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

By sending fixed frequency TE signals to the display driver and receiving variable frequency output by the processor, the problem of difficult screen refresh frequency in electronic devices to respond in time is solved, timely response and logical simplification of screen refresh frequency is achieved, and power consumption of electronic devices is reduced.

CN118918863BActive Publication Date: 2025-09-02HUAWEI TECH CO LTD

Patent Information

Application Number
CN202310878046.2
Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Filing Date
2023-07-17
Publication Date
2025-09-02
Estimated Expiration
2043-07-17

AI Technical Summary

Technical Problem

In the prior art, the actual screen refresh frequency of the electronic device is difficult to respond to the processor's image refresh frequency in a timely manner, resulting in delays and logic errors when the screen refresh frequency changes, increasing the complexity of the driving interaction timing.

Method used

The display driver is used to send a fixed frequency TE signal, and the processor receives and outputs the display data at variable frequency. The fixed frequency is a common multiple of the multiple screen refresh frequency. The timely response of the screen refresh frequency is achieved through internal counting, simplifying the driving logic and reducing complexity.

Benefits of technology

The screen refresh frequency is realized in a timely manner and the processor image refresh frequency is avoided, delay and logic errors are avoided, the complexity of the driver interaction timing is reduced, and the power consumption of electronic devices is reduced.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN118918863B_ABST
    Figure CN118918863B_ABST
Patent Text Reader

Abstract

Embodiments of the present application provide an electronic device and its driving method, display driver, and processor, relating to the field of electronic technology. These devices are used to ensure that the actual screen refresh rate can promptly respond to the image refresh rate of a core processing chip, such as an upper-layer SOC. The electronic device includes a display driver IC (DDIC) and a system-on-chip (SOC). The display driver IC (DDIC) is used to transmit a time-of-flight (TE) signal. The TE signal has a first fixed frequency f1, where f1 is a common multiple of the multiple screen refresh frequencies f supported by the electronic device. For example, if the electronic device supports 60 Hz, 90 Hz, and 120 Hz, then f1 is 360 Hz. The SOC is used to receive the TE signal and output display data to the display driver IC at a variable frequency f2. Here, f1 = n * f2. Therefore, the pulse period of f1 is the first pulse period T1, and the pulse period of f2 is the second pulse period T2, where T2 = n * T1. n is the ratio of f1 to the current frame's f. The second pulse period T2 of the current frame f2 is always n times the first pulse period T1 of f1, meaning that display data is always transmitted once every n T1s. n varies with the screen f.
Need to check novelty before this filing date? Find Prior Art

Description

Technical Field

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

[0002] With the development of display technology, high-frame-rate electronic devices are becoming a market trend. These devices often feature the ability to switch between different refresh rates based on different usage scenarios. For example, the refresh rate can be switched between 1Hz, 10Hz, 20Hz, 60Hz, 90Hz, and 120Hz.

[0003] Currently, there are two main ways to transmit display data to the display screen of an electronic device: video mode and command mode (CMD). In command mode, a tear effect (TE) signal that varies with the screen refresh rate is required to align the processor's display data transmission frequency with the display driver's reception frequency, ensuring that the actual screen refresh rate can promptly respond to the processor's image refresh rate (i.e., the theoretical screen refresh rate).

[0004] However, how to make the actual screen refresh frequency respond to the image refresh frequency of the processor in a timely manner is a technical problem that those skilled in the art urgently need to solve. Summary of the Invention

[0005] Embodiments of the present application provide an electronic device and a driving method thereof, a display driver, and a processor, which are used to enable the actual screen refresh frequency to respond promptly to the image refresh frequency of the processor (that is, the theoretical screen refresh frequency).

[0006] To achieve the above objectives, this application adopts the following technical solutions:

[0007] According to a first aspect of an embodiment of the present application, an electronic device is provided, comprising a display driver and a processor. The display driver may be, for example, a DDIC, and the display driver is configured to send a TE signal, wherein the frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of multiple 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, then the first fixed frequency is 360 Hz. The processor is configured to receive the TE signal and output display data to the display driver at a variable frequency. Wherein, f1=n*f2, f1 is the first fixed frequency, and f2 is the variable frequency of the current frame. That is, the pulse period of the first fixed frequency f1 is the first pulse period T1, the pulse period of the variable frequency f2 is the second pulse period T2, and T2=n*T1. n is the ratio of the first fixed frequency to the 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, that is, display data is always sent once after n T1s. n changes with the change of the screen refresh frequency and is a positive integer.

[0008] In the electronic device provided in the embodiment of the present application, the frequency of the TE signal sent by the display driver is a high-frequency first fixed frequency f1, and the first fixed frequency f1 is a common multiple of all screen refresh frequencies f that the electronic device can support. Then, the first fixed frequency f1 is divisible by each screen refresh frequency f, that is, f1 / f=n. And the first fixed frequency f1 is also divisible by each variable frequency f2. That is, f1 / f2=n. Correspondingly, the second pulse period T2 of the variable frequency f2 is divisible by the first pulse period T1 of the first fixed frequency f1. That is, T2 / T1=n. In other words, each second pulse period T2 is n times the first pulse period T1. After the screen refresh frequency f of the current frame (that is, the theoretical screen refresh frequency) is changed, there is no need to delay the screen refresh frequency f corresponding to the previous frame. The variable frequency f2 only needs to synchronize the number n of the first pulse periods T1 of the change interval. Therefore, the variable frequency f2 can respond to the change of the screen refresh frequency f in a timely manner, quickly follow the change of the screen refresh frequency f, and change the value of the variable frequency f2 to the screen refresh frequency f, then the actual screen refresh frequency of the electronic device is also the screen refresh frequency f. Based on this, in the embodiment of the present application, when the screen refresh frequency f of the electronic device changes, the actual screen refresh frequency can respond to the image refresh frequency of the processor (that is, the theoretical screen refresh frequency) in a timely manner, and realize smooth and infinite switching between multiple screen refresh frequencies f. Moreover, since smooth and infinite switching can be achieved in various scenarios, a set of frame cutting drive logic can be adopted, and there is no need to delay or not delay the frequency change sent by the compatible processor, which reduces the complexity of the logic processing, realizes the screen following the image, infinite frame change, and can also avoid logical errors caused by inconsistent drive interaction timing.

[0009] In a possible implementation, the display driver is configured to continuously send the TE signal; and the processor is configured to output display data to the display driver once after accumulating n pulses of the TE signal.

[0010] In other words, the interaction logic between the display driver and the processor is as follows: the display driver continuously sends a TE signal with a fixed frequency, while the processor internally counts n TE signal pulses as a trigger for the processor to send display data. The display driver and processor implement refresh frequency changes directly through the processor's internal count, eliminating the need for a CMD command. This TE signal transmission logic is simple, making control easier.

[0011] In one possible implementation, the display driver is configured to send n1 pulses of a TE signal and then not send a TE signal within an n2 pulse period. During the n1 pulse period, the display screen refreshes the data received by the display driver onto the display screen. During this process, if the SOC sends data again, a data conflict may occur, causing abnormal display such as a distorted screen. The processor is configured to output display data to the display driver once after receiving a cumulative n1 pulses of the TE signal. Here, n1+n2=n, and n2 is a fixed positive integer that is less than the minimum value of n.

