KR102430780B1 - Touch display device, touch circuit, and touch sensing method - Google Patents

Abstract

Embodiments of the present invention relate to a touch display device, a touch circuit, and a touch sensing method, and more particularly, by performing differential sensing on the touch electrodes, the touch electrodes may be connected to the display electrodes (eg, a data line, a gate line). etc.), so that the touch can be accurately sensed by removing the noise component, so that the display driving and the touch sensing can be normally performed at the same time. As described above, as display driving and touch sensing can be normally performed simultaneously, a high-resolution display may be realized.

Description

TOUCH DISPLAY DEVICE, TOUCH CIRCUIT, AND TOUCH SENSING METHOD

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

As the information society develops, the demand for a touch display device for displaying an image is increasing in various forms, and in recent years, various display devices such as a liquid crystal display device, a plasma display device, an organic light emitting display device, etc. are utilized.

Among these display devices, there is a touch display device that provides a touch-based input method that allows a user to easily and intuitively and conveniently input information or a command by breaking away from a conventional input method such as a button, a keyboard, and a mouse.

Since such a touch display device has to provide both an image display function and a touch sensing function, a driving time such as a frame time is divided into a display driving period and a touch driving period, a display driving is performed in the display driving period, and a display driving period is performed. Touch driving and touch sensing are performed in the subsequent touch driving period.

In the case of the above-described time division driving method, in order to time division display driving and touch driving, very precise timing control is required, and expensive parts may be required for this.

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

Against this background, an object of the embodiments of the present invention is to provide a touch display device capable of simultaneously performing display driving and touch driving, a touch circuit, and a touch sensing method.

Another object of the embodiments of the present invention is to provide a touch display device, a touch circuit, and a touch sensing method for preventing touch sensitivity from being affected by display driving.

Another object of the embodiments of the present invention is to provide a display device, a touch circuit, and a touch sensing method that enable the realization of a high-resolution display.

Another object of the embodiments of the present invention is to provide a touch display device capable of performing touch sensing without being affected by data driving, a touch circuit, and a touch sensing method.

Another object of the embodiments of the present invention is to provide a touch display device, a touch circuit, and a touch sensing method capable of sensing a touch while maximally securing a display driving time and sufficiently securing a pixel charging time.

Embodiments of the present invention include a display panel in which a plurality of data lines and a plurality of gate lines are disposed, a plurality of touch electrodes are disposed, and a plurality of touch lines electrically connected to correspond to the plurality of touch electrodes are disposed; , It is possible to provide a touch display device including a touch circuit for detecting the presence or absence of a touch or touch coordinates based on sensing signals received from corresponding two or more touch electrodes through two or more touch lines among a plurality of touch lines.

In such a touch display device, the touch circuit includes a first sensing signal received from the first touch electrode through a first touch line among the plurality of touch lines during a display driving period in which data voltages are applied to the plurality of data lines; A differential amplifier for outputting an output signal corresponding to a difference between a second sensing signal received from a second touch electrode through a second touch line among a plurality of touch lines, and integrating the output signal or the signal processed by the output signal It may include an integrator that outputs.

The touch circuit includes a first preamplifier that receives a first sensing signal through a first touch line among the plurality of touch lines and outputs the first input signal to the differential amplifier, and a second touch line of the plurality of touch lines. It may further include a second preamplifier receiving the second sensing signal through the input and outputting the second input signal to the differential amplifier.

The touch circuit may further include a first amplifier connected between the first pre-amplifier and the differential amplifier, and a second amplifier connected between the second pre-amplifier and the differential amplifier.

The touch circuit may further include an amplifier coupled between the differential amplifier and the integrator.

The touch circuit may select the first touch line (or first touch electrode) and the second touch line (or second touch electrode) for differential sensing from among a plurality of touch lines and electrically connect them to the differential amplifier. .

The multiplexer circuit may receive two control signals and select a first touch line and a second touch line for differential sensing.

In the touch display device, a plurality of touch lines and a plurality of data lines may be disposed in the same direction.

Embodiments of the present invention provide a display panel in which a plurality of data lines and a plurality of gate lines are disposed, a plurality of touch electrodes are disposed, and a plurality of touch lines electrically connected to the plurality of touch electrodes are disposed. A touch circuit for driving may be provided.

The touch circuit includes a first sensing signal received from a first touch electrode through a first touch line among a plurality of touch lines and a plurality of touch lines during a display driving period in which data voltages are applied to the plurality of data lines. a differential amplifier for outputting an output signal corresponding to a difference between the second sensing signal received from the second touch electrode through the second touch line, and an integrator for outputting the output signal or the signal-processed signal by integrating the output signal can do.

The touch driving signal may be a signal whose voltage level changes.

The touch driving signal may be a voltage corresponding to a ground voltage at which the display panel is grounded.

Embodiments of the present invention include a display panel in which a plurality of data lines and a plurality of gate lines are disposed, a plurality of touch electrodes are disposed, and a plurality of touch lines electrically connected to correspond to the plurality of touch electrodes are disposed; , a value corresponding to a difference between the first sensing signal and the second sensing signal received from the first touch line and the second touch line among the plurality of touch lines during a display driving period in which data voltages are applied to the plurality of data lines It is possible to provide a touch display device including a touch circuit for obtaining touch presence or touch coordinates based on sensing data including

Embodiments of the present invention provide a display panel in which a plurality of data lines and a plurality of gate lines are disposed, a plurality of touch electrodes are disposed, and a plurality of touch lines electrically connected to the plurality of touch electrodes are disposed. It is possible to provide a method for sensing a touch of a touch display device including:

In this touch sensing method, during a display driving period in which data voltages are applied to a plurality of data lines, a first sensing signal is received from a first touch electrode through a first touch line among a plurality of touch lines, and a plurality of touch lines are applied. Receiving a second sensing signal from a second touch electrode through a second touch line among the lines, generating an output signal corresponding to a difference between the first sensing signal and the second sensing signal, and based on the output signal It may include obtaining touch presence or touch coordinates.

According to the above-described embodiments of the present invention, it is possible to provide a touch display device, a touch circuit, and a touch sensing method capable of simultaneously performing display driving and touch driving.

In addition, according to embodiments of the present invention, it is possible to provide a touch display device, a touch circuit, and a touch sensing method for preventing touch sensitivity from being affected by display driving.

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

Further, according to embodiments of the present invention, it is possible to provide a touch display device, a touch circuit, and a touch sensing method capable of performing touch sensing without being affected by data driving.

In addition, according to embodiments of the present invention, it is possible to provide a touch display device, a touch circuit, and a touch sensing method capable of sensing a touch while securing a display driving time as much as possible and sufficiently securing a pixel charging time.

1 and 2 are system configuration diagrams of a touch display device according to embodiments of the present invention.
3 is a diagram illustrating a display panel having a built-in touch screen panel in a touch display device according to embodiments of the present invention.
4 is a diagram illustrating time division driving of a touch display device according to embodiments of the present invention.
5 is a diagram illustrating time-free driving of a touch display device according to embodiments of the present invention.
6 is a diagram schematically illustrating a single sensing type touch driving circuit of a touch display device according to embodiments of the present invention.
7 to 10 are diagrams illustrating a touch driving circuit of a differential sensing method of a touch display device according to embodiments of the present invention.
11A and 11B are examples of two touch electrodes that are differentially sensed in a touch display device according to embodiments of the present invention.
12A and 12B are diagrams for explaining ground voltage modulation for time-free driving in a touch display device according to embodiments of the present invention.
13 is a graph for explaining a touch sensing effect according to a differential sensing method of a touch display device according to embodiments of the present invention.
14 is a flowchart of a touch sensing method of a touch display device according to embodiments of the present invention.
15 is another exemplary diagram illustrating a differential sensing type touch driving circuit having a voltage sensing structure according to embodiments of the present invention.
16 is a diagram illustrating an output of an integrator in a differential sensing type touch driving circuit having a voltage sensing structure according to embodiments of the present invention.
17 is a diagram illustrating a data voltage, a touch driving signal, and an output signal of a differential amplifier when using a differential sensing type touch driving circuit having a voltage sensing structure according to embodiments of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to components of each drawing, the same components may have the same reference numerals as much as possible even though they are indicated in different drawings. In addition, in describing the present invention, when it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description may be omitted.

