TWI724325B - Touch display device, touch circuit, and touch sensing method - Google Patents

Abstract

Embodiments of the present disclosure relate to a touch display device, a touch circuit, and a touch sensing method. More particularly, by performing differential sensing on touch electrodes, noise components which the touch electrodes receive from display electrodes (e.g., data line, gate line, etc.) may be removed to accurately sense a touch, so that display driving and touch sensing may be normally performed simultaneously. In this manner, the display driving and the touch sensing may be normally performed simultaneously, thereby enabling implementation of a high-resolution display.

Description

Touch display device, touch circuit and touch sensing method

The invention relates to a touch display device, a touch circuit and a touch sensing method.

With the development of the information society, the demand for touch display devices for displaying images has increased in various forms. Recently, various display devices such as liquid crystal display devices, plasma display devices, organic light emitting display devices, etc. have been used.

Among these display devices, the touch display device provides a touch-based input method that allows users to stay away from traditional input methods such as buttons, keyboards, or mice, and input information or commands intuitively and conveniently.

Because this touch display device must provide both the image display function and the touch sensing function, the driving time such as the frame time is divided into the display driving period and the touch driving period. The display driving is completed in the display driving period, and the display driving is performed in the display driving period. The touch driving cycle after the cycle completes touch driving and touch sensing.

In the case of the above-mentioned time-division driving method, in order to complete the display driving and touch-control driving in a time-sharing manner, quite precise timing control is required, and an expensive component for relatively precise timing control is required.

In addition, in the case of the time-division driving method, both the display driving time and the touch driving time are insufficient, so that the image quality and touch sensitivity are both reduced. In particular, there is a problem that high-resolution image quality cannot be provided due to time-division driving.

In this context, on the one hand, the embodiments of the present disclosure provide a display device, a touch circuit, and a touch sensing method, which can complete display driving and touch driving at the same time.

Another aspect of the disclosed embodiments provides a display device, a touch circuit, and a touch sensing method, which can prevent display driving from affecting touch sensitivity.

Another aspect of the disclosed embodiments provides a display device, a touch circuit, and a touch sensing method, which can realize a high-resolution display.

Another aspect of the disclosed embodiments provides a display device, a touch circuit, and a touch sensing method, which can complete touch sensing without being affected by data driving.

Another aspect of the disclosed embodiments provides a display device, a touch circuit, and a touch sensing method, which can sense touch and ensure the maximum display driving time and sufficient pixel charging time.

The disclosed embodiment provides a touch display device including a display panel and a touch circuit. The display panel includes a plurality of data lines, a plurality of gate lines, a plurality of touch electrodes, and a plurality of touch lines electrically connected to the touch electrodes. The touch circuit is used to supply touch driving signals to these electrodes through these touch lines during the display driving period of the touch display device that displays images on the display panel, and is based on the response to the touch driving signals from a plurality of The difference between the plurality of sensing signals received by two or more of the touch electrodes detects the presence or absence of touch of the touch display device.

The disclosed embodiment provides a touch circuit for sensing touch on a display panel. The display panel includes a plurality of data lines, a plurality of gate lines, a plurality of touch electrodes, and a plurality of touch electrodes electrically connected to the touch electrodes. During the display driving cycle of a touch display device that displays images on a display panel, touch lines and touch circuits are used to supply touch driving signals to these touch electrodes through these touch lines. The touch circuits include differential amplifiers. , The differential amplifier is used based on the first sensing signal received from the first touch electrode of the touch electrodes through the first touch line of the touch lines and the second touch line from these touch lines through the The difference between the second sensing signals received by the second touch electrodes of the touch electrodes outputs an output signal to indicate whether the display panel is touched or not.

The embodiment of the present disclosure provides a touch sensing method for a touch display device. The touch display device includes a display panel. The display panel includes a plurality of data lines, a plurality of gate lines, a plurality of touch electrodes, and a plurality of touch electrodes electrically connected to the touch panels. Controlling the plurality of touch lines of the electrodes, the touch sensing method includes: supplying touch driving signals to the touch electrodes through the touch lines during the display driving period of the touch display device displaying images on the display panel; The first touch line through the touch lines receives the first sensing signal from the first touch electrode of the touch electrodes; the second touch line through the touch lines receives the second touch from the touch electrodes The electrode receives the second sensing signal; generates an output signal based on the difference between the first sensing signal and the second sensing signal; and detects the presence or absence of touch of the touch display device based on the output signal.

According to the above-mentioned embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method that can perform display driving and touch driving at the same time can be provided.

In addition, according to the embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method that can prevent display driving from affecting touch sensitivity can be provided.

In addition, according to the embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method capable of realizing a high-resolution display can be provided.

In addition, according to the embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method that can perform touch sensing without being affected by data driving can be provided.

In addition, according to the embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method can be provided, which can ensure maximum display driving time and sufficient pixel charging time while sensing touch.

Hereinafter, some embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. When elements in a drawing are represented by reference numerals, the same reference numerals in different drawings refer to the same elements. In addition, in the following description of the present disclosure, detailed descriptions of known functions and incorporated configurations will be omitted when the subject of the present disclosure is unclear.

In addition, when describing the components of the present disclosure, terms such as first, second, A, B, (a), (b), etc. are used herein. Each of these terms is not used to define the nature, order, or sequence of the corresponding component, but is only used to distinguish the corresponding component from other components. When describing that a specific structural element "connects", "couples" or "contacts" another structural element, it should be understood that another structural element may "connect", "couple" or "contact" this structural element, and this specific structural element Direct connection or direct contact with another structural element.

1 and 2 are system configuration diagrams of the touch display device according to the embodiment of the disclosure.

The touch display device of the embodiment completes the image display function and the touch sensing function (touch input function).

Hereinafter, the configuration for providing the image display function in the touch display device of the embodiment will be described with reference to FIG. 1, and the configuration for providing the touch sensing function in the touch display device of the embodiment will be described with reference to FIG. 2 (touch input Function) configuration.

Please refer to FIG. 1, in order to provide an image display function, the touch display device of the embodiment includes a display panel DISP, a source driving circuit SDC, a gate driving circuit GDC, and a timing controller TCON. A plurality of data lines DL and a plurality of gate lines GL are arranged in the display panel DISP, and a plurality of sub-pixels SP defined by the plurality of data lines DL and the plurality of gate lines GL are arranged. The source driving circuit SDC is used to drive a plurality of data lines DL. The gate drive circuit GDC is used to drive a plurality of gate lines GL. The timing controller TCON is used to control the source drive circuit SDC and the gate drive circuit GDC.

In the display panel DISP, pixel electrodes can be placed in each sub-pixel SP.

The pixel voltage is applied to the pixel electrode of each sub-pixel SP.

In addition, in the display panel DISP, one or two or more common electrodes to which a common voltage is applied are placed.

A common electrode is a tubular electrode formed on the front surface of the display panel DISP.

Two or more common electrodes are regarded as where one tubular electrode is divided into two or more electrodes. Each of the two or more common electrodes has a larger size than one pixel area.

In each sub-pixel SP, a corresponding electric field is formed by the pixel voltage (which may be a data voltage) applied to the corresponding pixel electrode and the common voltage applied to the common electrode.

The timing controller TCON supplies various drive control signals DCS and GCS to the source drive circuit SDC and the gate drive circuit GDC to control the source drive circuit SDC and the gate drive circuit GDC.

This timing controller TCON starts scanning in accordance with the timing implemented in each frame, switches the input image data input from the outside according to the data signal format used in the source drive circuit SDC, outputs the switched image data, and performs the scan according to the appropriate Time control data drive.

In addition to the input image data from the outside (for example, the host system), the various timing signals received by the timing controller TCON include the vertical synchronization signal Vsync, the horizontal synchronization signal Hsync, the input data enable (DE) signal, and the clock signal. CLK etc.

In addition to switching the input image data input from the outside and outputting the switched image data according to the data signal format used in the source drive circuit SDC, the timing controller TCON also receives timing signals such as vertical synchronization signal Vsync, horizontal synchronization signal Hsync, and input Data enabling signal, clock signal CLK, etc., generate various drive control signals, and output various drive control signals generated to the source drive circuit SDC and gate drive circuit GDC, thereby controlling the source drive circuit SDC and the gate drive circuit GDC.

For example, the timing controller TCON output includes various gate drive control signals such as the gate start pulse GSP, the gate shift clock GSC, and the gate output enable signal GOE to control the gate drive circuit GDC.

In addition, the timing controller TCON output includes various data drive control signals DCS such as source start pulse SSP, source sampling clock SSC, source output enable signal SOE to control the source drive circuit SDC.

This kind of timing controller TCON is a control device that includes a timing controller to perform other control functions.

