Touch display driving device and method

Abstract

The present invention provides a touch display driving device and method, including: a touch driving module, used to generate a synchronization signal for touch display; a pre-charge and regression module, used to generate a pre-charge signal and a regression signal when the synchronization signal is converted from a high level to a low level; a display driving module, used to obtain a first gate driving signal of a set row that is turned on in advance according to the pre-charge signal; obtain a second gate driving signal and a source driving signal of a set row before the synchronization signal is converted to the high level according to the regression signal; and perform display driving according to the first gate driving signal, the second gate driving signal and the source driving signal. The present invention generates a pre-charge signal and a regression signal, obtains a corresponding driving signal for display driving, and solves the defects in the prior art that the longer the high level is maintained, the more leakage, the waveform attenuation and distortion at the output end, the insufficient pixel charging time, and the more prominent defects.

Description

Technical Field

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

[0002] Touch display devices, namely TDDI devices (Touch and display Driver Integration), have been widely used in the display field. Touch display devices can include display panels and touch panels. As a new generation of display touch technology, it has first-class capacitive touch skills, thinner appearance and lower cost advantages. It is currently widely used in mobile phones / TPCs and will gradually become popular in large sizes in the future. Now TDDI products tend to pursue higher resolutions, higher refresh rates, and more sensitive touch effects. In particular, high-end products will also require support for active pens, which puts higher requirements on product charging rate design.

[0003] The higher the resolution and refresh rate of the TDDI device, the better the touch effect, which requires more touch time. However, the longer the touch time, the longer the high level is maintained, the more leakage there is, the waveform attenuation and distortion at the output end, the pixel charging time is insufficient, and the defect is more prominent. Summary of the invention

[0004] The present invention provides a touch display driving device and method, which are used to solve the defects in the prior art that the longer the level is pulled up, the more leakage occurs, the waveform attenuation and distortion of the output end occurs, the pixel charging time is insufficient, and the defects are more prominent.

[0005] The present invention provides a touch display driving device, comprising:

[0006] A touch control driving module, used to generate a synchronization signal for touch control display;

[0007] A pre-charge and return module, used for generating a pre-charge signal and a return signal when the synchronization signal is converted from a high level to a low level;

[0008] A display driving module is used to obtain a first gate driving signal for a set row that is turned on in advance according to the pre-charge signal; to obtain a second gate driving signal and a source driving signal for a set row before the synchronization signal is converted to the high level according to the regression signal; and to perform display driving according to the first gate driving signal, the second gate driving signal and the source driving signal.

[0009] According to a touch display driving device provided by the present invention, the touch driving module is further used to provide a touch driving signal to the touch display panel and collect touch signals when the synchronization signal is in a high level stage.

[0010] According to a touch display driving device provided by the present invention, the display driving module includes a gate driving module and a source driving module, the gate driving module sends a gate driving signal to the touch display panel, and the source driving module sends a source driving signal to the touch display panel.

[0011] According to a touch display driving device provided by the present invention, the gate driving module generates a multi-phase clock, and the multi-phase clock provides a gate driving signal for each row of the touch display panel based on a shifting circuit.

[0012] According to a touch display driving device provided by the present invention, if the number of rows is set to 1, the first gate driving signal and the second gate driving signal are the same driving signal.

[0013] According to a touch display driving device provided by the present invention, the number of rows is set to an integer greater than 1.

[0014] The present invention also provides a touch display driving method, comprising:

[0015] Acquire a synchronization signal of the touch display, and if the synchronization signal is converted from a high level to a low level, generate a pre-charge signal and a return signal;

[0016] Acquire a first gate drive signal of a set row opened in advance according to the pre-charge signal;

[0017] According to the regression signal, obtaining a second gate driving signal and a source driving signal of a set row before the synchronization signal is converted to the high level;

[0018] Display driving is performed according to the first gate driving signal, the second gate driving signal and the source driving signal.

