Display driving method, display driving circuit and display device

Abstract

The invention provides a display driving method, a display driving circuit and a display device, and relates to the technical field of display, and the display driving method comprises the steps: when a first interval duration corresponding to a display signal meets a dynamic frequency switching condition, closing a sleep function, and providing a stable source driving voltage for a display panel in a vertical blanking stage of each frame; wherein the first interval duration is the latest interval duration of two adjacent switching frequencies of the display signal. Screen flicker of the display panel can be reduced, and the image quality of the display panel is improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display driving method, a display driving circuit and a display device. Background Art

[0002] Currently, the timing controller (TCON) will enable the sleep (Wake) function to reduce logic power consumption. After the Wake function is enabled, during the vertical blanking (V-Blank) phase within a frame, all output terminals of the source driver chip (Source IC) remain in a floating state, thereby reducing the power consumption of the display device.

[0003] In the scenario of dynamic frequency switching, the display signal will switch between high and low frequencies in a very short interval. If the TCON turns on the Wake function, all output ends of the Source IC will remain in the Floating state, which may cause the screen flicker problem to worsen, resulting in a poor flicker level of the display device during dynamic frequency switching. Summary of the invention

[0004] The present application provides a display driving method, a display driving circuit and a display device, which can solve the technical problem that the flicker level of the display device is poor due to turning on the wake function during dynamic frequency switching.

[0005] In a first aspect, the present application provides a display driving method, the display driving method comprising:

[0006] When the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, the sleep function is turned off, and a stable source driving voltage is provided to the display panel during the vertical blanking phase of each frame;

[0007] The first interval duration is the latest interval duration between two consecutive switching frequencies of the display signal.

[0008] Optionally, before turning off the sleep function, the display driving method further includes:

[0009] Detecting the frequency corresponding to the display signal of the current frame;

[0010] When the frequency of the current frame is different from the frequency of the previous frame, determining that the display signal switches the frequency once after the previous frame ends;

[0011] The interval duration between the current switching frequency and the last switching frequency is determined as the latest interval duration.

[0012] Optionally, determining the interval duration between the current switching frequency and the last switching frequency as the latest interval duration includes:

[0013] The total duration of all frames between the current switching frequency and the last switching frequency is determined as the latest interval duration.

[0014] Optionally, after turning off the sleep function, the display driving method further includes:

[0015] In the display phase of each frame, a data voltage corresponding to the display signal is provided to the display panel to drive the display panel to display a picture.

[0016] Optionally, the display driving method further includes:

[0017] When the first interval duration meets the static frequency condition, the sleep function is turned on, and the data voltage corresponding to the display signal is provided to the display panel during the display phase of each frame, and the target output terminal is kept in a suspended state during the vertical blanking phase of each frame; wherein the target output terminal is an output terminal connected to the data line of the display panel.

[0018] Optionally, the display driving method further includes:

[0019] When the first interval duration is greater than a preset duration threshold, determining that the first interval duration meets the dynamic frequency switching condition;

[0020] When the first interval duration is less than or equal to the preset duration threshold, it is determined that the first interval duration meets the static frequency condition.

[0021] In a second aspect, the present application provides a display driving circuit, the display driving circuit comprising: a timing control circuit and a source driving circuit;

[0022] The timing control circuit is connected to the source driving circuit and is configured to turn off the sleep function when the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, and send a first control signal to the source driving circuit in the vertical blanking phase of each frame;

[0023] The source driving circuit is configured to provide a stable source driving voltage to the display panel in response to the first control signal during the vertical blanking phase of each frame; wherein the first interval duration is the latest interval duration between two adjacent switching frequencies of the display signal.

[0024] Optionally, the timing control circuit is configured to send a second control signal to the source driving circuit during the display phase of each frame after turning off the sleep function;

[0025] The source driving circuit is configured to provide the display panel with a data voltage corresponding to the display signal in response to the second control signal during the display phase of each frame, so as to drive the display panel to display a picture.

[0026] Optionally, the timing control circuit is configured to start the sleep function when the first interval duration meets the static frequency condition, and send a third control signal to the source driving circuit in the display phase of each frame, and send a fourth control signal to the source driving circuit in the vertical blanking phase of each frame;

[0027] The source driving circuit is configured to respond to the third control signal during the display phase of each frame to provide the display panel with a data voltage corresponding to the display signal, and to respond to the fourth control signal during the vertical blanking phase of each frame to keep the output terminal connected to the data line of the display panel in a suspended state.

[0028] Optionally, the timing control circuit is configured to detect the frequency corresponding to the display signal of the current frame. When the frequency of the current frame is different from the frequency of the previous frame, it is determined that the display signal switches its frequency once after the end of the previous frame, and the interval duration between this switching frequency and the previous switching frequency is determined as the latest interval duration.

[0029] Optionally, the timing control circuit is configured to determine the total duration of all frames between the current switching frequency and the previous switching frequency as the latest interval duration.

[0030] Optionally, the timing control circuit is configured to determine that the first interval duration meets the dynamic frequency switching condition when the first interval duration is greater than a preset duration threshold, and to determine that the first interval duration meets the static frequency condition when the first interval duration is less than or equal to the preset duration threshold.

[0031] In a third aspect, the present application provides a display device, the display device comprising a display panel, and a display driving circuit as in the second aspect;

[0032] The source driving circuit in the display driving circuit is connected to the display panel.