[0012] That is, the display driver intermittently sends the TE signal, and after triggering the processor to send display data, it no longer sends the TE signal to the processor, and the processor pauses counting until it receives the next TE signal, at which point the counting restarts. This can avoid secondary data transmission between the SOC and DDIC when the display driver transmits display data to the display screen, and can reduce the probability that the frequency (variable frequency) of sending display data by the processor conflicts with the current frame screen refresh frequency due to counting errors. This can reduce and minimize the requirements for processor system stability, while eliminating occasional stability issues caused by conflicts between the variable frequency and the current frame screen refresh frequency, thereby causing abnormal displays.

[0013] In one possible implementation, the first fixed frequency is the least common multiple of multiple screen refresh frequencies supported by the electronic device. The first fixed frequency being the least common multiple of multiple screen refresh frequencies can meet the needs of the electronic device with the minimum first fixed frequency, thereby reducing power consumption of the electronic device.

[0014] In a possible implementation, the screen refresh rate of the current frame can be switched irregularly. The electronic device provided in this application can be applied to various application scenarios.

[0015] In one possible implementation, the electronic device further includes a display screen; and the display driver is further configured to send a light emission control start STV-EM signal to the display screen, wherein the frequency of the STV-EM signal is a second fixed frequency, which is an integer multiple of the first fixed frequency.

[0016] By setting the second fixed frequency of the STV-EM signal to an integer multiple of the first fixed frequency of the TE signal, the first pulse period of the TE signal is an integer multiple of the pulse period of the STV-EM signal. Consequently, the number of STV-EM signal pulses corresponding to each pulse period of the TE signal is fixed, and there will be no situation where the number of STV-EM signal pulses corresponding to each pulse period varies. Therefore, a pulse period of the TE signal can be considered a minimum repeating unit with a fixed brightness. When switching the screen refresh rate, the brightness of the display can remain consistent, improving the display quality.

[0017] The second aspect of the embodiment of the present application provides a driving method for an electronic device, the electronic device including a display driver and a processor; the driving method includes: the display driver sends a tearing effect TE signal; the frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of multiple screen refresh frequencies supported by the electronic device; the processor receives the TE signal and outputs display data to the display driver at a variable frequency; wherein, f1=n*f2, f1 is the first fixed frequency, f2 is the variable frequency of the current frame; n is the ratio of the first fixed frequency to the screen refresh frequency of the current frame, and n changes with the change of the screen refresh frequency. The driving method provided in the second aspect of the present application can realize the screen following the image movement and infinite frame change. The refresh rate of the screen can follow the image processing frequency of the processor (that is, the theoretical screen refresh frequency) in real time, and no additional interaction is required through the screen refresh rate change instruction. The entire driving logic is simple and efficient.

[0018] In a possible implementation, the display driver continuously sends the TE signal; after the processor has received n pulses of the TE signal cumulatively, it outputs display data to the display driver once.

[0019] In one possible implementation, after the display driver sends n1 pulses of the TE signal, it does not send the TE signal within an n2 pulse period; after the processor cumulatively receives n1 pulses of the TE signal, it outputs display data to the display driver once; wherein n1+n2=n, n2 is a fixed positive integer and is less than the minimum value of n.

[0020] In a possible implementation, the screen refresh frequency of the current frame may be switched irregularly.

[0021] In one possible implementation, the electronic device further includes a display screen; the driving method includes: a display driver sending a light emission control start STV-EM signal to the display screen, wherein the 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.

[0022] In a third aspect of an embodiment of the present application, a display driver is provided for use in an electronic device. The display driver is configured to transmit a tearing effect TE signal. The frequency of the TE signal is a first fixed frequency, which is a common multiple of multiple screen refresh frequencies supported by the electronic device. The display driver is also configured to receive display data at a variable frequency. Here, f1 = n*f2, where f1 is the first fixed frequency and f2 is the variable frequency of the current frame. n is the ratio of the first fixed frequency to the screen refresh frequency of the current frame, and n varies with the screen refresh frequency. When the display driver provided in the third aspect of the present application is applied to the electronic device provided in the first aspect, the effect of the electronic device provided in the first aspect can be achieved, which will not be described in detail here.

[0023] In a possible implementation, the display driver is configured to continuously send the TE signal.

[0024] In a possible implementation, the display driver is configured to send n1 pulses of the TE signal and then not send the TE signal within n2 pulse periods; wherein n2 is a fixed integer, and n1 changes with the screen refresh frequency.

[0025] In a possible implementation, the first fixed frequency is the least common multiple of multiple screen refresh frequencies supported by the electronic device.

[0026] In a possible implementation, the display driver is further configured to send a light emission control start STV-EM signal, where the 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.

[0027] The fourth aspect of the embodiments of the present application provides a processor for use in an electronic device; the processor is used to receive a tearing effect TE signal; the frequency of the TE signal is a first fixed frequency, which is a common multiple of multiple screen refresh frequencies supported by the electronic device; the processor is also used to output display data at a variable frequency; wherein f1 = n*f2, f1 is the first fixed frequency, f2 is the variable frequency of the current frame; n is the ratio of the first fixed frequency to the screen refresh frequency of the current frame, and n changes with the change of the screen refresh frequency. After the processor provided by the fourth aspect of the present application is applied to the electronic device provided by the first aspect, the effect of the electronic device provided by the first aspect can be achieved, which will not be repeated here.

[0028] In a possible implementation, the processor is configured to output display data once after accumulating n pulses of the TE signal.

[0029] In a possible implementation, the processor is configured to output display data once after accumulating n1 pulses of the TE signal, wherein n-n1 is a fixed positive integer.

[0030] In a possible implementation, the first fixed frequency is the least common multiple of multiple screen refresh frequencies supported by the electronic device.

[0031] According to a fifth aspect of the embodiments of the present application, a computer-readable medium is provided, which stores a computer program. When the computer program runs on an electronic device, the electronic device executes the driving method of any one of the second aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 An architecture diagram of an electronic device provided in an embodiment of the present application;

[0033] Figure 2 A schematic diagram of a sub-pixel topological structure provided in an embodiment of the present application;

[0034] Figure 3 An architecture diagram of an electronic device provided in an embodiment of the present application;

[0035] Figures 4A-4E A waveform diagram of a TE signal provided in an embodiment of the present application;

[0036] Figure 5 A pulse diagram of a TE signal and display data transmission frequency provided in an embodiment of the present application;

[0037] Figure 6 A pulse diagram of another TE signal and display data transmission frequency provided in an embodiment of the present application;

[0038] Figure 7 A flowchart of a method for driving an electronic device provided in an embodiment of the present application;

[0039] Figure 8 A waveform diagram of a TE signal and a STV-EM signal provided in an embodiment of the present application;

[0040] Figure 9 A pulse diagram of another TE signal and display data transmission frequency provided in an embodiment of the present application;

[0041] Figure 10 A pulse diagram of another TE signal and display data transmission frequency provided in an embodiment of the present application;

[0042] Figure 11 A flowchart of a method for driving an electronic device provided in an embodiment of the present application;

[0043] Figure 12 Another waveform diagram of a TE signal and an STV-EM signal provided in an embodiment of the present application. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0045] Hereinafter, the terms "second," "first," etc., are used for descriptive convenience only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature qualified as "second," "first," etc., may explicitly or implicitly include one or more of such features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0046] In addition, in the embodiments of the present application, directional terms such as "up", "down", "left", and "right" may be defined including but not limited to the orientation relative to the schematic placement of the components in the drawings. It should be understood that these directional terms may be relative concepts, which are used for relative descriptions and clarifications, and may change accordingly according to changes in the orientation of the components in the drawings.

