Display driving method and circuit, chip and display device

Abstract

The invention discloses a display driving method and circuit, a chip and a display device. The display driving method comprises the following steps: receiving a line feed control signal, wherein the line feed control signal comprises a plurality of continuous pulse signals; the display driving method comprises the steps of generating a line feed instruction according to pulse signals of a line feed control signal, and displaying corresponding pixel lines according to the line feed instruction, and further comprises the steps of generating a frame change instruction according to count values of a plurality of pulse signals of the line feed control signal after a frame change control signal is received, and outputting a driving signal for the next frame of display picture according to the frame changing instruction. Bright and dark ripples and flicker of a shot picture can be eliminated.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and particularly to a display driving method, circuit, chip, and display device. Background Art

[0002] Currently, LED display panels have become one of the mainstream modern display technologies due to their advantages such as high brightness, high resolution, energy efficiency, seamless splicing, good viewing angles, and high reliability.

[0003] An LED display panel includes pixels arranged in an array. During display, these pixels are driven by progressive scanning for display. When scanning quickly, a complete image is presented to the human eye by utilizing the visual persistence effect of the human eye. Moreover, between two adjacent frames of display images, a frame interval is usually set, that is, a period of non-display time is set between two adjacent frames of images. By setting the frame interval, it is possible to avoid conflicts in the display data of two adjacent frames of display images, thereby ensuring the integrity of the image display.

[0004] When photographing an LED display panel, the camera captures pixels that are in the lit state and have sufficient luminous intensity during the exposure time. When the exposure period of the camera is different from or out of sync with the frame rate of the LED display panel video source, there may be a situation where the exposure period overlaps with the frame interval, causing bright and dark ripples in the captured image. Moreover, as the camera continues to expose, the overlapping time period between the exposure period and the frame interval may gradually shift, resulting in a flickering sensation in the image and affecting the photographing quality. Summary of the Invention

[0005] In view of the above problems, the purpose of the present application is to provide a display driving method, circuit, chip, and display device to eliminate the bright and dark ripples and flickering in the captured image.

[0006] According to one aspect of the present application, a display driving method is provided, which includes: receiving a line feed control signal, where the line feed control signal includes a plurality of consecutive pulse signals; generating a line feed instruction according to the pulse signals of the line feed control signal, and performing display on corresponding pixel rows according to the line feed instruction. The display driving method further includes: after receiving a frame change control signal, generating a frame change instruction according to the count value of the plurality of pulse signals of the line feed control signal, and outputting a driving signal for the next frame of display image according to the frame change instruction.

[0007] Optionally, each frame of the display image includes a plurality of sub-frames, and the display driving method further includes: dispersing the display data of each frame of display image according to a preset number of sub-frames.

[0008] Optionally, the display screen includes a first type of display screen and a second type of display screen. The actual number of sub - frames of the first type of display screen is less than that of the second type of display screen, and there is at least one first - type display screen between two adjacent second - type display screens.

[0009] Optionally, the actual number of sub - frames of the first type of display screen is n - 1, and the actual number of sub - frames of the second type of display screen is n. , Tf is a preset frame period, Tr is a line - scanning period, R is the number of pixel rows of the display panel, INT represents rounding down. Among them, n is also the preset number of sub - frames, n>1 and is an integer.

[0010] Optionally, the actual number of sub - frames of the first type of display screen is m, and the actual number of sub - frames of the second type of display screen is m + 1. , Tf is a preset frame period, Tr is a line - scanning period, R is the number of pixel rows of the display panel, INT represents rounding down. Among them, m is also the preset number of sub - frames, m≥1 and is an integer.

[0011] Optionally, the multiple pulse signals include a first pulse signal with a first pulse width and a second pulse signal with a second pulse width. The first pulse signal also represents the switching of pixel rows between frames. Generating a frame - switching instruction according to the count value of the line - switching control signal after receiving the frame - switching control signal includes: when displaying each sub - frame, counting the multiple pulse signals of the line - switching control signal to obtain the count value; and after receiving the frame - switching control signal, determining whether the count value corresponds to the number of pixel rows, and generating the frame - switching instruction when the count value corresponds to the number of pixel rows.

[0012] Optionally, the step of obtaining the count value further includes: determining whether a next pulse signal is detected after the count value corresponds to the number of pixel rows; and resetting the count value after detecting the next pulse signal.

[0013] Optionally, dispersing the display data of each frame of the display screen according to the preset number of sub - frames includes: dispersing the row - display data of each pixel row in each frame of the display screen to obtain the preset number of sub - frame row data; and allocating each sub - frame row data to the corresponding sub - frame serial number.

[0014] Optionally, the method of allocating each sub-frame line data to the corresponding sub-frame serial number includes the dichotomy method. When the product of the preset number of sub-frames and the sub-frame period is greater than the preset frame period, in each frame of the display screen, the sub-frame serial number increases with the display order of the sub-frames, and the sub-frame serial number is reset when the frame change control signal is received and the count value is equal to the number of pixel rows; when the product of the preset number of sub-frames and the sub-frame period is less than the preset frame period, in each frame of the display screen, the sub-frame serial number decreases with the display order of the sub-frames, and the sub-frame serial number is reset when the frame change control signal is received and the count value is equal to the number of pixel rows.

