Touch display panel and display device

Abstract

This application discloses a touch display panel and a display device. The touch display panel includes a common electrode, pixel electrodes that provide data signals, a constant voltage transmission line that provides constant voltage signals, and a touch generation circuit. The common electrode is multiplexed as a touch electrode. During the touch phase, the touch generation circuit outputs a touch signal with the same phase and different amplitude as the data signal to the touch electrode according to the synchronization control signal. This can keep the voltage difference between the pixel electrode and the common electrode consistent during the touch phase. In other words, the liquid crystal clamping pressure remains unchanged during the touch phase, which improves or avoids display abnormalities such as horizontal lines.

Description

Technical Field

[0001] This application relates to the field of display technology, specifically to a touch display panel and display device. Background Technology

[0002] In touch display panels, there is a voltage difference between different signals, and this voltage difference does not remain constant during the touch phase but changes continuously. This causes the in-plane liquid crystal clamping pressure to change continuously, resulting in display abnormalities such as horizontal lines. Summary of the Invention

[0003] This application provides a touch display panel and display device to alleviate the technical problem of display abnormalities caused by inconsistent liquid crystal clamping during the touch stage.

[0004] In a first aspect, this application provides a touch display panel, which includes a common electrode, a pixel electrode for providing data signals, a constant voltage transmission line for providing constant voltage signals, and a touch generation circuit. The common electrode is multiplexed as a touch electrode. During the touch phase, the touch generation circuit outputs a touch signal with the same phase and different amplitude as the data signal to the touch electrode according to a synchronization control signal.

[0005] In some embodiments, the touch generation circuit also generates a touch signal with the same amplitude as the constant voltage signal based on a synchronization control signal during the display phase.

[0006] In some embodiments, the touch generation circuit includes an amplification module and a selection module. The input terminal of the amplification module is electrically connected to the pixel electrode. The first input terminal of the selection module is electrically connected to the output terminal of the amplification module, the second input terminal of the selection module is electrically connected to the constant voltage transmission line, the control terminal of the selection module receives a synchronization control signal, and the output terminal of the selection module outputs a touch signal.

[0007] In some embodiments, the amplification module includes a first inverting amplification unit and a second inverting amplification unit. The input terminal of the first inverting amplification unit is electrically connected to the pixel electrode. The input terminal of the second inverting amplification unit is electrically connected to the output terminal of the first inverting amplification unit, and the output terminal of the second inverting amplification unit is electrically connected to the first input terminal of the selection module.

[0008] In some embodiments, the first inverting amplification unit includes a first capacitor, a first resistor, a first amplifier, a second resistor, a third resistor, and a fourth resistor. One end of the first capacitor is electrically connected to a pixel electrode; one end of the first resistor is electrically connected to the other end of the first capacitor; the inverting input terminal of the first amplifier is electrically connected to the other end of the first resistor; one end of the second resistor is electrically connected to the other end of the first resistor, and the other end of the second resistor is electrically connected to the output terminal of the first amplifier; one end of the third resistor is electrically connected to a first power supply terminal, and the other end of the third resistor is electrically connected to the non-inverting input terminal of the first amplifier; one end of the fourth resistor is electrically connected to the non-inverting input terminal of the first amplifier, and the other end of the fourth resistor is electrically connected to a ground terminal.

[0009] In some embodiments, the second inverting amplifier unit includes a fifth resistor, a second amplifier, a sixth resistor, and a seventh resistor. One end of the fifth resistor is electrically connected to the output terminal of the first amplifier; the inverting input terminal of the second amplifier is electrically connected to the other end of the fifth resistor; one end of the sixth resistor is electrically connected to the inverting input terminal of the second amplifier, and the other end of the sixth resistor is electrically connected to the output terminal of the second amplifier and the first input terminal of the selection module; one end of the seventh resistor is electrically connected to the non-inverting input terminal of the second amplifier, and the other end of the seventh resistor is electrically connected to the ground terminal.