[0033] A display driving method, a display driving circuit and a display device provided by the present application have at least the following advantages: the first interval duration is the latest interval duration between two adjacent switching frequencies of a display signal. When the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, the sleep function is turned off, and a stable source driving voltage is provided to the display panel during the vertical blanking phase of each frame. In this way, the screen flicker during dynamic frequency switching can be reduced, the screen flicker level of the display panel during dynamic frequency switching can be improved, and the image quality of the display panel can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1 is a schematic diagram of the steps of a display driving method provided in an embodiment of the present application;

[0036] Figure 2 is a structural schematic diagram of a display driving circuit provided in an embodiment of the present application;

[0037] Figure 3 is a driving flow chart of a display driving method provided in an embodiment of the present application;

[0038] Figure 4 is a timing diagram of a display driving method provided in an embodiment of the present application;

[0039] Figure 5 It is a schematic diagram of a signal waveform of a sleep function in the related art;

[0040] Figure 6 It is one of the test waveform diagrams of a display driving circuit provided in an embodiment of the present application;

[0041] Figure 7 This is a second test waveform diagram of a display driving circuit provided in an embodiment of the present application;

[0042] Figure 8 This is the third test waveform diagram of a display driving circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in some embodiments to clearly and completely describe the technical solutions in some embodiments. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] Figure 1 is a schematic diagram of the steps of a display driving method provided by an embodiment of the present application, such as Figure 1 As shown, the display driving method includes:

[0045] Step S1, when the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, the sleep function is turned off, and a stable source driving voltage is provided to the display panel during the vertical blanking phase of each frame;

[0046] The first interval duration is the latest interval duration between two consecutive switching frequencies of the display signal.

[0047] In some embodiments, a display driving method provided in this embodiment can be used to drive a display panel such as an organic light emitting diode display (OLED) or a liquid crystal display (LCD) to display a picture. For example, in a medium-sized or large-sized OLED display device, the display driving circuit can use the display driving method provided in this embodiment to drive the display panel. The display driving circuit or the timing control circuit in the display driving circuit can be used as the execution body of the display driving method of this embodiment.

[0048] In some embodiments, the display driving circuit can be connected to the host end of the display device to receive a display signal sent by the host end. The host end can switch the frequency of the display signal, and the display driving circuit performs frequency detection on the display signal after receiving the display signal. The host end can install dynamic frequency cutting software, and the technician can set parameters in the dynamic frequency cutting software. For example, the dynamic frequency cutting software can be set to switch from 4 frames of 30 Hz to 12 frames of 120 Hz and then switch to 4 frames of 30 Hz in turn for dynamic frequency cutting.

[0049] In some embodiments, when the interval between two adjacent switching frequencies of the display signal is very short, it can be determined that the front-end system of the host side performs dynamic frequency switching, otherwise the display signal is in a static frequency state. The static frequency state includes static high frequency and static low frequency. For example, the static high frequency is 120HZ and the static low frequency is 30HZ. It can be determined whether the display signal is currently in a dynamic frequency switching state or a static frequency state based on the length of the interval between the two most recent switching frequencies of the display signal.

[0050] In some embodiments, each time the display signal switching frequency is detected, the current switching frequency and the previous switching frequency are taken as two adjacent switching frequencies, and the interval between the current switching frequency and the previous switching frequency is the latest interval between the two adjacent switching frequencies, which is recorded as the first interval in this implementation.

[0051] In some embodiments, the dynamic frequency switching condition may be that the interval between the two most recent switching frequencies of the display signal does not exceed a preset duration threshold. If the first interval duration is less than or equal to the preset duration threshold, the first interval duration meets the dynamic frequency switching condition.

[0052] For example, the total duration of 4 frames of 30Hz display signal is 133 milliseconds (ms), and the total duration of 12 frames of 120Hz display signal is 100ms. If 4 frames of 30Hz are switched to 12 frames of 120Hz and then to 4 frames of 30Hz, the interval between two adjacent switching frequencies is 100ms. The preset duration threshold can be 150ms. Since 100ms is less than 150ms, 100ms meets the dynamic frequency switching condition.

[0053] In the related art, the sleep (Wake) function is to reduce the logic power consumption in the vertical blanking (V-Blank) stage. After the Wake function is turned on, all output terminals of the display driver circuit connected to the data lines of the display panel can be kept in a floating state. For example, in the V-Blank stage of each frame, all output terminals of the Source IC are in a floating state, thereby reducing the power consumption of the Source IC in the V-Blank stage. For example, after the Wake function is turned on, the power consumption corresponding to the 120Hz display signal of the white screen decreases by 1.2%, the power consumption corresponding to the 60Hz display signal decreases by 12.2%, and the power consumption corresponding to the 30Hz display signal decreases by 19%.

[0054] However, the output voltage in the floating state is unstable and susceptible to interference, which can easily lead to further deterioration of the flicker problem of the display panel screen, and in severe cases affect the display quality. At present, the flicker level of the display panel during dynamic frequency switching needs to meet the flicker test specifications, such as the frequency switching test with a high and low frequency interval of about 100ms, and the flicker value specification (Spec) is -60 decibels (db).

[0055] A display driving method provided in an embodiment of the present application turns off the sleep function when the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, thereby preventing all output terminals connected to the data lines of the display panel from remaining in a floating state, thereby avoiding worsening of the screen flickering problem caused by turning on the Wake function.

[0056] Furthermore, when the display signal is in a dynamic frequency switching state, a stable source driving voltage can be provided to the display panel in the V-Blank phase of each frame, thereby reducing screen flickering of the display panel and improving the display quality of the display panel during dynamic frequency switching. The stable source driving voltage can be a fixed output voltage such as a power supply voltage, which is provided to the data line of the display panel by the display driving circuit. For example, during dynamic frequency switching, the output end of the Source IC maintains a VDDA voltage output in the V-Blank phase, and the VDDA voltage represents an analog power supply voltage.