In addition, in describing the components of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, order, or number of the elements are not limited by the terms. When it is described that a component is “connected”, “coupled” or “connected” to another component, the component may be directly connected or connected to the other component, but other components may be interposed between each component. It should be understood that each component may be “interposed” or “connected,” “coupled,” or “connected” through another component.

1 and 2 are system configuration diagrams of a touch display device according to embodiments of the present invention.

The touch display apparatus according to the embodiments may perform an image display function and a touch sensing function (touch input function).

Hereinafter, configurations for the touch display device according to the embodiments to provide an image display function will be described with reference to FIG. 1 , and for the touch display device according to the embodiments to provide a touch sensing function (touch input function) Configurations will be described with reference to FIG. 2 .

Referring to FIG. 1 , in the touch display device according to the embodiments, a plurality of data lines DL and a plurality of gate lines GL are disposed to provide an image display function, and the plurality of data lines The display panel DISP in which a plurality of sub-pixels SP defined by the DL and the plurality of gate lines GL are arranged, and a source driving circuit SDC for driving the plurality of data lines DL ), a gate driving circuit GDC for driving the plurality of gate lines GL, a timing controller TCON for controlling the source driving circuit SDC and the gate driving circuit GDC, and the like.

A pixel electrode in each subpixel SP may be disposed in the display panel DISP.

A pixel voltage may be applied to the pixel electrode of each subpixel SP.

Also, one or two or more common electrodes to which a common voltage is applied may be disposed on the display panel DISP.

One common electrode is one cylindrical electrode formed on the front surface of the display panel DISP.

The two or more common electrodes may be regarded as an electrode obtained by dividing one tubular electrode into two or more. Each of the two or more common electrodes may have a size larger than the size of one subpixel area.

In each subpixel SP, a corresponding electric field may be 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 driving control signals DCS and GCS to the source driving circuit SDC and the gate driving circuit GDC to control the source driving circuit SDC and the gate driving circuit GDC. .

The timing controller (TCON) starts scanning according to the timing implemented in each frame, and converts the input image data input from the outside to match the data signal format used by the source driving circuit (SDC) to convert the converted image data ( Data) and control the data drive at an appropriate time according to the scan.

The above-described timing controller TCON includes, along with input image data, a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, an input data enable (DE) signal, a clock signal CLK, and the like. It receives various timing signals from the outside (eg, host system).

The timing controller TCON converts the input image data input from the outside to match the data signal format used by the source driving circuit SDC and outputs the converted image data, as well as driving the source driving circuit SDC and the gate In order to control the circuit GDC, a timing signal such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, an input DE signal, and a clock signal is received, and various driving control signals are generated to generate a source driving circuit SDC. and the gate driving circuit GDC.

For example, the timing controller TCON may include a gate start pulse (GSP), a gate shift clock (GSC), and a gate output enable signal (GSP) to control the gate driving circuit (GDC). Various gate driving control signals GCS including gate output enable (GOE) and the like may be output.

In addition, the timing controller TCON includes a source start pulse (SSP), a source sampling clock (SSC), and a source output enable signal (SOE) to control the source driving circuit SDC. Source Output Enable) and the like may output various data driving control signals DCS.

The timing controller TCON may be a control device that further performs other control functions including the timing controller.

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

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

The source driving circuit SDC may be implemented by including at least one source driver integrated circuit (SDIC).

Each source driver integrated circuit SDIC may include a shift register, a latch circuit, a digital to analog converter (DAC), an output buffer, and the like.

Each source driver integrated circuit SDIC may further include an analog-to-digital converter (ADC) in some cases.

Each source driver integrated circuit SDIC is connected to a bonding pad of the display panel DISP by a tape automated bonding (TAB) method or a chip on glass (COG) method, or , may be directly disposed on the display panel DISP, or may be integrated and disposed on the display panel DISP in some cases. In addition, each source driver integrated circuit SDIC may be implemented in a Chip On Film (COF) method mounted on a film connected to the display panel DISP.

The gate driving circuit GDC sequentially drives the plurality of gate lines GL by sequentially supplying a scan signal to the plurality of gate lines GL. Here, the gate driving circuit GDC is also referred to as a scan driving circuit.

The gate driving circuit GDC may be implemented by including at least one gate driver integrated circuit (GDIC).

Each gate driving circuit integrated circuit GDIC may include a shift register, a level shifter, and the like.

Each gate driver integrated circuit GDIC is connected to a bonding pad of the display panel DISP by a tape automated bonding (TAB) method or a chip-on-glass (COG) method, or a gate in panel (GIP) type. , and may be directly disposed on the display panel DISP, or may be integrated and disposed on the display panel DISP in some cases. In addition, each gate driver integrated circuit GDIC may be implemented in a chip-on-film (COF) method that is mounted on a film connected to the display panel DISP.

The gate driving circuit GDC sequentially supplies a scan signal of an on voltage or an off voltage to the plurality of gate lines GL under the control of the timing controller TCON.

When a specific gate line is opened by the gate driving circuit GDC, the source driving circuit SDC converts the image data DATA received from the timing controller TCON into an analog data voltage to generate a plurality of data lines ( DL).

The source driving circuit SDC may be located only on one side (eg, upper or lower side) of the display panel DISP, and in some cases, both sides of the display panel DISP (eg, according to a driving method, a panel design method, etc.) : It may be located on both the upper and lower side).

The gate driving circuit GDC may be located only on one side (eg, left or right) of the display panel DISP, and in some cases, both sides (eg, left or right side) of the display panel DISP according to a driving method, a panel design method, etc. For example, it can be located on both the left and right side).

Referring to FIG. 2 , a touch display device according to embodiments provides a touch sensing function, a touch screen panel TSP, and a touch circuit TC for sensing a touch using the touch screen panel TSP. ) may be included.

The touch circuit TC may include a touch driving circuit TDC, a micro control unit (MCU), and the like.

The touch driving circuit (TDC) and the micro control unit (MCU) may be implemented separately or may be integrated and implemented as one.

A plurality of touch electrodes TE and a plurality of touch lines TL electrically connected to the plurality of touch electrodes TE may be disposed on the touch screen panel TSP.

One touch electrode TE may be a tubular electrode, an electrode having several holes, a mesh electrode, or a comb-shaped electrode.

One touch electrode TE may be electrically connected to one or more touch lines TL through one or more contact holes.

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

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

For example, the touch driving circuit TDC supplies a touch driving signal to all or a part of the plurality of touch electrodes TE disposed on the touch screen panel TSP, and receives a signal from at least one touch electrode TE. It can be detected to generate and output sensing data.

The touch driving circuit TDC may supply a touch driving signal to one or more touch electrodes TE through one or more touch lines TL and detect a touch sensing signal.

The micro control unit MCU may acquire touch presence and/or touch coordinates using sensing data output from the touch driving circuit TDC.