[0010] In some embodiments, the amplification module includes an eighth resistor, a third amplifier, a ninth resistor, a tenth resistor, and an eleventh resistor. One end of the eighth resistor is electrically connected to a bias voltage terminal; the inverting input terminal of the third amplifier is electrically connected to the other end of the eighth resistor; one end of the ninth resistor is electrically connected to the inverting input terminal of the third amplifier, and the other end of the ninth resistor is electrically connected to the output terminal of the third amplifier and the first input terminal of the selection module; one end of the tenth resistor is electrically connected to a pixel electrode, and the other end of the tenth resistor is electrically connected to the non-inverting input terminal of the third amplifier; one end of the eleventh resistor is electrically connected to the non-inverting input terminal of the third amplifier, and the other end of the eleventh resistor is electrically connected to a ground terminal.

[0011] In some embodiments, the selection module includes a data selector, a first input terminal of which is electrically connected to the output terminal of the amplification module, a second input terminal of which is electrically connected to a constant voltage transmission line, a selection terminal of which receives a synchronization control signal, and an output terminal of which outputs a touch signal.

[0012] In some embodiments, the touch display panel further includes a DC-DC voltage converter, a level conversion chip, and a data driver chip, wherein the level conversion chip is electrically connected to the DC-DC voltage converter; the data driver chip is electrically connected to the DC-DC voltage converter; and the touch generation circuit is integrated in at least one of the DC-DC voltage converter, the level conversion chip, and the data driver chip.

[0013] Secondly, this application provides a display device, which includes the touch display panel in at least one of the above embodiments, wherein the touch display panel is a touch liquid crystal display panel.

[0014] The touch display panel and display device provided in this application output a touch signal with the same phase and different amplitude as the data signal to the touch electrode according to the synchronous control signal during the touch phase through the touch generation circuit. This can keep the pressure difference between the pixel electrode and the common electrode consistent during the touch phase. In other words, the liquid crystal clamping pressure remains unchanged during the touch phase, which improves or avoids display abnormalities such as horizontal lines. Attached Figure Description

[0015] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0016] Figure 1 This is a waveform diagram of data signals and touch signals in related technologies.

[0017] Figure 2 This is a schematic diagram of the structure of a touch display panel provided in an embodiment of this application.

[0018] Figure 3 This is a schematic diagram of the touch generation circuit provided in an embodiment of this application.

[0019] Figure 4 for Figure 3 The diagram shows the waveforms of the data signal and the touch signal.

[0020] Figure 5 This is a schematic diagram of the first type of touch generation circuit provided in the embodiments of this application.

[0021] Figure 6 for Figure 5 The diagram shows waveforms of some of the nodes.

[0022] Figure 7 This is a schematic diagram of a second type of touch generation circuit provided in an embodiment of this application.

[0023] Figure 8 for Figure 7 The diagram shows waveforms of some of the nodes. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Features thus defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more unless otherwise explicitly specified.

[0026] In the touch display panel, such as Figure 1 As shown, the display process includes a display stage DP1 and a touch stage TP1. Since the potential of the touch signals TPDO / TPDE / TPCOM remains constant in both the display stage DP1 and the touch stage TP1, the difference between the potential of the data signal DS of the pixel electrode and the potential of the touch signals TPDO / TPDE / TPCOM changes in the touch stage TP1. Since the touch electrode receiving the touch signals TPDO / TPDE / TPCOM is the same electrode as the common electrode, the voltage difference between the pixel electrode and the common electrode, i.e., the liquid crystal clamping pressure, changes, resulting in display abnormalities such as horizontal lines.

[0027] In view of the aforementioned technical problem of display abnormalities caused by inconsistent liquid crystal clamping in TP1 during the touch phase, this embodiment provides a touch display panel. Please refer to [link to relevant documentation]. Figures 2 to 8 ,like Figure 2 , Figure 3 , Figure 4 As shown, the touch display panel includes a common electrode, a pixel electrode that provides a data signal DS, a constant voltage transmission line that provides a constant voltage signal P_COM, and a touch generation circuit. The common electrode is multiplexed as a touch electrode. In the touch phase TP1, the touch generation circuit outputs touch signals TPDO / TPDE / TPCOM that are in phase with the data signal DS but have different amplitudes to the touch electrode according to the synchronization control signal T_SYNC.