[0057] In an embodiment of the present application, the first interval duration is the latest interval duration between two adjacent switching frequencies of the display signal. When the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, the sleep function is turned off and a stable source drive voltage is provided to the display panel during the V-Blank phase of each frame. In this way, the screen flicker during dynamic frequency switching can be reduced and the Flicker level of the display panel during dynamic frequency switching can be improved.

[0058] Optionally, before step S1, the display driving method further includes:

[0059] Step S2, detecting the frequency corresponding to the current frame display signal;

[0060] Step S3, when the frequency of the current frame is different from the frequency of the previous frame, determining that the display signal switches the frequency once after the previous frame ends;

[0061] Step S4: determine the interval between the current switching frequency and the last switching frequency as the latest interval.

[0062] In some embodiments, the frequency of each frame of the display signal may be detected to determine whether the display signal switches frequency. Specifically, the frequency corresponding to the current frame display signal may be calculated based on the overall duration of the current frame display signal. Then, the frequency of the current frame is compared with the frequency of the previous frame. If the frequencies of the two frames of display signals are not equal, it means that the display signal switches frequency once after the previous frame ends.

[0063] In some embodiments, the duration of the V-Blank phase is related to the frequency of the display signal. The V-Blank phase of a high-frequency display signal is shorter and the V-Blank phase of a low-frequency signal is longer. Therefore, the duration of the V-Blank phase of each frame of the display signal can be detected to determine whether the display signal switches frequency. This is only an example, and the embodiments of the present application are not limited to this.

[0064] In some embodiments, the current switching frequency refers to a frequency switched after the previous frame ends. After the display signal switches frequency once from the previous frame to the current frame, the current switching frequency and the previous switching frequency can be used as two adjacent switching frequencies, and the interval between the current switching frequency and the previous switching frequency is the latest interval, that is, the first interval.

[0065] In some embodiments, since the frequency of the current frame needs to detect the total duration of the current frame or the duration of the V-Blank phase of the current frame first, the frequency of the current frame can be obtained at the end of the current frame or after the next frame starts. That is, if the display signal switches the frequency at the beginning of the current frame, the switching frequency will be detected at the end of the current frame or even after the next frame starts. The interval between the current switching frequency and the previous switching frequency does not include the total duration of the current frame, because the frequency of the display signal of the current frame is already the new frequency after the switch.

[0066] Optionally, step S4 may include the following sub-steps:

[0067] Sub-step A1: determine the total duration of all frames between the current switching frequency and the last switching frequency as the latest interval duration.

[0068] In some embodiments, when the display signal switches to a new frequency at the beginning of the next frame after a certain frame ends, the interval between two adjacent frequency switchings may be the total duration of all frames between the two adjacent frequency switchings. That is, when the display signal switches frequency once after the previous frame ends, all frames between the current switching frequency and the previous switching frequency are determined, and the total duration of all frames is determined as the latest interval duration.

[0069] For example, the current switching frequency is from 120Hz to 30Hz, and the last switching frequency was from 30Hz to 120Hz. The total duration of all frames between the current switching frequency and the last switching frequency is 4 frames, a total of 100ms. Then the latest interval between two adjacent switching frequencies is 100ms.

[0070] In some embodiments, if the display signal switching frequency is detected for the first time in the Nth frame, the timing is started from zero with the start time of the Nth frame as the origin, and when the display signal switching frequency is detected for the second time in the Mth frame, the timing duration is subtracted from the total duration of the Mth frame to obtain the interval duration between the two switching frequencies. Then the timing is reset to zero, and the timing is restarted from zero with the start time of the Mth frame as the origin, and so on, the latest interval duration between two adjacent switching frequencies can be obtained through timing. This is only an example, and the embodiments of the present application are not limited to this.

[0071] In the embodiment of the present application, by detecting the frequency corresponding to the display signal of the current frame, the latest frequency of the display signal can be obtained in real time. When the frequency of the current frame is different from the frequency of the previous frame, it is determined that the display signal switches the frequency once after the previous frame ends. In this way, the interval between the current switching frequency and the previous switching frequency is determined as the latest interval duration, that is, the first interval duration, and it is convenient to determine whether the display signal is dynamically switched according to the first interval duration, thereby adjusting the driving timing in time and improving the timeliness of the display driving method.

[0072] Optionally, after turning off the sleep function, step S1 further includes:

[0073] Sub-step B1, in the display phase of each frame, providing a data voltage corresponding to a display signal to the display panel to drive the display panel to display a picture.

[0074] In some embodiments, if the display signal switches frequency at the end of the Nth frame, it can be detected that the frequency of the N+1th frame is different from the frequency of the Nth frame at the end of the N+1th frame. If the first interval duration meets the dynamic frequency switching condition, the sleep function can be turned off at the N+2th frame, and the data voltage corresponding to the display signal is provided to the data line of the display panel in the display (Active) phase of each frame starting from the N+2th frame, and the stable source drive voltage is provided to the data line of the display panel in the V-Blank phase of each frame starting from the N+2th frame.

[0075] Among them, starting from the N+2th frame, each frame may include the N+2th frame, or may not include the N+2th frame, which depends on whether the display driving circuit can execute instructions in the N+2th frame to complete the operations of shutting down the sleep function and switching the output voltage. The embodiments of the present application do not limit this.