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

When sensing a touch based on mutual-capacitance, the touch electrodes TE on the touch screen panel TSP may be arranged in a matrix form. In this case, each touch electrode TE may have a bar shape.

Alternatively, when sensing a touch based on mutual-capacitance, the touch electrodes TE on the panel TSP may form row-direction touch electrode lines and column-direction touch electrode lines. In this case, the touch electrodes TE may have a diamond shape.

The touch driving circuit TDC supplies a touch driving signal to the touch electrodes TE or touch electrode lines in the row direction (or column direction), and the touch electrodes TE or the touch electrodes TE in the column direction (or row direction) or A touch sensing signal is received through the touch electrode lines, and sensing data is generated based on the received touch sensing signal and supplied to the microcontroller unit (MCU). The micro control unit (MCU) senses touch presence or touch coordinates based on the sensed data.

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

The touch driving circuit TDC supplies a touch driving signal to all or part of the plurality of touch electrodes TE, receives a touch sensing signal from the touch electrodes TE to which the touch driving signal is supplied, and receives the received touch. Based on the sensing signal, sensing data is generated and supplied to the microcontroller unit (MCU). The micro control unit (MCU) senses touch presence or touch coordinates based on the sensed data.

As described above, the touch display apparatus according to embodiments of the present invention may sense a touch based on self-capacitance or may sense a touch based on mutual-capacitance. However, hereinafter, for convenience of description, sensing a touch based on self-capacitance will be described as an example.

The touch screen panel TSP may be manufactured separately from the display panel DISP and bonded to the display panel DISP, or may be embedded in the display panel DISP.

When the touch screen panel TSP is embedded in the display panel DISP, the touch screen panel TSP may be viewed as an aggregate 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 may be integrated and implemented.

3 is a diagram illustrating a display panel DISP having a built-in touch screen panel TSP in a touch display device according to embodiments of the present invention.

When the touch screen panel TSP is embedded in the display panel DISP, the plurality of touch electrodes TE disposed on the display panel DISP may be a common electrode used when driving the display. In this case, as an example, the display panel DISP may be a liquid crystal display panel.

Accordingly, a common voltage may be applied to the plurality of touch electrodes TE for image display, and a touch driving signal may be 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 disposed on the entire surface of the display panel DISP and on an encapsulation layer disposed on the common electrode to which a common voltage is applied. can be located

Here, the common electrode disposed on the front surface of the display panel DISP, which is an organic light emitting display panel, is, for example, an anode electrode (corresponding to a pixel electrode) of an organic light emitting diode (OLED) in each subpixel SP. ) and the cathode electrode may be the cathode electrode, and the common voltage may be the cathode voltage.

In this case, each of the plurality of touch electrodes TE may have a tubular electrode shape without an open area. In this case, each of the plurality of touch electrodes TE may be a transparent electrode for light emission from the sub-pixels SP.

Alternatively, each of the plurality of touch electrodes TE may be a mesh-type electrode having a plurality of open regions. In this case, in each of the plurality of touch electrodes TE, each open area may correspond to a light emitting area (eg, a region in which a part of the anode electrode is located) of the subpixel SP.

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

That is, an area size of one touch electrode TE may correspond to an area size of two or more sub-pixels SP.

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

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

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

2 and 3 , the plurality of touch lines TL may be arranged in the same direction as the plurality of data lines DL.

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

Alternatively, the plurality of touch lines TL may be arranged in the same direction as the plurality of gate lines GL.

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

4 is a diagram illustrating time division driving of a touch display device according to embodiments of the present invention, and FIG. 5 is a diagram illustrating time-free driving of a touch display device according to embodiments of the present invention.

Hereinafter, it is assumed that the plurality of touch electrodes TE serve as a common electrode for driving the display.

The touch display apparatus according to embodiments of the present invention may perform a driving operation in a time division driving method and/or a time free driving method.

Referring to FIG. 4 , the touch display device according to embodiments of the present invention provides a display driving function for providing an image display function and a touch sensing function when a driving operation is performed in a time division driving method. The touch driving for this purpose may be performed in the time-divided display driving period and the touch driving period, respectively.

Timing of the display driving period and the touch driving period may be controlled by the touch synchronization signal TSYNC.

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

Here, the common voltage may be a pixel voltage applied to a pixel electrode in each sub-pixel and a voltage forming an electric field.

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

In this case, the touch driving signal TDS or a signal corresponding thereto may be applied to all or part of the data lines DL. The touch driving signal TDS or a signal corresponding thereto may be further applied to all or part of the gate lines GL.

The touch driving signal TDS may be a signal with a variable voltage level.

The touch driving signal TDS may also be referred to as an AC signal, a modulated signal, or a pulse signal.

Referring to FIG. 5 , the touch display device according to embodiments of the present invention provides a display driving function for providing an image display function and a touch sensing function when a driving operation is performed in a time free driving method. touch driving can be performed at the same time. This time-free driving method is also referred to as a simultaneous driving method.

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

When the touch display device according to the exemplary embodiments performs a driving operation in a time-free driving method, the data voltage VDATA is supplied to the data line DL during the active time in every frame time, in this case , the touch driving signal TDS may be supplied to the plurality of touch electrodes TE.

The touch driving signal TDS may be a signal for driving the touch electrodes TE for touch sensing and may be a common voltage allowing the touch electrodes TE to serve as a common electrode for driving a display.

When the touch display device according to the embodiments of the present invention operates in a time-free driving method, the pixel voltage applied to the pixel electrode in each sub-pixel and the common voltage forming the electric field are the DC voltage Instead, it may be a signal whose voltage level is variable.

This common voltage may also be referred to as an AC signal or a modulated signal or a pulsed signal.

When the touch display device according to the embodiments of the present invention performs a driving operation in a time free driving method, the plurality of touch electrodes TE may be a plurality of blocked common electrodes, and the touch driving signal (TDS) can also be viewed as a common voltage.

On the other hand, the touch display device according to the embodiments of the present invention may always perform a driving operation in a time division driving method, or may always perform a driving operation in a time free driving method, The driving operation may be performed using both the time division driving method and the time free driving method.

6 is a diagram schematically illustrating a single sensing type touch driving circuit (TDC) of a touch display device according to embodiments of the present invention.

Referring to FIG. 6 , the touch display device according to embodiments of the present invention may sequentially or simultaneously drive a plurality of touch electrodes TE, and separate each touch electrode TE for sensing.

As described above, a method of separating and sensing each touch electrode TE is referred to as a single sensing method or a single ended method.

The first touch electrode TE1 and the second touch electrode TE2 overlapping one display electrode (eg, a data line, a gate line) in the display panel DISP are a first touch line TL1 and a second touch electrode TE2. It may be electrically connected to the touch driving circuit TDC through the touch line TL2 .

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

The touch driving circuit TDC is a sensing unit for the first touch electrode TE1 and includes a first preamplifier P-AMP1 that receives the first sensing signal TSS1 through the first touch line TL1 and , an amplifier (A-APM1) for amplifying the signal output from the first preamplifier (P-AMP1), and a first integrator (INTG1) for integrating the signal output from the amplifier (A-AMP1). have.

The touch driving circuit TDC is a sensing unit for the second touch electrode TE2 and includes a second preamplifier P-AMP2 that receives the second sensing signal TSS2 through the twelfth touch line TL2 and , an amplifier (A-APM2) for amplifying the signal output from the second preamplifier (P-AMP2), and a second integrator (INTG2) for integrating the signal output from the amplifier (A-AMP2). have.