[0028] It is understood that the touch display panel provided in this embodiment outputs touch signals TPDO / TPDE / TPCOM with the same phase and different amplitude as the data signal DS to the touch electrode in the touch generation phase TP1 according to the synchronization control signal T_SYNC. This can keep the voltage difference between the pixel electrode and the common electrode consistent in the touch phase TP1. In other words, the liquid crystal clamping pressure remains unchanged in the touch phase TP1, which improves or avoids display abnormalities such as horizontal lines.

[0029] In one implementation, such as Figure 2 As shown, the touch display panel also includes at least one of a DC-DC voltage converter, a level conversion chip, a data driver chip, a pixel array, a timing controller, flash memory, an input connector, a microcontroller (MCU), a light-emitting diode converter, and a backlight unit.

[0030] The input connectors are electrically connected to the timing controller, the microcontroller DC-DC converter, and the LED converter, respectively, so that the timing controller can receive corresponding signals through the eDP protocol and / or I2C protocol, provide the microcontroller with a 3.3V DC voltage, provide various power signals of different specifications, and provide input signals to the LED converter to drive the backlight unit to provide corresponding backlight.

[0031] The microcontroller communicates with the timing controller via the I2C protocol. The timing controller controls the level conversion chip and data driver chip to operate according to predetermined parameters, driving the pixel array to display the desired image. The DC-DC converter provides the corresponding voltage to the level conversion chip and data driver chip.

[0032] To reduce the space occupied by the touch generation circuit, it can be integrated into at least one of the DC-DC converter, level conversion chip, and data driver chip, or it can be integrated into the timing controller, DC-DC converter, LED converter, or backlight unit.

[0033] In one implementation, such as Figure 3 As shown, the touch generation circuit includes an amplification module 100 and a selection module 200. The input terminal of the amplification module 100 is electrically connected to the pixel electrode. The first input terminal of the selection module 200 is electrically connected to the output terminal of the amplification module 100, and the second input terminal of the selection module 200 is electrically connected to the constant voltage transmission line. The control terminal of the selection module 200 is connected to the synchronization control signal T_SYNC, and the output terminal of the selection module 200 outputs touch signals TPDO / TPDE / TPCOM.

[0034] It should be noted that the synchronization control signal T_SYNC can be output by the timing controller or generated by other control circuits. For example, when the potential of the synchronization control signal T_SYNC is high in the display stage DP1, the touch generation circuit outputs a constant voltage signal P_COM as the touch signal TPDO / TPDE / TPCOM; or, when the potential of the synchronization control signal T_SYNC is low in the touch stage TP1, the touch generation circuit outputs a data signal DS with the same phase but different amplitude as the touch signal TPDO / TPDE / TPCOM, so as to keep the voltage difference between the data signal DS and the touch signal TPDO / TPDE / TPCOM constant in the touch stage TP1.

[0035] In one implementation, such as Figure 4 As shown, in the display stage DP1, the touch generation circuit also generates touch signals TPDO / TPDE / TPCOM with the same amplitude as the constant voltage signal P_COM based on the synchronization control signal T_SYNC.

[0036] It should be noted that the pulse amplitude of the data signal DS can be, but is not limited to, 5V, or other voltage values; the low potential of the data signal DS can be, but is not limited to, 0V, or other voltage values.

[0037] In one implementation, such as Figure 5 As shown, the amplification module 100 includes a first inverting amplification unit 101 and a second inverting amplification unit 102. The input terminal of the first inverting amplification unit 101 is electrically connected to the pixel electrode; the input terminal of the second inverting amplification unit 102 is electrically connected to the output terminal of the first inverting amplification unit 101, and the output terminal of the second inverting amplification unit 102 is electrically connected to the first input terminal of the selection module 200.