[0076] In the embodiment of the present application, after the sleep function is turned off during dynamic frequency switching, a data voltage corresponding to a display signal can be provided to the display panel in the Active phase of each frame to drive the display panel to display a picture, and a stable source drive voltage can be provided to the display panel in the V-Blank phase of each frame. In this way, the display panel can be driven normally to display a picture, and the screen flicker problem can be reduced in the V-Blank phase of each frame, thereby improving the picture quality of the display panel.

[0077] Optionally, the display driving method further includes:

[0078] Step S5, when the first interval duration meets the static frequency condition, turn on the sleep function, and provide the display panel with a data voltage corresponding to the display signal during the display phase of each frame, and keep the target output terminal in a suspended state during the vertical blanking phase of each frame; wherein the target output terminal is an output terminal connected to the data line of the display panel.

[0079] In some embodiments, the static frequency condition may be that the interval between the last two switching frequencies exceeds a preset duration threshold. If the first interval duration is greater than the preset duration threshold, the first interval duration meets the static frequency condition. In this embodiment, the Wake function can only be enabled when the latest interval duration between two adjacent switching frequencies, i.e., the first interval duration, meets the static frequency condition.

[0080] In some embodiments, if the display signal switches frequency at the end of the Nth frame, it can be detected at the end of the N+1 frame that the frequency of the N+1 frame is different from the frequency of the Nth frame. If the first interval duration meets the static frequency switching condition, the sleep function can be turned on in the N+2th frame, and in the display (Active) phase of each frame starting from the N+2th frame, the data voltage corresponding to the display signal is provided to the data line of the display panel, and, in the V-Blank phase of each frame starting from the N+2th frame, the output terminal connected to the data line of the display panel is kept in a suspended state.

[0081] The target output terminals may include all output terminals of the display driving circuit connected to the data lines of the display panel. For example, all output terminals of the Source IC are kept in a Floating state during the V-Blank phase of each frame.

[0082] In some embodiments, the Wake function can be turned on after the display driving circuit is powered on. When it is detected that the first interval duration meets the static frequency condition, if the Wake function has been turned on, it will continue to be turned on. If the Wake function has been turned off, the Wake function will be turned on again, and the data voltage corresponding to the display signal will be provided to the display panel during the Active phase of each frame, and the output end connected to the data line of the display panel will be kept in a Floating state during the V-Blank phase of each frame.

[0083] In the embodiment of the present application, when the first interval duration meets the static frequency condition, the sleep function is turned on, and the data voltage corresponding to the display signal is provided to the display panel in the display phase of each frame, and the output terminal connected to the data line of the display panel is kept in a suspended state in the vertical blanking phase of each frame. In this way, the logic power consumption in the V-Blank phase can be reduced in the static frequency scenario, thereby reducing the overall power consumption of the display device.

[0084] Optionally, the display driving method further includes:

[0085] Step S6, when the first interval duration is greater than the preset duration threshold, determining that the first interval duration meets the dynamic frequency switching condition;

[0086] Step S7: When the first interval duration is less than or equal to a preset duration threshold, it is determined that the first interval duration meets the static frequency condition.

[0087] In some embodiments, the preset duration threshold may be pre-stored in the display driver circuit, or the preset duration threshold may be set by a technician at the host end, and the host end sends the set preset duration threshold to the display driver circuit. For example, the technician sets the preset duration threshold to 150ms in the dynamic frequency switching software at the host end, and the host end sends 150ms to the display driver circuit.

[0088] In some embodiments, the first interval duration is compared with a preset duration threshold. If the first interval duration is greater than the preset duration threshold, it is determined that the first interval duration meets the dynamic frequency switching condition. If the first interval duration is less than or equal to the preset duration threshold, it is determined that the first interval duration meets the static frequency condition.

[0089] In the embodiment of the present application, the preset duration threshold can be flexibly set according to actual needs. By comparing the first interval duration with the preset duration threshold, it is convenient to determine whether the display signal is in a dynamic frequency switching state or a static frequency state, and then adopt the corresponding driving logic to make the application scenario more extensive.

[0090] Figure 2 1 is a schematic diagram of a structure of a display driving circuit 10 provided in an embodiment of the present application. The display driving circuit 10 comprises: a timing control circuit 101 and a source driving circuit 102;

[0091] The timing control circuit 101 is connected to the source driving circuit 102, and is configured to turn off the sleep function when the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, and send a first control signal to the source driving circuit 102 in the vertical blanking phase of each frame;

[0092] The source driving circuit 102 is configured to provide a stable source driving voltage to the display panel in response to a first control signal during a vertical blanking phase of each frame; wherein the first interval duration is the latest interval duration between two adjacent switching frequencies of the display signal.

[0093] In some embodiments, the timing control circuit 101 may be a timing controller (TCON), which may be connected to the host end of the display device to receive a display signal sent by the host end. The host end may be installed with dynamic frequency switching software, and a technician may set parameters in the dynamic frequency switching software. The host end may switch the frequency of the display signal, and the timing control circuit 101 may detect the frequency of the display signal after receiving the display signal.

[0094] In some embodiments, the source driver circuit 102 may be a source driver chip (Source IC), which may be connected to the timing control circuit 101 and the display panel respectively, receive a sleep control (Wake) signal sent by the timing control circuit 101, and provide a corresponding output voltage to the display panel in the V-Blank phase of each frame in response to the Wake signal.

