Electronic device and driving method therefor, display driver, and processor

Abstract

Embodiments of this application provide an electronic device and a driving method therefor, a display drive, and a processor, which relate to the field of electronic technologies, to cause an actual screen refresh frequency to respond to an image refresh frequency of a core processing chip like an upper-layer SOC in a timely manner. The electronic device includes a DDIC and an SOC. The DDIC is configured to send a TE signal, where a frequency of the TE signal is a first fixed frequency f1, and f1 is a common multiple of a plurality of screen refresh frequencies f supported by the electronic device. For example, if f supported by the electronic device includes 60 Hz, 90 Hz, and 120 Hz, f1 is 360 Hz. The SOC is configured to receive the TE signal, and output display data to the DDIC at a variable frequency f2, where f1=n×f2. In this case, a pulse period of f1 is a first pulse period T1, a pulse period of f2 is a second pulse period T2, and T2=n×T1. n is a ratio of f1 to f of a current frame. The second pulse period T2 of f2 of the current frame is always n times the first pulse period T1 of f1. To be specific, the display data is always sent once after n pieces of T1. n varies with f.

Description

[0001] This application claims priority to Chinese Patent Application No. 202310878046.2, filed with the China National Intellectual Property Administration on July 17, 2023 and entitled "ELECTRONIC DEVICE AND DRIVING METHOD THEREFOR, DISPLAY DRIVE, AND PROCESSOR", which is incorporated herein by reference in its entirety.TECHNICAL FIELD

[0002] This application relates to the field of electronic technologies, and in particular, to an electronic device and a driving method therefor, a display drive, and a processor.BACKGROUND

[0003] With development of display technologies, an electronic device with a high frame frequency gradually becomes a market development trend. The electronic device with a high frame frequency usually has a function of switching between different screen refresh frequencies based on different use scenarios. For example, a screen refresh frequency may switch between 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, and 120 Hz.

[0004] Currently, display data may be transmitted to a displaying of an electronic device mainly in the following two modes: a video mode (video mode) and a command mode (command mode, CMD). In the command mode, a tearing effect (tear effect, TE) signal that changes with a screen refresh frequency is needed, so that a frequency at which a processor sends display data is consistent with a frequency at which a display drive of the electronic device needs to receive display data, to cause an actual screen refresh frequency to respond to an image refresh frequency (namely, a theoretical screen refresh frequency) of the processor in a timely manner.

[0005] However, how to enable the actual screen refresh frequency to respond to the image refresh frequency of the processor in a timely manner is a technical problem that urgently needs to be resolved by a person skilled in the art at present.SUMMARY

[0006] Embodiments of this application provide an electronic device and a driving method therefor, a display drive, and a processor, to cause an actual screen refresh frequency to respond to an image refresh frequency (namely, a theoretical screen refresh frequency) of a processor in a timely manner.

[0007] To achieve the foregoing objective, the following technical solutions are used in this application.

[0008] According to a first aspect of embodiments of this application, an electronic device is provided. The electronic device includes a display drive and a processor. The display drive may be, for example, a DDIC. The display drive is configured to send a TE signal. A frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of a plurality of screen refresh frequencies supported by the electronic device. For example, if the screen refresh frequencies supported by the electronic device include 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, and 120 Hz, the first fixed frequency is 360 Hz. The processor is configured to receive the TE signal, and output display data to the display drive at a variable frequency. f1=n×f2, where f1 is the first fixed frequency, and f2 is a variable frequency of a current frame. To be specific, a pulse period of the first fixed frequency f1 is a first pulse period T1, and a pulse period of the variable frequency f2 is a second pulse period T2, and T2=n×T1. n is a ratio of the first fixed frequency to a screen refresh frequency of the current frame. The second pulse period T2 of the current frame is always n times the first pulse period T1. To be specific, the display data is always sent once after n pieces of T1. n varies with the screen refresh frequency, and n is a positive integer.

[0009] In the electronic device provided in this embodiment of this application, the frequency of the TE signal sent by the display drive is the first fixed frequency f1 that is a high frequency, and the first fixed frequency f1 is a common multiple of all screen refresh frequencies f that can be supported by the electronic device. In this case, the first fixed frequency f1 can be exactly divided by each screen refresh frequency f, that is, f1 / f=n. The first fixed frequency f1 can also be exactly divided by each variable frequency f2. That is, f1 / f2=n. Correspondingly, the second pulse period T2 of the variable frequency f2 can be exactly divided by the first pulse period T1 of the first fixed frequency f1. That is, T2 / T1=n. To be specific, each second pulse period T2 is n times the first pulse period T1. After the screen refresh frequency f (namely, a theoretical screen refresh frequency) of the current frame changes, the variable frequency f2 only needs to synchronously change based on a quantity n of first pulse periods T1 that are intervals, without delaying by one frame based on a screen refresh frequency f corresponding to a previous frame. Therefore, the variable frequency f2 can respond to the change in the screen refresh frequency f in a timely manner, to quickly follow the change in the screen refresh frequency f, and change a value of the variable frequency f2 to the screen refresh frequency f. In this case, an actual screen refresh frequency of the electronic device is also the screen refresh frequency f. In view of this, in this embodiment of this application, when the screen refresh frequency f of the electronic device changes, the actual screen refresh frequency can respond to an image refresh frequency (namely, the theoretical screen refresh frequency) of the processor in a timely manner, to implement smooth stepless switching between a plurality of screen refresh frequencies f. In addition, because smooth stepless switching can be performed in various scenarios, only one set of frame switching drive logic needs to be used, without a need to be compatible with a case in which a change in a transmit frequency of the processor is delayed and a case in which a change in a transmit frequency of the processor is not delayed. This reduces complexity of logic processing, enables a screen to change with an image, and implements stepless frame switching, and can further avoid a logic error caused by inconsistent driver interaction timing.

[0010] In a possible implementation, the display drive is configured to continuously send the TE signal, and the processor is configured to output the display data to the display drive once after cumulatively receiving n pulses of the TE signal.

[0011] To be specific, logic of interaction between the display drive and the processor is as follows: The display drive continuously sends the TE signal at the first fixed frequency, and the processor internally counts n pulses of the TE signal as a condition for triggering the processor to send the display data. A change in a refresh frequency is implemented between the display drive and the processor directly through internal counting by the processor, and the change in the refresh frequency does not need to be implemented by using a CMD. Logic of sending the TE signal is simple, and control difficulty is reduced.

[0012] In a possible implementation, the display drive is configured to skip sending the TE signal in n2 pulse periods after sending n1 pulses of the TE signal, where a display internally refreshes data received by the display drive to the display within time of n1 pulses. In this process, if an SOC re-sends data, a data conflict occurs, leading to abnormal display like erratic display. The processor is configured to output the display data to the display drive once after cumulatively receiving n1 pulses of the TE signal. n1+n2=n, where n2 is a fixed positive integer and is less than a minimum value of n.

[0013] To be specific, the display drive intermittently sends the TE signal; and after the processor is triggered to send the display data, the display drive no longer sends the TE signal to the processor, and the processor also suspends counting, and restarts counting after receiving the TE signal next time. This can avoid secondary data transmission between the SOC and the DDIC when the display drive transmits the display data to the display, and can reduce a probability that a frequency (the variable frequency) at which the processor sends the display data conflicts with the screen refresh frequency of the current frame due to a counting error. This can reduce a requirement on stability of a processor system, and eliminate abnormal display caused by a conflict between the variable frequency and the screen refresh frequency of the current frame that occurs due to an occasional stability issue.

