Drive signal output device, drive signal output method, and display device

Abstract

This embodiment relates to a touch sensing device for sensing a touch by a touch electrode arranged in a display panel. A touch drive circuit is provided which is configured to output a display drive signal in a display period within a data write period in a low drive mode in which there is a data hold period between data write periods, and to output a touch drive signal in a touch sensing period within the data write period.

Description

Technical Field

[0001] This embodiment relates to a drive signal output device, a drive signal output method, and a display device including a drive signal output circuit. Background Technology

[0002] With the development of information technology, various display devices capable of visualizing information are being developed. Liquid crystal displays (LCDs), organic light-emitting diode (OLED) displays, and plasma display panel (PDP) displays have been developed or are under development. These display devices are evolving to appropriately display high-resolution images.

[0003] Display panels in various electronic devices (e.g., televisions (TVs), laptops, mobile devices, etc.) often incorporate extensive touch functionality. In such cases, the display panel is implemented as a flat panel display. Touch functionality can be implemented as a touch panel combined with the display panel. A touch panel refers to a panel that allows a user to operate the device or execute a program by pressing text, images, icons, etc.

[0004] Touch panels can be configured to perform touch recognition, for example, capacitively. As an example of a touch panel implementing capacitive touch recognition, a "mutual capacitance touch sensing device" has been proposed. The touch pattern, as an example, has a configuration independent of the display panel. The touch panel can be manufactured separately and combined with the display panel. The configuration of combining the touch panel and the display panel, as described above, leads to various difficulties such as process complexity and increases manufacturing costs.

[0005] To address this issue, efforts are underway to develop devices in which display components and touch recognition components are shared. A representative example is the in-cell method. The in-cell method refers to implementing touch recognition through configurations that enable touch functionality within pixels of the display panel. Various in-cell methods have been developed. Pixels implemented using the in-cell method can have both display and touch recognition capabilities implemented in parallel. For example, in a device that provides both touch and display functionality (hereinafter referred to as a "display device"), touch and display operations can be performed in a time-division manner using display drive signals and touch drive signals.

[0006] According to an implementation, the display device can operate in a low-speed drive mode (e.g., a low refresh rate (LRR) mode) where the display refresh rate is reduced to decrease power consumption when the display remains unchanged. In the low-speed drive mode, the display device can be configured to perform only a minimum number of touch sensing operations per display frame (e.g., one touch sensing) to reduce power consumption. Therefore, touch operations in the low-speed drive mode may be delayed.

[0007] Therefore, a method is needed to reduce the latency of touch operations in low-speed driving mode. Summary of the Invention

[0008] Technical issues

[0009] Against this background, one objective of this embodiment is to provide a drive signal output device, a drive signal output method, and a display device that can reduce the delay of touch operation by recognizing the presence or absence of touch and the touch position within a data writing interval when the display device is operating in a low-speed drive mode.

[0010] Technical solution

[0011] To achieve the above objectives, the drive signal output device according to the embodiment includes: a display drive circuit configured to output a display drive signal in a display interval within a first data write interval in a low-speed drive mode where the data holding interval is located between data write intervals; and a touch drive circuit configured to identify a first touch detected in a first touch sensing interval within the first data write interval, and to identify the position of the first touch in a second touch sensing interval within the first data write interval.

[0012] According to another embodiment, the drive signal output method includes: operating in a low-speed drive mode where the data holding interval is between data writing intervals; in the low-speed drive mode, outputting a display drive signal in a display interval within a first data writing interval; identifying a first touch detected in a first touch sensing interval within the first data writing interval; and identifying the position of the first touch in a second touch sensing interval within the first data writing interval in response to identifying the first touch detected.

[0013] A display device according to another embodiment includes: a panel; a display driving circuit configured to output a display driving signal in a display interval within a first data writing interval in a low-speed driving mode where the data holding interval is between data writing intervals; and a touch driving circuit configured to identify a first touch detected in a first touch sensing interval within the first data writing interval, and to identify the position of the first touch in a second touch sensing interval within the first data writing interval.

[0014] Beneficial effects

[0015] As described above, according to this embodiment, when the display device operates in low-speed drive mode, the delay of touch operation can be reduced by recognizing the presence or absence of touch and the touch position within a data writing interval.

[0016] For example, according to this embodiment, when the display device operates from touch idle mode to LRR mode, it can report the position of the touch within the same idle frame when a touch is detected. Therefore, the display frame rate can be increased immediately. Attached Figure Description

[0017] Figure 1 This is a block diagram of a display device according to an embodiment.

[0018] Figure 2 This is a timing diagram illustrating a method for driving a display device according to an embodiment.

[0019] Figure 3 This is a detailed configuration diagram of the display device according to the embodiment.

[0020] Figure 4 This is a diagram illustrating the normal mode operation of the display device according to an embodiment.

[0021] Figure 5 This is a diagram illustrating the operation of the display device according to an embodiment in low-speed drive mode.

[0022] Figure 6 This is a diagram illustrating the synchronization signal for the defined display interval and touch sensing interval according to an embodiment.

[0023] Figure 7 This is a diagram illustrating touch sensing operation in a low-speed driving mode according to an embodiment.

[0024] Figure 8 This is a diagram illustrating the detection of touch in low-speed driving mode according to an embodiment.

[0025] Figure 9 This is a diagram illustrating touch sensing operation in a low-speed driving mode according to an embodiment.

[0026] Figure 10 This is a diagram illustrating the detection of touch in low-speed driving mode according to an embodiment.

[0027] Figure 11 This is a flowchart illustrating a touch sensing method according to an embodiment. Detailed Implementation

[0028] The touch display device according to an embodiment of the present invention can perform display and touch sensing (or touch recognition) in a time-division manner, and may include a configuration in which the display components and the touch recognition components are shared in a built-in embedded manner. However, this embodiment is not limited to the time-division method or the embedded method. For example, the touch display device of the embodiment described below can be implemented using an external method and an on-cell method, which are both external and built-in methods.

[0029] According to various implementations, display and touch recognition of a touch display device can be implemented as separate operations. Here, display means expressing a target image by driving the pixels of the display panel. Touch recognition means recognizing the touch position on the display panel. The time-division method means performing display and touch recognition alternately in each time domain.