[0095] In some embodiments, the timing control circuit 101 can be used as the execution subject of the display driving method in the above-mentioned embodiment. When the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, the timing control circuit 101 can turn off the sleep function and send a first control signal to the source driving circuit 102 in the V-Blank phase of each frame. The first control signal can be a sleep control signal with a first level, such as a high-level Wake signal.

[0096] In some embodiments, the source driving circuit 102 can provide a stable source driving voltage to the display panel in response to a sleep control signal having a first level during the V-Blank phase of each frame. For example, the output terminal of the Source IC maintains a VDDA voltage output during the V-Blank phase. In this way, the screen flicker of the display panel during the V-Blank phase can be reduced.

[0097] Optionally, the timing control circuit 101 is configured to detect the frequency corresponding to the current frame display signal. When the frequency of the current frame is different from the frequency of the previous frame, it is determined that the display signal switches frequency once after the end of the previous frame, and the interval duration between this switching frequency and the previous switching frequency is determined as the latest interval duration.

[0098] Optionally, the timing control circuit 101 is configured to determine the total duration of all frames between the current switching frequency and the last switching frequency as the latest interval duration.

[0099] Optionally, the timing control circuit 101 is configured to determine that the first interval duration meets the dynamic frequency switching condition when the first interval duration is greater than a preset duration threshold, and to determine that the first interval duration meets the static frequency condition when the first interval duration is less than or equal to the preset duration threshold.

[0100] In some embodiments, the code for detecting dynamic frequency cutting can be pre-written into the timing control circuit 101, or written into a storage circuit connected to the timing control circuit 101, and the code for detecting dynamic frequency cutting is used to execute the display driving method of the aforementioned embodiment, that is, to detect the display signal frequency, turn off the sleep function when the display signal is in a dynamic frequency cutting state, and turn on the sleep function in a static frequency state. For example, the code for detecting dynamic frequency cutting is pre-written into a flash memory chip (Flash IC) connected to TCON, and the code for detecting dynamic frequency cutting is read and executed from the Flash IC after TCON is powered on. This is only an example, and the embodiments of the present application are not limited to this.

[0101] In some embodiments, the timing control circuit 101 can detect the frequency of each frame of the display signal to determine whether the display signal switches frequency. Specifically, the timing control circuit 101 can calculate the frequency corresponding to the current frame display signal according to the overall duration of the current frame display signal, and then compare the frequency of the current frame with the frequency of the previous frame. If the frequencies of the two frames of display signals are not equal, it means that the display signal switches frequency once after the previous frame ends.

[0102] In some embodiments, the timing control circuit 101 can detect the duration of the V-Blank phase of each frame of the display signal to determine whether the display signal switches frequency. Specifically, the timing control circuit 101 compares the duration of the V-Blank phase of the current frame with the duration of the V-Blank phase of the previous frame. If the durations of the V-Blank phases corresponding to the two frames of display signals are different, it means that the frequencies of the two frames of display signals are different, that is, the display signal switches frequency once after the end of the previous frame.

[0103] In some embodiments, the timing control circuit 101 can determine the frequency of the current frame display signal based on the interval between the current switching frequency and the previous switching frequency at the end of the current frame or the beginning of the next frame, and then determine whether the frequency of the current frame is the same as the frequency of the previous frame. If the frequencies are not the same, the timing control circuit 101 determines that a switching frequency occurs after the end of the previous frame, and then the timing control circuit 101 can use the interval between the current switching frequency and the previous switching frequency as the latest interval duration, that is, the first interval duration. Among them, the first interval duration can be the total duration of all frames between the current switching frequency and the previous switching frequency.

[0104] In some embodiments, if the timing control circuit 101 detects the display signal switching frequency for the first time in the Nth frame, the timing is started from zero with the start time of the Nth frame as the origin, and when the display signal switching frequency is detected for the second time in the Mth frame, the timing duration is subtracted from the total duration of the Mth frame to obtain the interval duration between the two switching frequencies. Then the timing control circuit 101 resets the timing and starts timing from zero again with the start time of the Mth frame as the origin, and so on, the latest interval duration between two adjacent switching frequencies can be obtained by timing. This is only an example, and the embodiments of the present application are not limited to this.

[0105] In some embodiments, the preset time threshold can be pre-stored in the timing control circuit 101 or a storage circuit connected to the timing control circuit 101, or the preset time threshold can be set by a technician on the host side, and the host side sends the set preset time threshold to the timing control circuit 101.

[0106] In some embodiments, the timing control circuit 101 compares the first interval duration with a preset duration threshold. If the first interval duration is greater than the preset duration threshold, it is determined that the first interval duration meets the dynamic frequency switching condition. If the first interval duration is less than or equal to the preset duration threshold, it is determined that the first interval duration meets the static frequency condition.

[0107] Optionally, the timing control circuit 101 is configured to send a second control signal to the source driving circuit 102 during the display phase of each frame after turning off the sleep function;

[0108] The source driving circuit 102 is configured to provide a data voltage corresponding to a display signal to the display panel in response to a second control signal during a display phase of each frame, so as to drive the display panel to display a picture.

[0109] In some embodiments, the second control signal sent by the timing control circuit 101 to the source driving circuit 102 may be a sleep control signal with a first level, such as a high-level Wake signal. In the Active phase of each frame, the source driving circuit 102 responds to the sleep control signal with a first level and provides a data voltage corresponding to the display signal to the display panel to drive the display panel to display a picture.

[0110] In some embodiments, when the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, the timing control circuit 101 can turn off the sleep function and continue to send a sleep control signal with a first level to the source driver circuit 102. For example, TCON continuously maintains the Wake signal at a high level, and all output terminals of the Source IC maintain a VDDA voltage output in the V-Blank stage.