[0015] Optionally, when the product of the preset number of sub-frames and the sub-frame period is greater than the preset frame period, in the first type of display screen, the sub-frame line data corresponding to the largest sub-frame serial number is not displayed; when the product of the preset number of sub-frames and the sub-frame period is less than the preset frame period, in the second type of display screen, the sub-frame line data corresponding to the largest sub-frame serial number is repeatedly displayed in two sub-frames.

[0016] According to another aspect of the present application, a display driving circuit is provided, which includes: a control unit for receiving a line change control signal and a frame change control signal, the line change control signal including a plurality of consecutive pulse signals, the control unit is further configured to generate a line change instruction according to the pulse signal of the line change control signal, and generate a frame change instruction according to the count value of the line change control signal after receiving the frame change control signal; an output unit for driving the corresponding pixel row to display according to the line change instruction, or outputting a driving signal for the next frame of display screen according to the frame change instruction.

[0017] According to the third aspect of the present application, a chip is provided, which includes the driving circuit as described above.

[0018] According to the fourth aspect of the present application, a display device is provided, which includes: a display panel; and the chip as described above for providing a driving signal for the display panel.

[0019] The display driving method, circuit, chip, and display device of the present application generate continuous line change instructions according to the line change control signal with continuous pulse signals, so that the display panel is continuously scanned and displayed, and is not limited by whether the frame change control signal is received and interrupted, avoiding different exposure degrees of each pixel row caused by a black screen when waiting for the frame change control signal, thus the bright and dark ripples during camera shooting can be eliminated, which is beneficial to improving the shooting effect. At the same time, through the coordinated cooperation of the frame change control signal and the line change control signal, the frame change timing can be accurately positioned, avoiding display abnormalities caused by timing errors.

[0020] Further, when performing scanning display with a fixed sub-frame period, by adjusting the number of sub-frames in a partial display screen to compensate for the mismatch between the data transmission timing and the display timing of the display screen, abnormal display caused by the timing mismatch can be avoided, which is beneficial to improving the display stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Through the following description of the embodiments of the present invention with reference to the accompanying drawings, the above and other objects, features and advantages of the present invention will become clearer. In the drawings: Figure 1 A schematic structural diagram of a display device is shown; Figure 2 A schematic timing diagram of sub-frame driving is shown; Figure 3 A schematic structural diagram of a display driving circuit according to an embodiment of the present application is shown; Figure 4 Shown Figure 3 A schematic structural diagram of a buffer in Figure 5 Shown Figure 3 A schematic structural diagram of a pulse width modulation unit in Figure 6 Shown Figure 3 A working waveform diagram of the display driving circuit shown in some embodiments is shown; Figure 7 Shown Figure 3 A working waveform diagram of the display driving circuit shown in some other embodiments is shown; Figure 8 A schematic flowchart of a display driving method according to an embodiment of the present application is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The various embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. In each of the drawings, the same elements are denoted by the same or similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale.

[0023] Meanwhile, in this specification and the claims, certain terms are used to refer to specific components. Those of ordinary skill in the art should understand that manufacturers may use different terms to refer to the same component. This specification and the claims do not use the difference in names as a way to distinguish components, but use the difference in functions of components as the criterion for distinction.

[0024] It should be understood that in the following description, a "circuit" may include a single or multiple combined hardware circuits, programmable circuits, state machine circuits, and / or elements capable of storing instructions executed by the programmable circuits. When an element or circuit is said to be "connected to" another element or when an element or circuit is said to be "connected between" two nodes, it may be directly coupled or connected to the other element or there may be intermediate elements. The connection between elements can be physical, logical, or a combination thereof. In contrast, when an element is said to be "directly coupled to" or "directly connected to" another element, it means there are no intermediate elements between the two.

[0025] In addition, it should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the said element.

[0026] It should also be noted that in the various methods and processes of this application, the magnitude of the step numbers does not mean the order of execution, nor does it constitute any limitation on the implementation process of the embodiments of this application.

[0027] Figure 1 The schematic structural diagram of a display device is shown. Refer to Figure 1 , the display device is, for example, an LED display device, and includes a receiving card 10, a scan driving circuit 20, a data driving circuit 30, and a display panel 40.

[0028] The receiving card 10 is respectively connected to the scan driving circuit 20 and the data driving circuit 30, and is used to provide a first timing signal to the scan driving circuit 20 according to the image data and control signals provided externally, and provide a second timing signal and display data to the data driving circuit 30. The scan driving circuit 20 outputs a scan signal according to the first timing signal, and the data driving circuit 30 converts the display data into a driving signal and outputs it according to the second timing signal.

[0029] It should be noted that the above-mentioned first timing signal and second timing signal should be understood as the general term of a type of signal rather than a single signal. For example, the first timing signal may include a line feed control signal DCK and a register clock RCK provided to the scan driver circuit 20, etc. The second timing signal may include a reference clock DCLK, a line feed control signal Hsync, a frame change control signal Vsync, etc. provided to the data driver circuit 30. Among them, in a preferred embodiment, the frame change control signal Vsync is usually sent as an instruction signal LE, and pulse signals with different pulse widths in the instruction signal LE can represent, for example, the frame change control signal Vsync, a data latch instruction, a write register instruction, etc.