[0014] In a possible implementation, the first fixed frequency is a lowest common multiple of the plurality of screen refresh frequencies supported by the electronic device. The first fixed frequency is the lowest common multiple of the plurality of screen refresh frequencies, and a requirement of the electronic device may be met by using a minimum first fixed frequency, to reduce power consumption of the electronic device.

[0015] In a possible implementation, the screen refresh frequency of the current frame is switchable without a rule. The electronic device provided in this application is applicable to various application scenarios.

[0016] In a possible implementation, the electronic device further includes the display; and the display drive is further configured to send a light-emitting control start STV-EM signal to the display, where a frequency of the STV-EM signal is a second fixed frequency, and the second fixed frequency is an integer multiple of the first fixed frequency.

[0017] The second fixed frequency of the STV-EM signal is set to be an integer multiple of the first fixed frequency of the TE signal, so that the first pulse period of the TE signal is an integer multiple of a pulse period of the STV-EM signal. In this case, a quantity of pulses of the STV-EM signal that correspond to each pulse period of the TE signal is fixed, to avoid a case that pulse periods correspond to different quantities of pulses of the STV-EM signal. Therefore, a pulse period of the TE signal may be considered as a minimum repetition unit with fixed luminance. During switching of the screen refresh frequency, luminance of the display may be kept consistent to improve display effect.

[0018] According to a second aspect of embodiments of this application, a driving method for an electronic device is provided. The electronic device includes a display drive and a processor. The driving method includes: The display drive sends a tearing effect TE signal, where a frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of a plurality of screen refresh frequencies supported by the electronic device. The processor receives the TE signal, and outputs display data to the display drive at a variable frequency. f1=n×f2, where f1 is the first fixed frequency, f2 is a variable frequency of a current frame, n is a ratio of the first fixed frequency to a screen refresh frequency of the current frame, and n varies with the screen refresh frequency. In the driving method provided in the second aspect of this application, a screen can change with an image, and stepless frame switching can be implemented. A screen refresh rate can follow an image processing frequency (namely, a theoretical screen refresh frequency) of the processor in real time, without additional interaction through an instruction for changing the screen refresh rate. Overall driving logic is simple and efficient.

[0019] In a possible implementation, the display drive continuously sends the TE signal, and the processor outputs the display data to the display drive once after cumulatively receiving n pulses of the TE signal.

[0020] In a possible implementation, the display drive skips sending the TE signal in n2 pulse periods after sending n1 pulses of the TE signal, and the processor outputs the display data to the display drive once after cumulatively receiving n1 pulses of the TE signal. n1+n2=n, where n2 is a fixed positive integer and is less than a minimum value of n.

[0021] In a possible implementation, the screen refresh frequency of the current frame is switchable without a rule.

[0022] In a possible implementation, the electronic device further includes a display, and the driving method includes: The display drive sends a light-emitting control start STV-EM signal to the display, where a frequency of the STV-EM signal is a second fixed frequency, and the second fixed frequency is an integer multiple of the first fixed frequency.

[0023] According to a third aspect of embodiments of this application, a display drive is provided, and is used in an electronic device. The display drive is configured to send a tearing effect TE signal, where a frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of a plurality of screen refresh frequencies supported by the electronic device. The display drive is further configured to receive display data at a variable frequency. f1=n×f2, where f1 is the first fixed frequency, f2 is a variable frequency of a current frame, n is a ratio of the first fixed frequency to a screen refresh frequency of the current frame, and n varies with the screen refresh frequency. After the display drive provided in the third aspect of this application is used in the electronic device provided in the first aspect, effects of the electronic device provided in the first aspect can be achieved. Details are not described herein again.

[0024] In a possible implementation, the display drive is configured to continuously send the TE signal.

[0025] In a possible implementation, the display drive is configured to skip sending the TE signal in n2 pulse periods after sending n1 pulses of the TE signal, where n2 is a fixed integer, and n1 varies with the screen refresh frequency.

[0026] In a possible implementation, the first fixed frequency is a lowest common multiple of the plurality of screen refresh frequencies supported by the electronic device.

[0027] In a possible implementation, the display drive is further configured to send a light-emitting control start STV-EM signal, where a frequency of the STV-EM signal is a second fixed frequency, and the second fixed frequency is an integer multiple of the first fixed frequency.

[0028] According to a fourth aspect of embodiments of this application, a processor is provided, and is used in an electronic device. The processor is configured to receive a tearing effect TE signal, where a frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of a plurality of screen refresh frequencies supported by the electronic device. The processor is further configured to output display data at a variable frequency. f1=n×f2, where f1 is the first fixed frequency, f2 is a variable frequency of a current frame, n is a ratio of the first fixed frequency to a screen refresh frequency of the current frame, and n varies with the screen refresh frequency. After the processor provided in the fourth aspect of this application is used in the electronic device provided in the first aspect, effects of the electronic device provided in the first aspect can be achieved. Details are not described herein again.

[0029] In a possible implementation, the processor is configured to output the display data once after cumulatively receiving n pulses of the TE signal.

[0030] In a possible implementation, the processor is configured to output the display data once after cumulatively receiving n1 pulses of the TE signal, where n-n1 is a fixed positive integer.

[0031] In a possible implementation, the first fixed frequency is a lowest common multiple of the plurality of screen refresh frequencies supported by the electronic device.

[0032] According to a fifth aspect of embodiments of this application, a computer-readable medium is provided. The computer-readable medium stores a computer program. When the computer program is run on an electronic device, the electronic device is enabled to perform the driving method according to any one of the implementations of the second aspect.BRIEF DESCRIPTION OF DRAWINGS

[0033] FIG. 1 is a diagram of an architecture of an electronic device according to an embodiment of this application; FIG. 2 is a diagram of a topology structure of a subpixel according to an embodiment of this application; FIG. 3 is a diagram of an architecture of an electronic device according to an embodiment of this application; FIG. 4A to FIG. 4E are diagrams of waveforms of a TE signal according to an embodiment of this application; FIG. 5 is a diagram of pulses of transmit frequencies of a TE signal and display data according to an embodiment of this application; FIG. 6 is another diagram of pulses of transmit frequencies of a TE signal and display data according to an embodiment of this application; FIG. 7 is a flowchart of a driving method for an electronic device according to an embodiment of this application; FIG. 8 is a diagram of waveforms of a TE signal and an STV-EM signal according to an embodiment of this application; FIG. 9 is still another diagram of pulses of transmit frequencies of a TE signal and display data according to an embodiment of this application; FIG. 10 is still another diagram of pulses of transmit frequencies of a TE signal and display data according to an embodiment of this application; FIG. 11 is a flowchart of a driving method for an electronic device according to an embodiment of this application; and FIG. 12 is another diagram of waveforms of a TE signal and an STV-EM signal according to an embodiment of this application. DESCRIPTION OF EMBODIMENTS

[0034] The following describes the technical solutions in embodiments of this application with reference to the accompanying drawings in embodiments of this application. Clearly, the described embodiments are merely some but not all of embodiments of this application.

[0035] The terms "second", "first", and the like below are merely intended for ease of description, and shall not be understood as an indication or implication of relative importance or an implicit indication of a quantity of indicated technical features. Therefore, a feature limited by "second", "first", or the like may explicitly or implicitly include one or more features. In descriptions of this application, "a plurality of" means two or more, unless otherwise specified.

[0036] In addition, in embodiments of this application, orientation terms such as "upper", "lower", "left", and "right" may include but are not limited to being defined relative to placement orientations of components shown in the accompanying drawings. It should be understood that these directional terms may be relative concepts and are used for relative description and clarification, and may vary correspondingly based on changes in the placement orientations of the components in the accompanying drawings.