The timing controller TCON may be implemented as a separate component from the source drive circuit SDC, or may be integrated with the source drive circuit SDC and implemented as an integrated circuit.

The source driving circuit SDC receives the image data from the timing controller TCON, and supplies the data voltage to the plurality of data lines DL to drive the plurality of data lines DL. Here, the source drive circuit SDC is also referred to as a data drive circuit.

Such a source driver circuit SDC can be implemented by including at least one source driver integrated circuit SDIC.

Each source driver integrated circuit SDIC includes a shift register, a latch circuit, a digital-to-analog converter DAC, an output buffer, and so on.

In some cases, each source driver integrated circuit SDIC further includes an analog-to-digital converter ADC.

Each source driver integrated circuit SDIC connection can adopt tape automated bonding (TAB) method or chip on glass (COG) method to connect the bonding pad of the display panel DISP, or directly place it on the display On the panel DISP. In some cases, each source driver integrated circuit SDIC is integrated and placed on the display panel DISP. In addition, a chip on film (COF) method can also be used to implement each source driver integrated circuit SDIC, which is mounted on the film connected to the display panel DISP.

The gate driving circuit GDC sequentially supplies scan signals to the plurality of gate lines GL to sequentially drive the plurality of gate lines GL. Here, the gate drive circuit GDC is also referred to as a scan drive circuit.

Such a gate driver circuit GDC can be implemented by including at least one gate driver integrated circuit GDIC.

Each gate driver integrated circuit GDIC includes a shift register, a level shifter, and so on.

Each gate driver integrated circuit GDIC can be connected to the bonding pad of the display panel DISP using tape automated bonding (TAB) method or chip-on-glass (COG) method, or implemented as a gate in the panel ( gate in panel; GIP) type and placed directly on the display panel DISP. In some cases, each gate driver integrated circuit GDIC is integrated and placed on the display panel DISP. In addition, a thin film flip chip method can also be used to implement each gate driver integrated circuit GDIC, which is mounted on the film connected to the display panel DISP.

Under the control of the timing controller TCON, the gate driving circuit GDC sequentially supplies scanning signals of On voltage or Off voltage to a plurality of gate lines GL.

When the gate driving circuit GDC turns on a specific gate line, the source driving circuit SDC converts the image data DATA received from the timing controller TCON into analog data voltages, and supplies the conversion results to the plurality of data lines DL.

The source driving circuit SDC may be located only on one side (for example, either the upper side or the lower side) of the display panel DISP. In some cases, the source driving circuit SDC may be located on both sides (for example, the upper side and the lower side) of the display panel DISP depending on the driving method, the panel design method, and the like.

The gate driving circuit GDC may be located only on one side (for example, either the left side or the right side) of the display panel DISP. In some cases, the gate driving circuit GDC may be located on both sides (for example, the left side and the right side) of the display panel DISP depending on the driving method, panel design method, etc.

Please refer to FIG. 2, the touch display device of the embodiment includes a touch screen panel TSP and a touch circuit TC for sensing touch by using the touch screen panel TSP to provide a touch sensing function.

The touch circuit TC includes a touch drive circuit TDC, a microcontroller MCU, and so on.

The touch drive circuit TDC and the microcontroller MCU can be implemented independently or integrated as a whole for implementation.

On the touch screen panel TSP, a plurality of touch electrodes TE and a plurality of touch lines TL electrically connected to the plurality of touch electrodes TE and corresponding to the plurality of touch electrodes TE are placed.

One touch electrode TE can be a tubular electrode, an electrode with a plurality of holes, a mesh electrode or a comb electrode.

One touch electrode TE can be electrically connected to one or two or more touch lines TL through one or more contact holes CNT or the like.

The plurality of touch lines TL electrically connect the plurality of touch electrodes TE to the touch drive circuit TDC.

The touch driving circuit TDC drives the touch screen panel TSP to generate and output sensing data (touch raw data).

For example, the touch drive circuit TDC supplies touch drive signals to all or part of a plurality of touch electrodes TE placed on the touch screen panel TSP, and detects signals from at least one touch electrode TE to generate and output Sensing data.

The touch driving circuit TDC supplies touch driving signals to one or more touch electrodes TE through one or more touch lines TL, and detects touch sensing signals.

Using the sensing data output by the touch driving circuit TDC, the microcontroller MCU obtains the presence/absence of touch and/or touch coordinates.

The touch display device may be a touch sensing device based on mutual capacitance or a touch sensing device based on self capacitance.

When a touch is sensed based on mutual capacitance, the touch electrodes TE on the touch screen panel TSP are arranged in a matrix form. In this case, each of the touch electrodes TE may be provided in a bar shape.

Alternatively, when a touch is sensed based on mutual capacitance, the touch electrodes TE on the touch screen panel TSP may form touch electrode lines in the column direction and touch electrode lines in the row direction. In this case, the touch electrode TE can be provided in the form of a diamond.

The touch drive circuit TDC supplies touch drive signals to the touch electrode TE or the touch electrode line in the column direction (or row direction), and receives the touch from the touch electrode TE or the touch electrode line in the row direction (or column direction). The sensing signal and the sensing data are generated based on the received touch sensing signal to supply the generated sensing data to the microcontroller MCU. The microcontroller MCU senses the presence/absence of touch or touch coordinates based on the sensing data.

When touch is based on self-capacitance sensing, the touch electrodes TE on the touch screen panel TSP may be electrodes that are electrically separated from each other.

Each touch driving circuit TDC supplies touch driving signals to all or part of the plurality of touch electrodes TE, receives touch sensing signals from the touch electrodes TE supplied with the touch driving signals, and receives touch sensing signals based on the reception The sensing signal generates sensing data to supply the generated sensing data to the microcontroller MCU. The microcontroller MCU senses the presence/absence of touch or touch coordinates based on the sensing data.

As described above, the touch display device of the embodiment of the present disclosure can detect touch based on self-capacitance or mutual capacitance. However, for ease of description, touch detection based on self-capacitance will be described as an example.

The touch screen panel TSP can be manufactured separately from the display panel DISP and joined to the display panel DISP or embedded in the display panel DISP.

When the touch screen panel TSP is embedded in the display panel DISP, the touch screen panel TSP is regarded as a collection of a plurality of touch electrodes TE and a plurality of touch lines TL.

The touch driving circuit TDC and the source driving circuit SDC can be integrated and implemented.

3 is a schematic diagram of the touch display panel TSP embedded in the display panel DISP in the touch display device of the embodiment of the disclosure.

When the touch screen panel TSP is embedded in the display panel DISP, when the display is driven, the plurality of touch electrodes TE placed on the display panel DISP may be common electrodes used. In this case, the display panel DISP is, for example, a liquid crystal display panel.

Therefore, a common voltage is applied to the plurality of touch electrodes TE for image display, and a touch driving signal is applied to all or part of the plurality of touch electrodes TE for touch sensing.

Meanwhile, the display panel DISP may be an organic light emitting display panel. In this case, the plurality of touch electrodes TE and the plurality of touch lines TL are located on an encapsulation layer placed on the common electrode, and the common electrode is placed on the front surface of the display panel DISP and a common voltage is applied.

Here, the common electrode placed on the front surface of the display panel DISP of the organic light emitting display panel can be the cathode in the anode (corresponding to the pixel electrode) and the organic light emitting diode (OLED) in each sub-pixel SP. ) The cathode and the common voltage can be the cathode voltage.

In this case, each of the plurality of touch electrodes TE is provided in the form of a tubular electrode, in which there is no open area. At this time, each of the plurality of touch electrodes TE may be a transparent electrode for light emission in the sub-pixel SP.

Alternatively, each of the plurality of touch electrodes TE may be a mesh electrode with a plurality of opening areas. At this time, in each of the plurality of touch electrodes TE, each opening area corresponds to the light-emitting area of the sub-pixel SP (for example, the area where a part of the anode is located).

Meanwhile, regarding the size of the touch electrode, the area of each of the plurality of touch electrodes TE may overlap the area of two or more sub-pixels SP.

That is, the area size of one touch electrode TE corresponds to the area size of two or more sub-pixels SP.

One touch electrode TE can overlap two or more gate lines GL.

One touch electrode TE and two or more gate lines GL are insulated from each other.

One touch electrode TE can overlap two or more data lines DL.

One touch electrode TE and two or more data lines DL are insulated from each other.

Please refer to FIG. 2 and FIG. 3, a plurality of touch lines TL in the touch screen panel TSP are insulated from each other.

2 and 3, the plurality of touch lines TL are arranged along the same direction as the plurality of data lines DL.

In this case, the data line DL parallel to the touch line TL affects the touch electrodes TE arranged in the same direction. That is, the voltage state of the data line DL parallel to the touch line TL affects the voltage state of the touch electrodes TE arranged in the same direction.