[0030] More specifically, the time-division method can be implemented such that display and touch recognition are performed alternately on a frame-by-frame basis, which constitutes the image. That is, display and touch recognition can be performed sequentially and alternately, corresponding to multiple frames constituting the image. Furthermore, in the time-division method, touch recognition can be performed two or more times within each frame constituting the image.

[0031] The embedded method is implemented to enable simultaneous display and touch recognition on pixels in the display panel. For this purpose, a common component capable of providing capacitance for touch recognition can be used. At least a connection point of said component may be included. An example of a connection point could be a node (COM) for applying a common voltage, but is not limited to this, and various components may be used as connection points depending on the manufacturer's intent.

[0032] Figure 1 This is a configuration diagram of a display device including a touch sensing device according to an embodiment of the present invention. Figure 1 As shown, the display device 100 according to an embodiment of the present invention performs display functions and touch sensing functions. The display device 100 according to an embodiment of the present invention can be implemented as a flat panel display such as a liquid crystal display (LCD) or an organic light-emitting diode (OLED) display. In the embodiments described below, an LCD is used as an example, but the invention is not limited thereto. That is, the same or similar content can be applied to LED- or OLED-based displays.

[0033] In one embodiment, the display device 100 according to the present invention may include a capacitive touchscreen. The touchscreen may be integrated within the display device 100 to sense touches caused by contact with conductive objects such as fingers or active pens. This touchscreen may be configured independently of the display panel used to implement the display, or it may be embedded in the pixel array of the display panel.

[0034] like Figure 1 As shown, the display device 100 according to an embodiment of the present invention may include a panel driving device 110, a panel 120 (e.g., a display panel or a touch panel), and a touch sensing unit 140 (e.g., a touch sensing device, a touch driving circuit, a touch sensing circuit, a touch controller, or a touch microcontroller unit (MCU)).

[0035] Panel 120 displays an image at a predetermined grayscale level or receives touch input from a hand (or finger) or an active pen (or electronic pen). Panel 120 may be a display panel with an embedded touch structure employing a capacitive method. In one embodiment, panel 120 may be an embedded touch display panel employing a self-capacitance method or an embedded touch display panel employing a mutual capacitance method. Hereinafter, for ease of description, it will be assumed that panel 120 is a self-capacitance embedded touch display panel.

[0036] Panel 120 can operate in display mode and touch sensing mode. Panel 120 can display an image during display mode and be used as a touch panel for touch sensing during touch sensing mode.

[0037] The panel driving device 110 may include a data driving circuit 112 (e.g., a data driving circuit, a source driver circuit, a source driver integrated circuit (SDIC), a display driving circuit, etc.), a gate driving circuit 114, and a timing controller 116 (e.g., a controller, a control unit, and a T-CON). Each of the data driving circuit 112, the gate driving circuit 114, and the touch sensing unit 140 may drive at least one element included in the panel 120.

[0038] The data driving circuit 112 can drive the data lines DL (e.g., D1 to Dn) connected to the pixel P. The gate driving circuit 114 can drive the gate lines GL (e.g., G1 to Gm) connected to the pixel P. The touch sensing unit 140 can drive the electrodes (EL) or touch electrodes (TE) disposed on the panel 120.

[0039] The data driving circuit 112 can supply data voltage to the data line DL to display an image on each pixel P of the panel 120. The data driving circuit 112 may include at least one data driver integrated circuit. The at least one data driver integrated circuit can be connected to bonding pads of the panel 120 using a tape auto-bonding (TAB) method or a chip-on-glass (COG) method, or it can be directly formed on the panel 120. In some cases, at least one data driver integrated circuit can be integrated into the panel 120. Furthermore, the data driving circuit 112 can be implemented using a chip-on-film (COF) method.

[0040] The gate driving circuit 114 can supply a scan signal to the gate line GL to turn on / off a switch (e.g., a transistor) located in each pixel P. Depending on the driving method, the gate driving circuit 114 can be configured as follows: Figure 1The gate drive circuit 114 may be located only on one side of panel 120, or it may be divided into two and located on both sides of panel 120. Furthermore, the gate drive circuit 114 may include at least one gate driver integrated circuit. The at least one gate driver integrated circuit may be connected to bonding pads of panel 120 using a tape-on-board (TAB) method or a chip-on-glass (COG) method, or it may be directly formed on panel 120 using a gate-in-panel (GIP) method. In some cases, the at least one gate driver integrated circuit may be integrated on panel 120. Furthermore, the gate drive circuit 114 may be implemented using a chip-on-film (COF) method.

[0041] Panel 120 may include only a touch screen panel (TSP), and may further include a display panel. Here, the touch panel and the display panel may share some components. For example, the touch electrode TE in the touch panel for sensing touch may be used as a common voltage electrode in the display panel that is supplied with a common voltage.

[0042] In cases where some components of the display panel and touch panel are shared, this panel 120 is sometimes referred to as an integrated panel, but the present invention is not limited thereto. Additionally, it is known that an embedded panel is a form in which the display panel and touch panel are integrated and connected. However, this is merely an example of the panel 120 described above, and the panels to which the present invention applies are not limited to this type of embedded panel.

[0043] Furthermore, multiple touch electrodes TE can be provided on panel 120, and touch sensing unit 140 can drive touch electrodes TE using a drive signal. Touch sensing unit 140 can generate a sensing value of touch electrodes TE based on a response signal formed on touch electrodes TE in response to the drive signal. Touch sensing unit 140 can calculate touch coordinates using the sensing values ​​of the multiple touch electrodes TE provided on panel 120. The calculated touch coordinates can be sent to another device (e.g., a host, controller, or processor) and used by that device.

[0044] According to one embodiment, pixel P may include a transistor (e.g., a TFT), a liquid crystal LC, and a common voltage electrode VCOM. The gate terminal of the transistor TFT may be connected to the gate line GL, the drain terminal may be connected to the data line DL, and the source terminal may be connected to the liquid crystal LC.