[0038] It should be noted that the first inverting amplification unit 101 is used to amplify the input data signal DS in reverse, and the second inverting amplification unit 102 is used to amplify the data signal DS processed by the first inverting amplification unit 101 in reverse. This ensures the amplification effect of the data signal DS and achieves the same direction of the data signal DS through two inversions. In other words, this embodiment achieves the same-direction amplification of the data signal DS.

[0039] In one implementation, such as Figure 5As shown, the first inverting amplifier unit 101 includes a first capacitor C1, a first resistor R1, a first amplifier AP1, a second resistor R2, a third resistor R3, and a fourth resistor R4. One end of the first capacitor C1 is electrically connected to the pixel electrode; one end of the first resistor R1 is electrically connected to the other end of the first capacitor C1; the inverting input terminal of the first amplifier AP1 is electrically connected to the other end of the first resistor R1; one end of the second resistor R2 is electrically connected to the other end of the first resistor R1, and the other end of the second resistor R2 is electrically connected to the output terminal of the first amplifier AP1; one end of the third resistor R3 is electrically connected to the first power supply terminal VCC, and the other end of the third resistor R3 is electrically connected to the non-inverting input terminal of the first amplifier AP1; one end of the fourth resistor R4 is electrically connected to the non-inverting input terminal of the first amplifier AP1, and the other end of the fourth resistor R4 is electrically connected to the ground terminal GND.

[0040] It should be noted that the first inverting amplification unit 101 is used to invert and amplify the input data signal DS. If Figure 6 If the data signal DS shown has a positive pulse, then the output signal of the first inverting amplifier unit 101, i.e. the potential waveform of node BB1, has a negative pulse, and the pulse amplitude can be greater than the pulse amplitude of the data signal DS.

[0041] In one implementation, such as Figure 5 As shown, the second inverting amplifier unit 102 includes a fifth resistor R5, a second amplifier AP2, a sixth resistor R6, and a seventh resistor R7. One end of the fifth resistor R5 is electrically connected to the output terminal of the first amplifier AP1; the inverting input terminal of the second amplifier AP2 is electrically connected to the other end of the fifth resistor R5; one end of the sixth resistor R6 is electrically connected to the inverting input terminal of the second amplifier AP2, and the other end of the sixth resistor R6 is electrically connected to the output terminal of the second amplifier AP2 and the first input terminal of the selection module 200; one end of the seventh resistor R7 is electrically connected to the non-inverting input terminal of the second amplifier AP2, and the other end of the seventh resistor R7 is electrically connected to the ground terminal GND.

[0042] It should be noted that the second inverting amplifier unit 102 is used to invert and amplify the data signal DS processed by the first inverting amplifier unit 101. If Figure 6 The output signal of the first inverting amplifier unit 101, i.e. the potential waveform of node BB1, has a negative pulse. Then the output signal of the second inverting amplifier unit 102, i.e. the potential waveform of node CC1, has the same positive pulse as the data signal DS, and the pulse amplitude can be greater than the pulse amplitude of the data signal DS.

[0043] It should be noted that, in combination Figure 5 , Figure 6As shown, the potential waveforms of the data signal DS, node BB1, and node CC1 are identical in both the touch phase TP1 and the display phase DP1. The difference lies in the timing of the response. In the touch phase TP1, the selection module 200 can be controlled via the synchronization control signal T_SYNC to select the data signal DS as the touch signal TPDO / TPDE / TPCOM. Therefore, the touch signals TPDO / TPDE / TPCOM and data signal DS have the same phase but different pulse amplitudes to maintain the liquid crystal clamping pressure between the pixel electrode and the common electrode constant in the touch phase TP1. In the display phase DP1, the selection module 200 can be controlled via the synchronization control signal T_SYNC to select a constant voltage signal P_COM as the touch signal TPDO / TPDE / TPCOM for corresponding display.