[0047] In the embodiments of this application, unless otherwise specified or limited, the term "connection" should be understood in a broad sense. For example, "connection" can mean fixed connection, detachable connection, or integration; it can mean direct connection or indirect connection through an intermediate medium. In addition, the term "coupling" can mean direct electrical connection or indirect electrical connection through an intermediate medium. The term "contact" can mean direct contact or indirect contact through an intermediate medium.

[0048] In the embodiments of the present application, "and / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0049] The embodiment of the present application provides an electronic device. The electronic device is, for example, a consumer electronic product with a display function, a home electronic product, a vehicle-mounted electronic product, or a financial terminal product. Among them, consumer electronic products include mobile phones, tablet computers, laptop computers, e-readers, personal computers (PCs), personal digital assistants (PDAs), desktop displays, smart wearable products (for example, smart watches, smart bracelets), virtual reality (VR) electronic devices, augmented reality (AR) electronic devices, drones, etc. Home electronic products include smart door locks, televisions, remote controls, refrigerators, rechargeable small household appliances (for example, soymilk machines, sweeping robots), etc. Vehicle-mounted electronic products include car navigation systems, car high-density digital video discs (DVDs), etc. Financial terminal products include automated teller machines (ATMs), self-service terminals, etc. The embodiment of the present application does not impose any special restrictions on the specific forms of the above-mentioned electronic devices.

[0050] Figure 1 This is an architectural diagram of an electronic device provided in an embodiment of the present application.

[0051] Take the mobile phone as an example, Figure 1 As shown, the electronic device 1 includes a display screen 10 , a display driver 20 and a processor 30 . Figure 1 The electronic device 1 is taken as an example of a straight-screen mobile phone. The electronic device 1 may also be a folding-screen mobile phone. This embodiment of the present application is only an illustration.

[0052] In some embodiments, the display screen 10 may be an organic light emitting diode (OLED) display screen, which is capable of self-luminescence. Alternatively, in other embodiments, the display screen 10 may be a liquid crystal display (LCD). In this case, the electronic device further includes a backlight module for providing light to the display screen 10.

[0053] For any of the above display screens 10 , the display screen 10 includes an active display area (AA) 101 and a non-display area 102 located around the active display area 101 . The active display area 101 is used to display images and includes a plurality of sub-pixels 11 .

[0054] For ease of explanation, the above-mentioned multiple sub-pixels 11 are arranged in a matrix as an example in this application. Sub-pixels 11 arranged in a row along the horizontal direction X are called sub-pixels in the same row, and sub-pixels 11 arranged in a row along the vertical direction Y are called sub-pixels in the same column.

[0055] Figure 2 A schematic diagram of a sub-pixel topological structure provided in an embodiment of the present application.

[0056] The sub-pixel 11 is provided with a pixel circuit 111 for controlling the display of the sub-pixel 11. When the display screen 10 is an OLED display screen, Figure 2 As shown, the sub-pixel 11 also includes a light-emitting device L coupled to the pixel circuit 111. For example, the light-emitting device L is an OLED, with the anode (a) of the light-emitting device L coupled to the pixel circuit 111 and the cathode (c) coupled to the voltage terminal VSS. The pixel circuit 111 is used to drive the light-emitting device L to emit light.

[0057] The pixel circuit 111 includes a plurality of switching transistors (eg, Figure 2 transistors M1 and M2 as shown), a driver transistor (e.g., Figure 2 The transistor Td) and the capacitor Cst are shown.

[0058] by Figure 2 For example, when the transistor M1 is turned on under the control of the scan (SCAN) signal, the data voltage Vdata can be written into the driving transistor Td, so that the driving transistor Td generates a driving current I corresponding to the data voltage Vdata.

[0059] Since the light-emitting device L is an OLED, it is a current light-emitting device. Therefore, by controlling the size of the data voltage Vdata, the size of the driving current I can be controlled. Thus, after the driving current I flows through the light-emitting device L, the purpose of controlling the brightness of the light-emitting device L can be achieved.

[0060] After the driving transistor Td is turned on, the transistor M2 can control the on / off state of the current path formed between the voltage terminal VDD and the voltage terminal VSS under the control of the emission control (EM) signal, thereby controlling whether the driving current I can flow into the light emitting device L.

[0061] By using pulse width modulation (PWM), the duty ratio of the EM signal can be controlled, thereby controlling the effective conduction duration of the current path formed between the voltage terminal VDD and the voltage terminal VSS within each frame, that is, the effective duration of the driving current I flowing through the light-emitting device L, thereby achieving the purpose of controlling the light-emitting brightness of the light-emitting device L.

[0062] In some embodiments, the display screen 10 further includes a gate driver circuit 12, which is configured to provide the aforementioned SCAN and EM signals to the pixel circuits 111. For example, the gate driver circuit 12 includes a gate scanning module and a light emission control module. The gate scanning module is configured to receive a gate scanning start signal (STV-SCAN) provided by the display driver 20 and provide a SCAN signal to each row of pixel circuits 111 in a step-by-step manner. The light emission control module receives a light emission control start signal (STV-EM) provided by the display driver 20 and provide an EM signal to each row of pixel circuits 111 in a step-by-step manner. The gate driver circuit 12 can be integrated into the non-display area 102 of the display screen 10 using gate driver on array (GOA) technology.

[0063] Please continue to refer to Figure 1 In some embodiments, the display driver 20 in the electronic device 1 may be a display driver integrated circuit (DDIC). In this case, the display driver 20 may be bonded to the display screen 10 via bonding pads disposed in the non-display area 102 of the display screen 10.

[0064] In some embodiments, the processor 30 in the electronic device 1 may include an integrated circuit, a system on a chip (SOC), a microprocessor, etc.

[0065] The display driver 20 may be coupled to the SOC via a mobile industry processor interface (MIPI) interface, or alternatively, via other high-speed serial / deserial (SerDes) interfaces.

[0066] For the convenience of description, the following description is made by taking the display driver 20 as a DDIC, which is coupled to the SOC via a MIPI interface as an example.

[0067] Figure 3 This is an architectural diagram of an electronic device provided in an embodiment of the present application.