[0037] In embodiments of this application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, the "connection" may be a fixed connection, a detachable connection, or an integrated connection, or may be a direct connection or an indirect connection implemented through an intermediate medium. In addition, the term "coupling" may be a direct electrical connection, or may be an indirect electrical connection through an intermediate medium. The term "contact" may be direct contact, or may be indirect contact through an intermediate medium.

[0038] In embodiments of this application, "and / or" describes an association relationship between associated objects, and indicates that three relationships may exist. For example, A and / or B may indicate the following cases: Only A exists, both A and B exist, and only B exists, where A and B may be in a singular form or a plural form. The character " / " usually indicates an "or" relationship between the associated objects.

[0039] An embodiment of this application provides an electronic device. The electronic device is, for example, a consumer electronic product, a home electronic product, a vehicle-mounted electronic product, or a financial terminal product that has a display function. The consumer electronic product is, for example, a mobile phone (mobile phone), a tablet computer (pad), a notebook computer, an e-reader, a personal computer (personal computer, PC), a personal digital assistant (personal digital assistant, PDA), a desktop display, an intelligent wearable product (for example, a smartwatch or a smart band), a virtual reality (virtual reality, VR) electronic device, an augmented reality (augmented reality, AR) electronic device, or an uncrewed aerial vehicle. The home electronic product is, for example, a smart door lock, a television, a remote control, a refrigerator, or a small charging home appliance (for example, a soy milk maker or a robot vacuum). The vehicle-mounted electronic product is, for example, a vehicle-mounted navigator or a vehicle-mounted high-density digital video disc (digital video disc, DVD). The financial terminal product is, for example, an automated teller machine (automated teller machine, ATM) or a terminal for self-help service handling. A specific form of the electronic device is not particularly limited in embodiments of this application.

[0040] FIG. 1 is a diagram of an architecture of an electronic device according to an embodiment of this application.

[0041] For example, the electronic device is a mobile phone. As shown in FIG. 1, the electronic device 1 includes a display 10, a display drive 20, and a processor 30. In FIG. 1, an example in which the electronic device 1 is a bar-type mobile phone is used for illustration. The electronic device 1 may alternatively be a foldable-screen mobile phone. This embodiment of this application provides only an example.

[0042] In some embodiments, the display 10 may be an organic light-emitting diode (organic light-emitting diode, OLED) display, and the OLED display can implement self-illumination. Alternatively, in some other embodiments, the display 10 may be a liquid crystal display (liquid crystal display, LCD). In this case, the electronic device further includes a backlight module configured to provide a light source for the display 10.

[0043] For any one of the foregoing types of displays 10, the display 10 includes an active display area (active area, AA) 101 and a non-display area 102 around the active display area 101. The active display area 101 is configured to display an image, and the active display area 101 includes a plurality of subpixels (subpixel) 11.

[0044] For ease of description, in this application, an example in which the plurality of subpixels 11 are arranged in a form of a matrix is used for description. Subpixels 11 arranged in a line along a horizontal direction X are referred to as subpixels in a same row, and subpixels 11 arranged in a line along a vertical direction Y are referred to as subpixels in a same column.

[0045] FIG. 2 is a diagram of a topology structure of a subpixel according to an embodiment of this application.

[0046] A pixel circuit 111 configured to control displaying of the subpixel 11 is disposed in the subpixel 11. When the display 10 is an OLED display, as shown in FIG. 2, the subpixel 11 further includes a light-emitting component L coupled to the pixel circuit 111. For example, the light-emitting component L is an OLED, an anode (anode, a) of the light-emitting component L is coupled to the pixel circuit 111, and a cathode (cathode, c) of the light-emitting component L is coupled to a voltage end VSS. The pixel circuit 111 is configured to drive the light-emitting component L to emit light.

[0047] The pixel circuit 111 includes a plurality of switch transistors (for example, a transistor M1 and a transistor M2 shown in FIG. 2), a drive transistor (for example, a transistor Td shown in FIG. 2), and a capacitor Cst.

[0048] For example, in FIG. 2, when the transistor M1 is turned on under the control of a scan (SCAN) signal, a data voltage Vdata may be written to the drive transistor Td, so that the drive transistor Td generates a drive current I corresponding to the data voltage Vdata.

[0049] When the light-emitting component L is an OLED, the light-emitting component L is a current light-emitting component. Therefore, a magnitude of the drive current I may be controlled by controlling a magnitude of the data voltage Vdata. In this way, after the drive current I flows through the light-emitting component L, light-emitting luminance of the light-emitting component L can be controlled.

[0050] After the drive transistor Td is turned on, the transistor M2 may control, under the control of a light-emitting control (EM) signal, an on / off status of a current path formed between a voltage end VDD and the voltage end VSS, to determine whether the drive current I can flow to the light-emitting component L.

[0051] A duty ratio (duty ratio) of the EM signal may be controlled through pulse width modulation (pulse width modulation). In this way, effective on duration, in each frame, of the current path formed between the voltage end VDD and the voltage end VSS, that is, effective duration in which the drive current I flows through the light-emitting component L, is controlled, to control the light-emitting luminance of the light-emitting component L.

[0052] In some embodiments, the display 10 further includes a gate drive circuit 12. The gate drive circuit 12 is configured to provide the SCAN signal and the EM signal for the pixel circuit 111. For example, the gate drive circuit 12 includes a gate scan module and a light-emitting control module. The gate scan module is configured to receive a gate scan start STV-SCAN signal provided by the display drive 20, and provide a SCAN signal for each row of pixel circuit 111 stage by stage. The light-emitting control module receives a light-emitting control start STV-EM signal provided by the display drive 20, and provides an EM signal for each row of pixel circuit 111 stage by stage. The gate drive circuit 12 may be integrated into the non-display area 102 of the display 10 by using a gate driver on array (gate driver on array, GOA) technology.

[0053] Still refer to FIG. 1. In some embodiments, the display drive 20 in the electronic device 1 may be a display driver integrated circuit (display driver IC, DDIC). In this case, the display drive 20 may be bonded (bonding) to the display 10 through a solder pad disposed in the non-display area 102 of the display 10.

[0054] In some embodiments, the processor 30 in the electronic device 1 may include an integrated circuit, a system-on-a-chip (system-on-a-chip, SOC), a microprocessor, or the like.

[0055] The display drive 20 may be coupled to the SOC through a mobile industry processor interface (mobile industry processor interface, MIPI). Certainly, the display drive 20 may alternatively be coupled to the SOC through another serializer / deserializer (serializer / deserializer, SerDes) high-speed interface.

[0056] For ease of description, an example in which the display drive 20 is a DDIC and the DDIC is coupled to the SOC through an MIPI interface is used below for description.

[0057] FIG. 3 is a diagram of an architecture of an electronic device according to an embodiment of this application.

[0058] In some embodiments, as shown in FIG. 3, a DDIC includes a timing control unit (timing controller, TCON) 21, a processing unit 22, a transceiver unit 23, and a frame buffer (frame buffer) unit 24. The frame buffer unit 24 is coupled to the transceiver unit 23 and the processing unit 22.

[0059] The TCON 21 is configured to send a tearing effect (tearing effect, TE) signal, where the TE signal is a square wave signal, and a high level of the TE signal is a useful signal of the TE signal.

[0060] In some embodiments, an SOC includes a graphics processing unit (graphics processing unit, GPU) 31, a display engine (display engine) unit 32, and a storage unit 33. The storage unit 33 is coupled to the GPU 31 and the display engine unit 32. For example, the storage unit 33 may be a double data rate synchronous dynamic random access memory (double data rate synchronous dynamic random access memory, DDR SDRAM) or a system memory (SRAM).