[0044] In one implementation, such as Figure 7 As shown, the amplification module 100 includes an eighth resistor R8, a third amplifier AP3, a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11. One end of the eighth resistor R8 is electrically connected to the bias voltage terminal; the inverting input terminal of the third amplifier AP3 is electrically connected to the other end of the eighth resistor R8; one end of the ninth resistor R9 is electrically connected to the inverting input terminal of the third amplifier AP3, and the other end of the ninth resistor R9 is electrically connected to the output terminal of the third amplifier AP3 and the first input terminal of the selection module 200; one end of the tenth resistor R10 is electrically connected to the pixel electrode, and the other end of the tenth resistor R10 is electrically connected to the non-inverting input terminal of the third amplifier AP3; one end of the eleventh resistor R11 is electrically connected to the non-inverting input terminal of the third amplifier AP3, and the other end of the eleventh resistor R11 is electrically connected to the ground terminal GND.

[0045] It should be noted that this embodiment can positively amplify the pulse amplitude while maintaining the phase of the data signal DS, and can also output touch signals TPDO / TPDE / TPCOM with the same phase as the data signal DS but different pulse amplitudes. Moreover, compared to... Figure 5 As shown, fewer components are used, reducing costs and space requirements, and also reducing the processing path of the data signal DS.

[0046] In one implementation, such as Figure 5 , Figure 7 As shown, the selection module 200 includes a data selector S2. The first input terminal of the data selector S2 is electrically connected to the output terminal of the amplification module 100, and the second input terminal of the data selector S2 is electrically connected to the constant voltage transmission line. The selection terminal of the data selector S2 is connected to the synchronization control signal T_SYNC, and the output terminal of the data selector S2 outputs touch signals TPDO / TPDE / TPCOM.

[0047] It should be noted that, if Figure 8 If the data signal DS shown has a positive pulse, then the output signal of the amplification module 100, i.e. the potential waveform of node CC2, has the same positive pulse as the data signal DS, and the pulse amplitude can be greater than the pulse amplitude of the data signal DS.

[0048] Combination Figure 7 , Figure 8 As shown, the data signal DS and the potential waveform of node CC2 are the same in both the touch phase TP1 and the display phase DP1. The difference lies in the timing of the response. In the touch phase TP1, the selection module 200 can be controlled by the synchronization control signal T_SYNC to select the data signal DS as the touch signal TPDO / TPDE / TPCOM. Therefore, the touch signals TPDO / TPDE / TPCOM and data signal DS have the same phase but different pulse amplitudes to maintain the liquid crystal clamping pressure between the pixel electrode and the common electrode constant in the touch phase TP1. In the display phase DP1, the selection module 200 can be controlled by the synchronization control signal T_SYNC to select the constant voltage signal P_COM as the touch signal TPDO / TPDE / TPCOM for corresponding display.

[0049] In the touch phase TP1, the voltage difference between the data signal DS and the touch signals TPDO / TPDE / TPCOM can be greater than 0V, for example, 3V-6V, specifically, it can be 4.8V, 5.0V, 5.2V, etc. It should be noted that this voltage difference range or specific value is preferably applied to the liquid crystal display panel.

[0050] In one embodiment, this embodiment provides a display device, which includes a touch display panel as described in at least one of the above embodiments, wherein the touch display panel is a touch liquid crystal display panel.

[0051] The display device also includes a memory and a processor; the memory stores computer programs that can run on the processor. The memory includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0052] For example, the display device can be any product or component with touch display functionality, such as a smartwatch, smart bracelet, mobile phone, tablet, or laptop.

[0053] It is understood that since the display device provided in this embodiment includes the touch display panel in at least one of the above embodiments, it can also output touch signals TPDO / TPDE / TPCOM with the same phase and different amplitude as the data signal DS to the touch electrode in the touch generation phase TP1 according to the synchronization control signal T_SYNC. In this way, the voltage difference between the pixel electrode and the common electrode can be kept consistent in the touch phase TP1. That is, the liquid crystal clamping pressure remains unchanged in the touch phase TP1, thereby improving or avoiding display abnormalities such as horizontal lines.

[0054] It should be noted that the touch display panel can be either an IN-CELL type touch display panel or an ON-CELL type touch display panel.