The first preamplifier P-AMP1 includes a non-inverting input terminal receiving the touch driving signal TDS, and outputting the touch driving signal TDS to the first touch line TL1 and receiving the touch driving signal TDS from the first touch line TL1 . It may include an inverted input terminal receiving the first sensing signal TSS1 and an output terminal outputting the first sensing signal TSS1 or a signal corresponding thereto.

A feedback capacitor Cfb1 may be 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 receiving the touch driving signal TDS, and outputting the touch driving signal TDS to the second touch line TL2 and receiving the touch driving signal TDS from the second touch line TL2. It may include an inverted input terminal receiving the second sensing signal TSS2 and an output terminal outputting the second sensing signal TSS2 or a signal corresponding thereto.

A feedback capacitor Cfb2 may be connected between an inverting input terminal and an output terminal of the second preamplifier P-AMP2.

The above-described sensing unit for the first touch electrode TE1 and the sensing unit for the second touch electrode TE2 may be different sensing units.

Alternatively, when sensing the first touch electrode TE1 and the second touch electrode TE2 at different times, the sensing unit for the first touch electrode TE1 and the sensing unit for the second touch electrode TE2 are It may be the same sensing unit.

As described above, in the case of the single sensing method, the voltage fluctuation of the display electrode affects the touch sensing signal TSS due to coupling between the display electrode such as the data line DL and the touch electrode TE. Accordingly, a touch sensing malfunction may occur, and the touch sensitivity may be greatly reduced.

As illustrated in FIG. 4 , when the touch display device according to the embodiments of the present invention operates in a time division manner, when a voltage change in the display electrode such as the data line DL does not occur, the touch As the driving and sensing operations are performed, the coupling effect between the display electrode such as the data line DL and the touch electrode TE may be minimized.

However, when the touch display device according to the embodiments of the present invention operates in the time division driving method, since time for touch driving and sensing must be separately allocated within one frame time, the display driving time may be insufficient. .

In particular, when the touch display device according to the embodiments of the present invention is applied to a high-resolution display, the display driving time that can satisfy the high-resolution display may be considerably insufficient, and it is difficult to secure sufficient pixel charging time in units of pixels. There are disadvantages.

Therefore, there is an urgent need for a method capable of minimizing the coupling effect between the display electrode such as the data line DL and the touch electrode TE while performing the driving operation in a time-free driving method to enable a high-resolution display. to be.

Hereinafter, a method of minimizing the coupling effect between the display electrode such as the data line DL and the touch electrode TE while performing the driving operation in a time-free driving method to enable a high-resolution display will be described. do.

7 to 10 are diagrams illustrating a touch driving circuit of a differential sensing method of a touch display device according to embodiments of the present invention.

A touch display device according to embodiments of the present invention includes a display panel DISP having a built-in touch screen panel TSP, and a touch circuit TC for sensing a touch while an image is displayed through the display panel DISP. ) and the like.

A plurality of data lines DL and a plurality of gate lines GL are disposed in the display panel DISP in which the touch screen panel TSP is embedded, a plurality of touch electrodes TE are disposed, and a plurality of A plurality of touch lines TL electrically connected to the touch electrodes TE may be disposed.

The touch circuit TC may drive the touch electrodes TE in a time free driving method and sense the touch electrodes TE in a differential sensing method.

That is, the touch circuit TC includes a first touch line TL1 and a second touch line TL1 among the plurality of touch lines TL during a display driving period in which the data voltages VDATA are applied to the plurality of data lines DL. A touch presence or touch coordinates may be acquired based on sensing data including a value corresponding to a difference between the first sensing signal TSS1 and the second sensing signal TSS2 received from the touch line TL2 .

As described above, touch sensing may be performed by removing a noise component generated from the two touch electrodes TE1 and TE2 by the display electrode. That is, it is possible to remove the influence of touch driving and sensing by driving the display. Through this, time-free driving in which display driving and touch driving are performed at the same time can be normally performed. Accordingly, the display driving time can be secured as much as possible and the pixel charging time can be sufficiently secured, so that a high-resolution display can be realized.

Below, the touch driving circuit in the touch circuit TC that drives the touch electrodes TE in a time free driving method and senses the touch electrodes TE in a differential sensing method ( TDC) will be described in more detail with reference to FIGS. 7 to 10 .

7 to 10 are diagrams illustrating a differential sensing type touch driving circuit (TDC) of a touch display device according to embodiments of the present invention.

7 to 10 , the touch driving circuit TDC in the touch circuit TC includes two or more touch electrodes corresponding to each other through two or more touch lines TL1 and TL2 among the plurality of touch lines TL. Two or more sensing signals TSS1 and TSS2 may be received from (TE1, TE2).

7 to 10 , the touch driving circuit TDC in the touch circuit TC is electrically connected to the first touch line TL1 and the second touch line TL2 among the plurality of touch lines TL. It may include a differential amplifier (D-AMP) and the like.

Referring to FIGS. 7 to 10 , for example, the differential amplifier D-AMP may use a plurality of touch lines ( TL) through the first sensing signal TSS1 received from the first touch electrode TE1 through the first touch line TL1 and the second touch line TL2 among the plurality of touch lines TL An output signal proportional to a difference between the second sensing signal TSS2 received from the touch electrode TE2 may be output.

7 to 10 , in the touch driving circuit TDC in the touch circuit TC, the output signal output from the differential amplifier D-AMP or a signal processed by the output signal (eg, the output signal is amplified) signal) may further include an integrator (INTG) to integrate and output.

Here, the integral value output from the integrator INTG may be a value proportional to “TSS1-TSS2” or a value proportional to “TSS2-TSS1”.

As described above, by differentially sensing the two touch electrodes TE1 and TE2, the two touch electrodes TE1 and TE2 remove a noise component received from the display electrodes (eg, data line, gate line, etc.) for touch sensing. can do. That is, it is possible to remove the influence of touch driving and sensing by driving the display. Through this, time-free driving in which display driving and touch driving are performed at the same time can be normally performed. Accordingly, the display driving time can be secured as much as possible and the pixel charging time can be sufficiently secured, so that a high-resolution display can be realized.

7 to 10 , the touch driving circuit TDC in the touch circuit TC provides a touch driving signal TDS to the first touch electrode TE1 and the second touch electrode TE2 during the display driving period. may be supplied, and the first sensing signal TSS1 and the second sensing signal TSS2 may be received from the first touch electrode TE1 and the second touch electrode TE2 .

That is, during the display driving period, a touch may be sensed using a differential sensing method based on self-capacitance.

The touch driving circuit TDC may further include an analog-to-digital converter (not shown) that converts the integral value output by the integrator INTG into a digital sensing value.

The touch driving circuit TDC outputs sensed data including the digital sensed value generated by the analog-to-digital converter.

The touch circuit TC includes a touch driving circuit TDC that outputs sensing data including values corresponding to differences in sensing signals corresponding to two touch electrodes during a display driving period, and a touch driving circuit during a display driving period. It may include a micro control unit (MCU) that detects the presence or absence of a touch or touch coordinates based on the sensed data output from the circuit TDC.

As described above, in the touch display device according to the embodiments of the present invention, the touch driving circuit (TDC) and the micro control unit (MCU) constituting the touch circuit (TC) are used to drive the touch during the display driving period. and touch sensing processing.

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

In this case, 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 data voltage VDATA supplied to each of the two or more subpixels SP overlapping each touch electrode TE and a common voltage forming a capacitance.