[0061] The GPU 31 may generate display data of an N th< frame (for example, a 1 st< frame) through data rendering (rendering) and programming (programming). The GPU 31 is coupled to the storage unit 33, and the display data generated by the GPU 31 is stored in the storage unit 33. For example, the display data of the 1 st< frame that is generated by the GPU 31 is stored in the storage unit 33.

[0062] The display engine unit 32 is coupled to the storage unit 33, and the display engine unit 32 may be further coupled to the TCON 21 in the DDIC through an MIPI interface. The display engine unit 32 is configured to receive the TE signal sent by the TCON 21, and extract the stored display data of the N th< frame (for example, the display data of the 1 st< frame) from the storage unit 33 based on the TE signal.

[0063] The display engine unit 32 is coupled to the DDIC through the MIPI interface, and the display engine unit 32 sends the display data of the N th< frame to the DDIC through the MIPI interface.

[0064] The transceiver unit 23 in the DDIC is coupled to the MIPI interface, and the transceiver unit 23 receives, through the MIPI interface, the display data of the N th< frame (for example, the 1 st< frame) that is sent by the display engine unit 32. The transceiver unit 23 is further coupled to the frame buffer unit 24, and the transceiver unit 23 buffers the display data of the N th< frame (for example, the 1 st< frame) in the frame buffer unit 24.

[0065] The processing unit 22 may extract the display data of the N th< frame (for example, the 1 st< frame) from the frame buffer unit 24, and generate, based on the display data of the N th< frame (for example, the 1 st< frame), a data voltage Vdata for controlling displaying of each subpixel 11.

[0066] A gate drive circuit 12 receives a horizontal synchronization signal (H-Sync). The gate drive circuit 12 scans subpixels 11 row by row (along an X direction) by starting from subpixels 11 in a 1 st< row, to turn on a part of transistors (for example, the transistor M1 in FIG. 2) in a pixel circuit 111 of each subpixel 11.

[0067] After sending the TE signal, the TCON 21 in the DDIC receives a vertical synchronization signal (V-Sync) that is input from the outside. After subpixels 11 in a row are scanned, the data voltage Vdata that is generated by the DDIC and that is used to control displaying of each subpixel 11 is transmitted to a pixel circuit 111 of each subpixel 11 in the row through a data line (data line, DL). The data voltage Vdata is written to a drive transistor Td through the transistor M1 that is turned on. In this way, the drive transistor Td in the pixel circuit 111 can generate a drive current I that is used to drive a light-emitting component L to emit light.

[0068] The gate drive circuit 12 may provide an EM signal for a gate of a part of transistors (for example, the transistor M2 in FIG. 2) in the pixel circuit 111 of the subpixel 11 row by row. When the EM signal is at a high level (for example, the high level is a useful signal), the current path formed between the voltage end VDD and the voltage end VSS in FIG. 2 is turned on, to control the light-emitting component L to emit light.

[0069] The DDIC obtains, through the MIPI interface, display data sent by the SOC, to generate the data voltage Vdata. A display 10 is controlled, based on the data voltage Vdata and a duty ratio of the EM signal, to display an N th< frame (for example, a 1 st< frame) of image.

[0070] After the transceiver unit 23 in the DDIC receives the display data of the N th< frame, the DDIC performs the foregoing display processing. At the same time, the GPU 31 in the SOC continues to generate display data of an (N+1) th< frame (for example, a 2 nd< frame), to cyclically perform the foregoing process.

[0071] To sum up, the GPU 31 first generates the display data of the N th< frame. When generating the display data of the (N+1) th< frame, the GPU 31 stores the display data of the N th< frame in the storage unit 33. The display engine unit 32 extracts the display data of the N th< frame from the storage unit 33 under the control of the TE signal sent by the DDIC, and sends the display data of the N th< frame to the transceiver unit 23 in the DDIC through the MIPI interface. The transceiver unit 23 may buffer the display data of the N th< frame in the frame buffer unit 24. The processing unit 22 extracts the display data of the N th< frame from the frame buffer unit 24, and drives the display 10 to display the N th< frame of image.

[0072] It can be learned from the foregoing descriptions that whether the SOC is to send display data to the DDIC is controlled by the TE signal sent by the DDIC, so that a frequency at which the SOC sends display data is consistent with a frequency at which the DDIC needs to receive display data, and an actual screen refresh frequency of the electronic device 1 can respond to an image refresh frequency (namely, a theoretical screen refresh frequency) of a processor in a timely manner.

[0073] FIG. 4A to FIG. 4E are diagrams of waveforms of a TE signal according to an embodiment of this application.

[0074] In some embodiments, a command mode (command mode, CMD) driving solution is used to align signal transmission between an SOC and a DDIC. For example, a frequency of a TE signal sent by the DDIC changes with a theoretical screen refresh frequency of a display 10. Alternatively, this is understood as that the frequency of the TE signal sent by the DDIC is the same as the screen refresh frequency. An instruction for changing the screen refresh frequency is delivered in advance, to enable the frequency of the TE signal to change correspondingly, so that the frequency of the TE signal changes with the theoretical screen refresh frequency.

[0075] As shown in FIG. 4A to FIG. 4C, the screen refresh frequency of the display 10 is 60 Hz, 90 Hz, and 120 Hz respectively, and the frequency of the TE signal sent by the DDIC is also 60 Hz, 90 Hz, and 120 Hz respectively. If the screen refresh frequency remains unchanged in an N th< frame to an (N+1) th< frame, the TE signal sent by the DDIC changes with the theoretical screen refresh frequency of the display 10 and does not affect displaying of the display 10.

[0076] In some embodiments, the screen refresh frequency varies in the N th< frame to the (N+1) th< frame. As shown in FIG. 4D, at a 1 st< pulse A1 and a 2 nd< pulse A2 of the TE signal, the screen refresh frequency is 90 Hz, and the frequency of the TE signal is also 90 Hz. In addition, at a moment of the 2 nd< pulse A2 (a moment indicated by an arrow in FIG. 4D), the screen refresh frequency changes to 120 Hz, as indicated. In this case, a period from the 2 nd< pulse A2 to a 3 rd< pulse A3 is 1 / 120, and a corresponding frequency is 120 Hz. The frequency of the TE signal changes with the theoretical screen refresh frequency in a timely manner, and a frequency at which the SOC sends a data signal also changes with the theoretical screen refresh frequency in a timely manner.

[0077] However, widths of the 1 st< pulse A1, the 2 nd< pulse A2, the 3 rd< pulse A3, a 4 th< pulse A4, and the like are narrow, a range of an occupied time period is quite narrow, and most time periods are ineffective pulse time periods. Therefore, as shown in FIG. 4D, a probability that a moment at which the theoretical screen refresh frequency changes falls exactly within a pulse width period (for example, a position indicated by the arrow) is quite low. In most cases, the moment at which the theoretical screen refresh frequency changes falls within an ineffective pulse time period, as indicated by an arrow in FIG. 4E.

[0078] As shown in FIG. 4E, at a 1 st< pulse A1 and a 2 nd< pulse A2 of the TE signal, the screen refresh frequency is 90 Hz, and the frequency of the TE signal is also 90 Hz. However, after the 2 nd< pulse A2 (at a moment indicated by the arrow in FIG. 4E), the screen refresh frequency changes to 120 Hz, as indicated. In this case, a period from the 2 nd< pulse A2 to a 3 rd< pulse A3 should be 1 / 120, and a corresponding frequency should be 120 Hz. However, when the foregoing CMD driving solution is used, the period from the 2 nd< pulse A2 to the 3 rd< pulse A3 is still 1 / 90, the corresponding frequency is 90 Hz, and a frequency at which the SOC sends a data signal is also 90 Hz. After the 3 rd< pulse A3, the frequency of the TE signal changes to 120 Hz, and the frequency at which the SOC sends the data signal changes to 120 Hz. The frequency at which the SOC sends the data signal can keep up with the change in the theoretical screen refresh frequency with a one-frame delay.