Alternatively, a plurality of touch lines TL are arranged along the same direction of the plurality of gate lines GL.

In this case, the gate line GL parallel to the touch line TL affects the touch electrodes TE arranged in the same direction. That is, the voltage state of the gate line GL parallel to the touch line TL affects the voltage state of the touch electrodes TE arranged in the same direction.

4 is a schematic diagram of the time-division driving of the touch display device of the disclosed embodiment, and FIG. 5 is a schematic diagram of the time-free driving of the touch display device of the disclosed embodiment.

Hereinafter, it is assumed that a plurality of touch electrodes TE are used as common electrodes for display driving.

The touch display device of the embodiment of the disclosure completes the driving operation according to the time division driving method and/or the time independent driving method.

Please refer to FIG. 4, when the time division driving method is used to complete the driving operation, in each of the display driving period and the touch driving period of the completed time division, the touch display device of the embodiment of the present disclosure is completed for providing image display Function display driver and touch driver for providing touch sensing function.

The display driving cycle and the touch driving cycle are controlled in timing by the touch synchronization signal TSYNC.

During the display driving period, the common voltage of the DC voltage is applied to the plurality of touch electrodes TE.

Here, the common voltage is a voltage that forms an electric field with the pixel voltage applied to the pixel electrode of each sub-pixel.

During the touch driving period, the touch driving signal TDS is applied to all or part of the plurality of touch electrodes TE.

At this time, the touch drive signal TDS or the corresponding signal is applied to all or part of the plurality of data lines DL. The touch driving signal TDS or a signal corresponding to the touch driving signal is further applied to all or part of the gate line GL.

The touch drive signal TDS is a signal whose voltage level is variable.

The touch drive signal TDS can be called an AC signal, a modulation signal or a pulse signal.

Please refer to FIG. 5, when the driving operation is completed according to the time-independent driving method, the touch display device of the embodiment of the disclosure simultaneously completes the display driving for providing the image display function and the touch driving for providing the touch sensing function. The time-independent driving method is also called a simultaneous driving method.

One frame time corresponds to one or more active times and one or more blank times.

When the time-independent driving method is used to complete the driving operation, the touch display device of the embodiment supplies the data voltage VDATA to the data line DL during the active time of each frame time, and can supply the touch driving signal TDS to a plurality of touches at this time. Control electrode TE.

The touch driving signal TDS is a signal used to drive the touch electrode TE for touch sensing, and may be a common voltage that allows the touch electrode TE to be used as a common electrode for display driving.

When the touch display device of the disclosed embodiment adopts the time-independent driving method to complete the driving operation, the common voltage and the pixel voltage applied to the pixel electrode of each sub-pixel form an electric field, and the common voltage is its voltage level The variable signal is not a DC voltage.

This common voltage is called an AC signal, a modulation signal, or a pulse signal.

When the touch display device of the embodiment of the disclosure completes the driving operation according to the time-independent driving method, the plurality of touch electrodes TE are common electrodes divided into several groups, and the touch driving signal TDS is regarded as a common voltage.

Meanwhile, the touch display device of the disclosed embodiment can always use the time-division driving method to complete the driving operation, can always use the time-independent driving method to complete the driving operation, or can simultaneously use the time-division driving method and the time-independent driving method to complete the driving operation.

FIG. 6 is a simplified schematic diagram of the touch driving circuit TDC of the single sensing method of the touch display device of the disclosed embodiment.

Please refer to FIG. 6, the touch display device of the embodiment of the present disclosure can drive a plurality of touch electrodes TE sequentially or simultaneously, and separate the touch electrodes TE from each other for sensing.

In this way, the method of separating the touch electrodes TE from each other for sensing is called a single sensing method or a single ended method.

Through the first touch line TL1 and the second touch line TL2, the first touch electrode TE1 and the second touch electrode TE2 that overlap with a display electrode (for example, a data line or a gate line) on the display panel DISP Electrically connected to the touch drive circuit TDC.

The touch driving circuit TDC includes a sensing unit for the first touch electrode TE1 and a sensing unit for the second touch electrode TE2.

Regarding the sensing unit used for the first touch electrode TE1, the touch driving circuit TDC includes a first preamplifier P-AMP1, an amplifier A-APM1, a first integrator INTG1, and the like. The first preamplifier P-AMP1 is used to receive the first sensing signal TSS1 through the first touch line TL1. The amplifier A-APM1 is used to amplify the signal output by the first pre-amplifier P-AMP1. The first integrator INTG1 is used to integrate the signal output by the amplifier A-APM1.

Regarding the sensing unit used for the second touch electrode TE2, the touch driving circuit TDC includes a second preamplifier P-AMP2, an amplifier A-APM2, a second integrator INTG2, and so on. The second preamplifier P-AMP2 is used to receive the second sensing signal TSS2 through the second touch line TL2. The amplifier A-APM2 is used to amplify the signal output by the second pre-amplifier P-AMP2. The second integrator INTG2 is used to integrate the signal output by the amplifier A-APM2.

The first preamplifier P-AMP1 includes a non-inverting input terminal, an inverting input terminal, and an output terminal. The non-inverting input terminal is used to receive the touch drive signal TDS. The inverting input terminal is used for outputting the touch driving signal TDS to the first touch line TL1 and receiving the first sensing signal TSS1 from the first touch line TL1. The output terminal is used to output the first sensing signal TSS1 and a signal corresponding to the first sensing signal TSS1.

The feedback capacitor Cfb1 is connected between the inverting input terminal and the output terminal of the first preamplifier P-AMP1.

The second preamplifier P-AMP2 includes a non-inverting input terminal, an inverting input terminal, and an output terminal. The non-inverting input terminal is used to receive the touch drive signal TDS. The inverting input terminal is used for outputting the touch driving signal TDS to the second touch line TL2 and receiving the second sensing signal TSS2 from the second touch line TL2. The output terminal is used to output the second sensing signal TSS2 or a signal corresponding to the second sensing signal TSS2.

The feedback capacitor Cfb2 is connected between the inverting input terminal and the output terminal of the second preamplifier P-AMP2.

The sensing unit used for the first touch electrode TE1 and the sensing unit used for the second touch electrode TE2 are different from each other.

Or, when sensing the first touch electrode TE1 and the second touch electrode TE2 in different time zones, the sensing unit used for the first touch electrode TE1 and the sensing unit used for the second touch electrode TE2 may be the same.

As described above, in the case of a single sensing method, through the coupling between the display electrode such as the data line DL and the touch electrode TE, the voltage change of the display electrode affects the touch sensing signal TSS. Correspondingly, malfunctions of touch sensing may occur, and touch sensitivity may be significantly reduced.

As shown in FIG. 4, when the touch display device of the present disclosure uses a time division method to complete the driving operation, when there is no voltage change of the display electrode such as the data line DL, the touch driving and sensing operation is completed. In this way, the coupling effect between the display electrode such as the data line DL and the touch electrode TE is minimized.

However, when the touch display device of the disclosed embodiment adopts the time division method to complete the driving operation method, because the time for touch driving and sensing must be allocated separately within a frame time, the display driving time may be shorter .

In particular, when the touch display device of the disclosed embodiment is applied to a high-resolution display, the satisfactory display driving time under high-resolution may be very short, and it is difficult to ensure sufficient pixels when viewed in pixel units. Charging time.

Therefore, there is an urgent need for a method that can minimize the coupling effect between the display electrode such as the data line DL and the touch electrode TE when the time-independent driving method is used to complete the driving operation to realize a high-resolution display.

Hereinafter, the method for minimizing the coupling effect between the display electrode such as the data line DL and the touch electrode TE when the time-independent driving method is used to complete the driving operation to realize a high-resolution display will be described.

7 to 10 are schematic diagrams of a touch driving circuit in a differential sensing method of a touch display device according to various embodiments of the disclosure.

The touch display device of the embodiment of the disclosure includes a display panel DISP in which a touch screen panel TSP is embedded, and a touch circuit TC for sensing touch, and displays images through the display panel DISP.

On the display panel embedded in the touch screen panel TSP, a plurality of data lines DL and a plurality of gate lines GL are placed, a plurality of touch electrodes TE are placed, and a plurality of touch electrodes TE are connected and correspond to them. The plural touch lines TL.

The touch circuit TC adopts a time-independent driving method to drive the touch electrode TE, and adopts a differential sensing method to sense the touch electrode TE.

That is, during the display driving period, the touch circuit TC obtains the presence/absence and/or touch coordinates of touch based on the sensing data. The sensing data includes a plurality of touch lines TL from the first touch line TL1 and The value corresponding to the difference between the first sensing signal TSS1 and the second sensing signal TSS2 respectively received by the second touch line TL2, and the data voltage VDATA is applied to the plurality of data lines DL during the display driving period.