[0030] Furthermore, the line feed control signal DCK sent to the scan driver circuit 20 and the line feed control signal Hsync sent to the data driver circuit 30 should be adapted to each other, so that the scan driver circuit 20 and the data driver circuit 30 work together to achieve the progressive scan driving of the display panel.

[0031] The display panel 40 includes a plurality of pixel rows, a plurality of data lines, and a plurality of scan lines. Each pixel row further includes a plurality of pixels. Each pixel is connected to the data driver circuit 30 via a corresponding data line and is also connected to the scan driver circuit 20 via a corresponding scan line. Each pixel is turned on when the scan signal received via the scan line has an effective level, and displays according to the drive signal received via the data line.

[0032] In order to improve the refresh rate, it is preferable to adopt a sub-frame driving method to drive the display panel. That is, after dividing a frame of display picture into multiple sub-frames, each pixel row is sequentially driven to display the corresponding sub-frame row data within each sub-frame. Assume that the display panel includes s pixel rows, and each frame of display picture contains k sub-frames. Figure 2 The schematic timing diagram of sub-frame driving is shown, as Figure 2 shown, the entire display process of the i-th frame of display picture is: sequentially display the first row of the first sub-frame, the second row of the first sub-frame to the s-th row of the first sub-frame. The emission brightness of each pixel row during its corresponding row display stage corresponds to the sub-frame row data of that pixel row in the first sub-frame; then display the first row of the second sub-frame, the second row of the second sub-frame..., and so on, until all k sub-frames are displayed.

[0033] Figure 3 The schematic structural diagram of the display driving circuit according to the embodiment of the present application is shown. The display driving circuit of the present application can, for example, be used as the data driver circuit 30 in the above-mentioned display device. Refer to Figure 3 The display driving circuit may include: a shift register 31, a control unit 32, a buffer 33, a pulse width modulation unit 34, and an output unit 35.

[0034] Furthermore, Figure 4Shows Figure 3 A schematic structural diagram of the buffer 33 therein; Figure 5 Shows Figure 3 A schematic structural diagram of the pulse width modulation unit 34 therein. The display driving circuit of the present application will be introduced in detail below in combination with Figures 3 to 5 the following.

[0035] The control unit 32 receives an instruction signal LE and a line feed control signal Hsync.

[0036] The instruction signal LE can be a pulse signal including different pulse widths to carry different instruction data. For example, the control unit 32 decodes the instruction signal LE with a pulse width (i.e., the effective level width) of 3 reference clocks DCLK into a frame change control signal Vsync.

[0037] In a traditional data driving circuit, the control unit generates a frame change instruction according to the frame change control signal Vsync, and generates a line feed instruction according to the effective level of the line feed control signal Hsync. However, between adjacent frame change control signals Vsync, the number of effective levels of the line feed control signal Hsync is fixed, corresponding to the product of the number of sub-frames and the number of pixel rows on the display panel. After generating these fixed numbers of line feed instructions, the control unit stops generating line feed instructions until it receives the next frame change control signal Vsync and then resumes. During the stage without line feed instruction generation, the display panel displays a black screen. This black screen stage is usually referred to as the frame interval. When using a camera to photograph the display panel, if the exposure period of the shutter overlaps with the frame interval, it will cause bright and dark ripples in the imaging, and when shooting continuous pictures, there will be picture flickering.

[0038] To solve this problem, in the embodiments of the present application, the line feed control signal Hsync includes a plurality of consecutive pulse signals. The control unit 32 generates consecutive line feed instructions ROW according to the pulse signals of the line feed control signal Hsync to display the corresponding pixel rows. That is to say, the control unit 32 is not limited by whether it receives the frame change control signal Vsync to interrupt the sending of the line feed instruction ROW, and the display panel will not display a black screen due to the interruption of the line feed instruction ROW. Therefore, it is possible to avoid the bright and dark ripples and picture flickering caused by the overlap of the exposure period of the shutter and the frame interval when using a camera, which is beneficial to improving the shooting effect.

[0039] If the number of sub-frames and the sub-frame period of each frame of the display picture are the same, during the continuous scanning display process, it will cause the data transmission timing of the display picture to mismatch with the display timing, resulting in abnormal display.

[0040] To further solve this problem, in a preferred embodiment, the number of sub-frames actually displayed in a partial display screen can be adjusted to compensate for the mismatch between the data transmission timing and the display timing of the display screen. Specifically, the display screen includes a first type of display screen and a second type of display screen with different numbers of sub-frames actually displayed. Among them, the actual number of sub-frames of the first type of display screen is less than that of the second type of display screen, and there is at least one first type of display screen between two adjacent second type of display screens. When the sub-frame period is fixed, by adjusting the number of sub-frames actually displayed in a partial display screen to compensate for the timing mismatch, display anomalies caused by the timing mismatch can be avoided.