[0068] In some embodiments, as Figure 3 As shown, the DDIC includes a timing control unit (TCON) 21 , a processing unit 22 , a transceiver unit 23 , and a frame buffer unit 24 . The frame buffer unit 24 is coupled to the transceiver unit 23 and the processing unit 22 , respectively.

[0069] TCON21 is used to send a tearing effect (TE) signal. The TE signal is a square wave signal, and a high level of the TE signal is regarded as a valid signal of the TE signal.

[0070] In some embodiments, the SOC includes a graphics processing unit (GPU) 31, a 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 can be double data rate synchronous dynamic random access memory (DDR SDRAM) or system memory (SRAM).

[0071] The GPU 31 can generate display data for the Nth frame (e.g., frame N=1) through data rendering and 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 for the first frame generated by the GPU 31 is stored in the storage unit 33.

[0072] The display engine unit 32 is coupled to the storage unit 33 and can also be coupled to the TCON 21 of the DDIC via a MIPI interface. The display engine unit 32 is configured to receive the TE signal sent by the TCON 21 and, based on the TE signal, extract the stored display data for the Nth frame (e.g., the display data for the first frame described above) from the storage unit 33.

[0073] The display engine unit 32 is coupled to the DDIC via the MIPI interface. The display engine unit 32 sends the display data of the Nth frame to the DDIC via the MIPI interface.

[0074] The transceiver unit 23 in the DDIC is coupled to the MIPI interface. The transceiver unit 23 receives the display data of the Nth frame (e.g., the first frame) sent by the display engine unit 32 via the MIPI interface. The transceiver unit 23 is also coupled to the frame buffer unit 24. The transceiver unit 23 buffers the display data of the Nth frame (e.g., the first frame) in the frame buffer unit 24.

[0075] The processing unit 22 may extract the display data of the Nth frame (eg, the first frame) from the frame buffer unit 24 and generate a data voltage Vdata for controlling the display of each sub-pixel 11 according to the display data of the Nth frame (eg, the first frame).

[0076] The gate driving circuit 12 receives the horizontal synchronization signal (H-Sync), and the gate driving circuit 12 scans the sub-pixels 11 row by row (along the X direction) starting from the first row of sub-pixels 11 to turn on some transistors (e.g. Figure 2 transistor M1 in FIG).

[0077] After issuing the TE signal, TCON21 in the DDIC receives an external vertical synchronization signal (V-Sync). After a row of subpixels 11 is scanned, the data voltage Vdata generated by the DDIC for controlling the display of each subpixel 11 is transmitted via the data line (DL) to the pixel circuit 111 of each subpixel 11 in the row. The data voltage Vdata is written to the drive transistor Td via the turned-on transistor M1. This enables the drive transistor Td of the pixel circuit 111 to generate the drive current I used to drive the light-emitting device L to emit light.

[0078] The gate driving circuit 12 may drive the transistors (eg, Figure 2 The gate of the transistor M2 in the circuit provides the EM signal. When the EM signal is at a high level (taking the high level as a valid signal as an example), the Figure 2 The current path formed between the middle voltage terminal VDD and the voltage terminal VSS is turned on to control the light emitting device L to emit light.

[0079] The DDIC obtains the display data sent by the SOC through the MIPI interface to generate a data voltage Vdata. The data voltage Vdata is combined with the duty cycle of the EM signal to control the display screen 10 to display the Nth frame (for example, the first frame) image.

[0080] After the transceiver unit 23 in the DDIC receives the display data of the Nth frame, the DDIC performs the above display processing. Meanwhile, the GPU 31 in the SOC continues to generate the display data of the N+1th frame (eg, the second frame), thus looping the above process.

[0081] In summary, GPU 31 first generates display data for the Nth frame. While GPU 31 is generating display data for the N+1th frame, it also stores the display data for the Nth frame in storage unit 33. Under the control of the TE signal sent by the DDIC, the display engine unit 32 extracts the display data for the Nth frame from storage unit 33 and sends it to the transceiver unit 23 of the DDIC via the MIPI interface. The transceiver unit 23 can cache the display data for the Nth frame in the frame buffer unit 24. The processing unit 22 extracts the display data for the Nth frame from the frame buffer unit 24 and drives the display screen 10 to display the Nth frame image.

[0082] From the above description, it can be seen that whether the SOC sends display data to the DDIC is controlled by the TE signal sent by the DDIC, so that the frequency at which the SOC sends display data is consistent with the frequency at which the DDIC needs to receive display data, so that the actual screen refresh frequency of the electronic device 1 can respond to the image refresh frequency of the processor (that is, the theoretical screen refresh frequency) in a timely manner.

[0083] Figures 4A-4E A waveform diagram of a TE signal provided in an embodiment of the present application.

[0084] In some embodiments, a command mode (CMD) drive scheme is used to align signal transmission between the SOC and the DDIC. For example, the frequency of the TE signal transmitted by the DDIC changes with the theoretical screen refresh rate of the display 10. Alternatively, the frequency of the TE signal transmitted by the DDIC is the same as the screen refresh rate. By issuing a command to change the screen refresh rate in advance, the frequency of the TE signal is adjusted accordingly, thereby achieving the TE signal frequency changing with the theoretical screen refresh rate.

[0085] like Figures 4A-4C As shown, the screen refresh rates of display screen 10 are 60 Hz, 90 Hz, and 120 Hz, respectively. The frequencies of the TE signals emitted by the DDIC are also 60 Hz, 90 Hz, and 120 Hz, respectively. If the screen refresh rate remains unchanged from frame N to frame N+1, the TE signal emitted by the DDIC changes in accordance with the theoretical screen refresh rate of display screen 10, without affecting the display on display screen 10.

[0086] In some embodiments, the screen refresh rate from the Nth frame to the N+1th frame may change. Figure 4D As shown, at the first pulse A1 and the second pulse A2 of the TE signal, the screen refresh frequency is 90hz, and the frequency of the TE signal is also 90hz. And at the moment of the second pulse A2 ( Figure 4D At the moment indicated by the arrow, the screen refresh rate becomes 120 Hz. At this point, the period from the second pulse A2 to the third pulse A3 is 1 / 120, corresponding to a frequency of 120 Hz. The frequency of the TE signal changes in real time with the theoretical screen refresh rate, and the frequency of the data signal sent by the SOC also changes accordingly.

[0087] However, since the pulse widths of the first pulse A1, the second pulse A2, the third pulse A3, and the fourth pulse A4 are relatively narrow, the time intervals they occupy are very narrow, and most of the time intervals are non-effective pulse periods. Figure 4DAs shown in the figure, the probability of theoretical screen refresh frequency change falling exactly during the pulse width (such as the arrow point) is very small. In most cases, the theoretical screen refresh frequency change time falls during the non-effective pulse period, such as Figure 4E Where the arrow points.