[0079] Therefore, in the foregoing CMD driving solution, in the case of random switching of the screen refresh frequency, it cannot be ensured that the frequency of the TE signal is immediately switched (steplessly switched) along with the screen refresh frequency. In some scenarios, a change in the frequency of the TE signal takes effect with a one-frame delay. Consequently, an error occurs in related driver interaction timing logic, and a related change in the screen refresh frequency cannot be followed or responded to in a timely manner. In addition, processing logic needs to be compatible with a case in which the frequency of the TE signal changes and a case in which the frequency of the TE signal does not change. This greatly increases complexity of logic processing.

[0080] An embodiment of this application further provides a display drive 20 and an SOC. The display drive and the SOC are used in the foregoing electronic device 1, to alleviate a case in which a change in a frequency of a TE signal takes effect with a one-frame delay in some scenarios in the foregoing CMD driving solution.

[0081] For ease of description, an example in which the display drive 20 is a DDIC and the display drive 20 is coupled to the SOC through an MIPI interface is still used below for illustration.

[0082] In some embodiments, the DDIC is configured to send a TE signal, and a frequency of the TE signal sent by the DDIC is a first fixed frequency.

[0083] Alternatively, this is understood as that the frequency of the TE signal sent by the DDIC does not change with a screen refresh frequency. Regardless of how the screen refresh frequency of the electronic device 1 changes, the frequency of the TE signal is always the first fixed frequency.

[0084] For example, the first fixed frequency is a common multiple of a plurality of screen refresh frequencies supported by the electronic device 1. For example, the first fixed frequency is a lowest common multiple of the plurality of screen refresh frequencies supported by the electronic device 1. The first fixed frequency is the lowest common multiple of the plurality of screen refresh frequencies, and a requirement of the electronic device 1 may be met by using a minimum first fixed frequency, to reduce power consumption of the electronic device 1.

[0085] In a possible solution, the screen refresh frequencies supported by the electronic device 1 include 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, and 120 Hz. In this case, a value of the first fixed frequency may be (360×m) Hz, where m is a positive integer. For example, the value of the first fixed frequency is 360 Hz or 720 Hz. 360 Hz is a lowest common multiple of 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, and 120 Hz.

[0086] The common multiple and the lowest common multiple are defined as follows: In terms of the common multiple (common multiple), if two or more natural numbers have same multiples, the multiples are common multiples of the natural numbers. A smallest one of the common multiples is referred to as a lowest common multiple (lowest common multiple) of the integers.

[0087] For ease of understanding and distinguishing, several frequencies mentioned in this embodiment of this application are denoted as follows: f is the screen refresh frequency of the electronic device 1, f1 is the first fixed frequency, f2 is a variable frequency, and f3 is a second fixed frequency.

[0088] In some embodiments, the SOC is configured to receive the TE signal. For example, the SOC is coupled to the DDIC through the MIPI interface, so that the SOC can receive the TE signal sent by the DDIC.

[0089] The SOC is further configured to output display data at the variable frequency f2, where the variable frequency f2 at which the SOC outputs the display data is affected by a pulse of the first fixed frequency f1.

[0090] The display data output by the SOC may be any type of data that can be output by an SOC to a DDIC in the related technology. This is not limited in this embodiment of this application. For example, the display data may include image data or a self-refresh instruction.

[0091] FIG. 5 and FIG. 6 are diagrams of pulses of transmit frequencies of a TE signal and display data according to an embodiment of this application.

[0092] In some embodiments, as shown in FIG. 5, f1=n×f2, where n is a ratio of the first fixed frequency f1 to a screen refresh frequency f of a current frame, and n varies with the screen refresh frequency f. The screen refresh frequency f in this embodiment of this application represents a theoretical screen refresh frequency of an electronic device 1, to be specific, a screen refresh frequency to which the electronic device 1 expects to switch in the current frame. The variable frequency f2 is a frequency at which an SOC actually sends display data, and is equivalent to an actual screen refresh frequency of the electronic device 1 in the current frame, to be specific, a screen refresh frequency to which the electronic device 1 actually switches in the current frame. The variable frequency f2 changes with the screen refresh frequency f in a timely manner, so that the actual screen refresh frequency changes with the theoretical screen refresh frequency in a timely manner.

[0093] Alternatively, this is understood as follows: A pulse period of the first fixed frequency f1 is a first pulse period T1, a pulse period of the variable frequency f2 is a second pulse period T2, and T2=n×T1. To be specific, n pulse periods of the TE signal correspond to one transmission of the display data. In other words, after n pulse periods of the TE signal, the SOC sends the display data once.

[0094] For example, the first fixed frequency f1 is 360 Hz.

[0095] As shown in FIG. 6, if the screen refresh frequency f of the current frame is 120 Hz, n=f1 / f=360 / 120=3. The variable frequency f2 of the current frame=f1 / n=360 / 3=120 Hz, which is the same as the screen refresh frequency f. To be specific, after three pulses of the TE signal, the display data is sent once.

[0096] If the screen refresh frequency f of the current frame is 90 Hz, n=f1 / f=360 / 90=4. The variable frequency f2 of the current frame=f1 / n=360 / 4=90 Hz, which is the same as the screen refresh frequency f. To be specific, after four pulses of the TE signal, the display data is sent once.

[0097] If the screen refresh frequency f of the current frame is 60 Hz, n=f1 / f=360 / 60=6. The variable frequency f2 of the current frame=f1 / n=360 / 6=60 Hz, which is the same as the screen refresh frequency f. To be specific, after six pulses of the TE signal, the display data is sent once.

[0098] As shown in FIG. 5, a screen refresh frequency f of a previous frame is 120 Hz, and a variable frequency f2 of the previous frame is 120 Hz. The screen refresh frequency f of the current frame switches to 90 Hz (for example, a position of an arrow in FIG. 5 indicates a switching moment), and the variable frequency f2 of the current frame may also directly switch to 120 Hz correspondingly, without waiting for a next frame to switch the variable frequency f2 to 120 Hz.

[0099] After the foregoing SOC and DDIC are used in the electronic device 1 provided in embodiments of this application, the DDIC is configured to send a TE signal whose frequency is a first fixed frequency f1 to the SOC, and the SOC is configured to receive the TE signal, and output display data to the DDIC at a variable frequency f2 based on the TE signal.

[0100] An embodiment of this application further provides a driving method for the electronic device 1. The driving method includes the following steps.

[0101] S1: The DDIC sends the TE signal whose frequency is the first fixed frequency f1.

[0102] For a manner of sending the TE signal by the DDIC, refer to related descriptions of the DDIC in the example in FIG. 3. Details are not described herein again.

[0103] S2: The SOC receives the TE signal, and outputs the display data to the DDIC at the variable frequency f2 based on the TE signal.

[0104] For a manner of outputting the display data by the SOC to the DDIC, refer to related descriptions of the SOC in the example in FIG. 3. Details are not described herein again.