[0045] A scan signal SCAN, corresponding to the turn-on voltage, can be supplied to the gate terminal via the gate line GL. In this case, the drain and source terminals of the transistor TFT can be turned on, and the data voltage Vdata can be supplied to the liquid crystal LC. A common voltage can be supplied to the common voltage electrode VCOM. Based on the difference between the common voltage and the data voltage Vdata, the brightness of pixel P can be adjusted while controlling the liquid crystal LC.

[0046] Furthermore, the common voltage electrode VCOM can be the same as that referenced. Figure 1 The described touch sensing unit (see Figure 1 The electrode driven by the touch electrode TE in 140) is the same electrode. This has been described as an example, but embodiments of the invention are not limited thereto.

[0047] According to an embodiment, the touch sensing unit 140 can drive the touch electrode TE using a drive signal Stx. The touch sensing unit 140 can sense the touch or proximity of an external object OBJ to the panel based on the response signal Srx formed on the touch electrode TE in response to the drive signal Stx.

[0048] In this case, the touch sensing unit 140 can employ a capacitive touch method. In the capacitive touch method, the approach or touch of the object OBJ is identified by detecting the capacitance or capacitance change of the touch electrode TE.

[0049] This capacitive touch method can be categorized into, for example, mutual capacitance touch methods and self-capacitance touch methods. In the mutual capacitance touch method, a type of capacitive touch method, a drive signal Stx is applied to one touch electrode, and another touch electrode interconnected with one touch electrode is sensed. In this mutual capacitance touch method, the value sensed by the other touch electrode can change based on the touch or proximity of an object OBJ, such as a finger or pen. In the mutual capacitance touch method, the presence or absence of a touch, touch coordinates, etc., can be detected using the sensed values.

[0050] In self-capacitance touch, another type of capacitive touch method, a drive signal Stx is applied to a touch electrode, and then the corresponding touch electrode is sensed again. In this self-capacitance touch method, the value sensed by the corresponding touch electrode can change according to the touch or proximity of an object OBJ such as a finger or pen. In self-capacitance touch, the presence or absence of a touch, touch coordinates, etc., can be detected using the sensed values.

[0051] In this self-capacitance touch method, the touch electrode used to apply the driving signal Stx and the touch electrode used for sensing can be the same. This embodiment can be applied to both mutual capacitance touch methods and self-capacitance touch methods. In some examples below, for ease of explanation, the case where this embodiment is applied to a self-capacitance touch method will be described.

[0052] According to the implementation, the timing controller 116 can provide display control signals to the data driving circuit 112 and the gate driving circuit 114, and provide touch control signals to the touch sensing unit 140, so that display and touch recognition can be performed in a time-division manner.

[0053] The timing controller 116 can output display control signals, which may include source control signals, gate control signals, clock pulses, horizontal synchronization signals or vertical synchronization signals, and switching signals SW.

[0054] The data driving circuit 112 can be configured to receive a source control signal included in the display control signal, generate a source drive signal corresponding to the source control signal, and provide the generated source drive signal to the pixels of the panel 120. The data driving circuit 112 typically includes a latch, a digital-to-analog converter (DAC), and an output buffer. Here, the latch can store data according to the source control signal and then provide the data to the DAC. The DAC can output an analog signal of the voltage corresponding to the data. The output buffer can transmit the output of the DAC as a source drive signal to the pixels of the panel 120 via the source line SL.

[0055] The gate driving circuit 114 can receive the gate control signal included in the display control signal, generate a gate driving signal corresponding to the gate control signal, and provide the generated gate driving signal to the pixels of the panel 120. According to an embodiment, the gate driving circuit 114 may include an input buffer, a shift register, a level shifter, and an output buffer.

[0056] The input buffer receives the gate control signal and outputs it to the shift register. The shift register controls the generation of scan pulses (i.e., the gate control signal transmitted through the input buffer) sequentially in columns of panel 120. The level shifter changes the output voltage level of the shift register to a level that enables the thin-film transistor (TFT) composed of switches M to be turned on / off. The output buffer modifies the signal output from the level shifter and outputs the modified signal as a gate drive signal to drive the gate line GL with an RC load.

[0057] Figure 2 This is a timing diagram illustrating a method for driving a display device according to an embodiment. (See reference...) Figure 2 It can be done through, for example Figure 2 The display and touch recognition are sequentially and alternately assigned to a continuous time domain to drive the above in a time-division manner. Figure 1 The implementation method.

[0058] According to an embodiment, the timing controller 116 can provide source control signals and gate control signals to the data driving circuit 112 and the gate driving circuit 114, respectively, for display. The timing controller 116 can control the output of the inactive touch driving signal TDS by providing touch control signals to the touch sensing unit 140 within a time domain set as the display interval. Figure 2In this context, time point T1 is the time point when the device transitions from the display state to the touch recognition state, and time point T2 can be the time point when the device transitions from the touch recognition state to the display state.

[0059] According to the implementation, the timing controller 116 can perform touch recognition control after a time set for the displayed image has elapsed. The timing controller 116 can activate the output of the touch drive signal TDS to perform touch recognition by providing a touch control signal to the touch sensing unit 140. Under the control of the timing controller 116, a touch drive signal TDS as a constant voltage can be applied to each pixel node.

[0060] In the above configuration, the timing controller 116 can switch the switch to a floating state at time T11, which is a predetermined time earlier than the time T1 at which the switch is set to transition from the display state to the touch recognition state. Alternatively, the timing controller 116 can switch the switch to a floating state at time T12, which is a predetermined time later than the time T1 at which the switch is set to transition from the display state to the touch recognition state.

[0061] Figure 3 This is a detailed configuration diagram of the display device according to an embodiment. (Refer to...) Figure 3 The touch display device may include a touch control circuit 310 (touch microcontroller unit (MCU)), a power management circuit 320 (power management IC; PMIC), a touch driver circuit 330 (touch modulation IC; TMIC), a drive signal output circuit 340 (e.g., source driver and touch readout IC (SRIC)), and a panel 350. Figure 3 The display device shown is merely an example, and the embodiments described below are not limited to this. Figure 3 Detailed configuration.