[0088] like Figure 4E As shown, at the first pulse A1 and the second pulse A2 of the TE signal, the screen refresh frequency is 90hz, and the frequency of the TE signal is also 90hz. But after the second pulse A2 ( Figure 4E At the moment indicated by the arrow), the screen refresh frequency becomes 120hz. At this time, the period from the second pulse A2 to the third pulse A3 should be 1 / 120, and the corresponding frequency should be 120hz. However, when the above-mentioned CMD driving scheme is adopted, the period from the second pulse A3 to the third pulse A3 is still 1 / 90, and the corresponding frequency is 90hz, and the frequency of the data signal sent by the SOC is also 90hz. It was not until after the third pulse A3 that the frequency of the TE signal became 120hz, and the frequency of the data signal sent by the SOC became 90hz. The frequency of the data signal sent by the SOC needs to be delayed by one frame to keep up with the changes in the theoretical screen refresh frequency.

[0089] Therefore, with the aforementioned CMD drive solution, the TE signal frequency cannot ensure instant switching (infinite switching) with the screen refresh frequency due to arbitrary switching of the screen refresh frequency. In some scenarios, the TE signal frequency change will take effect with a delay of one frame. On the one hand, this will cause errors in the related driver interaction timing logic, and at the same time, the related screen refresh frequency changes will not respond in a timely manner. On the other hand, the processing logic needs to be compatible with both changes and no changes in the TE signal frequency, which greatly increases the complexity of the logic processing.

[0090] The embodiment of the present application further provides a display driver 20 and a SOC, which are applied to the above-mentioned electronic device 1 to improve the situation in which the TE signal frequency change is delayed by one frame in some scenarios in the above-mentioned CMD driving scheme.

[0091] For ease of description, the following example still uses the display driver 20 as a DDIC and the display driver 20 is coupled to the SOC via a MIPI interface.

[0092] In some embodiments, the DDIC is used to send a TE signal, and the frequency of the TE signal sent by the DDIC is a first fixed frequency.

[0093] Alternatively, it can be understood that the frequency of the TE signal sent by the DDIC does not change with the change of the screen refresh frequency. No matter how the screen refresh frequency of the electronic device 1 changes, the frequency of the TE signal is always the first fixed frequency.

[0094] For example, the first fixed frequency is a common multiple of multiple screen refresh frequencies supported by electronic device 1. For example, the first fixed frequency is the least common multiple of multiple screen refresh frequencies supported by electronic device 1. The first fixed frequency being the least common multiple of multiple screen refresh frequencies can meet the needs of electronic device 1 with the minimum first fixed frequency, thereby reducing power consumption of electronic device 1.

[0095] In one possible solution, the screen refresh rates supported by electronic device 1 include 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, and 120 Hz. Then, the 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 may be 360 ​​Hz, 720 Hz, etc. Among them, 360 Hz is the least common multiple of 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, and 120 Hz.

[0096] The definitions of common multiples and least common multiples are as follows: A common multiple is a number between two or more natural numbers that have the same multiples. The smallest common multiple is called the least common multiple of these integers.

[0097] To facilitate understanding and distinction, several frequencies mentioned in the embodiments of this application are marked: f is the screen refresh frequency obtained by the electronic device 1, f1 is the first fixed frequency, f2 is the variable frequency, and f3 is the second fixed frequency.

[0098] In some embodiments, the SOC is configured to receive the TE signal. For example, the SOC is coupled to the DDIC via a MIPI interface, so that the SOC receives the TE signal sent by the DDIC.

[0099] The SOC is further configured to output display data at a variable frequency f2, where the variable frequency f2 at which the SOC outputs display data is affected by the pulses of the first fixed frequency f1.

[0100] The display data output by the SOC can be any data that the SOC can output to the DDIC in the related art, and the embodiments of the present application are not limited thereto. For example, the display data can include image data or self-refresh instructions.

[0101] Figure 5 and Figure 6 A pulse diagram of a TE signal and display data transmission frequency provided in an embodiment of the present application.

[0102] In some embodiments, as Figure 5As shown, f1=n*f2. n is the ratio of the first fixed frequency f1 to the screen refresh frequency f of the current frame, and n changes with the change of the screen refresh frequency f. The screen refresh frequency f of the embodiment of the present application represents the theoretical screen refresh frequency of the electronic device 1, that is, the screen refresh frequency to which the electronic device 1 wishes to switch to in the current frame. The variable frequency f2 is the frequency at which the SOC actually sends display data, which is equivalent to the actual screen refresh frequency of the current frame of the electronic device 1, that is, the screen refresh frequency to which the electronic device 1 actually switches to in the current frame. The variable frequency f2 follows the changes in the screen refresh frequency f in a timely manner, so that the actual screen refresh frequency can follow the changes in the theoretical screen refresh frequency in a timely manner.

[0103] Alternatively, the pulse period of the first fixed frequency f1 is the first pulse period T1, and the pulse period of the variable frequency f2 is the second pulse period T2, where T2 = n * T1. In other words, n pulse periods of the TE signal correspond to one display data transmission. That is, after n pulse periods of the TE signal, the SOC transmits display data once.

[0104] Take the first fixed frequency f1 = 360 Hz as an example:

[0105] like Figure 6 As shown, the screen refresh frequency of the current frame is f = 120 Hz, so n = f1 / f = 360 / 120 = 3. The variable frequency of the current frame is f2 = f1 / n = 360 / 3 = 120 Hz, which is consistent with the screen refresh frequency f. In other words, the display data is sent once after three pulses of the TE signal.

[0106] The screen refresh rate of the current frame is f = 90 Hz, so n = f1 / f = 360 / 90 = 4. The variable frequency of the current frame is f2 = f1 / n = 360 / 4 = 90 Hz, which is consistent with the screen refresh rate f. In other words, the display data is sent once after four pulses of the TE signal.

[0107] The screen refresh rate of the current frame is f = 60 Hz, so n = f1 / f = 360 / 60 = 6. The variable frequency of the current frame is f2 = f1 / n = 360 / 6 = 60 Hz, which is consistent with the screen refresh rate f. In other words, the display data is sent once after 6 pulses of the TE signal.

[0108] like Figure 5 As shown, the screen refresh frequency of the previous frame is f = 120hz, and the variable frequency f2 of the previous frame is f = 120hz. The screen refresh frequency of the current frame is switched to f = 90hz (for example Figure 5 The position of the middle arrow is the switching moment), the variable frequency f2 of the current frame can also be directly switched to 120 Hz, without waiting until the next frame to switch the variable frequency f2 to 120 Hz.

[0109] After the above-mentioned SOC and DDIC are applied to the electronic device 1 provided in the embodiment of the present application, the DDIC is used to send a TE signal with a first fixed frequency f1 to the SOC, and the SOC is used to receive the TE signal and output display data to the DDIC at a variable frequency f2 according to the TE signal.

[0110] The embodiment of the present application further provides a driving method of an electronic device 1, comprising:

[0111] S1, DDIC sends the TE signal with a first fixed frequency f1.

[0112] For the way DDIC sends TE signals, please refer to the above Figure 3 The description of DDIC in the example is not repeated here.

[0113] S2, SOC receives the TE signal and outputs display data to DDIC at a variable frequency f2 according to the TE signal.

[0114] The way SOC outputs display data to DDIC can refer to the above Figure 3 The description of the SOC in the example will not be repeated here.