[0041] Continuous scanning display will also make the actual frame period of a frame of display screen different from the preset frame period. That is to say, the product of the number of sub-frames actually displayed in each frame of display screen and the sub-frame period is different from the preset frame period. If the frame change instruction Fr is still generated according to the frame change control signal Vsync, forced frame change during display will occur, resulting in screen tearing. Therefore, in a preferred embodiment, multiple pulse signals of the line change control signal Hsync can include a first pulse signal with a first pulse width and a second pulse signal with a second pulse width. The first pulse signal and the second pulse signal indicate different types of line change operations. For example, the first pulse signal is used to indicate the switching between two adjacent frames of display screens, that is, switching the last pixel row of the current frame of display screen to the first pixel row of the next frame of display screen. The second pulse signal is used to indicate the switching of pixel rows within the same frame of display screen. The control unit 32 generates the frame change instruction Fr according to the count value of the line change control signal after receiving the frame change control signal Vsync, so that the display driving circuit outputs a driving signal for the next frame of display screen according to the frame change instruction Fr. Through the coordinated cooperation of the frame change control signal Vsync and the line change control signal Hsync, the frame change timing can be accurately positioned, avoiding screen tearing caused by forced frame change when the frame change control signal Vsync arrives during continuous scanning display, which is beneficial to improving the stability of display.

[0042] Exemplarily, it can be to count multiple pulse signals of the line change control signal Hsync when displaying each sub-frame to obtain a count value. After receiving the frame change control signal Vsync, it is judged whether the count value is equal to the number of pixel rows, and the frame change instruction Fr is generated when the count value is equal to the number of pixel rows. That is to say, after detecting the frame change control signal Vsync and completing the display of the current display screen, the frame change instruction Fr is generated.

[0043] In the above example where the count value of the pulse signal being equal to the number of pixel rows is taken as one of the conditions for generating the frame change instruction Fr, correspondingly, it is necessary to reset the count value after the display of each sub-frame is completed. Specifically, whenever the count value corresponds to the number of pixel rows, it is determined whether the next pulse signal is detected, and the count value is reset when the next pulse signal is detected. For example, the count value can be reset when the frame change control signal Vsync is received and the first pulse signal is detected.

[0044] Further, taking the number of pixel rows as s as an example. In some embodiments, the correspondence between the above count value and the number of pixel rows can be that whenever the count value is s - 1, the count value is reset to 0 according to the next pulse signal. In still other embodiments, the correspondence between the above count value and the number of pixel rows can also be that whenever the count value is s, the count value is reset to 1 according to the next pulse signal.

[0045] After the frame change control signal is detected, the frame change instruction is generated based on the count value of the pulse signal. At this time, the first pulse signal can also be used as a check for the generation timing of the frame change instruction. Thereby further improving the accuracy of the timing.

[0046] The buffer 33 caches the display data in units of frames according to the frame change instruction Fr. When displaying each frame of the display screen, the display data of this display screen has been written into the buffer 33 and is read line by line.

[0047] Combined with Figure 4 , in the embodiments of the present application, the buffer 33 includes a first buffer area 33a and a second buffer area 33b. The buffer 33 performs ping-pong caching on the display data of the display screen in units of frames according to the selection signal SC. The selection signal SC has a first level and a second level. The selection signal SC jumps according to the last line change instruction of the current frame display screen. When the selection signal SC is at the first level, the display data of the current frame display screen is read line by line from the first buffer area 33a, and the display data of the next frame display screen is written into the second buffer area 33b; when the selection signal SC is at the second level, the display data of the current frame display screen is read line by line from the second buffer area 33b, and the display data of the next frame display screen is written into the first buffer area 33a. And so on, realizing the cross writing and reading of the first buffer area 33a and the second buffer area 33b, thereby improving the processing efficiency of the display data and ensuring the smoothness of the display screen.

[0048] The pulse width modulation unit 34 is used to generate a pulse width modulation signal PWM according to the read line display data.

[0049] Combined with Figure 5, in the embodiments of the present application, the pulse width modulation unit 34 includes a sub-frame counter 34a, a disaggregation module 34b, and a signal generation module 34c.

[0050] The sub-frame counter 34a is used to obtain the sub-frame numbers of each sub-frame in the current frame display screen. In some embodiments, the sub-frame counter 34a can count the line feed instruction ROW output by the control unit 32 to obtain the sub-frame number. The disaggregation module 34b obtains the sub-frame line data of the corresponding pixel rows in each sub-frame according to the read line display data. Specifically, the disaggregation module 34b disaggregates the line display data into multiple sub-frame line data according to a preset disaggregation algorithm, and distributes these sub-frame line data under the corresponding sub-frame numbers. The number of sub-frame line data is the same as the preset number of sub-frames, and the distribution method includes the dichotomy method. The signal generation module 34c provides a corresponding pulse width modulation signal PWM according to the sub-frame line data of each pixel row under the corresponding sub-frame number in the current sub-frame.

[0051] The output unit 35 provides a corresponding driving signal to the display panel according to the line feed instruction ROW and the frame change instruction Fr. Specifically, a corresponding driving current Iout is provided to each pixel according to the pulse width modulation signal PWM obtained under the corresponding line feed instruction ROW and frame change instruction Fr.