That is, during the display driving period, the touch driving signal TDS is a voltage forming capacitance with the data voltage VDATA supplied to each of the two or more subpixels SP overlapping the first touch electrode TE1, and It may be a data voltage VDATA supplied to each of the two or more subpixels SP overlapping the second touch electrode TE2 and a voltage forming a capacitance.

During the display driving period, the touch driving signal TDS supplied to the plurality of touch electrodes TE may be a signal whose voltage level changes for touch driving.

When the touch display device according to embodiments of the present invention performs a driving operation in a time-free driving method, the plurality of touch electrodes TE are common electrodes, and the touch driving signal TDS is a common voltage, display driving During the period, the common voltage supplied to the common electrode may be viewed as a signal whose voltage level changes.

As described above, the touch driving signal TDS may be used as a common voltage for driving the display. DISP) can be efficiently driven in a time-free driving method.

7 to 10 , the touch driving circuit TDC in the touch circuit TC inputs the first sensing signal TSS1 through the first touch line TL1 among the plurality of touch lines TL. The first preamplifier P-AMP1 receiving the first input signal IN1 and outputting the first input signal IN1 to the differential amplifier D-AMP, and the second touch line TL2 among the plurality of touch lines TL A second preamplifier P-AMP2 may be further included to receive the sensing signal TSS2 and output the second input signal IN2 to the differential amplifier D-AMP.

As described above, by placing the first pre-amplifier (P-AMP1) and the second pre-amplifier (P-AMP2) in front of the signal detection configuration (eg, analog-to-digital converter), attenuation of the signal and the signal due to noise It is possible to prevent a signal to noise ratio (SNR) from being lowered, and through this, it is possible to more accurately detect a signal from each of the first touch electrode TE1 and the second touch electrode TE2 .

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 the first sensing signal TSS1 from the first touch line TL1 receive input.

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

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 the second sensing signal TSS2 from the second touch line TL2. receive input.

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 may be electrically connected to each other.

Accordingly, the touch driving signal TDS is simultaneously transmitted to the first non-inverting input terminal A1 of the first pre-amplifier P-AMP1 and the second non-inverting input terminal A2 of the second pre-amplifier P-AMP2 at the same time. is input

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.

Accordingly, the touch driving signal TDS is applied to the first touch electrode TE1 through the first touch line TL1 and is simultaneously applied to the second touch electrode TE2 through the second touch line TL2 . can be

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

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

As described above, by using the first pre-amplifier (P-AMP1) and the second pre-amplifier (P-AMP2), in order to sense a touch based on self-capacitance, a driving signal supply for touch driving and touch sensing It is possible to efficiently perform sensing signal detection for

Referring to FIG. 8 , the touch driving circuit TDC in the touch circuit TC may further include an amplifier A-AMP connected between the differential amplifier D-AMP and the integrator INTG.

By utilizing this additional amplifier (A-AMP), it is possible to amplify the signal output from the differential amplifier (D-AMP) to perform integration processing. Accordingly, it is possible to obtain a larger (higher) touch sensing value, thereby increasing the touch sensitivity.

Referring to FIG. 9 , the touch driving circuit TDC in the touch circuit TC includes a first amplifier AMP1 connected between a first preamplifier P-AMP1 and a differential amplifier D-AMP, and a second A second amplifier AMP2 connected between the preamplifier P-AMP2 and the differential amplifier D-AMP may be further included.

By further utilizing 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 may be amplified. Accordingly, the signal output to the differential amplifier (D-AMP) can be increased, and a larger (higher) touch sensing value can be obtained, thereby increasing the touch sensitivity.

Referring to FIG. 10 , the touch driving circuit TDC performs differential sensing according to two control signals Q1 and Q2 input from a micro control unit (MCU), a timing controller (TCON), an internal control unit, or another control device. It may further include a multiplexer circuit MUX for selecting two touch electrodes TE1 and TE2 for , and connecting them to the differential amplifier D-AMP. Here, each of the two control signals Q1 and Q2 may be a control signal corresponding to the two touch electrodes TE1 and TE2 or the two touch lines TL1 and TL2.

In FIG. 10 , an enlarged portion of the multiplexer circuit MUX is illustrated by omitting circuit configurations between the multiplexer circuit MUX and the differential amplifier D-AMP.

Accordingly, by the multiplexer circuit MUX, the first pre-amplifier (P-AMP1) and the second pre-amplifier (P-AMP2), for signal detection for differential sensing, two control signals Q1, Q2 ) may selectively be electrically connected to the first touch line TL1 and the second touch line TL2 .

According to the above-described multiplexer circuit MUX, many touch electrodes TE can be sensed with only a small number of differential sensing units (such as first and second preamplifiers, differential amplifiers, and integrators). One such multiplexer circuit MUX may exist for every one touch electrode column including two or more touch electrodes TE, or one for every two or more touch electrode columns.

When the differential sensing method for the two touch electrodes TE1 and TE2 described above is expanded and exemplarily described, assuming that eight touch electrodes TE1 to TE8 exist in one touch electrode column, the first In the signal detection section, a differential sensing operation between TE1 and TE2, a differential sensing operation between TE3 and TE4, a differential sensing operation between TE5 and TE6, and a differential sensing operation between TE7 and TE8 may be performed. In the second signal detection period, a differential sensing operation between TE2 and TE3, a differential sensing operation between TE4 and TE5, and a differential sensing operation between TE6 and TE7 may be performed. As another example of the above-described differential sensing sequence, a differential sensing operation between TE1 and TE2 (TE1-TE2), a differential sensing operation between TE2 and TE3 (TE2-TE3), and a differential sensing operation between TE3 and TE4 (TE3-TE4) This can be done sequentially. The reverse order of the differential sensing is also possible. That is, the differential sensing operation TE4-TE3 between TE4 and TE3, the differential sensing operation TE3-TE2 between TE3 and TE2, and the differential sensing operation TE2-TE1 between TE2 and TE1 may be performed.

After performing this differential sensing operation, the micro control unit (MCU) uses the differential sensing values (that is, sensing values obtained from the output signal output to the differential amplifier (D-AMP)), each of the eight touch electrodes TE1 to TE8) A sensing value corresponding to each can be calculated. For example, through an operation process of solving simultaneous equations corresponding to differential sensing values (that is, sensing values obtained from an output signal output to the differential amplifier (D-AMP)), each of the eight touch electrodes TE1 to TE8 A sensing value corresponding to can be calculated as a solution of the simultaneous equations.

11A and 11B are examples of two touch electrodes TE1 and TE2 that are differentially sensed in a touch display device according to embodiments of the present invention.

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 includes two or more data lines. It overlaps with the DLs and the two or more gate lines GL.

Referring to FIG. 11A , the first touch electrode TE1 and the second touch electrode TE2 to be differential sensing may overlap the same data line.

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

As described above, when the two touch electrodes TE1 and TE2 to be differential sensing are positioned in the data line direction, it is possible to obtain an effect of removing a noise component generated by the data line during touch sensing.

11A , when the first touch electrode TE1 and the second touch electrode TE2, which are the differential sensing targets, overlap the same data line, a first touch line electrically connected to the first touch electrode TE1 TL1 may overlap the second touch electrode TE2 in different layers and may be 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 different layers, and the first touch electrode ( DISP) in the display panel DISP. TE1) can be insulated.

Accordingly, the touch lines TL may not be disposed in the non-display area. Here, the non-display area is an outer area of the display area in which the touch electrodes TE are disposed. Accordingly, since the size of the non-display area can be reduced, there is an advantage in that the size of the bezel of the touch display device can be reduced.

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

For example, during the display driving period, the touch driving signal TDS supplied to the plurality of touch electrodes TE is constant at a time point (timing) when the voltage level of the data voltage VDATA supplied to the data line is changed. At the time-delayed time point, the voltage level may rise.