As described above, by removing the noise components generated by the display electrodes in the two touch electrodes TE1 and TE2, touch sensing is completed. In other words, touch driving and sensing eliminate the influence caused by display driving. Therefore, the display driving and the touch driving can be completed normally regardless of the time when the touch driving is completed at the same time. Therefore, the maximum display driving time and sufficient pixel charging time can be ensured, thereby realizing a high-resolution display.

Hereinafter, the touch driving circuit TDC in the touch circuit TC will be described in more detail with reference to FIGS. 7 to 10, for driving the touch electrode TE using a time-independent driving method, and sensing the touch electrode TE using a differential sensing method. .

7 to 10 are schematic diagrams of the touch drive circuit TDC of the differential sensing method of the touch display device of the disclosed embodiments.

Please refer to FIGS. 7 to 10, the touch drive circuit TDC in the touch circuit TC selects two or more touch electrodes TE1 corresponding to two or more touch lines TL1 and TL2 among the plurality of touch lines TL And TE2 receive two or more sensing signals TSS1 and TSS2.

Please refer to FIGS. 7 to 10, the touch drive circuit TDC in the touch circuit TC includes a differential amplifier D-AMP, which is electrically connected to the first touch line TL1 of the plurality of touch lines TL and The second touch line TL2.

Referring to FIGS. 7 to 10, during the display driving period in which the data voltage VDATA is applied to the plurality of data lines DL, the differential amplifier D-AMP outputs an output signal, which is connected to the plurality of touch lines TL through the first The difference between the first sensing signal TSS1 received by a touch line TL1 from the first touch electrode TE1 and the second sensing signal TSS2 received from the second touch electrode TE2 through the second touch line TL2 is proportional to the difference .

Please refer to FIGS. 7 to 10, the touch driving circuit TDC in the touch circuit TC further includes an integrator INTG. The integrator INTG integrates and outputs the output signal from the differential amplifier D-AMP or the signal obtained by processing the output signal (for example, the signal obtained by amplifying the output signal).

Here, the integral value output by the integrator INTG is a value proportional to "TSS1-TSS2" or a value proportional to "TSS2-TSS1".

As mentioned above, the two touch electrodes TE1 and TE2 are differentially sensed to remove the noise components received by the two touch electrodes TE1 and TE2 from the display electrodes (for example, data lines, gate lines, etc.), thereby completing the touch Control sensing. In other words, touch driving and sensing can eliminate the influence caused by display driving. Therefore, the display driving and the touch driving can be completed normally regardless of the time when the touch driving is completed at the same time. Therefore, the maximum display driving time and sufficient pixel charging time can be ensured, thereby realizing a high-resolution display.

Please refer to FIGS. 7 to 10, the touch driving circuit TDC in the touch circuit TC supplies the touch driving signal TDS to the first touch electrode TE1 and the second touch electrode TE2 during the display driving period, and from the first touch The control electrode TE1 and the second touch electrode TE2 receive the first sensing signal TSS1 and the second sensing signal TSS2.

That is, during the display driving period, a differential sensing method is used to sense touch based on self-capacitance.

The touch drive circuit TDC further includes an analog-digital converter (not shown) for converting the integrated value output by the integrator INTG into a digital sensing value.

The sensing data includes the digital sensing value generated by the analog-digital converter, and the touch driving circuit TDC outputs the sensing data.

The touch circuit TC includes a touch drive circuit TDC and a microcontroller MCU. The touch driving circuit TDC is used for outputting sensing data, and the sensing data includes the value corresponding to the difference of the sensing signals corresponding to the two touch electrodes during the display driving period. Based on the sensing data output by the touch drive circuit TDC during the display drive period, the microcontroller unit MCU is used to sense the presence/absence of touch or touch coordinates.

As described above, during the display driving period, the touch display device of the embodiment of the present disclosure uses the touch driving circuit TDC and the microcontroller MCU constituting the touch circuit TC to complete the touch driving and touch sensing processes.

During the display driving period, the touch driving circuit TDC in the touch circuit TC supplies the touch driving signal TDS to the plurality of touch electrodes TE.

At this time, during the display driving period, the touch driving signal TDS supplied to the plurality of touch electrodes TE may be a common voltage applied to the front surface of the display panel DISP.

For example, the touch driving signal TDS may be a common voltage, which forms a capacitance with the data voltage VDATA supplied to each of two or more sub-pixels SP overlapping each touch electrode TE.

That is, during the display driving period, the touch driving signal TDS can be a voltage that forms a capacitor with the data voltage VDATA supplied to each of the two or more sub-pixels SP overlapping the first touch electrode TE1, and The voltage of the capacitor is formed with the data voltage VDATA supplied to each of the two or more sub-pixels SP overlapping the second touch electrode TE2.

During the display driving period, the touch driving signal TDS supplied to the plurality of touch electrodes TE is a signal that its voltage level changes with respect to the touch driving.

When the touch display device of the embodiment of the disclosure uses a time-independent driving method to complete the driving operation, the plurality of touch electrodes are common electrodes, and the touch driving signal TDS is a common voltage, and is supplied to the common electrode during the display driving period The common voltage is regarded as a signal of its voltage level change.

As mentioned above, the touch driving signal TDS is used as a common voltage for display driving. Therefore, the touch display device of the embodiment of the present disclosure can use a time-independent driving method to effectively drive the display panel DISP in which the touch screen panel TSP is embedded.

Please refer to FIGS. 7 to 10, the touch driving circuit TDC in the touch circuit TC further includes a first preamplifier P-AMP1 and a second preamplifier P-AMP2. The first preamplifier P-AMP1 is used for receiving the first sensing signal TSS1 through the first touch line TL1 of the plurality of touch lines TL, and outputting the first input signal IN1 to the differential amplifier D-AMP. The second preamplifier P-AMP2 is used for receiving the second sensing signal TSS2 through the second touch line TL2 of the plurality of touch lines TL, and outputting the second input signal IN2 to the differential amplifier D-AMP.

As mentioned above, by providing the first preamplifier P-AMP1 and the second preamplifier P-AMP2 at the front end of the signal detection configuration (for example, analog-to-digital converter), it is possible to avoid signal attenuation and noise caused by The signal to noise ratio (SNR) is degraded, so that each of the first touch electrode TE1 and the second touch electrode TE2 can more accurately complete the signal detection.

Referring to FIGS. 7 to 10, the first preamplifier P-AMP1 has a first non-inverting input terminal A1, a first inverting input terminal B1, and a first output terminal C1.

The touch driving signal TDS is input to the first non-inverting input terminal A1 of the first preamplifier P-AMP1.

The first inverting input terminal B1 of the first preamplifier P-AMP1 outputs the touch driving signal TDS to the first touch line TL1, and receives the first sensing signal TSS1 from the first touch line TL1.

The first output terminal C1 of the first preamplifier P-AMP1 outputs the first input signal IN1 to the differential amplifier D-AMP.

The second preamplifier P-AMP2 has a second non-inverting input terminal A2, a second inverting input terminal B2, and a second output terminal C2.

The second non-inverting input terminal A2 of the second preamplifier P-AMP2 receives the touch driving signal TDS.

The second inverting input terminal B2 of the second preamplifier P-AMP2 outputs the touch driving signal TDS to the second touch line TL2, and receives the second sensing signal TSS2 from the second touch line TL2.

The second output terminal C2 of the second preamplifier P-AMP2 outputs the second input signal IN2 to the differential amplifier D-AMP.

The first non-inverting input terminal A1 and the second non-inverting input terminal A2 are electrically connected to each other.

Therefore, the touch driving signal TDS is simultaneously input to the first non-inverting input terminal A1 of the first preamplifier P-AMP1 and the second non-inverting input terminal A2 of the second preamplifier P-AMP2.

In addition, the touch driving signal TDS is simultaneously output to the first inverting input terminal B1 of the first preamplifier P-AMP1 and the second inverting input terminal B2 of the second preamplifier P-AMP2.

Therefore, the touch driving signal TDS is applied to the first touch electrode TE1 through the first touch line TL1, and at the same time is applied to the second touch electrode TE2 through the second touch line TL2.

The first feedback capacitor Cfb1 is connected between the first inverting input terminal B1 and the first output terminal C1 of the first preamplifier P-AMP1.

The second feedback capacitor Cfb2 is connected between the second inverting input terminal B2 and the second output terminal C2 of the second preamplifier P-AMP2.

As mentioned above, the use of the first preamplifier P-AMP1 and the second preamplifier P-AMP2 can effectively complete the driving signal supply for touch driving and the sensing signal detection for touch sensing. Thus, the touch is sensed based on self-capacitance.