[0105] In the electronic device 1 provided in embodiments of this application, the frequency of the TE signal sent by the DDIC is the first fixed frequency f1 that is a high frequency, and the first fixed frequency f1 is a common multiple of all screen refresh frequencies f that can be supported by the electronic device 1. In this case, the first fixed frequency f1 can be exactly divided by each screen refresh frequency f. A possible value of the variable frequency f2 is the same as a value of the screen refresh frequency f. Therefore, the first fixed frequency f1 can be exactly divided by each variable frequency f2. That is, f1 / f2=n. Correspondingly, a second pulse period T2 of the variable frequency f2 can be exactly divided by a first pulse period T1 of the first fixed frequency f1. That is, T2 / T1=n. To be specific, each second pulse period T2 is n times the first pulse period T1. After a screen refresh frequency f (namely, a theoretical screen refresh frequency) of a current frame changes, the variable frequency f2 only needs to synchronously change based on a quantity n of first pulse periods T1 that are intervals, without delaying by one frame based on a screen refresh frequency f corresponding to a previous frame. Therefore, the variable frequency f2 can respond to the change in the screen refresh frequency f in a timely manner, to quickly follow the change in the screen refresh frequency f, and change a value of the variable frequency f2 to the screen refresh frequency f. In this case, an actual screen refresh frequency of the electronic device 1 is also the screen refresh frequency f. In view of this, in this embodiment of this application, when the screen refresh frequency f of the electronic device 1 changes, the actual screen refresh frequency can also respond to an image refresh frequency (namely, the theoretical screen refresh frequency) of the SOC in a timely manner, to implement smooth stepless (seamless) switching between a plurality of screen refresh frequencies f. In addition, because smooth stepless switching can be performed in various scenarios, only one set of frame switching drive logic needs to be used, without a need to be compatible with a case in which a change in a transmit frequency of the SOC is delayed and a case in which a change in a transmit frequency of the SOC is not delayed. This reduces complexity of logic processing, enables a screen to change with an image, and implements stepless frame switching, and can further avoid a logic error caused by inconsistent driver interaction timing.

[0106] According to the driving method provided in this embodiment of this application, a screen can change with an image, and stepless frame switching can be implemented. A screen refresh rate can follow an image processing frequency (namely, a theoretical screen refresh frequency) of the SOC in real time, without additional interaction through an instruction for changing the screen refresh rate. Overall driving logic is simple and efficient.

[0107] Two examples are used below to describe the electronic device 1 and the driving method therefor provided in embodiments of this application.Example 1

[0108] An embodiment of this application provides a DDIC. As shown in FIG. 5, the DDIC is configured to continuously send a TE signal, and a frequency of the TE signal sent by the DDIC is a first fixed frequency.

[0109] For example, the first fixed frequency f1 is a common multiple of a plurality of screen refresh frequencies f supported by the electronic device 1. For example, the first fixed frequency f1 is a lowest common multiple of the plurality of screen refresh frequencies f supported by the electronic device 1.

[0110] In this example, an example in which the screen refresh frequencies f supported by the electronic device 1 include 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, and 120 Hz and a value of the first fixed frequency f1 of the TE signal is 360 Hz is used for illustration. In this case, a value of n may include 360, 36, 12, 4, and 3.

[0111] This embodiment of this application further provides an SOC. The SOC is configured to receive the TE signal, and output display data once after cumulatively receiving n pulses of the TE signal.

[0112] For example, in FIG. 5, after a 1 st< pulse B1 of the TE signal, the SOC sends the display data (image data) once. A screen refresh frequency f of a current frame is 120 Hz. The SOC learns that the display data may be sent once after three (360 / 120) pulses cumulated. Therefore, the SOC continues to receive the TE signal, and after three pulses cumulated, sends the display data (a self-refresh instruction) once after a 4 th< pulse B4 of the TE signal. After the SOC sends the self-refresh instruction, the screen refresh frequency of the current frame changes: f=90 Hz. The SOC learns that the display data may be sent once after four (360 / 90) pulses cumulated. Therefore, the SOC continues to receive the TE signal, and after four pulses cumulated, sends the display data (image data) once after an 8 th< pulse B8 of the TE signal. Therefore, after the screen refresh frequency f of the current frame changes, a transmit periodicity of the SOC changes correspondingly in a timely manner, to avoid a case that the change is delayed by one frame.

[0113] The change in the screen refresh frequency f is controlled by an upper-layer instruction of the electronic device 1, and synchronously, a change in a counting threshold of the SOC for pulses of the TE signal is also synchronously controlled by the upper-layer instruction.

[0114] In some embodiments, the value of the first fixed frequency f1 is greater than a maximum screen refresh frequency f among the screen refresh frequencies f supported by the electronic device 1. Alternatively, this is understood as that the value of n is greater than 1.

[0115] This can alleviate a problem that the SOC is likely to be triggered to send the display data in an error case due to an excessively small value of n.

[0116] FIG. 7 is a flowchart of a driving method for an electronic device according to an embodiment of this application.

[0117] When the foregoing DDIC and SOC are used in an electronic device 1, the driving method for an electronic device includes the following steps.

[0118] S10: The DDIC continuously sends a TE signal.

[0119] S20: The SOC receives the TE signal, and outputs display data to the DDIC once after cumulatively receiving n pulses of the TE signal.

[0120] A first fixed frequency f1 of the TE signal is 360 Hz. Image sending logic of the SOC is as follows: After receiving n pulses of a specified TE signal, the SOC is triggered to send image data or send a self-refresh instruction. n is a ratio of the first fixed frequency f1 to a screen refresh frequency f (or referred to as a target refresh rate) of a current frame.

[0121] For example, in FIG. 5, when the screen refresh frequency f is 120 Hz, n=3. The SOC performs internal counting. After receiving three pulses of the TE signal, the SOC is triggered to send the display data. When the screen refresh frequency f is 90 Hz, n=4. The SOC performs internal counting. After receiving four pulses of the TE signal, the SOC is triggered to send the display data.

[0122] In this embodiment of this application, switching may be randomly performed, based on an application scenario without a rule, between a plurality of screen refresh frequencies f supported by the electronic device 1. That is, the screen refresh frequency f of the current frame is switchable without a rule. For example, a screen refresh frequency f of a previous frame is 120 Hz, the screen refresh frequency f of the current frame may be any one of 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, or 120 Hz, and a screen refresh frequency f of a next frame may also be any one of 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, or 120 Hz. The screen refresh frequency f is not limited to only increasing or only decreasing.

[0123] In the electronic device 1 provided in this embodiment of this application, logic of interaction between the DDIC and the SOC is as follows: The DDIC continuously sends the TE signal at the first fixed frequency f1, and the SOC internally counts n pulses of the TE signal as a condition for triggering the SOC to send the display data. A change in a refresh frequency is implemented between the DDIC and the SOC directly through internal counting by the SOC, and the change in the refresh frequency does not need to be implemented by using a CMD. Logic of sending the TE signal is simple, and control difficulty is reduced.

[0124] FIG. 8 is a diagram of waveforms of a TE signal and a light-emitting control start (STV-EM) signal according to an embodiment of this application.

[0125] In some embodiments, the DDIC is further configured to send an STV-EM signal.

[0126] For example, the DDIC is configured to send an STV-EM signal to a display 10 of the electronic device 1. A gate drive circuit 12 in the display 10 may receive the STV-EM signal, and provide an EM signal for each row of pixel circuit 111 based on the STV-EM signal.

[0127] For example, as shown in FIG. 8, a frequency of the STV-EM signal is a second fixed frequency f3, and the second fixed frequency f3 is an integer multiple of the first fixed frequency f1. In FIG. 8, an example in which the second fixed frequency f3 is equal to the first fixed frequency f1 is used for illustration.

[0128] As shown in FIG. 7, the driving method for an electronic device further includes the following step.

[0129] S30: The DDIC sends the STV-EM signal to the display 10.