[0062] According to an embodiment, the touch control circuit 310 can provide a synchronization signal to the power management circuit 320, the touch driving circuit 330, and the drive signal output circuit 340. This synchronization signal may include a synchronization signal for distinguishing between display intervals and touch sensing intervals. This synchronization signal may be referred to as a display synchronization signal or a touch synchronization signal. The touch control circuit 310 can be configured to include... Figure 1 At least some of the functions of the timer controller 116 shown, or the timer controller 116 can be replaced.

[0063] According to one embodiment, the power management circuit 320 can receive a synchronization signal (e.g., a touch synchronization signal) from the touch control circuit 310 and output a display drive signal (display VCOM) based on the received synchronization signal. For example, the display drive signal may have a voltage of -1V.

[0064] According to an embodiment, the touch driving circuit 330 may include a touch driving signal generator 331 and a first multiplexer 332. The touch driving circuit 330 may receive a synchronization signal from the touch control circuit 310 and generate a touch driving signal (touch VCOM) based on the received synchronization signal.

[0065] For example, the touch drive signal generator 331 can generate a touch drive signal based on a synchronization signal (e.g., a touch synchronization signal) received from the touch control circuit 310. According to one embodiment, the touch drive signal can be configured as a pulse with a voltage range of 1V to 4V. The first multiplexer 332 of the touch drive circuit 330 can receive the touch drive signal output from the touch drive signal generator 331 and the display drive signal output from the power management circuit 320, and selectively output the touch drive signal and the display drive signal.

[0066] For example, the first multiplexer 332 can selectively output one of the input display drive signal and touch drive signal based on the synchronization signal provided from the touch control circuit 310.

[0067] For example, the first multiplexer 332 can output a display drive signal during a display operation interval in which an image is displayed on the panel 350. The first multiplexer 332 can also output a touch drive signal during a touch sensing operation interval in which a touch is sensed from the panel 350.

[0068] The display drive signal or touch drive signal output from the first multiplexer 332 of the touch drive circuit 330 can be transmitted to the drive signal output circuit 340. The touch drive circuit 330 can be configured to include Figure 1 At least some of the functions of the touch sensing unit 140 shown may be replaced by the touch sensing unit 140.

[0069] According to an embodiment, the drive signal output circuit 340 may include a touch analog front end (AFE) 341, a high voltage (HV) level shifter 342, and a second multiplexer 343.

[0070] According to the implementation, the HV level shifter 342 of the drive signal output circuit 340 can receive a synchronization signal from the touch control circuit 310 and supply a VDD signal to the second multiplexer 343 based on the received synchronization signal.

[0071] For example, since the signal input to the second multiplexer 343 includes a display drive signal in the first voltage range and a touch drive signal in the second voltage range, the HV level shifter 342 can supply an HV level signal (HVDD) (e.g., 17V) to the second multiplexer 343.

[0072] The second multiplexer 343 of the drive signal output circuit 340 can selectively output a display drive signal in a first voltage range or a touch drive signal in a second voltage range based on the HV level signal HVDD supplied from the HV level shifter 342.

[0073] Furthermore, the second multiplexer 343 may include a channel multiplexer and selectively output a drive signal for each channel corresponding to each pixel of the panel 350. In the description of the embodiments described below, the function of the second multiplexer 343 selectively outputting a drive signal for each channel will be omitted.

[0074] For example, the second multiplexer 343 can output a display drive signal to the panel 350 during a display operation interval in which an image is displayed on the panel 350. The second multiplexer 343 can also output a touch drive signal to the panel 350 during a touch sensing operation interval in which a touch is sensed from the panel 350.

[0075] According to an embodiment, during a touch sensing operation interval, the second multiplexer 343 can receive a signal sensed from the panel 350 and supply that signal to the touch AFE 341. The touch AFE 341 can determine whether a touch has occurred based on the signal sensed from the panel 350. Since the method for determining whether a touch has occurred by the touch AFE 341 can use well-known techniques, a detailed description will be omitted.

[0076] Figure 4 This is a diagram illustrating the normal mode operation of the display device according to an embodiment, and Figure 5 This is a diagram illustrating the operation of the display device according to an embodiment in low-speed drive mode.

[0077] According to the implementation method, Figure 1 The timing controller 116 can determine the basic drive mode or the low-speed drive mode based on the mode control signal MOD received from the host system. When the mode control signal MOD is input at a first logic level, the timing controller 116 can determine the mode as the low-speed drive mode. When the mode control signal MOD is input at a second logic level, the timing controller 116 can determine the mode as the basic drive mode. Here, the first logic level can be high, and the second logic level can be low, or vice versa.

[0078] According to the implementation method, a basic driving mode and a low-speed driving mode can be determined based on the display frame rate. The low-speed driving mode reduces the driving frequency used to operate the display device when the input image does not change a preset frame rate (e.g., when a still image is input over a specific or longer time period), thereby controlling the pixel data write cycle to be relatively long. Therefore, power consumption can be reduced.

[0079] Compared to the basic drive mode, the refresh rate at which pixel data in panel 120 is updated may be relatively slower in low-speed drive mode. For example, when the drive frequency in basic drive mode is 60Hz, the drive frequency in low-speed drive mode may be relatively slower than that in basic drive mode, such as 30Hz, 20Hz, ..., 1Hz. Low-speed drive mode is not limited to the timing or conditions of the input still image.

[0080] For example, when the display device operates in standby mode, or when no user command or image is input to the data drive circuit 112 for a predetermined period of time or longer, the display device can operate in low-speed drive mode. In the following description, as an example of the basic drive mode, a display refresh rate of 60Hz will be used. For example, as an example of the low-speed drive mode, a display refresh rate of 20Hz will be used. The basic drive mode can also be referred to as the normal mode. The low-speed drive mode can also be referred to as the low refresh rate (LRR) mode.

[0081] According to the implementation method, refer to Figure 4 In the basic drive mode (e.g., normal mode 410), the display frame may consist only of a data write frame (WR). Each of the first segment 411, the second segment 412, the third segment 413, and the fourth segment 414 may correspond to a display frame.

[0082] For example, the first segment 411 can be called the first data write interval, and the second segment 412 can be called the second data write interval. The third segment 413 can be called the third data write interval, and the fourth segment 414 can be called the fourth data write interval. Assuming that the length of each interval 411, 412, 413, and 414 is 16.6ms, the display refresh rate can be approximately 60Hz (1000 / 16.6).