[0019] The touch display driving device and method provided by the present invention generate a pre-charge signal and a return signal to obtain a corresponding driving signal for display driving, thereby solving the defects in the prior art that the longer the high level is maintained, the more leakage occurs, the waveform attenuation and distortion at the output end, the pixel charging time is insufficient, and the defects are more prominent. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 This is the timing diagram of TDDI products in H_TOUCH mode;

[0022] Figure 2 is a structural schematic diagram of a touch display driving device provided by the present invention;

[0023] Figure 3 This is a schematic diagram of gate drive, source drive and TD_SYNC timing;

[0024] Figure 4 is a schematic diagram of a first embodiment of a pre-charge signal and a return signal;

[0025] Figure 5 This is a schematic diagram of GCK being disturbed by TD_SYNC;

[0026] Figure 6 is a schematic diagram of a second embodiment of a pre-charge signal and a return signal;

[0027] Figure 7 is a schematic diagram of a third embodiment of a pre-charge signal and a return signal;

[0028] Figure 8 It is a flow chart of the touch display driving method provided by the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance.

[0031] Currently, TDDI products are divided into two modes for touch display:

[0032] The first mode is to divide a frame into a display time period and a touch time period when displaying a frame of image. That is, the touch time period is placed after the display time period. The sum of the two time periods is the time of a frame of image. This mode is called V_TOUCH mode.

[0033] The other is to insert the touch time period into the display time period in batches when displaying a frame of picture. That is, in one frame of picture, it will be divided into a cycle of display-touch-display-touch-display from top to bottom. This mode can achieve a higher touch frequency. Therefore, most high-end TDDI products currently use this mode, which is called H_TOUCH mode.

[0034] like Figure 1 As shown, when the TDDI product is in the H_TOUCH mode, the touch stage is inserted into the display stage and switched during the touch time period ( Figure 1 TOUCH) to display time period ( Figure 1 The charging time of the first row of gates after DISPLAY is insufficient, resulting in insufficient charging of the liquid crystal capacitor, which causes horizontal stripes to appear. Figure 1 DISPLAY) to touch time period switch ( Figure 1 In the TOUCH mode, since the display needs to be turned off, the charging time of the previous row of pixels during the touch time period is insufficient, which will also cause poor display of horizontal stripes.

[0035] In order to solve the above-described problems, the present invention proposes GCK retrace technology (G_retrace) and GCK precharge technology (G_precharge), which effectively optimize the problem of poor display due to touch noise while ensuring good touch effect, not only providing good display visual effect, but also ensuring optimal touch signal-to-noise ratio and touch performance. The hardware circuit cost implemented by the present invention is low and can be implemented with only a simple circuit.

[0036] Figure 2 is a schematic diagram of the structure of the touch display driving device provided by the present invention, referring to Figure 2 The present invention provides a touch display driving device, comprising:

[0037] The touch driving module 210 is used to generate a synchronous signal for touch display.

[0038] The pre-charge and return module 220 is used to generate a pre-charge signal and a return signal when the synchronization signal is converted from a high level to a low level.

[0039] The display driving module 230 is used to obtain the first gate driving signal of the set row that is turned on in advance according to the pre-charge signal; obtain the second gate driving signal and the source driving signal of the set row before the synchronization signal is converted to the high level according to the regression signal; and perform display driving according to the first gate driving signal, the second gate driving signal and the source driving signal.

[0040] Specifically, the touch driving module 210 and the display driving module 230 are both connected to the touch display panel 240 . The touch display panel 240 includes an LCD module and a TP module, wherein the TP module is a touch module.

[0041] The touch driving module 210 is also used to provide a touch driving signal to the touch display panel 240 and collect touch signals when the synchronization signal is in a high level stage. Specifically, the touch driving module 210 generates a TP module drive and collects TP raw data (Raw_data). At the same time, the touch driving module 210 generates TD_SYNC (synchronization signal) when the GCK count reaches a configurable number of rows.

[0042] The display driving module 230 includes a gate driving module 231 and a source driving module 232. The gate driving module 231 sends a gate driving signal to the touch display panel 240, and the source driving module 232 sends a source driving signal to the touch display panel 240. During the period when TD_SYNC is at a high potential, GCK stops driving the gate of the touch display panel 240, and the source driving module 232 stops charging the source end of the touch display panel 240. The touch driving module 210 provides a touch driving signal and collects raw_data of the touch module.