Please refer to FIG. 8, the touch driving circuit TDC in the touch circuit TC further includes an amplifier A-AMP, which is connected between the differential amplifier D-AMP and the integrator INTG.

By using this additional amplifier A-AMP, the signal output by the differential amplifier D-AMP is amplified and integrated. Therefore, a larger (higher) touch sensing value can be obtained, thereby increasing the touch sensitivity.

Please refer to FIG. 9, the touch driving circuit TDC in the touch circuit TC further includes a first amplifier AMP1 and a second amplifier AMP2. The first amplifier AMP1 is connected between the first preamplifier P-AMP1 and the differential amplifier D-AMP. The second amplifier AMP2 is connected between the second preamplifier P-AMP2 and the differential amplifier D-AMP.

By further using the first amplifier AMP1 and the second amplifier AMP2, the first input signal IN1 and the second input signal IN2 input to the differential amplifier D-AMP are amplified. Therefore, the signal output to the differential amplifier D-AMP is increased, and a larger (higher) touch sensing value can be obtained, thereby increasing the touch sensitivity.

Please refer to Figure 10, the touch drive circuit TDC further includes a multiplexer circuit MUX, which is used to select two control signals Q1 and Q2 input from the microcontroller unit MCU, timing controller TCON, internal controller or other control devices. The two touch electrodes TE1 and TE2 are used for differential sensing, and the selected touch electrodes TE1 and TE2 are connected to the differential amplifier D-AMP. Here, each of the two control signals Q1 and Q2 is a control signal corresponding to the two touch electrodes TE1 and TE2 or the two touch lines TL1 and TL2.

In FIG. 10, the amplifying part of the multiplexer circuit MUX is obtained by omitting the circuit configuration between the multiplexer circuit MUX and the differential amplifier D-AMP.

Therefore, through the multiplexer circuit MUX, the first preamplifier P-AMP1 and the second preamplifier P-AMP2 are selectively electrically connected to the first touch line TL1 and the second touch line through the two control signals Q1 and Q2. The control line TL2 is used for signal detection of differential sensing.

According to the aforementioned multiplexer circuit MUX, only a small number of differential sensing units (first and second preamplifiers, differential amplifiers, integrators, etc.) can sense many touch electrodes. There may be a multiplexer circuit MUX for each touch electrode row including two or more touch electrodes TE or for every two or more touch electrode rows. In other words, the multiplexer circuit MUX can select the touch electrode TE for comparison to determine whether touch is present or not. For example, the multiplexer circuit MUX may select adjacent touch electrodes TE1 and TE2 for comparison to determine whether touch is present or not. Alternatively, the multiplexer circuit MUX can select the non-adjacent touch electrodes TE1 and TE3 for comparison to determine the presence or absence of touch.

Hereinafter, the above-mentioned differential sensing method for the two touch electrodes TE1 and TE2 can be further expanded and described. Assuming that there are eight touch electrodes TE1 to TE8 in a touch electrode row, the differential sensing operation between the touch electrodes TE1 and TE2 and the differential sensing between the touch electrodes TE3 and TE4 are completed in the first signal detection interval Operation, differential sensing operation between touch electrodes TE5 and TE6, and differential sensing operation between touch electrodes TE7 and TE8. In the second signal detection interval, the differential sensing operation between the touch electrodes TE2 and TE3, the differential sensing operation between the touch electrodes TE4 and TE5, and the differential sensing operation between the touch electrodes TE6 and TE7 are completed. As for another example of the above-mentioned differential sensing sequence, the differential sensing operations TE1-TE2 between the touch electrodes TE1 and TE2 are sequentially completed, the differential sensing operations TE2-TE3 between the touch electrodes TE2 and TE3, and the touch electrodes TE3 are completed sequentially. Differential sensing operation between TE3 and TE4 TE3-TE4. This differential sensing can also be performed in the reverse order. That is, the differential sensing operation TE4-TE3 between the touch electrodes TE4 and TE3, the differential sensing operation TE3-TE2 between the touch electrodes TE3 and TE2, and the differential sensing operation TE2- between the touch electrodes TE2 and TE1 are completed. TE1.

After completing this differential sensing operation, the microcontroller unit MCU uses the differential sensing value (ie, the sensing value obtained from the output signal output by the differential amplifier D-AMP) to calculate the correspondence of each of the eight touch electrodes TE1 to TE8 The sensed value. For example, by solving the calculation process of the simultaneous equation corresponding to the differential sensing value (that is, the sensing value obtained from the output signal output to the differential amplifier D-AMP), each of the eight touch electrodes TE1 to TE8 A corresponding sensed value is calculated as the solution of the simultaneous equations.

11A and 11B are examples of two touch electrodes TE1 and TE2 for differential sensing in the touch display device of various embodiments of the disclosure.

Please refer to FIGS. 11A and 11B, the first touch electrode TE1 overlaps two or more data lines DL and two or more gate lines GL, and the second touch electrode TE2 overlaps two or more data lines Line DL and two or more gate lines GL.

Please refer to FIG. 11A, the first touch electrode TE1 and the second touch electrode TE2 to be differentially sensed overlap the same data line.

In this case, the two or more data lines DL overlapping the first touch electrode TE1 and the two or more data lines DL overlapping the second touch electrode TE2 may be the same. The two or more gate lines GL overlapping with the first touch electrode TE1 and the two or more gate lines GL overlapping with the second touch electrode TE2 may be different from each other.

In this way, when the two touch electrodes TE1 and TE2 to be differentially sensed are located in the direction of the data line, the effect of removing the noise component generated by the data line during touch sensing can be obtained.

Referring to FIG. 11A, when the first touch electrode TE1 and the second touch electrode TE2 to be differentially sensed overlap the same data line, the first touch line TL1 electrically connected to the first touch electrode TE1 is The different layers overlap the second touch electrode TE2, and are insulated from the second touch electrode TE2 in the display panel DISP.

Alternatively, the second touch line TL2 electrically connected to the second touch electrode TE2 overlaps the first touch electrode TE1 in a different layer, and is insulated from the first touch electrode TE1 in the display panel DISP.

According to this, the touch line TL does not need to be placed in the non-display area. Here, the non-display area is the outer area of the display area where the touch electrode TE is placed. Therefore, the size of the non-display area can be reduced, thereby reducing the frame size of the touch display device.

Meanwhile, referring to FIG. 11A, during the display driving period, the data voltage VDATA supplied to the data line can be synchronized with the touch driving signal TDS supplied to the plurality of touch electrodes TE.

For example, during the display driving period, a time point delayed from the time point when the voltage level of the data voltage VDATA supplied to the data line changes by a certain time is supplied to the touch driving of the plurality of touch electrodes TE The voltage level of the signal TDS can be increased. For example, after a predetermined time delay from the time point when the voltage level of the data voltage VDATA changes, the voltage level of the touch drive signal TDS can be changed from a low potential (or a high potential) to a high potential (or a low potential). In this way, even if touch sensing is completed during the display driving period, the voltage state of the touch electrode TE is less affected by the voltage change of the data line. Therefore, the touch sensing performance during the display driving period can be improved.

Referring to FIG. 11B, the first touch electrode TE1 and the second touch electrode TE2 for performing differential sensing overlap with the same gate line.

In this case, the two or more data lines DL overlapping the first touch electrode TE1 and the two or more data lines DL overlapping the second touch electrode TE2 may be different from each other. The two or more gate lines GL overlapping the first touch electrode TE1 and the two or more gate lines GL overlapping the second touch electrode TE2 may be the same.

In this way, when the two touch electrodes TE1 and TE2 to be subjected to differential sensing are located in the direction of the gate line, the effect of removing the noise component generated by the gate line during touch sensing can be obtained.

Meanwhile, when the display driving and the touch driving are completed at the same time during the time-independent driving period, when the voltage level of the modulated signal type touch driving signal (touch driving signal; TDS) is applied to the touch electrode (TE) ), the data voltage VDATA applied to the data line is the signal form (combination of two signals) obtained by adding the touch drive signal TDS and the initial voltage Used to display images. In one example, the data voltage VDATA is generated by using the gamma voltage in the form of a modulation signal corresponding to the touch driving signal TDS. Therefore, the data voltage VDATA applied to the data line DL has a signal form that swings the amplitude of the touch drive signal TDS at the initial voltage for image display. In this case, the ground voltage applied to the display panel DISP is a DC voltage. In another example, the ground voltage applied to the display panel DISP is modulated corresponding to the touch drive signal TDS. Therefore, the data voltage VDATA applied to the data line DL becomes a signal shape that oscillates with the amplitude of the ground voltage applied to the display panel DISP as the initial voltage changes for image display. Here, the amplitude of the ground voltage corresponds to the amplitude of the touch drive signal TDS.