[0052] According to the display driving circuit of the present application, a continuous line feed instruction is generated according to the line feed control signal with a continuous pulse signal, so that the display panel performs continuous scanning display, and is not limited by whether a frame change control signal is received and the display is interrupted, avoiding different exposure degrees of each pixel row caused by a black screen during waiting for the frame change control signal. Therefore, bright and dark ripples during camera shooting can be eliminated, which is beneficial to improving the shooting effect. At the same time, through the coordinated cooperation of the frame change control signal and the line feed control signal, the frame change timing can be accurately positioned, avoiding display anomalies caused by timing errors.

[0053] Figure 6 shows Figure 3 The working waveform diagram of the shown display driving circuit in some embodiments. Among them, the frame change control signal Vsync has a width of, for example, 3 DCLKs, that is, the w3 signal shown in the figure. The first pulse width of the first pulse signal has a width of, for example, 12 DCLKs, that is, the w12 signal; the second pulse width of the second pulse signal has a width of, for example, 4 DCLKs, that is, the w4 signal.

[0054] Referring to the embodiments as Figure 6 shown, the actual number of sub-frames of the first type of display screen is n - 1, and the actual number of sub-frames of the second type of display screen is n. n > 1 and is an integer, and can be calculated with reference to the following formula (1): (1) Wherein, Tf is a preset frame period, that is, the time interval between two adjacent frame change control signals Vsync. This preset frame period can be determined by the frame rate of the video source. Tr is the line scan period, R is the number of pixel rows of the display panel, INT represents rounding down, and n is also the preset number of sub-frames in the above-mentioned scattering algorithm.

[0055] When obtaining the number of sub-frames n with reference to the above formula (1), the product of n and the sub-frame period is greater than the preset frame period. That is to say, the actual frame period of a single second-type display screen is greater than the preset frame period. To compensate for this timing deviation, in each first-type display screen, some sub-frames need to be skipped. Preferably, when allocating sub-frame line data by the dichotomy method, the sub-frame number increases with the display order of the sub-frames, and the sub-frame with the largest sub-frame number is not displayed. By way of example, taking a frame of a display screen being scattered into n sub-frames such as sub-frame 0, sub-frame 1... sub-frame n-1 as an example, in each first-type display screen, the sub-frame with the sub-frame number n-1 is not displayed.

[0056] Furthermore, the sub-frame counter 34a can obtain the sub-frame number according to the number of line change instructions ROW, that is, according to the number of pulse signals of the line change control signal Hsync. When the display panel includes S pixel rows, whenever the display driving circuit receives S pulse signals, that is, every time the control unit 32 generates S line change instructions ROW, the sub-frame counter 34a performs a count, and the sub-frame number is incremented by one. Until the control unit 32 receives the frame change control signal Vsync and the count value of the multiple pulse signals of the line change control signal Hsync corresponds to the number of pixel rows, the sub-frame counter 34a is reset to 0. As described above, during the display process of a frame of a display screen, the count value of the multiple pulse signals of the line change control signal Hsync is reset with the number of pixel rows as the period. By way of example, referring to Figure 6 , if the current frame display screen is a first-type display screen, that is, including n-1 sub-frames, the sub-frame counter 34a sequentially increments from 0 to n-2 and is reset to 0 when the next count value changes; if the current frame display screen is a second-type display screen, that is, including n sub-frames, the sub-frame counter 34a sequentially increments from 0 to n-1 and is reset to 0 when the next count value changes. In a preferred embodiment, the reset of the sub-frame counter 34a is performed according to the last line change instruction of each frame of the display screen, which can isolate the change of the sub-frame number and the switching of the sub-frames, and is beneficial to saving the computing resources of the driving circuit.

[0057] The selection signal CS can also jump according to the last line change instruction of the display screen. Similarly, it can also be that when the control unit 32 receives the frame change control signal Vsync and the count value of the multiple pulse signals of the line change control signal corresponds to the number of pixel rows, the control changes the level of the selection signal SC provided to the buffer 33.

[0058] Further, in order to reduce the computational burden of the data driving circuit, the preset number of sub-frames can be calculated by the receiving card 10 and sent to the driving circuit 30 along with the serial data SI. Exemplarily, after decoding the serial data, the shift register 31 sends the preset number of sub-frames to the pulse width modulation unit 34 via the control unit 32.

[0059] Figure 7 shows Figure 3 the working waveform diagram of the display driving circuit shown in some other embodiments. Similar to Figure 6 the embodiment shown, the frame change control signal Vsync has a width of 3 DCLKs, i.e., the signal w3 shown in the figure. The first pulse width of the first pulse signal has a width of, for example, 12 DCLKs, i.e., the signal w12 shown in the figure; the second pulse width of the second pulse signal has a width of, for example, 4 DCLKs, i.e., the signal w4 shown in the figure.

[0060] Different from Figure 6 the embodiment shown, in Figure 7 the embodiment shown, the actual number of sub-frames of the first type of display screen is m, and the actual number of sub-frames of the second type of display screen is m + 1. m ≥ 1 and is an integer, and can be calculated with reference to the following formula (2): (2) where Tf is the preset frame period, that is, the time interval between two adjacent frame change control signals Vsync. This preset frame period can be determined by the video source frame rate. Tr is the line scan period, R is the number of pixel rows of the display panel, INT represents rounding down, and m is also the preset number of sub-frames in the above splitting algorithm.