Referring to FIG. 11B , the first touch electrode TE1 and the second touch electrode TE2 to be differential sensing may overlap 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. Two or more gate lines GL overlapping the first touch electrode TE1 and two or more gate lines GL overlapping the second touch electrode TE2 may be identical to each other.

As described above, when the two touch electrodes TE1 and TE2 to be differential sensing are positioned in the gate line direction, it is possible to obtain an effect of removing a noise component generated by the gate line during touch sensing.

12A and 12B are diagrams for explaining ground voltage modulation for time-free driving in a touch display device according to embodiments of the present invention.

12A and 12B , in the touch display device according to embodiments of the present invention, the touch driving signal TDS for time-free driving corresponds to the ground voltage GND_M to which the display panel DISP is grounded. It can be voltage.

The ground voltage GND_M to which the display panel DISP is grounded may be a signal whose voltage level changes.

The touch driving signal TDS may correspond in frequency and phase to the ground voltage GND_M to which the display panel DISP is grounded.

The ground voltage GND_M to which the display panel DISP is grounded is DC to which a micro control unit (MCU) that detects the presence or absence of a touch or touch coordinates or a timing controller (TCON) for display driving control is grounded during the display driving period. It may be a signal modulated based on the ground voltage GND in the form of a voltage.

In relation to the above-described ground modulation and touch driving signal TDS, the display panel DISP is grounded to the modulated ground voltage M_GND, and thus the touch electrodes TE corresponding to the common electrodes disposed on the display panel DISP. ) is applied to the touch driving signal TDS in the form of a DC voltage, the touch driving signal TDS is shaken by the modulated ground voltage M_GND, so that the touch driving signal TDS is modulated by the modulated ground voltage M_GND. It becomes a signal whose voltage level is changed identically or similarly to .

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

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

The first ground voltage GND A, which is the DC voltage GND, is a DC voltage maintaining a constant voltage, but the second ground voltage GND B corresponding to the modulated ground voltage GND_M is DC It may be a voltage that is modulated with respect to the ground voltage GND in the form of a voltage.

That is, the voltage level of the modulated ground voltage GND_M is not maintained at a constant voltage level compared to the ground voltage GND in the form of a DC voltage, but is a voltage that is a modulation signal whose voltage level is changed as time changes. can

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

That is, it may be recognized that the touch driving signal TDS corresponding to the common voltage is modulated in which the voltage level is changed as time changes in comparison with the ground voltage GND in the form of a DC voltage.

However, when compared to the modulated ground voltage GND_M, the touch driving signal TDS corresponding to the common voltage may be recognized as a DC voltage whose voltage level does not change with time.

That is, the touch driving signal TDS corresponding to the common voltage is a signal whose voltage level changes over time when viewed from the DC voltage-type ground voltage GND side, but viewed from the modulated ground voltage GND_M side. It may be a signal having a constant voltage level without changing the voltage level over time.

On the other hand, the touch display device according to an embodiment of the present invention, based on a pulse modulated signal (eg, a pulse width modulated signal) output from the micro control unit (MCU), from the ground voltage (GND) in the form of a DC voltage A ground modulation circuit GMC for generating the modulated ground voltage GND_M may be further included.

When generating the second ground voltage GND B based on a pulse modulation signal (eg, a pulse width modulation signal), the ground modulation circuit GMC of the touch display device according to an embodiment of the present invention modulates the pulse. The second ground voltage GND B may be generated so that a signal (eg, a pulse width modulated signal) has a frequency and a phase corresponding thereto.

When generating the second ground voltage GND B based on the pulse modulated signal PWM, the ground modulating circuit GMC has a desired amplitude Vb regardless of the amplitude Va of the pulse modulated signal PWM. A second ground voltage GND B having a

The ground modulation circuit GMC of the touch display device according to an embodiment of the present invention may include 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 invention separates power for separating the first ground voltage GND in the form of a DC voltage and the second ground voltage GND_M in the form of an AC voltage can have functions.

To this end, the ground modulation circuit (GMC) may include a power separation circuit including at least one of a flyback converter, a flybuck converter, a transformer, and the like.

A plurality of touch electrodes TE disposed on the display panel DISP by grounding the second ground voltage GND B corresponding to the ground voltage GND_M modulated through the above-described ground modulation to the display panel DISP. The touch driving signal TDS applied to the may also be shaken. Accordingly, display driving and touch driving can be effectively performed simultaneously.

13 is a graph for explaining a touch sensing effect according to a differential sensing method of a touch display apparatus according to embodiments of the present invention.

In the graph shown in FIG. 13 , the X-axis is time, and the Y-axis is a voltage value output from the integrator INTG in the touch driving circuit TDC.

In the graph shown in FIG. 13 , when there is no touch, when the voltage value 1300 output from the integrator INTG is 0V, when there is a touch, the integrator INTG according to the single sensing method as in FIG. 6 . The output voltage value 1310 and the voltage value 1320 output from the integrator INTG according to the differential sensing method as shown in FIGS. 7 to 10 are shown.

Referring to FIG. 13 , the voltage value 1320 output from the integrator INTG according to the differential sensing method has a significantly higher voltage value than the voltage value 1310 output from the integrator INTG according to the single sensing method. it can be seen that

Accordingly, when the touch is sensed according to the differential sensing method, since the touch is sensed using a higher voltage value compared to the single sensing method, the touch sensitivity may be very high.

14 is a flowchart of a touch sensing method of a touch display device according to embodiments of the present invention.

Referring to FIG. 14 , in a touch sensing method of a touch display device according to embodiments of the present invention, during a display driving period in which data voltages VDATA are applied to a plurality of data lines DL, a plurality of touch lines are Receives the first sensing signal TSS1 from the first touch electrode TE1 through the first touch line TL1 of the TL, and through the second touch line TL2 among the plurality of touch lines TL Receiving the second sensing signal TSS2 from the second touch electrode TE2 ( S1210 ), and generating an output signal corresponding to a difference between the first sensing signal TSS1 and the second sensing signal TSS2 (S1220) and the step of obtaining touch presence or touch coordinates based on the output signal (S1230), and the like may be included.

Using the above-described touch sensing method, by differentially sensing the two touch electrodes TE1 and TE2, the two touch electrodes TE1 and TE2 detect noise components received from the display electrodes (eg, data lines, gate lines, etc.). It can be removed to enable touch sensing. That is, it is possible to remove the influence of touch driving and sensing by driving the display. Through this, time-free driving in which display driving and touch driving are performed at the same time can be normally performed. Accordingly, the display driving time can be secured as much as possible and the pixel charging time can be sufficiently secured, so that a high-resolution display can be realized.

As described above, the touch display device and the touch circuit TC according to the embodiments of the present invention are basically a charge sensing method for sensing a change amount of the charge between the two touch electrodes TE. It senses touch and has a charge-sensing structure (eg, a pre-amplifier with a feedback capacitor).

On the other hand, the touch display device and the touch circuit TC of the embodiments of the present invention, as well as the above-described charge sensing method and charge sensing structure, a voltage sensing method that enables sensing regardless of a change in charge flowing through a parasitic capacitance and a voltage sensing structure. Hereinafter, such a voltage sensing method and a voltage sensing structure will be described.

Here, a change in charge introduced through the parasitic capacitance may be caused by a change in a voltage state of a data line that may occur when display driving and touch driving are performed simultaneously in a time-free driving method.