[0115] In the electronic device 1 provided in the embodiment of the present application, the frequency of the TE signal transmitted by the DDIC is a high-frequency first fixed frequency f1, which is a common multiple of all screen refresh frequencies f supported by the electronic device 1. Therefore, the first fixed frequency f1 is divisible by each screen refresh frequency f. The possible values ​​of the variable frequency f2 are the same as those of the screen refresh frequency f. Therefore, the first fixed frequency f1 is divisible by each variable frequency f2. That is, f1 / f2 = n. Correspondingly, the second pulse period T2 of the variable frequency f2 is divisible by the first pulse period T1 of the first fixed frequency f1. That is, T2 / T1 = n. In other words, each second pulse period T2 is n times the first pulse period T1. When the screen refresh frequency f of the current frame (i.e., the theoretical screen refresh frequency) is changed, there is no need to delay the screen refresh frequency f of the previous frame. The variable frequency f2 only needs to be changed synchronously by the number n of first pulse periods T1. Therefore, the variable frequency f2 can respond to the change of the screen refresh frequency f in a timely manner, quickly follow the change of the screen refresh frequency f, and change the value of the variable frequency f2 to the screen refresh frequency f, then the actual screen refresh frequency of the electronic device 1 is also the screen refresh frequency f. Based on this, in the embodiment of the present application, when the screen refresh frequency f of the electronic device 1 changes, the actual screen refresh frequency can also respond to the image refresh frequency of the SOC (that is, the theoretical screen refresh frequency) in a timely manner, and realize smooth and infinite (seamless) switching between multiple screen refresh frequencies f. Moreover, since smooth and infinite switching can be achieved in various scenarios, a set of frame cutting drive logic can be adopted, and there is no need to be compatible with the situation where the SOC sends a delayed or non-delayed frequency change, which reduces the complexity of the logic processing, realizes the screen following the image, infinite frame change, and can also avoid logical errors caused by inconsistent drive interaction timing.

[0116] By adopting the above-mentioned driving method provided in the embodiment of the present application, the screen can move with the image and the frame rate can be infinitely changed. The refresh rate of the screen can follow the image processing frequency of the SOC (that is, the theoretical screen refresh frequency) in real time, and there is no need for additional interaction through the instructions of changing the screen refresh rate. The entire driving logic is simple and efficient.

[0117] The electronic device 1 and the driving method thereof provided in the embodiments of the present application are schematically described below using two examples.

[0118] Example 1

[0119] The embodiment of the present application provides a DDI C, such as Figure 5 As shown, DDIC is used to continuously send TE signals, and the frequency of the TE signals sent by DDIC is a first fixed frequency.

[0120] For example, the first fixed frequency f1 is a common multiple of multiple screen refresh frequencies f supported by the electronic device 1. For example, the first fixed frequency f1 is the least common multiple of multiple screen refresh frequencies f supported by the electronic device 1.

[0121] In this example, 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 the first fixed frequency f1 of the TE signal is 360 Hz. The values ​​of n may include 360, 36, 12, 4, and 3.

[0122] The embodiment of the present application further provides a SOC, which is used to receive the above-mentioned TE signal and output display data once after accumulating n pulses of the TE signal.

[0123] by Figure 5 For example, after the first pulse B1 of the TE signal, the SOC sends display data (image data) once. The screen refresh frequency of the current frame is f=120hz. The SOC knows that it can send display data once after accumulating 3 (360 / 120) pulses. So the SOC continues to receive the TE signal, and after accumulating 3 pulses, it sends display data (self-refresh instruction) once after the fourth pulse B4 of the TE signal. After the SOC sends the self-refresh instruction, the screen refresh frequency of the current frame changes, f=90hz. The SOC knows that it can send display data once after accumulating 4 (360 / 90) pulses. So the SOC continues to receive the TE signal, and after accumulating 4 pulses, it sends display data (image data) once after the eighth pulse B8 of the TE signal. Therefore, after the screen refresh frequency f of the current frame changes, the SOC sending cycle follows the change in time, and there will be no delay of one frame change.

[0124] The change of the screen refresh frequency f is controlled by the upper layer instructions of the electronic device 1. Synchronously, the change of the counting threshold value of the SOC for the TE signal pulse is also controlled synchronously by the upper layer instructions.

[0125] In some embodiments, the value of the first fixed frequency f1 is greater than the maximum screen refresh frequency f among the screen refresh frequencies f supported by the electronic device 1. Alternatively, it can be understood that the value of n is greater than 1.

[0126] This can alleviate the problem that the SOC is easily triggered to send display data in an error situation due to the value of n being too small.

[0127] Figure 7 A flowchart of a driving method of an electronic device provided in an embodiment of the present application.

[0128] When the above-mentioned DDIC and SOC are applied to the electronic device 1, the driving method of the electronic device includes:

[0129] S10. DDIC continues to send TE signals.

[0130] S20 , the SOC receives the TE signal, and after accumulating n pulses of the TE signal, outputs one display data to the DDIC.

[0131] The first fixed frequency f1 of the TE signal is 360 Hz. The SOC's image transmission logic triggers the SOC to send image data or send a self-refresh command after receiving n pulses of the specified TE signal. Where n is the ratio of the first fixed frequency f1 to the screen refresh frequency f of the current frame (or the target refresh rate).

[0132] For example, Figure 5 In the example, when the screen refresh frequency is f = 120 Hz, n = 3. The SOC internally counts and triggers the SOC to send display data after receiving three pulses of the TE signal. When the screen refresh frequency is f = 90 Hz, n = 4. The SOC internally counts and triggers the SOC to send display data after receiving four pulses of the TE signal.

[0133] In an embodiment of the present application, the multiple screen refresh rates f supported by the electronic device 1 can be switched randomly according to the application scenario without rules. That is, the screen refresh rate f of the current frame can be switched randomly. For example, the screen refresh rate f of the previous frame is 120 Hz, the screen refresh rate f of the current frame can be any one of 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, and 120 Hz, and the screen refresh rate f of the next frame can also be any one of 1 Hz, 10 Hz, 20 Hz, 60 Hz, 90 Hz, and 120 Hz. It is not limited to that the screen refresh rate f can only be increased, or that the screen refresh rate f can only be reduced.

[0134] In the electronic device 1 provided in the embodiment of the present application, the interaction logic between the DDIC and the SOC is as follows: the DDIC continuously transmits a TE signal with a first fixed frequency f1, while the SOC internally counts n TE signal pulses as a trigger for the SOC to send display data. The DDIC and SOC implement refresh frequency changes directly through the SOC's internal count, eliminating the need for a CMD. This TE signal transmission logic is simple, reducing control complexity.

[0135] Figure 8 This is a waveform diagram of a TE signal and a start-of-light emission control (STV-EM) signal provided in an embodiment of the present application.

[0136] In some embodiments, the DDIC is also used to send STV-EM signals.