[0055] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0056] The touch display panel and display device provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1.A touch display panel, characterized in that, the touch display panel comprises: a common electrode, which is multiplexed as a touch electrode; a pixel electrode, which provides a data signal; a constant voltage transmission line, which provides a constant voltage signal; a touch generation circuit, which outputs a touch signal with the same phase as the data signal and different amplitude to the touch electrode according to a synchronization control signal in a touch phase; the touch generation circuit comprises: an amplification module, an input end of which is electrically connected with the pixel electrode; a selection module, a first input end of which is electrically connected with an output end of the amplification module, a second input end of which is electrically connected with the constant voltage transmission line, a control end of which is connected with the synchronization control signal, and an output end of which outputs the touch signal. 2.The touch display panel according to claim 1, characterized in that, the touch generation circuit further generates a touch signal with the same amplitude as the constant voltage signal according to a synchronization control signal in a display phase. 3.The touch display panel according to claim 1, characterized in that, the amplification module comprises: a first reverse amplification unit, an input end of which is electrically connected with the pixel electrode; a second reverse amplification unit, an input end of which is electrically connected with an output end of the first reverse amplification unit, and an output end of which is electrically connected with the first input end of the selection module. 4.The touch display panel according to claim 3, characterized in that, the first reverse amplification unit comprises: a first capacitor, one end of which is electrically connected with the pixel electrode; a first resistor, one end of which is electrically connected with the other end of the first capacitor; a first amplifier, an inverting input end of which is electrically connected with the other end of the first resistor; a second resistor, one end of which is electrically connected with the other end of the first resistor, and the other end of which is electrically connected with an output end of the first amplifier; a third resistor, one end of which is electrically connected with a first power supply end, and the other end of which is electrically connected with a non-inverting input end of the first amplifier; a fourth resistor, one end of which is electrically connected with the non-inverting input end of the first amplifier, and the other end of which is electrically connected with a ground end. 5.The touch display panel according to claim 4, characterized in that, the second reverse amplification unit comprises: a fifth resistor, one end of which is electrically connected with the output end of the first amplifier; a second amplifier, an inverting input end of which is electrically connected with the other end of the fifth resistor; a sixth resistor, one end of which is electrically connected with the inverting input end of the second amplifier, and the other end of which is electrically connected with an output end of the second amplifier and the first input end of the selection module; a seventh resistor, one end of which is electrically connected with a non-inverting input end of the second amplifier, and the other end of which is electrically connected with a ground end. 6.The touch display panel of claim 1, wherein, the amplification module comprises: an eighth resistor, one end of the eighth resistor being electrically connected with the bias voltage terminal; a third amplifier, an inverting input terminal of the third amplifier being electrically connected with the other end of the eighth resistor; a ninth resistor, one end of the ninth resistor being electrically connected with the inverting input terminal of the third amplifier, the other end of the ninth resistor being electrically connected with an output terminal of the third amplifier and a first input terminal of the selection module; a tenth resistor, one end of the tenth resistor being electrically connected with the pixel electrode, the other end of the tenth resistor being electrically connected with a non-inverting input terminal of the third amplifier; an eleventh resistor, one end of the eleventh resistor being electrically connected with the non-inverting input terminal of the third amplifier, the other end of the eleventh resistor being electrically connected with a ground terminal. 7.The touch display panel of claim 1, wherein, the selection module comprises a data selector, a first input terminal of the data selector being electrically connected with an output terminal of the amplification module, a second input terminal of the data selector being electrically connected with the constant voltage transmission line, a selection terminal of the data selector being connected with the synchronization control signal, and an output terminal of the data selector outputting the touch signal. 8.The touch display panel of any one of claims 1-7, wherein, the touch display panel further comprises: a direct current voltage converter; a level conversion chip, the level conversion chip being electrically connected with the direct current voltage converter; a data driving chip, the data driving chip being electrically connected with the direct current voltage converter; wherein the touch generation circuit is integrated in at least one of the direct current voltage converter, the level conversion chip, and the data driving chip. 9.A display device, comprising the touch display panel of any one of claims 1-8, the touch display panel being a touch liquid crystal display panel. ​

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