[0130] Certainly, before the DDIC sends the STV-EM signal to the display 10, the DDIC may further send an STV-SCAN signal, a data voltage Vdata, and the like to the display 10. In this embodiment of this application, only a part of steps in the driving method for an electronic device are described as an example, and the driving method for an electronic device may further include other steps.

[0131] The second fixed frequency f3 of the STV-EM signal is set to be an integer multiple of the first fixed frequency f1 of the TE signal, so that a first pulse period T1 of the TE signal is an integer multiple of a pulse period T3 of the STV-EM signal. In this case, a quantity of pulses of the STV-EM signal that correspond to each pulse period of the TE signal is fixed, to avoid a case that pulse periods correspond to different quantities of pulses of the STV-EM signal. Therefore, a pulse period of the TE signal may be considered as a minimum repetition unit with fixed luminance. During switching of the screen refresh frequency f, luminance of the display 10 may be kept consistent to improve display effect.

[0132] In the electronic device 1 provided in this embodiment of this application, when the screen refresh frequency f changes, provided that a cumulative quantity of pulses of the TE signal immediately changes, a variable frequency f2 can respond to the change in the screen refresh frequency f in a timely manner and quickly follow the change in the screen refresh frequency f. In this way, an actual screen refresh frequency can respond to an image refresh frequency (namely, a theoretical screen refresh frequency) of the SOC in a timely manner, to implement smooth stepless (seamless) switching between the plurality of screen refresh frequencies f. The electronic device is driven by using the driving method provided in this embodiment of this application, to cause a screen to change with an image, and implement stepless frame switching. A screen refresh rate can follow an image processing frequency (namely, the theoretical screen refresh frequency) of the SOC in real time, without additional interaction through an instruction for changing the screen refresh rate. Overall driving logic is simple and efficient.Example 2

[0133] FIG. 9 and FIG. 10 are other diagrams of pulses of transmit frequencies of a TE signal and display data according to an embodiment of this application.

[0134] An embodiment of this application provides a DDIC. As shown in FIG. 9, the DDIC is configured to intermittently send a TE signal.

[0135] For example, the DDIC skips sending the TE signal in n2 pulse periods after sending n1 pulses of the TE signal, and a period of the n1 sent pulses is the same as the n2 pulse periods in which no TE signal is sent. That is, regardless of sending the TE signal or suspending sending the TE signal by the DDIC, pulse time is calculated by using a first fixed frequency f1. A manner of calculating the first fixed frequency f1 is the same as that in Example 1.

[0136] Herein, that the DDIC skips sending the TE signal may be that the DDIC does not execute an instruction for sending the TE signal, or may be that the DDIC executes an instruction for sending the TE signal but the TE signal is not received by the SOC in the n2 pulse periods.

[0137] This embodiment of this application further provides an SOC. The SOC is configured to receive the TE signal, and output display data once after cumulatively receiving n1 pulses of the TE signal.

[0138] n1+n2=n, where n2 is a fixed positive integer and is less than a minimum value of n.

[0139] The minimum value of n means that a plurality of values of n are obtained by dividing the first fixed frequency f1 by each screen refresh frequency f supported by the electronic device 1, and a smallest one of the plurality of values of n is the minimum value of n in this embodiment of this application. For example, a value of n may include 360, 36, 12, 4, and 3. In this case, n2 is less than 3. In FIG. 9, n2=2 is used as an example for illustration.

[0140] That n2 is a fixed positive integer means that, for an electronic device 1, after a value of n2 is determined in a range less than the minimum value of n, the value of n2 remains unchanged regardless of how the screen refresh frequency f is switched. However, for different electronic devices 1, the value of n2 may vary.

[0141] For example, in FIG. 9, n2=2. After a 1 st< pulse C1 of the TE signal, the SOC sends the display data (image data) once. A screen refresh frequency f of a current frame is 120 Hz. The SOC learns that the display data may be sent once after n1=1 (3-2) pulse cumulated. The SOC continues to receive the TE signal. However, after the 1 st< pulse C1, no TE signal is sent in subsequent two pulse intervals, and the TE signal is re-sent at a moment corresponding to a 4 th< pulse C4. The SOC starts cumulation from the 4 th< pulse C4. After cumulatively receiving one pulse, the SOC sends the display data (a self-refresh instruction) once after the 4 th< pulse C4 of the TE signal. After the SOC sends the self-refresh instruction, the screen refresh frequency of the current frame changes: f=90 Hz. The SOC learns that the display data may be sent once after n1=2 (4-2) pulses cumulated. The SOC continues to receive the TE signal. However, after the 4 th< pulse C4, no TE signal is sent in subsequent two pulse intervals, and the TE signal is re-sent at a moment corresponding to a 7 th< pulse C7. The SOC starts cumulation from the 7 th< pulse C7. After cumulatively receiving two pulses, the SOC sends the display data (image data) once after an 8 th< pulse B8 of the TE signal. Therefore, after the screen refresh frequency f of the current frame changes, a transmit periodicity of the SOC changes correspondingly in a timely manner, to avoid a case that the change is delayed by one frame.

[0142] As shown in FIG. 10, for example, the screen refresh frequency f is 120 Hz. If the screen refresh frequency f remains unchanged, the SOC keeps sending the display data once after cumulatively receiving one pulse.

[0143] FIG. 11 is a flowchart of a driving method for an electronic device according to an embodiment of this application.

[0144] When the foregoing DDIC and SOC are used in an electronic device 1, the driving method for an electronic device includes the following steps.

[0145] S100: The DDIC skips sending a TE signal in n2 pulse periods after sending n1 pulses of the TE signal.

[0146] S200: The SOC is configured to receive the TE signal, and output display data once after cumulatively receiving n1 pulses of the TE signal.

[0147] A first fixed frequency f1 of the TE signal is 360 Hz. Image sending logic of the SOC is as follows: After receiving n-n2 pulses of a specified TE signal, the SOC is triggered to send image data or send a self-refresh instruction. n is a ratio of the first fixed frequency f1 to a screen refresh frequency f (or referred to as a target refresh rate) of a current frame, and n2 is a fixed positive integer less than a minimum value of n.

[0148] For example, in FIG. 9, when the screen refresh frequency f is 120 Hz, n=3, n2=2, and n=1. The SOC performs internal counting. After receiving one pulse of the TE signal, the SOC is triggered to send the display data. The DDIC sends no TE signal during screen refreshing. When the screen refresh frequency f is 90 Hz, n=4, n2=2, and n=2. The SOC performs internal counting. After receiving two pulses of the TE signal, the SOC is triggered to send the display data.

[0149] In the electronic device 1 provided in this embodiment of this application, logic of interaction between the DDIC and the SOC is as follows: The DDIC keeps intermittently sending the TE signal at the first fixed frequency f1, and the SOC internally counts n1 pulses of the TE signal as a condition for triggering the SOC to send the display data.

[0150] FIG. 12 is a diagram of waveforms of a TE signal and a light-emitting control start (STV-EM) signal according to an embodiment of this application.

[0151] In some embodiments, the DDIC is further configured to send an STV-EM signal.

[0152] As shown in FIG. 11, the driving method for an electronic device further includes the following step.

[0153] S300: The DDIC sends an STV-EM signal to a display 10.