[0043] The gate driver module 231 receives the retrace signal, and when TD_SYNC is converted to a low potential, it generates a GCK signal for a row before TD_SYNC is converted to a high potential, and informs the source driver module 232 (SOURCE Driver) to prepare the source data of the row. When TD_SYNC is converted to a low potential, that is, when entering the DISPLAY state, the precharge and regression module 220 generates a retrace signal to inform the GCK driver circuit to turn on the gate start signal GCK of the previous row or the previous two rows, and the gate switch signal of the previous row, or the previous two rows, or the previous N (N=1, 2, 3...) rows. At the same time, the source driver circuit is notified to prepare the source retrace data of the previous N rows.

[0044] When the gate driver module 231 receives the precharge signal, it turns on the virtual GCK signal of the first row after TD_SYNC is converted to a high potential in advance, and turns on the gate switch of the first row after TP in advance, telling the SOURCE Driver that it does not need to prepare data until the source data of the first row after TP is provided after the precharge stage. 2 When TD_SYNC is converted to a low potential, that is, when entering the DISPLAY state, the precharge and retrace module 220 (GCK retrace / precharge circuit) generates a precharge (or pre-open) signal, telling the GCK driver circuit to turn on one or more rows of virtual gate opening signals GCK in advance, and the source driver does not need to provide source data at this time.

[0045] Optionally, the gate driving module generates a multi-phase clock, and the multi-phase clock provides a gate driving signal for each row of the touch display panel based on a shifting circuit.

[0046] Optionally, if the number of rows is set to 1, the first gate driving signal and the second gate driving signal are the same driving signal.

[0047] Optionally, set the number of rows to an integer greater than 1.

[0048] The embodiments of the present invention are further described below in conjunction with the accompanying drawings.

[0049] The gate driver module (hereinafter referred to as GCK Driver) provides a multi-phase clock to Figure 3 , Figure 4 For example, a 4-phase GCK clock is provided, and the 4-phase GCK clock provides a gate switch for each row for the touch display panel (hereinafter referred to as TDDI panel) under a shift circuit (not shown in the figure).

[0050] Figure 3 The figure shows the normal gate drive and source drive timing. In the figure, GCK1, GCK2, GCK3 and GCK4 are the gate switching signals.

[0051] Assume that the first high potential pulse of GCK1 represents the gate switch of the source of the first row, and the corresponding source data SD is L1. When GCK1 is converted to a low potential, the SD of L1 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0052] The first high potential pulse of GCK2 indicates the gate switch of the source of the second row, and the corresponding Source data SD is L2. Similarly, when GCK2 is converted to a low potential, the SD of L2 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0053] The first high potential pulse of GCK3 indicates the gate switch of the source of the third row, and the corresponding Source data SD is L3. Similarly, when GCK3 is converted to a low potential, the SD of L3 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0054] The first high potential pulse of GCK4 indicates the gate switch of the source of the fourth row, and the corresponding Source data SD is L4. Similarly, when GCK4 is converted to a low potential, the SD of L4 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0055] The second high potential pulse of GCK1 indicates the gate switch of the source of the fifth row, and the corresponding Source data SD is L5. Similarly, when GCK1 is converted to a low potential, the SD of L5 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0056] The second high potential pulse of GCK2 indicates the gate switch of the source of the sixth row, and the corresponding Source data SD is L6. Similarly, when GCK2 is converted to a low potential, the SD of L6 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0057] In this way, GCK1~GCK4 keeps shifting and circulating until the last row of source data is fully charged, that is, one frame of display data is refreshed.

[0058] Figure 3 The time segment of DISPLAY is in the low potential segment of TD_SYNC, indicating that the TDDI panel is in the display state, and the time segment of TOUCH is in the high potential segment of TD_SYNC, indicating that the TDDI panel is in the touch state.

[0059] In order to ensure that the touch signal-to-noise ratio and touch accuracy are in a better state, a sufficiently long TD_SYNC high potential time is required, that is, the shorter the T1 time and the T2 time, the better.

[0060] However, the smaller T1 is, the more the gate switch of Lm row ( Figure 3 The more serious the interference of GCK1 at Lm, such as Figure 5 As shown in the TD_RISE segment in the figure, Lm source will not be fully charged to its corresponding source potential. The smaller T2 is, the less time the gate switch pre-opens in the Lm1 (m+1) row. Figure 5As shown in the TD_FALL segment in FIG. 1 , the source of Lm1 will not be fully charged to its corresponding source potential.