Similarly, when the display driving and the touch driving are completed at the same time during the time-independent driving period, when the touch driving signal TDS of the modulation signal type whose voltage level is variable is applied to the touch electrode TE, it is applied to the gate electrode. The scan signal of the line GL is a signal form (combination of two signals) obtained by adding the touch driving signal TDS and the gate voltage to display an image. Here, the gate voltage may be the off-level gate voltage (for example, VGL) used to close the gate line, or the open-level gate voltage (for example, VGH) used to open the gate line. In one example, the gate voltage (VGH, VGL) is used to generate the scan signal, and the gate voltage is the type of modulation signal corresponding to the touch drive signal TDS being modulated. Therefore, the scan signal applied to the gate line GL has a signal shape that swings from the gate voltage (VGH, VGL) to the amplitude of the touch drive signal TDS for image display. In this case, the ground voltage applied to the display panel DISP may be a DC voltage. In another representative method, the ground voltage applied to the display panel DISP is modulated corresponding to the touch drive signal TDS. Therefore, the scanning signal applied to the gate line GL has a signal form that oscillates at the gate voltage (VGH, VGL) and the amplitude of the ground voltage applied to the display panel DISP for image display. Here, the amplitude of the ground voltage corresponds to the amplitude of the touch drive signal TDS.

Although some solutions for time-independent driving have been described above through examples, the present invention is not limited thereto, and can be implemented in various ways. Hereinafter, the ground voltage modulation method for the ground voltage applied to the display panel DISP in the time-independent driving method will be described in detail.

12A and 12B are schematic diagrams of ground voltage modulation for time-independent driving in the touch display device of the disclosed embodiment.

Please refer to FIGS. 12A and 12B. In the touch display device of the present disclosure, the touch driving signal TDS used for time-independent driving is the voltage corresponding to the modulated ground voltage GND_M of the display panel DISP grounding.

The modulated ground voltage GND_M of the display panel DISP ground is a signal of the voltage level change.

The touch drive signal TDS corresponds to the frequency and phase of the modulated ground voltage GND_M of the display panel DISP ground.

During the display drive cycle, the microcontroller unit MCU that senses the presence/absence of touch or touch coordinates or the timing controller TCON for display drive control is grounded to the ground voltage GND in the form of direct current voltage, based on this direct voltage form The ground voltage GND of the display panel DISP ground, and the modulation ground voltage GND_M of the display panel DISP ground is the modulation signal.

Regarding the above-mentioned ground modulation and touch drive signal TDS, even if the DC voltage type touch drive signal TDS is applied to the touch electrode TE corresponding to the common electrode placed on the display panel DISP, the display panel DISP is grounded to the modulation The ground voltage GND_M, the touch drive signal TDS is synchronized with the modulated ground voltage GND_M, so that the touch drive signal TDS becomes a signal whose voltage level changes to the same or similar to the modulated ground voltage GND_M.

The ground voltage GND and the modulated ground voltage GND_M in the form of the above DC voltage and the touch drive signal TDS corresponding to the common voltage will be described again.

Here, the ground voltage GND in the form of DC voltage is referred to as the first ground voltage GND A, and the modulated ground voltage GND_M is referred to as the second ground voltage GND B.

The first ground voltage GND A, which is the ground voltage GND in the form of DC voltage, is a DC voltage that maintains a constant voltage, but the second ground voltage GND B corresponding to the modulated ground voltage GND_M is modulated according to the ground voltage GND in the form of DC voltage. Voltage.

That is, the voltage level of the modulated ground voltage GND_M is the voltage of the modulated signal. The ground voltage GND according to the DC voltage does not maintain a constant voltage level, but its voltage level changes with time.

It can be recognized that the touch drive signal TDS corresponding to the common voltage applied to the display panel DISP is also modulated by modulating the ground voltage GND_M.

That is to say, the touch drive signal TDS corresponding to the common voltage is recognized as a modulation signal whose voltage level is in accordance with the time-varying ground voltage GND in the form of a direct current voltage.

However, the touch drive signal TDS corresponding to the common voltage is recognized as a DC voltage, and its voltage level does not change with time compared with the modulated ground voltage GND_M.

In other words, the touch drive signal TDS corresponding to the common voltage can be a signal whose voltage level changes with time according to the ground voltage GND in the form of a direct current voltage. However, according to the modulated ground voltage GND_M, the touch drive signal TDS corresponding to the common voltage can be a signal with a constant voltage level, and the voltage level does not change over time.

Meanwhile, the touch display device of an embodiment of the present disclosure further includes a ground modulation circuit (GMC), which is based on the pulse modulation signal (for example, pulse width modulation signal) output by the microcontroller unit MCU from a DC voltage The ground voltage GND of the form generates a modulated ground voltage GND_M.

When the second ground voltage GND B is generated based on the pulse modulation signal (for example, the pulse width modulation signal), the ground modulation circuit GMC of the touch display device according to an embodiment of the present disclosure generates the second ground voltage GND B, using In this way, the frequency and phase of the second ground voltage GND B match the pulse modulation signal (for example, the pulse width modulation signal).

When the second ground voltage GND B is generated based on the pulse modulation signal PWM, regardless of the amplitude Va of the pulse modulation signal PWM, the ground modulation circuit GMC can generate the second ground voltage GND B with the desired amplitude Vb.

The present disclosure discloses an embodiment of the ground modulation circuit GMC of the touch display device including a voltage level changing circuit such as a level shifter.

The ground modulation circuit GMC of the touch display device according to an embodiment of the present disclosure has a power separation function for separating the first ground voltage GND A in the form of direct current voltage and the second ground voltage GND B in the form of alternating current voltage.

To this end, the ground modulation circuit GMC includes a power separation circuit, and the power separation circuit includes one or more of a flyback converter, an isolated buck converter, and a transformer.

The touch drive signal TDS applied to the plurality of touch electrodes TE placed on the display panel DISP is synchronized with the second ground voltage GND B. The second ground voltage GND B corresponds to the modulation ground that is modulated by the above ground modulation. Voltage GND_M. Therefore, display driving and touch driving can be effectively completed at the same time.

FIG. 13 is a graph showing the touch sensing effect of the differential sensing method of the touch display device according to the embodiment of the disclosure.

In the graph shown in FIG. 13, the X axis is time, and the Y axis is the voltage value output by the integrator INTG in the touch drive circuit TDC.

In the graph shown in FIG. 13, the voltage value 1300 output by the integrator INTG is 0 volts when there is no touch, and the voltage value 1310 output by the integrator INTG according to the single sensing method shown in FIG. The voltage value 1320 output by the integrator INTG of the differential sensing method shown in Fig. 7 to Fig. 10 is shown in the figure.

Please refer to FIG. 13, it can be seen that the voltage value 1320 output by the integrator INTG of the differential sensing method is significantly higher than the voltage value 1310 output by the INTG of the integrator of the single sensing method.

Therefore, when the touch sensing is completed according to the differential sensing method, because the touch sensing is completed with a higher voltage value than the single sensing method, the touch sensitivity can be significantly increased.

FIG. 14 is a flowchart of a touch sensing method of a touch display device according to an embodiment of the disclosure.

Please refer to FIG. 14, the touch sensing method of the touch display device of the embodiment of the present disclosure includes operation S1210, operation S1220, and operation S1230. In operation 1210, during the display driving period in which the data voltage VDATA is applied to the plurality of data lines DL, the first touch line TL1 of the plurality of touch lines TL receives the first sensing signal from the first touch electrode TE1 TSS1, and receiving the second sensing signal TSS2 from the second touch electrode TE2 through the second touch line TL2 of the plurality of touch lines TL. In operation S1220, an output signal corresponding to the difference between the first sensing signal TSS1 and the second sensing signal TSS2 is generated. Operation S1230 obtains the presence/absence of touch or touch coordinates based on the output signal.

When using the above-mentioned sensing method, by differentially sensing the two touch electrodes TE1 and TE2, the noise components received by the two touch electrodes TE1 and TE2 from the display electrodes (for example, data lines, gate lines, etc.) can be Remove to complete touch sensing. In other words, touch driving and sensing can eliminate the influence caused by display driving. Therefore, the display driving and the touch driving can be completed normally regardless of the time when the touch driving is completed simultaneously. Therefore, the maximum display driving time and sufficient pixel charging time can be ensured, thereby realizing a high-resolution display.

As described above, according to the charge sensing method for sensing the amount of charge change between the two touch electrodes TE, the touch display device and the touch circuit TC of the disclosed embodiments basically sense the touch, and have Charge sensing structure (for example, preamplifier with feedback capacitor).