[0111] In some embodiments, if the host switches the frequency of the display signal at the end of the Nth frame, then at the end of the N+1th frame or even after the start of the N+2th frame, the timing control circuit 101 can detect that the frequency of the N+1th frame is different from the frequency of the Nth frame. The timing control circuit 101 can compare the first interval duration with the preset duration threshold. If the first interval duration meets the dynamic frequency switching condition, the timing control circuit 101 can turn off the sleep function at the N+2th frame, and continuously send a sleep control signal with a first level to the source driving circuit 102 starting from the N+2th frame, so that the source driving circuit 102 provides the data voltage corresponding to the display signal to the data line of the display panel in the Active phase of each frame, and provides a stable source driving voltage to the data line of the display panel in the V-Blank phase of each frame.

[0112] Among them, starting from the N+2th frame, each frame may include the N+2th frame, or may not include the N+2th frame, which depends on whether the source driving circuit 102 can receive and execute the instructions of the timing control circuit 101 within the N+2th frame to complete the operation of shutting down the sleep function and switching the output voltage. The embodiment of the present application does not impose any restrictions on this.

[0113] In this way, when the display signal is in a dynamic frequency switching state, the timing control circuit 101 turns off the sleep function and controls the source driving circuit 102 to provide a stable source driving circuit 102 to the display panel during the V-Blank phase of each frame, thereby reducing the screen flicker in the V-Blank phase and improving the image quality of the display panel.

[0114] Optionally, the timing control circuit 101 is configured to start the sleep function when the first interval duration meets the static frequency condition, and send a third control signal to the source driving circuit 102 in the display phase of each frame, and send a fourth control signal to the source driving circuit 102 in the vertical blanking phase of each frame;

[0115] The source driving circuit 102 is configured to respond to the third control signal during the display phase of each frame to provide a data voltage corresponding to the display signal to the display panel, and to respond to the fourth control signal during the vertical blanking phase of each frame to keep the output terminal connected to the data line of the display panel in a suspended state.

[0116] In some embodiments, the third control signal sent by the timing control circuit 101 to the source driving circuit 102 may be a sleep control signal with a first level, such as a high level Wake signal, and the fourth control signal may be a sleep control signal with a second level, such as a low level Wake signal.

[0117] In some embodiments, the source driver circuit 102 may provide a data voltage corresponding to a display signal to the display panel in response to a sleep control signal having a first level during the Active phase of each frame, so as to drive the display panel to display a picture. Also, the source driver circuit 102 may maintain an output terminal connected to a data line of the display panel in a Floating state in response to a sleep control signal having a second level during the V-Blank phase of each frame. In this way, the logic power consumption of the source driver circuit 102 during the V-Blank phase may be reduced.

[0118] In some embodiments, if the host switches the frequency of the display signal at the end of the Nth frame, then at the end of the N+1th frame or even after the start of the N+2th frame, the timing control circuit 101 can detect that the frequency of the N+1th frame is different from the frequency of the Nth frame. The timing control circuit 101 can compare the first interval duration with the preset duration threshold. If the first interval duration meets the static frequency switching condition, the sleep function can be turned on in the N+2th frame, and a sleep control signal with a first level is sent to the source driving circuit 102 in the Active phase of each frame starting from the N+2th frame, so that the source driving circuit 102 provides the data voltage corresponding to the display signal to the data line of the display panel. And, the timing control circuit 101 sends a sleep control signal with a second level to the source driving circuit 102 in the V-Blank phase of each frame starting from the N+2th frame, so that the source driving circuit 102 keeps the output terminal connected to the data line of the display panel in the Floating state.

[0119] In some embodiments, the Wake function can be turned on after the TCON is powered on. When the TCON detects that the first interval duration meets the static frequency condition, if the Wake function has been turned on, it will continue to be turned on. If the Wake function has been turned off, the TCON will re-enable the Wake function and send a high-level Wake signal to the Source IC during the Active phase of each frame, and send a low-level Wake signal to the Source IC during the V-Blank phase of each frame, so that all output terminals of the Source IC remain in a Floating state.

[0120] Figure 3 is a driving flow chart of a display driving method provided in an embodiment of the present application, such as Figure 3 As shown, TCON is powered on, TCON detects the switching frequency for the Nth time and the switching frequency for the N+1th time, and TCON confirms whether the first interval duration t between the two adjacent switching frequencies exceeds the preset duration threshold of 150ms. If t≤150ms, the first interval duration t meets the dynamic frequency switching condition, TCON turns off the Wake function, and sends a high-level Wake signal to the Source IC in the V-Blank stage of each frame, so that the Source IC maintains the VDDA voltage output in the V-Blank stage of each frame to provide a stable source drive voltage to the data line of the display panel, which can reduce the screen flicker of the display panel in the V-Blank stage.

[0121] like Figure 3As shown, if t>150ms, the first interval duration t meets the static frequency condition, TCON turns on the Wake function, and sends a low-level Wake signal to the Source IC in the V-Blank phase of each frame, so that the Source IC keeps the output terminal connected to the data line in the Floating state during the V-Blank phase of each frame, which can reduce the logic power consumption of the Source IC in the V-Blank phase.

[0122] like Figure 3 As shown in the figure, after each Wake function is turned on, TCON can confirm whether the system is powered off. If not, it returns to continue detecting whether the display signal is frequency-cut, otherwise it stops detecting. Similarly, after turning off the Wake function, TCON can confirm whether the system is powered off. If not, it returns to continue detecting whether the display signal is frequency-cut, otherwise it stops detecting.