[0061] In this way, if good touch performance is to be ensured, horizontal stripes will appear on the display of a row close to the upper edge of TD_SYNC and a row close to the lower edge of TD_SYNC.

[0062] like Figure 5 As shown in the figure, since the rising edge of TD_SYNC (the rising edge indicates that the touch scan is to be turned on) is very close to the gate switch GCK of the Lm (mth row), the impact on GCK will be more serious, so that the GCK of Lm is turned off in advance, resulting in insufficient charging of the source of the Lm row, showing horizontal stripes. Since the falling edge of TD_SYNC (the falling edge indicates that the touch scan is to be turned off) is very close to the gate switch GCK of the Lm1 (m+1th row), the pre-charge time for the gate is insufficient, which will also cause insufficient charging of the source of the Lm1 row, showing horizontal stripes.

[0063] In order to solve the above problems, the G_precharge and G_retrace proposed in the present invention can solve the above problems. Figure 4 The timing diagram of the G_precharge and G_retrace hardware devices of the present invention is shown, and the DISPLAY portion before the rising edge of the touch display synchronization signal TD_SYNC is Figure 3 Same.

[0064] The first high potential pulse of GCK1 indicates the gate switch of the source of the first row, and the corresponding Source data SD is L1. When GCK1 is converted to a low potential, the SD of L1 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0065] The first high potential pulse of GCK2 indicates the gate switch of the source of the second row, and the corresponding Source data SD is L2. Similarly, when GCK2 is converted to a low potential, the SD of L2 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0066] The first high potential pulse of GCK3 indicates the gate switch of the source of the third row, and the corresponding Source data SD is L3. Similarly, when GCK3 is converted to a low potential, the SD of L3 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0067] The first high potential pulse of GCK4 indicates the gate switch of the source of the fourth row, and the corresponding Source data SD is L4. Similarly, when GCK4 is converted to a low potential, the SD of L4 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0068] The second high potential pulse of GCK1 indicates the gate switch of the source of the fifth row, and the corresponding Source data SD is L5. Similarly, when GCK1 is converted to a low potential, the SD of L5 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0069] The second high potential pulse of GCK2 indicates the gate switch of the source of the sixth row, and the corresponding Source data SD is L6. Similarly, when GCK2 is converted to a low potential, the SD of L6 will be locked, that is, it will be filled to the potential corresponding to the source data.

[0070] Similarly, when T1 is very small, the gate switch of Lm row ( Figure 4 The more serious the interference of GCK2 at Lm, such as Figure 5 As shown in the TD_RISE segment, there are also horizontal stripes, but at GRET, or G_retrace, the gate switch of the Lm row is turned on, and the source data SD corresponding to Lm also refreshes the Lm row pixels, thus solving the problem. Figure 5 The corresponding Lm horizontal stripe problem is shown in the TD_RISE segment in the figure. The technical point of G_retrace is that the G_retrace / precharge circuit provides a retrace signal. When TD_SYNC switches to display, one or more rows of gate switch signals GCK are turned on in advance according to the timing of GCK. This is called gate switch signal GCK retrace. The prepared source data re-refreshes the pixels of the row corresponding to the retrace GCK, which is called source retrace.

[0071] G_retrace technology combined with G_ precharge technology can achieve better display effects.

[0072] At the same time, in order to avoid Figure 5 As shown in the TD_FALL snippet in the figure, TD_SYNC transitions from high to low ( Figure 4 In order to solve the problem of insufficient pixel charging in the Lm row in the example, the G_precharge technology ( Figure 4 GPRE), open a row of dummy GCK in advance, and the source data is also dummy data ( Figure 4In this way, the display of Lm1 and Lm rows can be guaranteed not to be affected by touch control, and the signal-to-noise ratio and touch accuracy of the data collected by touch control can be guaranteed. The technical point of G_precharge is that the G_retrace / precharge circuit provides a precharge signal to inform the GCK drive circuit to turn on the gate switch signal GCK of the configurable number of rows in advance, avoiding the problem of insufficient charging of the first row of pixels when TD_SYNC is converted from the touch state to the display, which is equivalent to pre-opening more time for the first row of pixels.