[0083] In each of the intervals 411, 412, 413, and 414, the display interval Td indicated by "D" and the touch sensing interval Tt indicated by "T" can be alternately repeated. In the display interval Td within each of the data writing intervals 411, 412, 413, and 414, the data driving circuit 112 can be configured to output a display driving signal to the panel 120. In the touch sensing interval Tt within each of the data writing intervals 411, 412, 413, and 414, the touch sensing unit 140 can detect touch sensing to identify whether a touch is present or to identify the touch location (e.g., touch coordinates).

[0084] As described above, in the basic drive mode (e.g., normal mode 410), the display frame may consist only of data write frames (WR). On the other hand, refer to Figure 5In low-speed drive mode (e.g., LRR mode 510), in addition to the data write frame (WF), the display frame may also include a data hold frame (HF).

[0085] The data hold frame (HF) serves only to hold the pixel data written in the data write frame (WF). Within the data hold frame (HF), it is possible to prevent new pixel data from being written to the display panel 120. (See reference...) Figure 5 The first segment 511, the second segment 512, and the third segment 513 can correspond to one display frame. Subsequently, two consecutive intervals, including the fourth segment 514, can correspond to another display frame. According to an embodiment, the first segment 511 and the fourth segment 514 can be referred to as data write intervals, respectively.

[0086] For example, the first segment 511 can be referred to as the first data write interval, and the fourth segment 514 can be referred to as the second data write interval. According to an implementation, the data hold interval of the second segment 512 and the third segment 513 can be located between the first segment 511 (i.e., the first data write interval) and the fourth segment 514 (i.e., the second data write interval). The data hold interval can be referred to as a dummy segment. Assuming the first segment 511 is 16.6 ms and the second segment 512 and the third segment 513 are 33.4 ms, then a display frame can be 50 ms.

[0087] Thus, assuming a display frame length of 50ms, the display refresh rate can be 20Hz (1000 / 50). In the first segment 511 and the fourth segment 514, the display interval Td indicated by "D" and the touch sensing interval Tt indicated by "T" can be alternately repeated. In the display interval Td of each of the data writing intervals 511 and 514, the data driving circuit 112 can be configured to output a display driving signal to the panel 120. In the touch sensing interval Tt of each of the data writing intervals 511 and 514, the touch sensing unit 140 can detect touch sensing to identify whether a touch is present or to identify the touch location (e.g., touch coordinates).

[0088] According to the implementation method, the greater the number or length of data retention frames 512 and 513 between adjacent data writing frames 511 and 514, the slower the display frame rate may be.

[0089] For example, suppose the basic drive mode is 60Hz. In this case, a low-speed drive mode with one data hold frame (HF) between adjacent data write frames (WF) could be 30Hz. A low-speed drive mode with two data hold frames (HF) between adjacent data write frames (WF) could be 20Hz. A low-speed drive mode with 59 data hold frames (HF) between adjacent data write frames (WF) could be 1Hz. For example, the display refresh rate of a low-speed drive mode (e.g., LRR mode 510) can be determined based on the width of the data hold frames or data hold intervals.

[0090] Figure 6 It is a diagram of the synchronization signal for the defined display interval and touch sensing interval according to the implementation method.

[0091] Reference Figure 6 According to the embodiment, the display device can perform display driving to display a screen during a predetermined display driving period (or display interval) D1, D2, ..., D16. According to the embodiment, the display device can perform touch driving to sense touch input from a finger or stylus during a predetermined touch driving period (or touch sensing interval) (T1, T2, ..., T16).

[0092] According to the implementation, the display interval and the touch sensing interval can be time periods that are the same or overlap, or they can be time periods that are separate. When the display interval and the touch sensing interval are the same in time, the display driver and the touch driver can be executed simultaneously. On the other hand, when the display interval and the touch sensing interval are time periods that are separate in time, the display interval and the touch sensing interval can alternate.

[0093] According to an implementation, when the display interval and the touch sensing interval are temporally separated while alternating, the touch sensing interval may correspond to a blank period during which display driving is not performed. The display device may generate a touch synchronization signal Tsync that oscillates between high and low levels, and identify or control the display interval and the touch sensing interval based on the touch synchronization signal Tsync. For example, the touch synchronization signal Tsync may be a drive timing control signal that defines the touch sensing interval.

[0094] For example, the high-level interval (or low-level interval) of the touch synchronization signal Tsync can correspond to the display interval. The low-level interval (or high-level interval) of the touch synchronization signal Tsync can correspond to the touch sensing interval.

[0095] As an example, the method for allocating display intervals and touch sensing intervals within a display frame period can be as follows. That is, a display frame period can be divided into a display interval and a touch sensing interval. Display driving can be performed during a display interval, and touch driving for sensing touch input by fingers and styluses can be performed during a touch sensing interval corresponding to a blank period.

[0096] For example, such as Figure 6 As shown, a display frame period 600 can be divided into two or more display intervals and two or more touch sensing intervals. Display driving can be performed in the two or more display intervals within a display frame period, and touch driving for sensing at least one or two touches by a finger or stylus on the entire screen area or some areas can be performed during the two or more touch sensing intervals.

[0097] Thus, when display driving and touch driving are performed by dividing a display frame period 600 into two or more display intervals and two or more touch sensing intervals, each of the two or more blank periods corresponding to the two or more touch sensing intervals within a display frame period 600 can be referred to as a "long horizontal blank (LHB) interval". For example, two or more periods of performing touch sensing for a stylus or finger within a display frame period 600 can be referred to as LHB intervals or touch sensing intervals. Touch driving performed for two or more LHB intervals within a display frame period can be referred to as LHB driving.

[0098] For example, such as Figure 6 As shown, when 16 display intervals and 16 touch sensing intervals are executed alternately and repeatedly within a display frame time period 600, the 16 touch sensing intervals can be referred to as LHB#1 (601), LHB#2 (602), LHB#3 (603), ..., LHB#16 (616), respectively.