[0061] When obtaining the number of sub-frames m with reference to the above formula (2), the product of the preset number of sub-frames and the sub-frame period is less than the preset frame period. That is to say, the actual frame periods of a single first type of display screen and the second type of display screen are both less than the preset frame period. In order to further compensate for the timing deviation in display, in each second type of display screen, some sub-frames need to be repeatedly displayed. In some embodiments, when allocating sub-frame line data by the dichotomy method, the sub-frame with the largest sub-frame number is repeatedly displayed. Preferably, the sub-frame number decreases with the display order of the sub-frames, and after sequentially displaying m sub-frames, the sub-frame with the largest sub-frame number is repeatedly displayed in the last sub-frame. That is to say, taking the example of splitting a frame of display screen into m sub-frames such as sub-frame 0, sub-frame 1... sub-frame m - 1, in each second type of display screen, sub-frame m - 1, sub-frame m - 2 are sequentially displayed until after sub-frame 0 is displayed, sub-frame m - 1 is repeatedly displayed.

[0062] Further, similar to the above Figure 6Similar to the embodiments shown, it can be when the control unit 32 receives the frame conversion control signal Vsync, and the count value of the multiple pulse signals of the line feed control signal corresponds to the number of pixel rows, the sub-frame counter 34a is reset, and the level of the control selection signal SC jumps. However, different from the above Figure 6 shown embodiments, as described above, when the sub-frame data allocation method of the dichotomy is adopted in the disassembly module 34b, in order to further improve the display uniformity, in the Figure 7 shown embodiments, the sub-frame counter 34a adopts a counting method of reverse counting. That is to say, in the Figure 7 shown embodiments, the reset value of the sub-frame counter 34a corresponds to the preset number of sub-frames. The specific correspondence can be that when the minimum count value of the reverse counting of the sub-frame counter 34a is 0, the reset value of the sub-frame counter 34a is m - 1. Every time S line feed instructions are sent, the sub-frame counter is decremented by one until the count value of the sub-frame counter 34a is 0, indicating that m sub-frames are displayed.

[0063] It should be noted that for the above preferred embodiments, taking the example of splitting a frame of display screen into m sub-frames such as the 0th sub-frame, the 1st sub-frame... the (m - 1)th sub-frame, in each second type of display screen, the (m - 1)th sub-frame, the (m - 2)th sub-frame are sequentially displayed until after the 0th sub-frame is displayed, the (m - 1)th sub-frame is repeatedly displayed. When the current frame of the display screen is being displayed, the sub-frame counter 34a sequentially decreases from m - 1 to 0 and then resumes to m - 1. At this time, the sub-frame with the largest sub-frame number is repeatedly displayed. The count value remains m - 1 during the next count value change.

[0064] The present application also provides a chip, for example, including the above display driving circuit. The present application also provides a display device, including a display panel and the above chip.

[0065] According to the display driving circuit, chip and display device of the present application, continuous line feed instructions are generated according to the line feed control signal with continuous pulse signals, so that the display panel performs continuous scanning display, and is not limited by whether the frame conversion control signal is received and the display is interrupted, avoiding different exposure degrees of each pixel row caused by a black screen during waiting for the frame conversion control signal, thus the bright and dark ripples during camera shooting can be eliminated, which is beneficial to improving the shooting effect. At the same time, through the coordinated cooperation of the frame conversion control signal and the line feed control signal, the frame conversion timing can be accurately positioned, avoiding display abnormalities caused by timing errors.

[0066] Furthermore, when performing scanning display with a fixed sub-frame period, by adjusting the number of sub-frames in some display screens to compensate for the mismatch between the data transmission timing and the display timing of the display screen, display abnormalities caused by timing mismatch can be avoided, which is beneficial to improving the display stability.

[0067] Figure 8 A schematic flowchart showing the display driving method according to an embodiment of the present application. The display driving method provided by the present application can be implemented according to the above display driving circuit, for example. Refer to Figure 8 , the driving method provided by the present application includes: Step S11: Receive a line feed control signal, where the line feed control signal includes a plurality of consecutive pulse signals.

[0068] Step S12: Generate a line feed instruction according to the pulse signal of the line feed control signal, and perform display on the corresponding pixel rows according to the line feed instruction.

[0069] Since the pulse signals in the line feed control signal are consecutive, the generated line feed instructions are also consecutive. That is to say, the generation of the line feed instructions is not interrupted by whether a frame change control signal is received. The display panel will not display a black screen due to the interruption of the line feed instructions. Therefore, it is possible to avoid bright and dark ripples and screen flickering caused by the overlap of the shutter exposure period and the frame interval when using a camera to take pictures, which is beneficial to improving the shooting effect.

[0070] In some embodiments, the refresh rate is increased by splitting each frame of the display screen into multiple sub-frames for display. Correspondingly, the display driving method further includes dispersing the display data of each frame of the display screen according to a preset number of sub-frames. Specifically, it can be to disperse the line display data of each pixel row in a frame of the display screen to obtain a plurality of sub-frame line data, and allocate these sub-frame line data to the corresponding sub-frame serial numbers. Among them, the number of sub-frame line data is the same as the preset number of sub-frames, and the allocation method includes the dichotomy method.