[0123] Figure 4 is a timing diagram of a display driving method provided by an embodiment of the present application, such as Figure 4 As shown, TCON receives display signals. Each frame of display signals includes an Active phase and a V-Blank phase. TCON can detect whether the frequency of each frame of display signals is switched. Figure 4 As shown, before the display signal switches frequency for the Nth time, the total duration of M frames of 120Hz display signal is greater than 150ms, and after the Nth switching frequency, the total duration of 4 frames of 30Hz display signal is 133ms, and then, after the display signal switches frequency for the N+1th time, the total duration of 12 frames of 120Hz display signal is 100ms.

[0124] like Figure 4 As shown, for the Nth switching frequency of the display signal, TCON can detect that the display signal switches frequency once after the end of the first frame in the 4-frame 30Hz display signal. Similarly, for the N+1th switching frequency of the display signal, TCON can detect that the display signal switches frequency again after the end of the first frame in the 12-frame 120Hz display signal. Since the interval between the two adjacent switching frequencies is 133ms, 133ms is less than the preset duration threshold of 150ms. Therefore, TCON determines that 133ms meets the dynamic frequency switching condition and the sleep function needs to be turned off.

[0125] like Figure 4As shown, the STV signal is the frame start signal sent by TCON to the GOA circuit of the display panel. The frequency of the STV signal corresponds to the frequency of the display signal. The STV signal includes two states: high frequency 120Hz and low frequency 30Hz. The Wake_A signal is the sleep control signal sent by TCON to the Source IC. The Wake_A signal is valid at a low level. When the Wake function needs to be turned on, TCON sets the Wake_A signal low, and when the Wake function needs to be turned off, TCON sets the Wake_A signal high. The Sout_A signal is the output signal of the Source IC.

[0126] like Figure 4 As shown, when the display signal is in a static frequency state, TCON sends a high-level Wake_A signal to Source IC in the Active phase of each frame, so that Source IC provides the display panel with a data voltage corresponding to the display signal, and sends a low-level Wake_A signal to Source IC in the V-Blank phase of each frame, so that Source IC keeps all output terminals in a Floating state, thereby reducing the power consumption of Source IC in the V-Blank phase.

[0127] like Figure 4 As shown, when the display signal is in the dynamic frequency switching state, TCON continuously sends a high-level Wake_A signal to the Source IC in the Active phase and V-Blank phase of each frame, so that the Source IC provides the display panel with a data voltage corresponding to the display signal in the Active phase of each frame, so that all output terminals of the Source IC maintain the VDDA voltage output in the V-Blank phase of each frame, thereby reducing screen flickering during dynamic frequency switching.

[0128] In the related art, when the display signal is in the static frequency state and the dynamic frequency cutting state, TCON will turn on the Wake function, and set the Wake_B signal to a high level in the Active phase of each frame, and set the Wake_B signal to a low level in the V-Blank phase of each frame, so that all output ends of the Source IC in the V-Blank phase are in the Floating state, so as to reduce the power consumption of the Source IC in the V-Blank phase, such as Figure 5 The Wake_B and Sout_B signals of the Source IC are as follows. The Sout_B signal is the output signal of the Source IC.

[0129] A display driving circuit 10 provided in an embodiment of the present application can turn off the sleep function of the timing control circuit 101 when the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, thereby avoiding the deterioration of the screen flicker problem. The source driving circuit 102 provides a stable source driving voltage to the display panel, thereby reducing the screen flicker of the display panel, improving the Flicker level of the display panel, and improving the display quality of the display panel during dynamic frequency switching.

[0130] Figure 6 is one of the test waveform diagrams of a display driving circuit 10 provided in an embodiment of the present application, such as Figure 6 As shown, TCON receives a static 30Hz display signal, sends a high-level Wake signal to the Source IC in the Active phase of each frame, and sends a low-level Wake signal to the Source IC in the V-Blank phase of each frame. Figure 6 As shown in the Sout signal waveform, the Source IC responds to the high-level Wake signal in the Active phase of each frame and outputs the data voltage corresponding to the display signal, while the Source IC responds to the low-level Wake signal in the V-Blank phase of each frame, and all output terminals are in the Floating state to reduce the power consumption of the Source IC in the V-Blank phase.

[0131] Figure 7 This is a second test waveform diagram of a display driving circuit 10 provided in an embodiment of the present application. Figure 7 As shown, TCON receives a static 120Hz display signal, sends a high-level Wake signal to the Source IC in the Active phase of each frame, and sends a low-level Wake signal to the Source IC in the V-Blank phase of each frame. Figure 7 As shown in the Sout signal waveform, the Source IC responds to the high-level Wake signal in the Active phase of each frame and outputs the data voltage corresponding to the display signal, while the Source IC responds to the low-level Wake signal in the V-Blank phase of each frame, and all output terminals are in the Floating state to reduce the power consumption of the Source IC in the V-Blank phase. Figure 6 and Figure 7 It is also shown that TCON sends an STV signal to the GOA circuit of the display panel, and the frequency of the STV signal corresponds to the frequency of the display signal.