[0099] The following will refer to Figures 7 to 10 This describes an implementation method for sensing touch in low-speed driving mode.

[0100] Figure 7 This is a diagram illustrating touch sensing operation in a low-speed driving mode according to an embodiment.

[0101] Reference Figure 7 In a low-speed drive mode (e.g., LRR mode), the display device may include data write intervals 711 and 721 and data hold intervals (e.g., dummy segments) 712 and 722 within a display frame 710, 720.

[0102] For example, the first display frame 710 may include a first data write interval 711 and a first data hold interval 712. The second display frame 720 may include a second data write interval 721 and a second data hold interval 722. The first data hold interval 712 may be located between the first data write interval 711 and the second data write interval 721.

[0103] According to the implementation method, assuming that in low-speed drive mode, one display frame is 50ms, then the display refresh rate can be 20Hz. Figure 7 In this example, we assume that the data write interval in a display frame is 16.6ms and the data hold interval is 33.4ms. In low-speed drive mode, the touch sensing mode can operate as an idle mode (e.g., touch idle mode). The display refresh rate in low-speed drive mode can be determined based on the width of the data hold interval.

[0104] According to an embodiment, in the first data write interval 711 or the second data write interval 721, as shown, the display device can alternately repeat the display interval indicated by "D" and the touch sensing interval indicated by "T" (e.g., LHB interval). According to an embodiment, the display driving circuit can be configured to output a display driving signal in the display interval within the first data write interval 711 or the second data write interval 721.

[0105] According to the implementation, the touch driving circuit can sense a touch in any one of the multiple touch sensing intervals in the first data writing interval 711 or the second data writing interval 721 to detect or identify the presence or absence of a touch. As an example, in order to reduce current consumption, the display device can perform touch sensing (711a, 721a) in the last touch sensing interval (e.g., the last LHB) of the multiple touch sensing intervals included in each data writing interval (711, 721) to detect the presence or absence of a touch.

[0106] For example, to reduce current consumption, the display device can identify (or check) whether a touch has occurred on any of the multiple touch electrodes by detecting the presence or absence of a touch while the multiplexer (MUX) connected to each touch electrode TE of the panel 120 is short-circuited. Figure 7 As shown, when the display device performs a touch sensing 711a and 721a once in the last touch sensing interval (e.g., the last LHB) among the multiple touch sensing intervals included in each data writing interval 711 and 721, the touch sensing frequency in the touch idle mode can be 20Hz, which is the same as the display refresh rate.

[0107] Figure 8This is a diagram illustrating the detection of touch in low-speed driving mode according to an embodiment.

[0108] Reference Figure 8 In a low-speed drive mode (e.g., LRR mode), the display device may include a first data write interval 811 and a first data hold interval (e.g., dummy segment) 812 within the first display frame 810.

[0109] According to one implementation, assuming a display frame is 50ms in low-speed drive mode, the display refresh rate can be 20Hz. Figure 8 In this example, we assume that the data write interval in a display frame is 16.6ms and the data hold interval is 33.4ms. In low-speed drive mode, the touch sensing mode can operate as an idle mode (e.g., touch idle mode). The display refresh rate in low-speed drive mode can be determined based on the width of the data hold interval.

[0110] According to an embodiment, during the first data write interval 811, as shown, the display device may alternately repeat the display interval indicated by "D" and the touch sensing interval indicated by "T" (e.g., LHB interval). According to an embodiment, the display driving circuit may be configured to output a display driving signal during the display interval within the first data write interval 811.

[0111] According to the implementation, the touch driving circuit can sense a touch in any one of the plurality of touch sensing intervals in the first data write interval 811 to detect or identify the presence or absence of a touch. As an example, to reduce current consumption, the display device can perform touch sensing 811a in the last touch sensing interval (e.g., the last LHB) of the plurality of touch sensing intervals included in the first data write interval 811 to detect the presence or absence of a touch. For example, to reduce current consumption, the display device can identify whether a touch has occurred for any of the plurality of touch electrodes by detecting the presence or absence of a touch while the multiplexer MUX connected to each touch electrode TE of the panel 120 is short-circuited.

[0112] According to the implementation method, such as Figure 8 As shown, when identifying whether a touch exists in the last touch sensing interval (e.g., the first touch sensing interval) among the multiple touch sensing intervals included in the first data writing interval 811a, the presence or absence of a touch can be identified, but the touch location cannot be identified. Therefore, it may be impossible to perform a touch location reporting operation.

[0113] Therefore, as a result of identifying (811a) whether a touch exists within the first touch sensing interval, the display device currently operating in low-speed drive mode can continue the first data holding interval 812 according to the end of the first data writing interval 811, even though a touch is detected.

[0114] Next, upon detecting a touch, the display device can switch from a low-speed drive mode to a basic drive mode (e.g., normal mode) after the first data hold interval 812 ends. For example, as the low-speed drive mode switches to the basic drive mode, the display device can change the display refresh rate from 20Hz to 60Hz.

[0115] Therefore, the interval between the second display frame 821 and the third display frame 822 can be 16.6 ms. According to the embodiment, each of the second display frame 821 and the third display frame 822 may include only the data write interval, without including the data hold interval.

[0116] According to an implementation, when a touch is detected within a first touch sensing interval, the touch sensing unit 140 can switch to a touch activation mode. The touch sensing unit 140 can perform multiple touch sensing operations (e.g., 6 times) within a data writing interval.

[0117] For example, as shown in the figure, when six touch sensing operations 821a and 821b are performed in the second data writing interval corresponding to the second display frame 821 and six touch sensing operations 822a and 822b are performed in the third data writing interval corresponding to the third display frame 822, the touch sensing frequency can be 120Hz.

[0118] Reference Figure 8 Six touch sensing operations 821a and 821b can be performed in the first half of the second data writing interval corresponding to the second display frame 821, in three LHBs (e.g., LHB#3, LHB#4 and LHB#5) and in the second half of the second data writing interval corresponding to the second display frame 821, in three LHBs (e.g., LHB#8, LHB#9 and LHB#10).