Meanwhile, in addition to the charge sensing method and the charge sensing structure described above, the touch display device and the touch circuit TC of the embodiment of the present disclosure also provide a voltage sensing method and a voltage sensing structure, regardless of the charge change caused by the parasitic capacitance. Sensing can still be achieved. The voltage sensing method and voltage sensing structure will be described below.

Here, when the display driving and the touch driving are simultaneously completed in the time-independent driving method, a change in the voltage state of the data line may cause a change in the charge introduced through the parasitic capacitance.

15 is another representative schematic diagram of the touch drive circuit TDC of the differential sensing method with voltage sensing structure according to the disclosed embodiment.

Compared with the touch drive circuit TDC of the differential sensing method with the charge sensing structure shown in FIGS. 6 to 11A, the difference of the touch drive circuit TDC with the differential sensing method of the voltage sensing structure shown in FIG. 15 is , The first feedback capacitor Cfb1 and the second feedback capacitor Cfb2 in the first preamplifier P-AMP1 and the second preamplifier P-AMP2 are changed to a first resistor R1 and a second resistor R2, and have voltage sensing The touch drive circuit TDC of the differential sensing method of the measurement structure has a resistor Rd connected to the input terminal and the output terminal of the differential amplifier D-AMP.

More specifically, the touch driving circuit TDC of the differential sensing method shown in FIGS. 6 to 11A has a charge sensing structure. According to this charge sensing structure, the first feedback capacitor Cfb1 is electrically connected between the first inverting input terminal B1 and the first output terminal C1 of the first preamplifier P-AMP1, and the second feedback capacitor Cfb2 is electrically connected It is connected between the second inverting input terminal B2 and the second output terminal C2 of the second preamplifier P-AMP2.

The touch driving circuit TDC of the differential sensing method shown in FIG. 15 has a voltage sensing structure. According to this voltage sensing structure, the first resistor R1 is electrically connected between the first inverting input terminal B1 and the first output terminal C1 of the first preamplifier P-AMP1, and the second resistor R2 is electrically connected It is connected between the second inverting input terminal B2 and the second output terminal C2 of the second preamplifier P-AMP2.

The first preamplifier P-AMP1 receives the first sensing signal TSS1 from the display panel DISP, compares the input first sensing signal TSS1 with the touch drive signal TDS corresponding to the reference voltage, and compares the input first sensing signal TSS1 Amplify to output the first voltage value to the first output terminal C1.

The second preamplifier P-AMP2 receives the second sensing signal TSS2 from the display panel DISP, compares the input second sensing signal TSS2 with the touch drive signal TDS corresponding to the reference voltage, and inputs the second sensing signal TSS2 Amplify to output the second voltage value to the second output terminal C2.

Please refer to Figure 15, according to the voltage sensing structure, in the differential amplifier D-AMP, the resistor Rd is electrically connected between the input terminal and the output terminal where the output signal is output, and the first preamplifier P-AMP1 outputs The first voltage value or the second voltage value output by the second preamplifier P-AMP2 is input to this input terminal.

The differential amplifier D-AMP compares the output signal (first voltage value) of the first preamplifier P-AMP1 with the output signal (second voltage value) of the second preamplifier P-AMP2, and compares the two output signals The difference is amplified and output.

16 is a schematic diagram of the output of the integrator INTG in the touch drive circuit of the differential sensing method with a voltage sensing structure of the disclosed embodiment, and FIG. 17 is a schematic diagram of the output of the integrator INTG when the voltage sensing structure of the disclosed embodiment is used A schematic diagram of the data voltage VDATA, the touch drive signal TDS, and the output signal of the differential amplifier D-AMP in the touch drive circuit TDC of the differential sensing method.

Figure 16 is a graph of INTG output when there is no touch and when the integrator is touched with a finger.

As shown in the graph in Figure 16, the output of the integrator INTG when touched with a finger is different from the output of the integrator INTG when there is no touch.

Therefore, even through the voltage sensing method, the touch can be normally sensed.

FIG. 17 shows the data voltage VDATA applied to the data line DL placed on the display panel DISP, the touch drive signal TDS applied to the touch electrode TE placed on the display panel DISP, and the differential in the touch drive circuit TDC The graph of the output signal of the amplifier D-AMP.

As shown in FIG. 17, when the time-independent driving method is used to complete the display driving and the touch driving at the same time, even if the data voltage VDATA changes, the change in the data voltage VDATA minimally affects the output signal of the differential amplifier D-AMP. Therefore, accurate touch sensing can be completed.

According to the above-mentioned embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method that can perform display driving and touch driving at the same time can be provided.

In addition, according to the embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method that can prevent display driving from affecting touch sensitivity can be provided.

In addition, according to the embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method capable of realizing a high-resolution display can be provided.

In addition, according to the embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method that can perform touch sensing without being affected by data driving can be provided.

In addition, according to the embodiments of the present disclosure, a touch display device, a touch circuit, and a touch sensing method can be provided, which can ensure maximum display driving time and sufficient pixel charging time while sensing touch.

The above description and drawings provide examples of the technical concept of the present disclosure for illustrative purposes only. Those with ordinary knowledge in the technical field of the present disclosure may understand various modifications and changes of the form, such as changes in combination, separation, substitution, and configuration, without departing from the basic characteristics of the present disclosure. Therefore, the embodiments disclosed in this disclosure are intended to illustrate the scope of the technical concept of the disclosure, and the scope of the disclosure is not limited by the embodiments. The scope of this disclosure will be understood in the following manner based on the scope of the attached patent application, and all technical concepts included in the equivalent scope of the patent application belong to this disclosure.

TCON‧‧‧Sequence controller SDC‧‧‧Source drive circuit GDC‧‧‧Gate drive circuit DCS‧‧‧Drive control signal GCS‧‧‧Drive control signal DATA‧‧‧Image data DL‧‧‧Data line GL ‧‧‧Gate line DSIP‧‧‧Display panel SP‧‧‧Sub-pixel TSP‧‧‧Touch screen panel TE‧‧‧Touch electrode CNT‧‧‧Contact hole TL‧‧‧Touch line TDC‧‧ ‧Touch drive circuit MCU‧‧‧Micro control unit TC‧‧‧Touch circuit TDS‧‧‧Touch drive signal TSYNC‧‧‧Touch synchronization signal VDATA‧‧‧Data voltage TE1‧‧‧First touch electrode TE2‧‧‧Second touch electrode TL1‧‧‧First touch line TL2‧‧‧Second touch line TSS1‧‧‧First sensing signal TSS2‧‧‧Second sensing signal Cfb1, Cfb2‧‧ ‧Feedback capacitor P-AMP1‧‧‧First preamplifier P-AMP2‧‧‧Second preamplifier A-AMP1‧‧‧Amplifier A-AMP2‧‧‧Amplifier INTG1‧‧‧First integrator INTG2‧‧ ‧Second integrator INTG‧‧‧Integrator D-AMP‧‧‧Differential amplifier IN1‧‧‧First input signal IIN2‧‧‧Second input signal A1‧‧‧First non-inverting input terminal A2‧‧ ‧Second non-inverting input terminal B1‧‧‧First inverting input terminal B2‧‧‧Second inverting input terminal C1‧‧‧First output terminal C2‧‧‧Second output terminal A-AMP‧‧‧ Amplifier AMP1‧‧‧First amplifier AMP2‧‧‧Second amplifier MUX‧‧‧Multiplexer circuit Q1, Q2‧‧‧Control signal GND‧‧‧Ground voltage GND_M‧‧‧Modulate ground voltage GMC‧‧‧Ground Modulation circuit GND B‧‧‧Second ground voltage GND A‧‧‧First ground voltage PWM‧‧‧Pulse modulation signal Va, Vb‧‧‧Amplitude R1‧‧‧First resistor R2‧‧ Two resistors Rd‧‧‧Resistor 1300‧‧‧The voltage value of the integrator INTG output when no touch is 1310‧‧‧ According to the single sensing method shown in Figure 6, the voltage value of the integrator INTG output is 1320‧‧‧according to the figure 7 to Figure 10 shows the differential sensing method integrator INTG output voltage value

1 and 2 are schematic diagrams of the system configuration of the touch display device according to the embodiment of the disclosure. FIG. 3 is a schematic diagram of the display panel in which the touch screen panel is embedded in the touch display device of the disclosed embodiment. 4 is a schematic diagram of time-division driving of the touch display device according to the embodiment of the disclosure. FIG. 5 is a schematic diagram of the time-free driving of the touch display device according to the embodiment of the disclosure. 6 is a simplified schematic diagram of the touch driving circuit of the single sensing method of the touch display device of the disclosed embodiment. 7 to 10 are schematic diagrams of a touch driving circuit in a differential sensing method of a touch display device according to various embodiments of the disclosure. 11A and 11B are examples of two touch electrodes for differential sensing in a touch display device according to various embodiments of the disclosure. 12A and 12B are schematic diagrams of ground voltage modulation for time-independent driving in the touch display device of the disclosed embodiment. FIG. 13 is a graph showing the touch sensing effect of the differential sensing method of the touch display device according to the embodiment of the disclosure. FIG. 14 is a flowchart of a touch sensing method of a touch display device according to an embodiment of the disclosure. 15 is another representative schematic diagram of the touch drive circuit of the differential sensing method with voltage sensing structure according to the disclosed embodiment. FIG. 16 is a schematic diagram of the output of the integrator in the touch driving circuit of the differential sensing method with the voltage sensing structure of the disclosed embodiment. FIG. 17 is a schematic diagram of the data voltage, touch driving signal, and output signal of the differential amplifier when using the touch driving circuit of the differential sensing method with the voltage sensing structure of the disclosed embodiment.