[0071] However, if the number of sub-frames and the sub-frame period of each frame of the display screen are the same, during the continuous scanning display process, it will cause a mismatch between the data transmission timing and the display timing of the display screen, resulting in abnormal display. To further solve this problem, in a preferred embodiment, the number of sub-frames in some display screens can be adjusted to compensate for the mismatch between the data transmission timing and the display timing of the display screen. Specifically, the display screen includes a first type of display screen and a second type of display screen with different numbers of sub-frames. Among them, the actual number of sub-frames of the first type of display screen is less than that of the second type of display screen, and there is at least one first type of display screen between two adjacent second type of display screens. When the sub-frame period is fixed, the number of sub-frames in some display screens is adjusted to compensate for the timing mismatch, avoiding abnormal display caused by the timing mismatch.

[0072] Further, in some embodiments, the actual number of sub-frames of the first type of display screen is n - 1, and the actual number of sub-frames of the second type of display screen is n. n > 1 and is an integer, and can be calculated with reference to the above formula (1). At this time, n is also the preset number of sub-frames. Accordingly, the counting and resetting of the sub-frame numbers and the level control of the selection signal can also refer to the above description of Figure 6 .

[0073] In still other embodiments, the actual number of sub-frames of the first type of display screen is m, and the actual number of sub-frames of the second type of display screen is m + 1. m ≥ 1 and is an integer, and can be calculated with reference to the above formula (2). At this time, m is also the preset number of sub-frames. Accordingly, the counting and resetting of the sub-frame numbers and the level control of the selection signal can also refer to the above description of Figure 7 .

[0074] Continuous scanning display will also make the actual frame period of a frame of display screen different from the preset frame period. That is to say, the product of the actual number of sub-frames and the sub-frame period of each frame of display screen is different from the preset frame period. If the frame change instruction is still generated according to the frame change control signal, forced frame change will occur during the display, resulting in screen tearing. Therefore, in a preferred embodiment, the multiple pulse signals of the line change control signal Hsync may include a first pulse signal with a first pulse width and a second pulse signal with a second pulse width. The first pulse signal and the second pulse signal indicate different types of line change operations. For example, the first pulse signal is used to indicate the switching between two adjacent frames of display screens, that is, switching the last pixel row of the current frame of display screen to the first pixel row of the next frame of display screen. The second pulse signal is used to indicate the switching of pixel rows within the same frame of display screen. Accordingly, the display driving method provided in this application further includes the following steps S13 and S14.

[0075] Step S13, determine whether a frame change control signal is obtained, and execute step S14 when the frame change control signal is obtained.

[0076] Step S14, generate a frame change instruction according to the count value of the line change control signal, and output a driving signal for the next frame of display screen according to the frame change instruction.

[0077] Through the coordinated cooperation of the frame change control signal and the line change control signal, the frame change timing can be accurately positioned, avoiding screen tearing caused by forced frame change when the frame change control signal arrives during the continuous scanning display process, which is beneficial to improving the stability of the display.

[0078] Exemplarily, when each sub-frame is displayed, multiple pulse signals of the line feed control signal can be counted to obtain a count value. After receiving the frame change control signal, it is determined whether the count value is equal to the number of pixel rows, and a frame change instruction is generated when the count value is equal to the number of pixel rows. That is, after detecting the frame change control signal and completing the display of the current display screen, a frame change instruction is generated.

[0079] In the above example where the count value of the pulse signal being equal to the number of pixel rows is used as one of the conditions for generating the frame change instruction, correspondingly, the count value needs to be reset after the display of each sub-frame is completed. Specifically, whenever the count value corresponds to the number of pixel rows, it is determined whether the next pulse signal is detected, and the count value is reset when the next pulse signal is detected. For example, the count value can be reset when the frame change control signal is received and the first pulse signal is detected.

[0080] After detecting the frame change control signal, a frame change instruction is generated based on the count value of the pulse signal. At this time, the first pulse signal can also be used as a check for the generation timing of the frame change instruction. Thus, the accuracy of the timing can be further improved.

[0081] According to the display driving method of the present application, continuous line feed instructions are generated according to the line feed control signal with continuous pulse signals, so that the display panel is continuously scanned and displayed, and is not limited by whether the frame change control signal is received and interrupted in display. It avoids the different exposure degrees of each pixel row caused by the black screen during the waiting for the frame change control signal, so the bright and dark ripples during camera shooting can be eliminated, which is beneficial to improving the shooting effect. At the same time, through the coordinated cooperation of the frame change control signal and the line feed control signal, the frame change timing can be accurately positioned, avoiding display abnormalities caused by timing errors.

[0082] Furthermore, when scanning and displaying with a fixed sub-frame period, by adjusting the number of sub-frames in a partial display screen to compensate for the mismatch between the data transmission timing and the display timing of the display screen, display abnormalities caused by timing mismatch can be avoided, which is beneficial to improving the stability of the display.