[0119] Furthermore, six touch sensing operations 822a and 822b can be performed in the first half of the third data writing interval corresponding to the third display frame 822, in three LHBs (e.g., LHB#3, LHB#4, LHB#5) and in the second half of the third data writing interval corresponding to the third display frame 822, in three LHBs (e.g., LHB#8, LHB#9, LHB#10).

[0120] In touch sensing during touch activation mode, full sensing is performed, enabling the identification of the location where a touch occurred. For example, the location of a touch can be identified by sensing the touch of the three LHBs in the first half (e.g., LHB#3, LHB#4, and LHB#5). The location of a touch can be identified by sensing the touch of the last three LHBs in the second half (e.g., LHB#8, LHB#9, and LHB#10).

[0121] According to the implementation method, refer to Figure 8 After a touch is detected at the last LHB of the first data write interval 811, it may take at least as long as the first data hold interval 812 (e.g., a dummy segment) for the location of the touch to be identified (e.g., 33.4 ms or longer). Users touching the screen of the display device in low-speed drive mode may experience lower latency because the touch location is not reported and the touch result is reflected until a time equal to the first data hold interval 812 has elapsed.

[0122] Figure 9 This is a diagram illustrating touch sensing operation in a low-speed driving mode according to an embodiment.

[0123] Reference Figure 9 In a low-speed drive mode (e.g., LRR mode), the display device may include data write intervals 911 and 921 and data hold intervals (e.g., dummy segments) 912 and 922 within a display frame 910, 920.

[0124] For example, the first display frame 910 may include a first data write interval 911 and a first data hold interval 912. The second display frame 920 may include a second data write interval 921 and a second data hold interval 922. The first data hold interval 912 may be located between the first data write interval 911 and the second data write interval 921.

[0125] According to the implementation method, assuming a display frame is 50ms in low-speed drive mode, the display refresh rate can be 20Hz. Figure 9 In this example, we assume that the data write interval in a display frame is 16.6ms and the data hold interval is 33.4ms. In low-speed drive mode, the touch sensing mode can operate as an idle mode (e.g., touch idle mode). The display refresh rate in low-speed drive mode can be determined based on the width of the data hold interval.

[0126] According to an embodiment, in the first data write interval 911 or the second data write interval 921, as shown, the display interval indicated by "D" and the touch sensing interval (e.g., LHB interval) indicated by "T" can be alternately repeated. According to an embodiment, the display driving circuit can be configured to output a display driving signal in the display interval within the first data write interval 911 or the second data write interval 921.

[0127] According to the implementation, the touch driving circuit can sense a touch in any one of the multiple touch sensing intervals in the first data writing interval 911 or the second data writing interval 921, so as to detect or identify the presence or absence of a touch.

[0128] According to an embodiment, the display device can perform touch sensing (911a, 921a) in a previous touch sensing interval other than the last touch sensing interval (e.g., the last LHB) among the plurality of touch sensing intervals included in each of the data writing intervals 911 and 921, to detect the presence or absence of a touch.

[0129] Figure 9 The illustration shows one implementation of performing touch sensing in the fifth touch sensing interval (e.g., LHB#5) among a plurality of touch sensing intervals, but various implementations are not limited to the position described above.

[0130] For example, a touch sensing interval that performs touch sensing in a low-speed drive mode can be set in the first half of each of the data writing intervals 911 and 921.

[0131] As another example, a touch sensing interval for touch sensing in low-speed drive mode can be set before three LHB intervals (e.g., any one of LHB intervals from LHB#1 to LHB#7) among the multiple touch sensing intervals (e.g., multiple LHB intervals) included in each of the data writing intervals 911 and 921, starting from the last LHB interval.

[0132] and Figure 7 and Figure 8 In comparison, Figure 9 In this process, touch sensing is performed in the previous LHB intervals except for the last LHB interval, so that when a touch is detected, full sensing can be performed within the same data write intervals 911 and 921 to identify the touch location before switching to the data hold interval.

[0133] Figure 10 This is a diagram illustrating the detection of touch in low-speed driving mode according to an embodiment.

[0134] Reference Figure 10In a low-speed drive mode (e.g., LRR mode), the display device may include a first data write interval 911 and a first data hold interval (e.g., dummy segment) 912 within the first display frame 910.

[0135] like Figure 9 As illustrated in the description, the display device can perform touch sensing 911a and 921a in each of the plurality of touch sensing intervals included in the data writing intervals 911 and 921, except for the last touch sensing interval (e.g., the last LHB), to detect the presence or absence of a touch.

[0136] Figure 10 The illustration shows one implementation of performing touch sensing in the fifth touch sensing interval (e.g., LHB#5) among a plurality of touch sensing intervals, but various implementations are not limited to the position described above.

[0137] like Figure 10 As shown, in a low-speed drive mode (e.g., LRR mode), as a result of performing touch sensing 911a in the fifth touch sensing interval (e.g., LHB#5) of the first data write interval 911, the first data write interval 911 can end when no touch is detected. When the first data write interval 911 ends, a first data hold interval 912 can be performed. When the first data hold interval 912 ends, a second data write interval 921 can be performed.

[0138] According to the implementation, as a result of performing touch sensing 921a in the fifth touch sensing interval (e.g., LHB#5) of the second data writing interval 921, when... Figure 10 When a touch is detected, full sensing 921b can be performed to identify the touch location within the same data write interval (e.g., a second data write interval 921).

[0139] According to the implementation method, such as Figure 10 As shown, as a result of touch sensing 921a in the fifth touch sensing interval (e.g., LHB#5), when a touch is detected, the touch idle mode can be switched to the touch active mode, and full sensing can be performed.

[0140] For example, when a touch is detected in the second data write interval 921 during low-speed drive mode operation, full sensing can be performed in subsequent touch sensing intervals (e.g., LHB#8, LHB#9, and LHB#10) within the second data write interval 921, so that information corresponding to the touch location (e.g., touch coordinates) can be reported.

[0141] According to the implementation method, refer to Figure 10After a touch is detected at LHB#5 of the second data write interval 921, the touch position can be reported and the touch result reflected within the same data write interval (i.e., the second data write interval 921), thereby reducing low latency.

[0142] Subsequently, when the display device operates in the basic drive mode, the touch position can be updated by performing full sensing 922a and 922b in the third data write interval 922 corresponding to the third display frame.