[0132] Figure 8This is the third test waveform diagram of a display driving circuit 10 provided in the embodiment of the present application. The technician can run the dynamic frequency cutting software on the host side, and set the dynamic frequency cutting software to cycle through 4 frames of 30Hz → 12 frames of 120Hz → 4 frames of 30Hz. Figure 8 As shown, TCON receives the display signal in the dynamic frequency switching state. TCON detects that the latest interval between two adjacent switching frequencies is 133ms or 100ms, which is less than the preset duration threshold of 150ms. Then TCON continues to send a high-level Wake signal to the Source IC, so that the Source IC responds to the high-level Wake signal in the Active phase of each frame and outputs the data voltage corresponding to the display signal. The Source IC responds to the high-level Wake signal in the V-Blank phase of each frame, and all output terminals maintain the L63 grayscale voltage output. At this time,

[0133] It should be noted that since the measurement point of the Sout signal is before the OP of the Source IC, the Sout signal waveform cannot maintain the voltage of VDDA in the V-Blank stage. The dynamic flicker value was tested under the L63 grayscale screen and improved by 11db. In this way, low power consumption is maintained in the static frequency state without increasing the BOM cost, and the flicker level is improved in the dynamic frequency cutting state.

[0134] An embodiment of the present application provides a display device, which includes a display panel and a display driving circuit 10 as described in the above embodiment; a source driving circuit 102 in the display driving circuit 10 is connected to the display panel.

[0135] A display device provided in an embodiment of the present application can achieve the same or similar technical effects as the display driving method in the aforementioned embodiment, and will not be described again here to avoid repetition.

[0136] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0137] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0138] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0139] Finally, it should be noted that, in this article, relational terms such as first and second, etc. 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 terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0140] The display driving method, display driving circuit and display device provided by the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A display driving method, characterized in that: The display driving method comprises: When the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, the sleep function is turned off, and a stable source driving voltage is provided to the display panel during the vertical blanking phase of each frame; The first interval duration is the latest interval duration between two consecutive switching frequencies of the display signal.

2. The display driving method according to claim 1, characterized in that: Before shutting down the sleep function, the display driving method further includes: Detecting the frequency corresponding to the display signal of the current frame; When the frequency of the current frame is different from the frequency of the previous frame, determining that the display signal switches the frequency once after the previous frame ends; The interval duration between the current switching frequency and the last switching frequency is determined as the latest interval duration.

3. The display driving method according to claim 2, characterized in that: The step of determining the interval duration between the current switching frequency and the last switching frequency as the latest interval duration includes: The total duration of all frames between the current switching frequency and the last switching frequency is determined as the latest interval duration.

4. The display driving method according to claim 1, characterized in that: After the sleep function is turned off, the display driving method further includes: In the display phase of each frame, a data voltage corresponding to the display signal is provided to the display panel to drive the display panel to display a picture.

5. The display driving method according to any one of claims 1 to 4, characterized in that: The display driving method further includes: When the first interval duration meets the static frequency condition, the sleep function is turned on, and the data voltage corresponding to the display signal is provided to the display panel during the display phase of each frame, and the target output terminal is kept in a suspended state during the vertical blanking phase of each frame; wherein the target output terminal is an output terminal connected to the data line of the display panel.

6. The display driving method according to claim 1, characterized in that: The display driving method further includes: When the first interval duration is greater than a preset duration threshold, determining that the first interval duration meets the dynamic frequency switching condition; When the first interval duration is less than or equal to the preset duration threshold, it is determined that the first interval duration meets the static frequency condition.

7. A display driving circuit, characterized in that: The display driving circuit comprises: a timing control circuit and a source driving circuit; The timing control circuit is connected to the source driving circuit and is configured to turn off the sleep function when the first interval duration corresponding to the display signal meets the dynamic frequency switching condition, and send a first control signal to the source driving circuit in the vertical blanking phase of each frame; The source driving circuit is configured to provide a stable source driving voltage to the display panel in response to the first control signal during the vertical blanking phase of each frame; wherein the first interval duration is the latest interval duration between two adjacent switching frequencies of the display signal.

8. The display driving circuit according to claim 7, characterized in that: The timing control circuit is configured to send a second control signal to the source driving circuit in the display phase of each frame after turning off the sleep function; The source driving circuit is configured to provide the display panel with a data voltage corresponding to the display signal in response to the second control signal during the display phase of each frame, so as to drive the display panel to display a picture.

9. The display driving circuit according to claim 7, characterized in that: The timing control circuit is configured to start the sleep function when the first interval duration meets the static frequency condition, and send a third control signal to the source driving circuit in the display phase of each frame, and send a fourth control signal to the source driving circuit in the vertical blanking phase of each frame; The source driving circuit is configured to respond to the third control signal during the display phase of each frame to provide the display panel with a data voltage corresponding to the display signal, and to respond to the fourth control signal during the vertical blanking phase of each frame to keep the output terminal connected to the data line of the display panel in a suspended state.

10. The display driving circuit according to claim 7, characterized in that: The timing control circuit is configured to detect the frequency corresponding to the display signal of the current frame. When the frequency of the current frame is different from the frequency of the previous frame, it is determined that the display signal switches its frequency once after the end of the previous frame, and the interval duration between this switching frequency and the previous switching frequency is determined as the latest interval duration.

11. The display driving circuit according to claim 10, characterized in that: The timing control circuit is configured to determine the total duration of all frames between the current switching frequency and the last switching frequency as the latest interval duration.

12. The display driving circuit according to claim 7, characterized in that: The timing control circuit is configured to determine that the first interval duration meets the dynamic frequency switching condition when the first interval duration is greater than a preset duration threshold, and to determine that the first interval duration meets the static frequency condition when the first interval duration is less than or equal to the preset duration threshold.

13. A display device, characterized in that: The display device comprises a display panel and a display driving circuit as claimed in any one of claims 7 to 12; The source driving circuit in the display driving circuit is connected to the display panel.

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