image brightness _ds 。

9. A driving method according to any one of claims 1-5, characterized in that different image brightnesses correspond to different voltage differences V _ds And different load currents correspond to different voltage differences V _ds 。

10. The driving method according to any one of claims 1 to 5, characterized by further comprising:

defining a plurality of brightness value intervals and a plurality of current value intervals;

voltage difference V corresponding to image brightness in the same brightness value interval _ds The same, the voltage difference V corresponding to the image brightness in different brightness value intervals _ds Different;

voltage difference V corresponding to load current in the same current value interval _ds The same voltage difference V corresponding to the current brightness in different current value intervals _ds Different.

11. A display driver chip comprising a memory and a processor, the memory storing a computer program, wherein the computer program when executed by the processor implements the display driving method of any of claims 1-10.

12. A display module comprising a display panel and the display driving chip of claim 11 electrically connected to each other, wherein the display driving chip is used for driving the display panel to display an image.

13. An application processor for use in a self-emissive display, the application processor comprising a memory and a processor, the memory storing a computer program which, when executed by the processor, implements the display driving method of any of claims 1-10.

14. The self-luminous display is characterized by comprising the display module set as claimed in claim 12 and an application processor, wherein the application processor is electrically connected with the display driving chip and is used for outputting image data to the display driving chip so that the display driving chip drives the display panel to display images according to the image data.

15. The self-luminous display is characterized by comprising a display module and the application processor as claimed in claim 13, wherein the display module comprises a display panel and a display driving chip, and the application processor is electrically connected with the display driving chip and is used for outputting image data to the display driving chip so that the display driving chip drives the display panel to display images according to the image data.