15 is another exemplary diagram illustrating a differential sensing type touch driving circuit (TDC) having a voltage sensing structure according to embodiments of the present invention.

Compared with the differential sensing type touch driving circuit (TDC) having the charge sensing structure illustrated in FIGS. 6 to 11A , the differential sensing type touch driving circuit (TDC) having the voltage sensing structure illustrated in FIG. 15 . , the first and second feedback capacitors Cfb1 and Cfb2 in the first and second pre-amplifiers P-AMP1 and P-AMP2 are changed to the first and second resistors R1 and R2, and the differential There is a difference in that it has a resistor Rd connected between the input and output terminals of the amplifier D-AMP.

More specifically, the differential sensing type touch driving circuit TDC illustrated in FIGS. 6 to 11A may have 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 preamplifier A second feedback capacitor Cfb2 may be electrically connected between the second inverting input terminal B2 and the second output terminal C2 of (P-AMP2).

The differential sensing type touch driving circuit TDC illustrated in FIG. 15 may have 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 preamplifier ( A second resistor R2 may be electrically connected between the second inverting input terminal B2 and the second output terminal C2 of the P-AMP2 .

The first pre-amplifier P-AMP1 receives the first sensing signal TSS1 from the display panel DISP, and applies the input first sensing signal TSS1 to the touch driving signal ( TDS), the input first sensing signal TSS1 may be amplified to output a first voltage value to the first output terminal C1.

The second pre-amplifier P-AMP2 receives the second sensing signal TSS2 from the display panel DISP, and applies the input second sensing signal TSS2 to the touch driving signal ( TDS), the input second sensing signal TSS2 may be amplified to output a second voltage value to the second output terminal C2.

15 , according to the voltage sensing structure, in the differential amplifier (D-AMP), the first voltage value output to the first pre-amplifier (P-AMP1) or the second pre-amplifier (P-AMP2) is A resistor Rd may be electrically connected between an input terminal to which the output second voltage value is input and an output terminal to which the output signal is output.

The differential amplifier (D-AMP) compares the output signal (first voltage value) of the first pre-amplifier (P-AMP1) and the output signal (second voltage value) of the second pre-amplifier (P-AMP2) and , can be output by amplifying the difference between the two output signals.

16 is a diagram illustrating an output of an integrator (INTG) in a differential sensing type touch driving circuit (TDC) having a voltage sensing structure according to embodiments of the present invention, and FIG. It is a diagram showing the data voltage VDATA, the touch driving signal TDS, and the output signals of the differential amplifier D-AMP when the differential sensing type touch driving circuit TDC having a voltage sensing structure is used.

16 is a graph showing the output of the integrator (INTG) with respect to the case where there is no touch and the case where there is a touch by a finger.

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

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

17 illustrates a data voltage VDATA applied to a data line DL disposed on the display panel DISP, a touch driving signal TDS applied to a touch electrode TE disposed on the display panel DISP, and FIG. It is a graph showing the output signal of the differential amplifier (D-AMP) in the touch driving circuit (TDC).

As shown in FIG. 17 , when the display driving and the touch driving are simultaneously performed in the time-free driving method, even if the data voltage VDATA is fluctuated, the output signal of the differential amplifier D-AMP is the data voltage VDATA. It is hardly affected by fluctuations. Accordingly, it is possible to enable accurate touch sensing.

According to the embodiments of the present invention described above, it is possible to provide a touch display device, a touch circuit, and a touch sensing method capable of simultaneously performing display driving and touch driving.

In addition, according to embodiments of the present invention, it is possible to provide a touch display device, a touch circuit, and a touch sensing method that prevent touch sensitivity from being affected by display driving.

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

Further, according to embodiments of the present invention, it is possible to provide a touch display device, a touch circuit, and a touch sensing method capable of performing touch sensing without being affected by data driving.

In addition, according to embodiments of the present invention, it is possible to provide a touch display device, a touch circuit, and a touch sensing method capable of sensing a touch while securing a display driving time as much as possible and sufficiently securing a pixel charging time.

The above description and the accompanying drawings are merely illustrative of the technical spirit of the present invention, and those of ordinary skill in the art to which the present invention pertains can combine configurations within a range that does not depart from the essential characteristics of the present invention. , various modifications and variations such as separation, substitution and alteration will be possible. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to illustrate, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

DISP: display panel
SDC: source drive circuit
GDC: gate drive circuit
TCON: Timing Controller
TSP: touch screen panel
TDC: Touch Drive Circuit
MCU: micro control unit
TE: touch electrode
TL: touch line

Claims (31)