TDS‧‧‧Touch Drive Signal

VDATA‧‧‧Data voltage

Claims (22)

A touch display device includes: a display panel including a plurality of data lines, a plurality of gate lines, a plurality of touch electrodes, and a plurality of touch lines electrically connected to the touch electrodes; and a touch A circuit for supplying a touch driving signal to the touches through the touch lines during a display driving period of the touch display device in which a plurality of data voltages are applied to the data lines to display an image Controlling electrodes, and detecting the presence or absence of a touch of the touch display device based on sensing data including a value corresponding to a difference, wherein the difference is derived from a first touch of the touch electrodes The difference between a first sensing signal received by the control electrode and a second sensing signal received from a second touch electrode of the touch electrodes, the first sensing signal and the second sensing signal In response to the touch drive signal, the supply of the touch drive signal to the touch electrodes and the application of the data voltages to the data lines are executed simultaneously in at least one activity time in a frame time, wherein the The frame time includes one or more active time and one or more blank time. The touch display device according to claim 1, wherein the touch circuit includes: a differential amplifier for during the display driving period, based on the first touch line from the first touch line of the The difference between the first sensing signal received by a touch electrode and the second sensing signal received from the second touch electrode through a second touch wire among the touch wires, and output an output Signal; and an integrator for integrating the output signal and outputting the integrated output signal or a signal-processed integrated output signal. The touch display device according to claim 1, wherein the first touch electrode and the second touch electrode are adjacent to each other. The touch display device according to claim 1, wherein the first touch electrode and the second touch electrode are not adjacent to each other. The touch display device according to claim 1, wherein the touch circuit is used for detecting the presence or absence of touch during the display driving period. The touch display device according to claim 1, wherein the first touch electrode overlaps two of the data lines and two of the gate lines, wherein the second touch electrode and the first A touch electrode overlaps the same two data lines, and overlaps two of the gate lines that are different from the two gate lines overlapped by the first touch electrode. The touch display device according to claim 1, wherein the first touch electrode overlaps two of the data lines and two of the gate lines, wherein the second touch electrode and the first A touch electrode overlaps the same two gate lines, and overlaps two of the data lines that are different from the two data lines overlapped by the first touch electrode. The touch display device according to claim 1, wherein the touch lines include a first touch line and a second touch line, wherein the first touch line overlaps the second touch electrode and is The display panel is insulated, or the second touch line overlaps the first touch electrode and is insulated in the display panel. The touch display device according to claim 1, wherein the touch drive signal has a voltage corresponding to a ground voltage of the display panel, The ground voltage alternates between a plurality of voltage levels of a frequency, and the touch drive signal is in phase with the ground voltage and has a frequency matching the frequency of the ground voltage. The touch display device according to claim 2, wherein the touch circuit further comprises: a first preamplifier for receiving the first sensing signal and outputting a first input signal through the first touch line To the differential amplifier; and a second preamplifier for receiving the second sensing signal through the second touch line and outputting a second input signal to the differential amplifier. The touch display device according to claim 10, wherein the first preamplifier includes: a first non-inverting input terminal to receive the touch drive signal; and a first inverting input terminal to output the touch Controlling the driving signal to the first touch line and receiving the first sensing signal from the first touch line; and a first output terminal for outputting the first input signal to the differential amplifier, and the second The two preamplifiers include: a second non-inverting input terminal for receiving the touch drive signal; a second inverting input terminal for outputting the touch drive signal to the second touch line and from the second touch line The touch wire receives the second sensing signal; and a second output terminal for outputting the second input signal to the differential amplifier. The touch display device according to claim 11, further comprising: a first feedback capacitor electrically connected to the first inverting input terminal of the first preamplifier and the first inverting input terminal of the first preamplifier Between output terminals, and A second feedback capacitor is electrically connected between the second inverting input terminal of the second preamplifier and the second output terminal of the second preamplifier. The touch display device according to claim 11, further comprising: a first resistor electrically connected to the first inverting input terminal of the first preamplifier and the first inverting input terminal of the first preamplifier Between the output terminals and a second resistor is electrically connected between the second inverting input terminal of the second preamplifier and the second output terminal of the second preamplifier. A touch circuit for sensing touch on a display panel. The display panel includes a plurality of data lines, a plurality of gate lines, a plurality of touch electrodes, and a plurality of touch electrodes electrically connected to the touch electrodes. The touch control circuit is used to supply a touch driving signal through the touch control lines during a display driving period of a touch display device when a plurality of data voltages are applied to the data lines to display an image To the touch electrodes, the touch circuit includes: a differential amplifier for receiving a first touch electrode from one of the touch electrodes through a first one of the touch wires A difference between the first sensing signal and a second sensing signal received from a second touch electrode of one of the touch electrodes through a second one of the touch wires, outputting an output The signal indicates the presence or absence of the touch of the display panel, wherein the supply of the touch drive signal to the touch electrodes and the application of the data voltages to the data lines are in at least one active time in a frame time Simultaneous execution, where the frame time includes one or more active time and one or more blank time. According to the touch control circuit of claim 14, the differential amplifier is used for outputting the output signal during the display driving period. The touch circuit according to claim 14, further comprising: A first preamplifier for receiving the first sensing signal through the first touch line and outputting a first input signal to the differential amplifier; and a second preamplifier for transmitting through the second The touch wire receives the second sensing signal and outputs a second input signal to the differential amplifier. The touch circuit according to claim 16, wherein the first preamplifier includes: a first non-inverting input terminal to receive the touch drive signal; and a first inverting input terminal to output the touch Driving signal to the first touch line and receiving the first sensing signal from the first touch line; and a first output terminal for outputting the first input signal to the differential amplifier, and the second The preamplifier includes: a second non-inverting input terminal to receive the touch drive signal; a second inverting input terminal to output the touch drive signal to the second touch line and from the second touch The control line receives the second sensing signal; and a second output terminal for outputting the second input signal to the differential amplifier. The touch circuit according to claim 17, further comprising: a first feedback capacitor electrically connected to the first inverting input terminal of the first preamplifier and the first output of the first preamplifier Between the terminals and a second feedback capacitor is electrically connected between the second inverting input terminal of the second preamplifier and the second output terminal of the second preamplifier. The touch circuit according to claim 17, further comprising: a first resistor electrically connected to the first inverting input terminal of the first preamplifier and the first output of the first preamplifier Between terminals, and A second resistor is electrically connected between the second inverting input terminal of the second preamplifier and the second output terminal of the second preamplifier. The touch circuit according to claim 14, further comprising: a multiplexer circuit, the first touch line and the second touch line selected from the touch lines are used for differential sensing, and The selected first touch line and the second touch line are electrically connected to the differential amplifier. A touch sensing method for a touch display device. The touch display device includes a display panel. The display panel includes a plurality of data lines, a plurality of gate lines, a plurality of touch electrodes, and electrical contact with the touch electrodes. A plurality of touch lines connected, the touch sensing method includes: during a display driving period of the touch display device in which a plurality of data voltages are applied to the data lines to display an image, by the touch Supply a touch drive signal to the touch electrodes; receive a first sensing signal from one of the first touch electrodes of the touch electrodes through one of the first touch wires of the touch wires; One of the equal touch lines, the second touch line receives a second sensing signal from one of the second touch electrodes of the touch electrodes; based on a difference between the first sensing signal and the second sensing signal Value, an output signal is generated; and the presence or absence of touch of the touch display device is detected based on the output signal, wherein the touch driving signal is supplied to the touch electrodes and the data voltage is applied to the data The line is executed simultaneously in at least one activity time in a frame time, where the frame time includes one or more activity times and one or more blank times. The touch sensing method according to claim 21, wherein the presence or absence of touch is detected during the display driving period.

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