[0137] For example, the DDIC is used to send an STV-EM signal to the display screen 10 of the electronic device 1. The gate driving circuit 12 in the display screen 10 can receive the STV-EM signal and provide an EM signal to each row of pixel circuits 111 according to the STV-EM signal.

[0138] For example, Figure 8 As shown, the frequency of the STV-EM signal is the second fixed frequency f3, and the second fixed frequency f3 is an integer multiple of the first fixed frequency f1. Figure 8 In the figure, the second fixed frequency f3 is equal to the first fixed frequency f1 as an example for illustration.

[0139] like Figure 7 As shown, the driving method of the electronic device further includes:

[0140] S30 . The DDIC sends an STV-EM signal to the display screen 10 .

[0141] Of course, before the DDIC sends the STV-EM signal to the display screen 10, the DDIC may also send the STV-SCAN signal, the data voltage Vdata, etc. to the display screen 10. The embodiment of the present application only schematically illustrates some steps in the driving method of the electronic device, and the driving method of the electronic device may also include other steps.

[0142] By setting the second fixed frequency f3 of the STV-EM signal to an integer multiple of the first fixed frequency f1 of the TE signal, the first pulse period T1 of the TE signal is an integer multiple of the pulse period T3 of the STV-EM signal. Therefore, the number of pulses of the STV-EM signal corresponding to each pulse period of the TE signal is fixed, and there will not be a situation where the number of pulses of the STV-EM signal corresponding to each pulse period is different. Therefore, a pulse period of the TE signal can be regarded as a minimum repeating unit with fixed brightness. When switching the screen refresh frequency f, the brightness of the display screen 10 can remain consistent, thereby improving the display effect.

[0143] The electronic device 1 provided in the embodiment of the present application, when changing the screen refresh frequency f, only needs to change the number of pulses of the accumulated TE signal so that the variable frequency f2 can respond to the change of the screen refresh frequency f in a timely manner, quickly follow the change of the screen refresh frequency f, and realize that the actual screen refresh frequency responds to the image refresh frequency of the SOC (that is, the theoretical screen refresh frequency) in a timely manner, and switches smoothly and seamlessly between multiple screen refresh frequencies f. By using the above-mentioned driving method provided in the embodiment of the present application to drive the electronic device, the screen can be driven with the image, and the frame rate can be changed infinitely. The refresh rate of the screen can follow the image processing frequency of the SOC (that is, the theoretical screen refresh frequency) in real time, and no additional interaction is required through the screen refresh rate change instruction. The entire driving logic is simple and efficient.

[0144] Example 2

[0145] Figure 9 and Figure 10 A pulse diagram of another TE signal and display data transmission frequency provided in an embodiment of the present application.

[0146] The embodiment of the present application provides a DDI C, such as Figure 9 As shown, DDIC is used to send TE signals intermittently.

[0147] For example, after DDIC sends n1 pulses of the TE signal, it does not send a TE signal for a period of n2 pulses. The period of the n1 pulses sent is the same as the period of the n2 pulses not sent. In other words, the pulse duration of DDIC's TE signal transmission or suspension of TE signal transmission is calculated using the first fixed frequency f1. The calculation method for the first fixed frequency f1 is the same as in Example 1.

[0148] Here, the DDIC does not send the TE signal. This may be because the DDIC itself does not execute the instruction to send the TE signal, or it may be because the DDIC executes the instruction to send the TE signal but the TE signal within n2 pulse periods is not received by the SOC.

[0149] The embodiment of the present application further provides a SOC, which is used to receive the above-mentioned TE signal and output display data once after accumulating n1 pulses of the TE signal.

[0150] Wherein, n1+n2=n, n2 is a fixed positive integer and is smaller than the minimum value of n.

[0151] The minimum value of n is obtained by dividing the first fixed frequency f1 by each screen refresh rate f supported by the electronic device 1, and the minimum value among the multiple values ​​of n is the minimum value of n in the embodiment of the present application. For example, the values ​​of n may include 360, 36, 12, 4, and 3, so n2 is less than 3. Figure 9 In the figure, n2=2 is taken as an example for illustration.

[0152] n2 is a fixed positive integer. This means that for a particular electronic device 1, once the value of n2 is determined within a range less than the minimum value of n, the value of n2 remains unchanged regardless of how the screen refresh rate f is changed. However, the value of n2 may vary for different electronic devices 1.

[0153] by Figure 9For example, n2=2, after the first pulse C1 of the TE signal, the SOC sends display data (image data) once. The screen refresh frequency of the current frame is f=120hz, and the SOC knows that it can send display data once after accumulating n1=1(3-2) pulses. The SOC continues to receive TE signals, and after the first pulse C1, it does not send TE signals in the subsequent two pulse intervals until it sends TE signals again at the moment corresponding to the fourth pulse C4. The SOC starts accumulating from the fourth pulse C4, and after receiving 1 pulse, it sends display data (self-refresh instruction) once after the fourth pulse C4 of the TE signal. After the SOC sends the self-refresh instruction, the screen refresh frequency of the current frame changes to f=90hz, and the SOC knows that it can send display data once after accumulating n1=2(4-2) pulses. The SOC continues to receive TE signals, and after the fourth pulse C4, it does not send TE signals in the subsequent two pulse intervals until it sends TE signals again at the moment corresponding to the seventh pulse C7. The SOC starts accumulating data from the seventh pulse C7, and after receiving two pulses, it sends the display data (image data) after the eighth pulse B8 of the TE signal. Therefore, when the screen refresh rate f of the current frame changes, the SOC sending cycle follows the change in time, without delaying the change by one frame.

[0154] like Figure 10 As shown, taking the screen refresh frequency f=120 Hz as an example, if the screen refresh frequency f remains unchanged, the SOC will continue to receive 1 pulse cumulatively and send display data once.

[0155] Figure 11 A flowchart of a driving method of an electronic device provided in an embodiment of the present application.

[0156] When the above-mentioned DDIC and SOC are applied to the electronic device 1, the driving method of the electronic device includes:

[0157] S100 , after the DDIC sends n1 pulses of the TE signal, it does not send the TE signal within n2 pulse periods.

[0158] S200, SOC is used to receive the above TE signal and output display data once after accumulating n1 pulses of the TE signal.

[0159] The first fixed frequency f1 of the TE signal is 360 Hz. The SOC's image transmission logic triggers the SOC to send image data or send a self-refresh command after receiving n-n2 pulses of the specified TE signal. Where n is the ratio of the first fixed frequency f1 to the screen refresh frequency f of the current frame (or the target refresh rate), and n2 is a fixed positive integer that is the smallest value less than n.

[0160] For example, Figure 9In the example, when the screen refresh frequency is f = 120 Hz, n = 3, n2 = 2, and n = 1. The SOC internally counts and triggers the SOC to send display data after receiving one pulse of the TE signal. However, DDIC does not send a TE signal during the screen refresh process. When the screen refresh frequency is f = 90 Hz, n = 4, n2 = 2, and n = 2. The SOC internally counts and triggers the SOC to send display data after receiving two pulses of the TE signal.

