TWM491212U - Touch display device and driving circuit - Google Patents

Description

Touch display device and driving circuit

The present invention relates to the field of touch technologies, and in particular, to a touch display device and a driving circuit.

As an input medium, the touch screen is the most simple, convenient and natural human-machine dialogue mode.

Referring to FIG. 1 , a liquid crystal display device with an in-cell touch panel is shown in the prior art. The liquid crystal display device includes a thin film transistor (TFT) substrate from bottom to top. a liquid crystal layer 2 and a color filter (CF) substrate 3, wherein the TFT substrate comprises: a first glass substrate 11, a thin film transistor 12 on the first glass substrate 11, and a CF substrate The bottom to top includes a common electrode 31, a color filter 32, a touch screen 33, and a second glass substrate 34. The touch screen 33 in FIG. 1 can be a self-capacitive touch screen. Specifically, the self-capacitive touch screen detects a capacitance formed by a driving electrode or a sensing electrode and a ground end, and is based on a finger touch type. The position change is detected by the change in capacitance caused by the screen.

When the liquid crystal display device is actually displayed, the liquid crystal display driving circuit opens the thin film transistor 12 row by row through the gate line, and the data line supplies the pixel voltage to the pixel electrode 35 of each sub-pixel when the gate line opens the thin film transistor, the common electrode The pixel voltage is loaded on 31. Referring to Fig. 2, there is shown an equivalent circuit diagram of a sub-pixel unit in the liquid crystal display device shown in Fig. 1. The pixel electrode 35 and the common electrode 31 form an equivalent capacitance Clc. The electric field in the equivalent capacitance Clc passes through the liquid crystal molecules in the liquid crystal layer 2. The magnitude of the electric field determines the rotation angle of the liquid crystal molecules, and the rotation angle of the liquid crystal molecules Determine the strength of the sub-pixel ray in a particular direction.

With the increasing demand for touch screens, the prior art touch display technology also enables the common electrode to function as a detection electrode for self-capacitive touch detection. As shown in Figure 3, a schematic diagram of a common electrode is illustrated. The common electrode includes four rows and four columns of a plurality of square electrodes 36, each of which is connected to the drive wafer 37 by a connection line. The driving wafer 37 drives the plurality of square electrodes 36 in a time division manner. That is, the driving chip 37 drives the common electrode to the potential required for display during the display phase, and provides the touch detection signal to the common electrode during the touch detection phase.

However, in the touch detection phase, the common electrode also generates a plurality of parasitic capacitances, which affects the detection accuracy of the touch detection. Referring to FIG. 4, an equivalent circuit diagram of a sub-pixel unit of a touch display device including the common electrode shown in FIG. 3 is shown. The common electrode is used as a touch detection electrode, and the parasitic capacitance Cmg of the common electrode to the gate line, the parasitic capacitance Cms of the common electrode to the data line, and the parasitic capacitance Cs of the common electrode to the screen frame are easily generated. The presence of the above parasitic capacitance causes interference in touch detection.

The problem solved by the present invention is to provide a touch display device and a driving circuit to reduce the interference of the parasitic capacitance on the touch detection and improve the accuracy of the touch detection.

In order to solve the above problems, the present invention provides a touch display device for implementing touch sensing and display, comprising: a first substrate; a second substrate disposed opposite to the first substrate, the second substrate facing the first substrate a gate line, a data line, and a thin film transistor are disposed; the liquid crystal layer is located between the first substrate and the second substrate; the common electrode is located between the first substrate and the second substrate, and is used as a touch during the touch sensing stage The sensing circuit is configured to provide a first signal for implementing touch detection to the common electrode during the touch sensing phase; the driving circuit is further configured to provide the second signal to the gate line during the touch sensing phase, and the second signal can The thin film transistor is in a closed state, and at the same time, the charge and discharge capacity of the capacitor formed by the common electrode and the gate line is reduced; and/or the driving circuit is further configured to provide the third signal to the data line during the touch sensing phase, and third The signal can reduce the charge and discharge capacity of the capacitor formed by the common electrode and the data line.

Optionally, the second signal and the first signal are pulse signals of the same frequency in phase.

Optionally, the second signal and the first signal are pulse signals of the same frequency and the same frequency.

Optionally, the third signal and the first signal are pulse signals of the same frequency in phase.

Optionally, the third signal and the first signal are pulse signals of the same frequency and the same frequency. Optionally, the third signal is a signal that causes the data line to be in a floating state.

Optionally, the first signal, the second signal, or the third signal is a square wave signal, a sine wave signal, or a ladder signal.

Optionally, the driving circuit is further configured to provide a driving signal to the gate line during the display phase, a display signal to the data line, and a common voltage signal to the common electrode.