[0083] It should be noted that the display driving method provided by the present application can be implemented by the display driving circuit provided by the present application. Although not described in detail, it should be understood that the display driving method provided by the present application may also include related steps to control the corresponding structures in the above display driving circuit to implement corresponding functions.

[0084] As described above with respect to the embodiments of the present application, these embodiments do not describe all the details in detail, nor do they limit the present application to only the specific embodiments. Obviously, many modifications and variations can be made according to the above description. These embodiments are selected and specifically described in this specification in order to better explain the principles and practical applications of the present application, so that those skilled in the art can make good use of the present application and its modifications based on the present application. The scope of protection of the present application shall be subject to the scope defined by the claims of the present application.

Claims

1. A display driving method, wherein, Including: Receiving a line feed control signal, where the line feed control signal includes a plurality of consecutive pulse signals; Generating a line feed instruction according to the pulse signals of the line feed control signal, and performing display on corresponding pixel rows according to the line feed instruction, wherein, the display driving method further includes: After receiving a frame change control signal, generating a frame change instruction according to the count value of the plurality of pulse signals of the line feed control signal, and outputting a driving signal for the next frame of display screen according to the frame change instruction.

2. The display driving method according to claim 1, wherein, Each frame of the display screen includes a plurality of sub-frames, the display driving method further includes: Scattering the display data of each frame of the display screen according to a preset number of sub-frames.

3. The display driving method according to claim 2, wherein, The display screen includes a first type of display screen and a second type of display screen, the actual number of sub-frames of the first type of display screen is less than the actual number of sub-frames of the second type of display screen, at least one of the first type of display screen is included between two adjacent second type of display screens.

4. The display driving method according to claim 3, wherein, The actual number of sub-frames of the first type of display screen is n - 1, and the actual number of sub-frames of the second type of display screen is n, ， Tf is a preset frame period, Tr is a line scanning period, R is the number of pixel rows of the display panel, INT represents rounding down, wherein, n is also the preset number of sub-frames, n > 1 and is an integer.

5. The display driving method according to claim 3, wherein, The actual number of sub-frames of the first type of display screen is m, and the actual number of sub-frames of the second type of display screen is m + 1, ， Tf is a preset frame period, Tr is a line scanning period, R is the number of pixel rows of the display panel, INT represents rounding down, wherein, m is also the preset number of sub-frames, m ≥ 1 and is an integer.

6. The display driving method according to claim 4 or 5, wherein, the plurality of pulse signals include a first pulse signal having a first pulse width and a second pulse signal having a second pulse width, and the first pulse signal also represents the switching of pixel rows between frames, the generating a frame change instruction according to the count value of the line feed control signal after receiving the frame change control signal includes: When displaying each sub-frame, counting the plurality of pulse signals of the line feed control signal to obtain the count value; and After receiving the frame change control signal, determining whether the count value corresponds to the number of pixel rows, and generating the frame change instruction when the count value corresponds to the number of pixel rows.

7. The display driving method according to claim 6, wherein, The step of obtaining the count value further includes: After the count value corresponds to the number of pixel rows, determining whether the next pulse signal is detected; and Resetting the count value after detecting the next pulse signal.

8. The display driving method according to claim 6, wherein, The scattering the display data of each frame of the display screen according to a preset number of sub-frames includes: Scattering the line display data of each pixel row in each frame of the display screen to obtain the preset number of sub-frame line data; Allocating each sub-frame line data to a corresponding sub-frame serial number.

9. The display driving method according to claim 8, wherein, The method of allocating each sub-frame line data to a corresponding sub-frame serial number includes the dichotomy method, When the product of the preset number of sub - frames and the sub - frame period is greater than the preset frame period, in each frame of the display screen, the sub - frame number increases with the display order of the sub - frames, and the sub - frame number is reset when the frame change control signal is received and the count value is equal to the number of pixel rows; When the product of the preset number of sub - frames and the sub - frame period is less than the preset frame period, in each frame of the display screen, the sub - frame number decreases with the display order of the sub - frames, and the sub - frame number is reset when the frame change control signal is received and the count value is equal to the number of pixel rows.

10. The display driving method according to claim 9, wherein, When the product of the preset number of sub - frames and the sub - frame period is greater than the preset frame period, in the first type of display screen, the sub - frame row data corresponding to the largest sub - frame number is not displayed; When the product of the preset number of sub - frames and the sub - frame period is less than the preset frame period, in the second type of display screen, the sub - frame row data corresponding to the largest sub - frame number is repeatedly displayed in two sub - frames.

11. A display driving circuit, wherein, Comprising: A control unit, configured to receive a line - feed control signal and a frame - change control signal, the line - feed control signal including a plurality of consecutive pulse signals, the control unit is further configured to generate a line - feed instruction according to the pulse signals of the line - feed control signal, and generate a frame - change instruction according to the count value of the line - feed control signal after receiving the frame - change control signal; An output unit, configured to drive the corresponding pixel rows to display according to the line - feed instruction, or output a driving signal for the next - frame display screen according to the frame - change instruction.

12. A chip, wherein, Comprising the driving circuit according to claim 11.

13. A display device, wherein, Comprising: A display panel; And The chip according to claim 12, configured to provide a driving signal for the display panel.

Images