[0073] The G_precharge and G_retrace of the present invention can solve the horizontal stripe problem caused by the touch interference display in the H_TOUCH mode.

[0074] It should be noted that the above description of G_precharge and G_retrace of the present invention is only a special case description and does not represent the whole of the present invention. Figure 6 and Figure 7 Two embodiments of the present invention.

[0075] like Figure 5 In the TD_RISE segment, when TD_SYNC switches to the Touch Panel, that is, when the low-voltage DISPLAY state of TD_SYNC is converted to the TOUCH state, the noise of TD_SYNC may seriously affect the display, and even affect the display of Lm (mth row) and Lm1 (m+1th row), such as Figure 6 At this time, it is necessary to G_retrace two lines Lm and Lm1 when TD_SYNC switches from the TOUCH state to the DISPLAY state. In fact, the number of G_retrace lines can be set according to the actual scenario.

[0076] Figure 7 In the case of one row (Lm) of G_retrace, G_precharge and G_retrace are the same GCK (GCK2). This embodiment turns on the gate switch of G_retrace in advance to precharge the row (Lm) of retrace, which ensures sufficient charging time for the retrace row and is also not affected by TOUCH noise.

[0077] The touch display driving method provided by the present invention is described below. The touch display driving method described below and the touch display driving device described above can be referred to each other.

[0078] like Figure 8 As shown, the present invention also provides a touch display driving method, comprising:

[0079] S810, obtaining a touch display synchronization signal, if the synchronization signal is converted from a high level to a low potential, a pre-charge signal and a return signal are generated.

[0080] S820, acquiring a first gate driving signal of a set row to be turned on in advance according to the pre-charge signal.

[0081] S830, acquiring, according to the regression signal, a second gate driving signal and a source driving signal of a set row before the synchronization signal is converted to the high level.

[0082] S840, performing display driving according to the first gate driving signal, the second gate driving signal and the source driving signal.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A touch display driving device, characterized in that: include: A touch control driving module, used to generate a synchronization signal for touch control display; A pre-charge and return module, used for generating a pre-charge signal and a return signal when the synchronization signal is converted from a high level to a low level; A display driving module, configured to obtain a first gate driving signal of a set row that is turned on in advance according to the pre-charge signal; obtain a second gate driving signal and a source driving signal of a set row before the synchronization signal is converted to the high level according to the regression signal; and perform display driving according to the first gate driving signal, the second gate driving signal and the source driving signal; The display driving module includes a gate driving module and a source driving module, the gate driving module sends a gate driving signal to the touch display panel, and the source driving module sends a source driving signal to the touch display panel; The pre-charge and regression module generates a retrace signal to inform the gate driver module to turn on the gate start signal GCK of the previous row, the previous two rows, or the previous N rows. The pre-charge and regression module generates a pre-charge signal to inform the gate driver module to turn on one or more rows of virtual gate start signals in advance. At this time, the source driver does not need to provide source data.

2. The touch display driving device according to claim 1, characterized in that: The touch driving module is further used to provide a touch driving signal to the touch display panel and collect a touch signal when the synchronization signal is in a high level stage.

3. The touch display driving device according to claim 1, characterized in that: The gate driving module generates a multi-phase clock, and the multi-phase clock provides a gate driving signal for each row of the touch display panel based on a shifting circuit.

4. The touch display driving device according to claim 1, characterized in that: If the number of rows is set to 1, the first gate driving signal and the second gate driving signal are the same driving signal.

5. The touch display driving device according to claim 1, characterized in that: Set the number of rows to an integer greater than 1.

6. A touch display driving method, characterized in that: The touch display driving device according to any one of claims 1 to 5 is implemented, comprising: Acquire a synchronization signal of the touch display, and if the synchronization signal is converted from a high level to a low level, generate a pre-charge signal and a return signal; Acquire a first gate drive signal of a set row opened in advance according to the pre-charge signal; According to the regression signal, obtaining a second gate driving signal and a source driving signal of a set row before the synchronization signal is converted to the high level; Display driving is performed according to the first gate driving signal, the second gate driving signal and the source driving signal.

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