a display panel on which a plurality of data lines and a plurality of gate lines are disposed, a plurality of touch electrodes are disposed, and a plurality of touch lines electrically connected to the plurality of touch electrodes are disposed; and
a touch circuit for detecting the presence or absence of a touch or touch coordinates based on sensing signals received from corresponding two or more touch electrodes through two or more touch lines among the plurality of touch lines;
The touch circuit is
During a display driving period in which data voltages are applied to the plurality of data lines, a first sensing signal received from a first touch electrode through a first touch line among the plurality of touch lines and a second one of the plurality of touch lines a differential amplifier for outputting an output signal corresponding to a difference between a second sensing signal received from a second touch electrode through two touch lines;
an integrator for integrating and outputting the output signal or a signal processed by the output signal;
a first preamplifier receiving the first sensing signal through a first touch line among the plurality of touch lines and outputting a first input signal to the differential amplifier; and
a second preamplifier receiving the second sensing signal through a second touch line among the plurality of touch lines and outputting a second input signal to the differential amplifier;
The first preamplifier includes a first non-inverting input terminal to which a touch driving signal that is an AC signal, a modulated signal, or a pulse signal is input, and the second preamplifier is the AC signal, the modulated signal, or the pulse signal. a second non-inverting input terminal to which the touch driving signal is input;
A first amplifier is connected between the first pre-amplifier and the differential amplifier, and a second amplifier is connected between the second pre-amplifier and the differential amplifier.
According to claim 1,
The plurality of touch lines and the plurality of data lines are disposed in the same direction.
According to claim 1,
the first touch electrode overlaps two or more data lines and two or more gate lines;
the second touch electrode overlaps two or more data lines and two or more gate lines;
two or more data lines overlapping the first touch electrode and two or more data lines overlapping the second touch electrode are identical to each other;
The two or more gate lines overlapping the first touch electrode and the two or more gate lines overlapping the second touch electrode are different from each other.
According to claim 1,
the first touch electrode overlaps two or more data lines and two or more gate lines;
the second touch electrode overlaps two or more data lines and two or more gate lines;
two or more data lines overlapping the first touch electrode and two or more data lines overlapping the second touch electrode are different from each other;
The two or more gate lines overlapping the first touch electrode and the two or more gate lines overlapping the second touch electrode are identical to each other.
According to claim 1,
the first touch line overlaps the second touch electrode and is insulated within the display panel,
A touch display device in which the second touch line overlaps the first touch electrode and is insulated within the display panel.
According to claim 1,
The touch circuit is
a touch driving circuit for outputting sensing data including values corresponding to differences between sensing signals corresponding to two touch electrodes during the display driving period; and
The touch display device further comprising a micro control unit for detecting the presence or absence of a touch or touch coordinates based on the sensed data output from the touch driving circuit during the display driving period.
According to claim 1,
The touch circuit is
supplying the touch driving signal to the first touch electrode and the second touch electrode during the display driving period;
A touch display device configured to receive the first sensing signal and the second sensing signal from the first touch electrode and the second touch electrode.
8. The method of claim 7,
The touch driving signal is
A data voltage supplied to each of the two or more sub-pixels overlapping the first touch electrode and a voltage forming a capacitance,
A touch display device which is a data voltage supplied to each of two or more sub-pixels overlapping the second touch electrode and a voltage forming a capacitance.
8. The method of claim 7,
The touch driving signal is a voltage corresponding to a ground voltage at which the display panel is grounded.
10. The method of claim 9,
The ground voltage to which the display panel is grounded is a signal whose voltage level changes,
The touch driving signal corresponds to a ground voltage to which the display panel is grounded in frequency and phase.
11. The method of claim 10,
The ground voltage to which the display panel is grounded is
A touch display device in which a signal is modulated based on a ground voltage to which a micro control unit for detecting the presence or absence of a touch or a touch coordinate during the display driving period is grounded.
delete 12. The method of claim 11,
The first preamplifier,
a first inversion input terminal that outputs the touch driving signal to the first touch line and receives the first sensing signal from the first touch line; and
a first output stage for outputting the first input signal to the differential amplifier;
The second preamplifier,
a second inversion input terminal that outputs the touch driving signal to the second touch line and receives the second sensing signal from the second touch line; and
and a second output terminal for outputting the second input signal to the differential amplifier.
14. The method of claim 13,
a first feedback capacitor is electrically connected between the first inverting input terminal and the first output terminal of the first preamplifier;
A second feedback capacitor is electrically connected between the second inverting input terminal and the second output terminal of the second preamplifier.
14. The method of claim 13,
A first resistor is electrically connected between the first inverting input terminal and the first output terminal of the first preamplifier,
A second resistor is electrically connected between the second inverting input terminal and the second output terminal of the second preamplifier.
16. The method of claim 15,
In the differential amplifier, a resistor is electrically connected between an input terminal to which the first sensing signal or the second sensing signal is input and an output terminal to which the output signal is output.
14. The method of claim 13,
The first non-inverting input terminal and the second non-inverting input terminal are electrically connected to each other.
delete According to claim 1,
The touch circuit is
The touch display device further comprising an amplifier connected between the differential amplifier and the integrator.
A touch circuit for driving a display panel in which a plurality of data lines and a plurality of gate lines are disposed, a plurality of touch electrodes are disposed, and a plurality of touch lines electrically connected to and corresponding to the plurality of touch electrodes are disposed. in,
During a display driving period in which data voltages are applied to the plurality of data lines, a first sensing signal received from a first touch electrode through a first touch line among the plurality of touch lines and a second one of the plurality of touch lines a differential amplifier for outputting an output signal corresponding to a difference between a second sensing signal received from a second touch electrode through two touch lines;
an integrator for integrating and outputting the output signal or a signal processed by the output signal;
a first preamplifier receiving the first sensing signal through a first touch line among the plurality of touch lines and outputting a first input signal to the differential amplifier; and
a second preamplifier receiving the second sensing signal through a second touch line among the plurality of touch lines and outputting a second input signal to the differential amplifier;
The first preamplifier includes a first non-inverting input terminal to which a touch driving signal that is an AC signal, a modulated signal, or a pulse signal is input, and the second preamplifier is the AC signal, the modulated signal, or the pulse signal. a second non-inverting input terminal to which the touch driving signal is input;
A touch circuit in which a first amplifier is connected between the first pre-amplifier and the differential amplifier, and a second amplifier is connected between the second pre-amplifier and the differential amplifier.
delete 21. The method of claim 20,
The first preamplifier,
a first inversion input terminal that outputs the touch driving signal to the first touch line and receives the first sensing signal from the first touch line; and
a first output stage for outputting the first input signal to the differential amplifier;
The second preamplifier,
a second inversion input terminal that outputs the touch driving signal to the second touch line and receives the second sensing signal from the second touch line; and
and a second output terminal configured to output the second input signal to the differential amplifier.
23. The method of claim 22,
a first feedback capacitor is electrically connected between the first inverting input terminal and the first output terminal of the first preamplifier;
A second feedback capacitor is electrically connected between the second inverting input terminal and the second output terminal of the second preamplifier.
23. The method of claim 22,
A first resistor is electrically connected between the first inverting input terminal and the first output terminal of the first preamplifier,
A second resistor is electrically connected between the second inverting input terminal and the second output terminal of the second preamplifier.
25. The method of claim 24,
In the differential amplifier, a resistor is electrically connected between an input terminal to which the first sensing signal or the second sensing signal is input and an output terminal to which the output signal is output.
23. The method of claim 22,
The touch driving signal is a common voltage applied to the front surface of the display panel.
23. The method of claim 22,
The touch driving signal is a voltage corresponding to a ground voltage at which the display panel is grounded.
21. The method of claim 20,
The touch circuit further comprising an amplifier coupled between the differential amplifier and the integrator.
21. The method of claim 20,
and a multiplexer circuit for selecting the first and second touch lines for differential sensing from among the plurality of touch lines and electrically connecting them to the differential amplifier.
a display panel on which a plurality of data lines and a plurality of gate lines are disposed, a plurality of touch electrodes are disposed, and a plurality of touch lines electrically connected to the plurality of touch electrodes are disposed; and
During a display driving period in which data voltages are applied to the plurality of data lines, a difference between a first sensing signal and a second sensing signal received from a first touch line and a second touch line among the plurality of touch lines is applied. A touch circuit for obtaining touch presence or touch coordinates based on sensing data including values,
The touch circuit may include: a first preamplifier receiving the first sensing signal through a first touch line among the plurality of touch lines and outputting a first input signal to a differential amplifier; and
a second preamplifier receiving the second sensing signal through a second touch line among the plurality of touch lines and outputting a second input signal to the differential amplifier;
The first preamplifier includes a first non-inverting input terminal to which a touch driving signal that is an AC signal, a modulated signal, or a pulse signal is input, and the second preamplifier is the AC signal, the modulated signal, or the pulse signal. a second non-inverting input terminal to which the touch driving signal is input;
A first amplifier is connected between the first pre-amplifier and the differential amplifier, and a second amplifier is connected between the second pre-amplifier and the differential amplifier.
a display panel on which a plurality of data lines and a plurality of gate lines are disposed, a plurality of touch electrodes are disposed, and a plurality of touch lines electrically connected to the plurality of touch electrodes are disposed; and
In the touch sensing method of a touch display device comprising a touch circuit for detecting the presence or absence of a touch or touch coordinates based on sensing signals received from corresponding two or more touch electrodes through two or more touch lines among the plurality of touch lines,
During a display driving period in which data voltages are applied to the plurality of data lines, a first sensing signal is received from a first touch electrode through a first touch line among the plurality of touch lines, and a first sensing signal is received from among the plurality of touch lines. receiving a second sensing signal from a second touch electrode through a second touch line;
generating an output signal corresponding to a difference between the first sensing signal and the second sensing signal; and
and acquiring touch presence or touch coordinates based on the output signal,
The touch circuit may include: a first preamplifier receiving the first sensing signal through a first touch line among the plurality of touch lines and outputting a first input signal to a differential amplifier; and
a second preamplifier receiving the second sensing signal through a second touch line among the plurality of touch lines and outputting a second input signal to the differential amplifier;
The first preamplifier includes a first non-inverting input terminal to which a touch driving signal that is an AC signal, a modulated signal, or a pulse signal is input, and the second preamplifier is the AC signal, the modulated signal, or the pulse signal. a second non-inverting input terminal to which the touch driving signal is input;
A touch sensing method in which a first amplifier is connected between the first pre-amplifier and the differential amplifier, and a second amplifier is connected between the second pre-amplifier and the differential amplifier.

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