[0154] In the electronic device 1 provided in this embodiment of this application, when the screen refresh frequency f changes, provided that a cumulative quantity of pulses of the TE signal immediately changes, a variable frequency f2 can respond to the change in the screen refresh frequency f in a timely manner and quickly follow the change in the screen refresh frequency f. In this way, an actual screen refresh frequency can respond to an image refresh frequency (namely, a theoretical screen refresh frequency) of the SOC in a timely manner, to implement smooth stepless (seamless) switching between a plurality of screen refresh frequencies f. In addition, the DDIC intermittently sends the TE signal. After the SOC is triggered to send the display data, the DDIC no longer sends the TE signal to the SOC, and the SOC also suspends counting, and restarts counting after receiving the TE signal next time. This can reduce a probability that a frequency (the variable frequency f2) at which the SOC sends the display data conflicts with the screen refresh frequency f of the current frame due to a counting error. This can reduce a requirement on system stability of the SOC, and eliminate abnormal display caused by a conflict between the variable frequency f2 and the screen refresh frequency f of the current frame that occurs due to an occasional stability issue. The electronic device is driven by using the driving method provided in this embodiment of this application, to cause a screen to change with an image, and implement stepless frame switching. A screen refresh rate can follow an image processing frequency (namely, the theoretical screen refresh frequency) of the SOC in real time, without additional interaction through an instruction for changing the screen refresh rate. Overall driving logic is simple and efficient.

[0155] A computer program corresponding to the driving method for an electronic device provided in embodiments of this application may be stored at a hardware abstraction layer (hardware abstraction layer, HAL) of the electronic device 1, or may be stored in a kernel (kernel) of the electronic device 1.

[0156] An embodiment of this application further provides a computer-readable medium. The computer-readable medium stores a computer program. When the computer program is executed by a processor, the foregoing driving method for an electronic device is implemented. An embodiment of this application provides a computer program product including instructions. When the computer program product is run on an electronic device, the electronic device is enabled to perform the foregoing driving method for an electronic device.

[0157] The computer-readable medium may be a read-only memory (read-only memory, ROM) or another type of static storage device that can store static information and instructions, a random access memory (random access memory, RAM) or another type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (electrically erasable programmable read-only memory, EEPROM), or any other medium that can be used to carry or store expected program code in a form of an instruction or a data structure and that is accessible a computer, but is not limited thereto. The memory may exist independently, and is connected to the processor through a communication bus. The memory may alternatively be integrated with the processor.

[0158] All or some of the foregoing embodiments may be implemented by software, hardware, firmware, or any combination thereof. When the embodiments are implemented by a software program, all or some of the embodiments may be implemented in a form of a computer program product. The computer program product includes one or more computer instructions. When computer-executable instructions are loaded and executed on a computer, all or some of the processes or the functions according to embodiments of this application are generated. The computer may be a general-purpose computer, a dedicated computer, a computer network, or another programmable apparatus. The computer instructions may be stored in a computer-readable storage medium, or may be transmitted from one computer-readable storage medium to another computer-readable storage medium.

[0159] The foregoing descriptions are merely specific implementations of this application, but are not intended to limit the protection scope of this application. Any variation or replacement within the technical scope disclosed in this application shall fall within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

1. An electronic device, comprising a display drive and a processor, wherein the display drive is configured to send a tearing effect, TE signal, wherein a frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of a plurality of screen refresh frequencies supported by the electronic device; and the processor is configured to receive the TE signal, and output display data to the display drive at a variable frequency, wherein f1=n×f2, wherein f1 is the first fixed frequency, f2 is the variable frequency of a current frame, n is a ratio of the first fixed frequency to a screen refresh frequency of the current frame, and n varies with the screen refresh frequency.

2. The electronic device according to claim 1, wherein the display drive is configured to continuously send the TE signal; and the processor is configured to output the display data to the display drive once after cumulatively receiving n pulses of the TE signal.

3. The electronic device according to claim 1, wherein the display drive is configured to skip sending the TE signal in n2 pulse periods after sending n1 pulses of the TE signal; and the processor is configured to output the display data to the display drive once after cumulatively receiving n1 pulses of the TE signal, wherein n1+n2=n, wherein n2 is a fixed positive integer and is less than a minimum value of n.

4. The electronic device according to any one of claims 1 to 3, wherein the screen refresh frequency of the current frame is switchable without a rule.

5. The electronic device according to any one of claims 1 to 4, wherein the electronic device further comprises a display; and the display drive is further configured to send a light-emitting control start STV-EM signal to the display, wherein a frequency of the STV-EM signal is a second fixed frequency, and the second fixed frequency is an integer multiple of the first fixed frequency.

6. A driving method for an electronic device, wherein the electronic device comprises a display drive and a processor; and the driving method comprises: sending, by the display drive, a tearing effect TE signal, wherein a frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of a plurality of screen refresh frequencies supported by the electronic device; and receiving, by the processor, the TE signal, and outputting display data to the display drive at a variable frequency, wherein f1=n×f2, wherein f1 is the first fixed frequency, f2 is the variable frequency of a current frame, n is a ratio of the first fixed frequency to a screen refresh frequency of the current frame, and n varies with the screen refresh frequency.

7. The driving method according to claim 6, wherein the display drive continuously sends the TE signal; and the processor outputs the display data to the display drive once after cumulatively receiving n pulses of the TE signal.

8. The driving method according to claim 6, wherein the display drive skips sending the TE signal in n2 pulse periods after sending n1 pulses of the TE signal; and the processor outputs the display data to the display drive once after cumulatively receiving n1 pulses of the TE signal, wherein n1+n2=n, wherein n2 is a fixed positive integer and is less than a minimum value of n.

9. The driving method according to any one of claims 6 to 8, wherein the screen refresh frequency of the current frame is switchable without a rule.

10. The driving method according to any one of claims 6 to 9, wherein the electronic device further comprises a display; and the driving method comprises: sending, by the display drive, a light-emitting control start STV-EM signal to the display, wherein a frequency of the STV-EM signal is a second fixed frequency, and the second fixed frequency is an integer multiple of the first fixed frequency.

11. A display drive, used in an electronic device, wherein the display drive is configured to send a tearing effect TE signal, wherein a frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of a plurality of screen refresh frequencies supported by the electronic device; and the display drive is further configured to receive display data at a variable frequency, wherein f1=n×f2, wherein f1 is the first fixed frequency, f2 is the variable frequency of a current frame, n is a ratio of the first fixed frequency to a screen refresh frequency of the current frame, and n varies with the screen refresh frequency.

12. The display drive according to claim 11, wherein the display drive is configured to continuously send the TE signal.

13. The display drive according to claim 11, wherein the display drive is configured to skip sending the TE signal in n2 pulse periods after sending n1 pulses of the TE signal, wherein n2 is a fixed integer, and n1 varies with the screen refresh frequency.

14. The display drive according to any one of claims 11 to 13, wherein the display drive is further configured to send a light-emitting control start STV-EM signal, wherein a frequency of the STV-EM signal is a second fixed frequency, and the second fixed frequency is an integer multiple of the first fixed frequency.

15. A processor, used in an electronic device, wherein the processor is configured to receive a tearing effect TE signal, wherein a frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of a plurality of screen refresh frequencies supported by the electronic device; and the processor is further configured to output display data at a variable frequency, wherein f1=n×f2, wherein f1 is the first fixed frequency, f2 is the variable frequency of a current frame, n is a ratio of the first fixed frequency to a screen refresh frequency of the current frame, and n varies with the screen refresh frequency.

16. The processor according to claim 15, wherein the processor is configured to output the display data once after cumulatively receiving n pulses of the TE signal.

17. The processor according to claim 15, wherein the processor is configured to output the display data once after cumulatively receiving n1 pulses of the TE signal, wherein n-n1 is a fixed positive integer.

18. A computer-readable medium, wherein the computer-readable medium stores a computer program, and when the computer program is run on an electronic device, the electronic device is enabled to perform the driving method according to any one of claims 6 to 10.

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