[0161] In the electronic device 1 provided by the embodiment of the present application, the interaction logic between the DDIC and the SOC is as follows: the DDIC continuously and intermittently sends a TE signal at a first fixed frequency f1, and the SOC internally counts n1 pulses of the TE signal as a condition for triggering the SOC to send display data.

[0162] Figure 12 This is a waveform diagram of a TE signal and a start-of-light emission control (STV-EM) signal provided in an embodiment of the present application.

[0163] In some embodiments, DDIC is also used to send STV-EM signals.

[0164] like Figure 11 As shown, the driving method of the electronic device further includes:

[0165] S300 , DDIC sends an STV-EM signal to the display screen 10 .

[0166] The electronic device 1 provided by the embodiment of the present application, when changing the screen refresh frequency f, as long as the pulse number of the accumulated TE signal is changed immediately, the variable frequency f2 can respond to the change of the screen refresh frequency f in a timely manner, quickly follow the change of the screen refresh frequency f, and realize that the actual screen refresh frequency responds to the image refresh frequency of the SOC (that is, the theoretical screen refresh frequency) in a timely manner, and the multiple screen refresh frequencies f are switched smoothly and seamlessly. Moreover, the DDIC sends the TE signal intermittently. After triggering the SOC to send display data, it no longer sends the TE signal to the SOC, and the SOC also pauses counting until the next time it receives the TE signal, and the counting restarts. This can reduce the probability of the SOC sending the display data frequency (variable frequency f2) and the current frame screen refresh frequency f conflicting due to counting errors. It can reduce and reduce the requirements for the stability of the SOC system, while eliminating the conflict between the variable frequency f2 and the current frame screen refresh frequency f caused by occasional stability problems, thereby eliminating the problem of abnormal display. By using the above-mentioned driving method provided in the embodiment of the present application to drive an electronic device, the screen can move with the image and the frame rate can be infinitely changed. The refresh rate of the screen can follow the image processing frequency of the SOC (that is, the theoretical screen refresh frequency) in real time, and there is no need for additional interaction through instructions for changing the screen refresh rate. The entire driving logic is simple and efficient.

[0167] The computer program corresponding to the driving method of the electronic device provided in the embodiment of the present application may be stored in the hardware abstraction layer (HAL) of the electronic device 1 , or may be stored in the kernel of the electronic device 1 .

[0168] The present application also provides a computer-readable medium storing a computer program. When executed by a processor, the computer program implements the aforementioned method for driving an electronic device. The present application also provides a computer program product containing instructions. When the computer program product is executed on an electronic device, the electronic device executes the aforementioned method for driving an electronic device.

[0169] The computer-readable medium may be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a random access memory (RAM) or other type of dynamic storage device that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory may exist independently and be connected to the processor via a communication bus. The memory may also be integrated with the processor.

[0170] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented using a software program, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer-executable instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another computer-readable storage medium.

[0171] The above is only a specific embodiment of the present application, but the scope of protection of this application is not limited to this. Any changes or substitutions within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. An electronic device, characterized in that: Includes display driver and processor; The display driver is used to send a tearing effect TE signal; the frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of multiple screen refresh frequencies supported by the electronic device; The processor is used to receive the TE signal and output display data to the display driver at a variable frequency; Wherein, f1=n*f2, f1 is the first fixed frequency, f2 is the variable frequency of the current frame; n is the ratio of the first fixed frequency to the screen refresh frequency of the current frame, and n changes with the change of the screen refresh frequency; The display driver is configured to send n1 pulses of the TE signal and then not send the TE signal within n2 pulse periods; The processor is configured to output the display data to the display driver once after accumulating n1 pulses of the TE signal; Wherein, n1+n2=n, n2 is a fixed positive integer and is smaller than the minimum value of n.

2. The electronic device according to claim 1, wherein The screen refresh frequency of the current frame may be switched irregularly.

3. The electronic device according to claim 1 or 2, characterized in that: The electronic device further includes a display screen; The display driver is further configured to send a light emission control start STV-EM signal to the display screen, wherein the 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.

4. A method for driving an electronic device, characterized in that: The electronic device includes a display driver and a processor; The driving method includes: The display driver sends a tearing effect TE signal; the frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of multiple screen refresh frequencies supported by the electronic device; The processor receives the TE signal and outputs display data to the display driver at a variable frequency; Wherein, f1=n*f2, f1 is the first fixed frequency, f2 is the variable frequency of the current frame; n is the ratio of the first fixed frequency to the screen refresh frequency of the current frame, and n changes with the change of the screen refresh frequency; After the display driver sends n1 pulses of the TE signal, it does not send the TE signal within n2 pulse periods; After the processor has received n1 pulses of the TE signal cumulatively, it outputs the display data to the display driver once; Wherein, n1+n2=n, n2 is a fixed positive integer and is smaller than the minimum value of n.

5. The driving method according to claim 4, wherein: The screen refresh frequency of the current frame may be switched irregularly.

6. The driving method according to claim 4 or 5, characterized in that: The electronic device further includes a display screen; The driving method includes: The display driver sends a light emission control start STV-EM signal to the display screen, where the frequency of the STV-EM signal is a second fixed frequency, which is an integer multiple of the first fixed frequency.

7. A display driver, characterized in that: Used in electronic equipment; The display driver is configured to send a tearing effect TE signal; the frequency of the TE signal is a first fixed frequency, which is a common multiple of multiple screen refresh frequencies supported by the electronic device; The display driver is further configured to receive display data at a variable frequency; Wherein, f1=n*f2, f1 is the first fixed frequency, f2 is the variable frequency of the current frame; n is the ratio of the first fixed frequency to the screen refresh frequency of the current frame, and n changes with the change of the screen refresh frequency; The display driver is configured to send n1 pulses of the TE signal and then not send the TE signal within n2 pulse periods; Wherein, n2 is a fixed integer, and n1 changes with the screen refresh frequency.

8. The display driver according to claim 7, wherein: The display driver is further configured to send a light emission control start signal STV-EM, wherein the 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.

9. A processor, characterized in that: Used in electronic equipment; The processor is used to receive a tearing effect TE signal; the frequency of the TE signal is a first fixed frequency, and the first fixed frequency is a common multiple of multiple screen refresh frequencies supported by the electronic device; The processor is further configured to output display data at a variable frequency; Wherein, f1=n*f2, f1 is the first fixed frequency, f2 is the variable frequency of the current frame; n is the ratio of the first fixed frequency to the screen refresh frequency of the current frame, and n changes with the change of the screen refresh frequency; The processor is configured to output the display data once after receiving n1 pulses of the TE signal cumulatively; Among them, n-n1 is a fixed positive integer.

10. A computer-readable medium, characterized in that The computer-readable medium stores a computer program, and when the computer program is executed on an electronic device, the electronic device executes the driving method according to any one of claims 4 to 6.

Citation Information

Patent Citations

  • Display screen frequency conversion method, display driving integrated circuit chip and application processor

    CN115019732A

  • Display frame rate adjusting method and device, application processor and electronic equipment

    CN115100993A

Cited By

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

    EP4723093A1

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

    WO2025016193A1