[0143] Figure 11 This is a flowchart illustrating a touch sensing method according to an embodiment.

[0144] Reference Figure 11 The display device can operate in a low-speed drive mode in which the data holding interval is between the data writing interval (step S1110).

[0145] According to the implementation, in the low-speed driving mode, the display device can output a display driving signal in the display interval within each data writing interval, and sense touch in the touch sensing interval (step S1120).

[0146] According to the embodiment, when a touch is detected during a touch sensing interval (S1130), the display device can switch to a touch activation mode in response to confirming the touch detection (S1140). Thereafter, the display device can identify the location of the detected touch in a subsequent touch sensing interval within the same data writing interval (S1150).

[0147] For example, in low-speed drive mode, after a touch is detected in a touch sensing interval within a specific data writing interval, the touch position is reported and the touch result is reflected within the same data writing interval, thereby reducing the low latency that may occur in low-speed drive mode where there is a data hold interval.

[0148] Industrial availability

[0149] The drive signal output device according to the embodiment and the display device including the drive signal output device can be applied to liquid crystal display (LCD) display devices, organic light-emitting diode (OLED) display devices, plasma display panel (PDP) display devices, etc.

[0150] For example, it can be applied to display panels or touch panels of televisions (TVs), laptops, mobile devices, etc., but is not limited to these.

Claims

1. A drive signal output device, the drive signal output device comprising: The display driving circuit is configured to output a display driving signal in a display interval within a first data write interval in a low-speed driving mode where the data holding interval is between data write intervals. as well as A touch driving circuit configured to detect a first touch within a first touch sensing interval within a first data writing interval, and to identify the position of the first touch within a second touch sensing interval within the first data writing interval. Wherein, the first data writing interval includes the display interval, the first touch sensing interval, and the second touch sensing interval, and Wherein, the first touch sensing interval is configured to precede the last touch sensing interval among a plurality of touch sensing intervals included in the first data writing interval, the second touch sensing interval is located between the first touch sensing interval and the last touch sensing interval within the first data writing interval, and the display interval is located between the first touch sensing interval and the second touch sensing interval.

2. The drive signal output device according to claim 1, wherein, The first data hold interval is located between the first data write interval and the second data write interval.

3. The drive signal output device according to claim 1, wherein, The display refresh rate of the low-speed drive mode is determined based on the width of the data hold interval.

4. The drive signal output device according to claim 1, wherein, The touch driving circuit is configured to identify whether a touch exists or not during the first touch sensing interval.

5. The drive signal output device according to claim 1, wherein, The touch driving circuit is configured to operate in touch activation mode based on recognizing that the first touch was detected during the first touch sensing interval.

6. The drive signal output device according to claim 1, wherein, The touch driving circuit is configured to transmit information to the outside corresponding to the position of the first touch identified in the second touch sensing interval.

7. The drive signal output device according to claim 1, wherein, The first touch sensing interval is set in the first half of the first data writing interval.

8. The drive signal output device according to claim 1, wherein, The first touch sensing interval or the second touch sensing interval is set within a long horizontal blank LHB interval.

9. The drive signal output device according to claim 8, wherein, The first touch sensing interval is set before the last three LHB intervals among the plurality of LHB intervals included in the first data writing interval.

10. The drive signal output device according to claim 1, wherein, The drive signal output circuit is configured to output the display drive signal based on the synchronization signal received from the timing controller.

11. A method for outputting a driving signal, the method comprising the following steps: Operate in a low-speed drive mode where the data retention interval is between the data write intervals; In the low-speed drive mode, a display drive signal is output during the display interval within the first data writing interval; A first touch is detected within a first touch sensing interval, within the first data writing interval; as well as In response to detecting the first touch, the location of the first touch is identified within a second touch sensing interval within the first data writing interval. Wherein, the first data writing interval includes the display interval, the first touch sensing interval, and the second touch sensing interval, and Wherein, the first touch sensing interval is configured to precede the last touch sensing interval among a plurality of touch sensing intervals included in the first data writing interval, the second touch sensing interval is located between the first touch sensing interval and the last touch sensing interval within the first data writing interval, and the display interval is located between the first touch sensing interval and the second touch sensing interval.

12. The driving signal output method according to claim 11, wherein, The step of identifying the first touch detected within the first touch sensing interval within the first data writing interval includes the following steps: It identifies whether a touch exists or not during the first touch sensing interval.

13. The driving signal output method according to claim 11, further comprising the following steps: The operation is performed in touch activation mode based on the recognition that the first touch was detected during the first touch sensing interval.

14. The driving signal output method according to claim 11, wherein, The first touch sensing interval is set in the first half of the first data writing interval.

15. The driving signal output method according to claim 11, wherein, The first touch sensing interval or the second touch sensing interval is set within a long horizontal blank LHB interval.

16. The driving signal output method according to claim 15, wherein, The first touch sensing interval is set before the last three LHB intervals among the plurality of LHB intervals included in the first data writing interval.

17. A display device, the display device comprising: panel; The display driving circuit is configured to output a display driving signal in a display interval within a first data write interval in a low-speed driving mode where the data holding interval is between data write intervals. as well as A touch driving circuit configured to detect a first touch within a first touch sensing interval within a first data writing interval, and to identify the position of the first touch within a second touch sensing interval within the first data writing interval. Wherein, the first data writing interval includes the display interval, the first touch sensing interval, and the second touch sensing interval, and Wherein, the first touch sensing interval is configured to precede the last touch sensing interval among a plurality of touch sensing intervals included in the first data writing interval, the second touch sensing interval is located between the first touch sensing interval and the last touch sensing interval within the first data writing interval, and the display interval is located between the first touch sensing interval and the second touch sensing interval.

18. The display device according to claim 17, wherein, The first touch sensing interval is set in the first half of the first data writing interval.

19. The display device according to claim 17, wherein, The first touch sensing interval or the second touch sensing interval is set within a long horizontal blank LHB interval.

20. The display device according to claim 19, wherein, The first touch sensing interval is set before the last three LHB intervals among the plurality of LHB intervals included in the first data writing interval.

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