Optionally, the driving circuit comprises: a common electrode driving unit for generating a common voltage signal and a first pulse signal; and a gate driving unit connected to the plurality of gate lines for generating a driving signal, and also for generating a second pulse signal of the same frequency as the pulse signal; the data line driving unit is connected to the plurality of data lines for generating the display signal; the timing control unit is connected to the common electrode driving unit, the gate driving unit and the data line driving unit, The control gate driving unit sequentially supplies driving signals to the plurality of gate lines during the display phase, and controls the data line driving unit to provide a display signal to the data lines, and controls the common electrode driving unit to provide a common voltage signal to the common electrodes; the timing control unit further In the touch sensing phase, the control common electrode driving unit provides a first pulse signal to the common electrode to implement touch detection, and controls the gate driving unit to provide a second pulse in phase with the first pulse signal to the plurality of gate lines. Signal.

Optionally, the data line driving unit is further configured to generate a third pulse signal with the same frequency as the first pulse signal; the timing control unit is further configured to control the data line driving unit to provide the plurality of data lines in the touch sensing stage A third pulse signal with a pulse signal in phase.

Optionally, the driving circuit further includes: a switch disposed between the data line driving unit and the plurality of data lines, wherein the data line driving unit is configured to provide a pixel voltage as a display signal to the data line when the switch is turned on; the timing control unit and The switch is connected to control the switch to be turned on during the display phase, so that the data line driving unit supplies the pixel voltage to the data line; and is also used to control the switch to be turned off during the touch sensing phase, so that the data line is in a floating state.

Optionally, the driving circuit comprises: a common electrode driving unit for generating a common voltage signal and a first pulse signal; a gate driving unit connected to the plurality of gate lines for generating a driving signal; and a data line driving unit, and A plurality of data lines are connected for generating a display signal, and are also used for generating a third pulse signal having the same frequency as the first pulse signal or connected to the plurality of data lines through the switch; the timing control unit, and the common electrode driving unit and the gate The driving unit is connected to the data line driving unit, and is configured to control the gate driving unit to sequentially provide driving signals to the plurality of gate lines during the display phase, and control the data line driving unit to provide a display signal to the data lines, and control the common electrode driving unit to the common electrode. Providing a common voltage signal; the timing control unit is further configured to control the common electrode driving unit to provide a first pulse signal to the common electrode to implement touch detection during the touch sensing phase, and control the data line driving unit to provide the plurality of data lines The third pulse signal or the control switch of the same phase of the pulse signal is turned off to make the data line floating.

Optionally, the drive circuit is directly connected to the gate line.

Optionally, the driving circuit is connected to the gate line by capacitive coupling.

Correspondingly, the present invention further provides a driving circuit for driving a touch display device. The touch display device includes: a first substrate; a second substrate disposed opposite to the first substrate, the second substrate facing the surface of the first substrate a gate line, a data line, and a thin film transistor are disposed; the liquid crystal layer is located between the first substrate and the second substrate; the common electrode is located between the first substrate and the second substrate, and is used as a touch during the touch sensing stage The driving circuit includes: a first driving module configured to provide a first signal for implementing touch detection to the common electrode during the touch sensing phase; and a second driving module for the gate line during the touch sensing phase Providing a second signal, the second signal enables the thin film transistor to be in a closed state, and at the same time, reducing the charge and discharge capacity of the capacitor formed by the common electrode and the gate line; and/or the third driving module is used for the touch The sensing phase provides a third signal to the data line, and the third signal can reduce the charge and discharge capacity of the capacitor formed by the common electrode and the data line.

Optionally, the second signal and the first signal are pulse signals of the same frequency in phase.

Optionally, the second signal and the first signal are pulse signals of the same frequency and the same frequency.

Optionally, the third signal and the first signal are pulse signals of the same frequency in phase.

Optionally, the third signal and the first signal are pulse signals of the same frequency and the same frequency.

Optionally, the third signal is a signal that causes the data line to be in a floating state.

Optionally, the first signal, the second signal, or the third signal is a square wave signal, a sine wave signal, or a ladder signal.

Optionally, the first driving module is further configured to provide a common voltage signal to the common electrode during the display phase; the second driving module is further configured to provide a driving signal to the gate line during the display phase, and the third driving module is further configured to: Provide display signals to the data line during the display phase.

Optionally, the driving circuit comprises: a common electrode driving unit for generating a common voltage signal and a first pulse signal; and a gate driving unit connected to the plurality of gate lines for generating a driving signal, and also for generating a second pulse signal of the same frequency as the pulse signal; the data line driving unit is connected to the plurality of data lines for generating the display signal; the timing control unit is connected to the common electrode driving unit, the gate driving unit and the data line driving unit, The control gate driving unit sequentially supplies driving signals to the plurality of gate lines during the display phase, and controls the data line driving unit to provide a display signal to the data lines, and controls the common electrode driving unit to provide a common voltage signal to the common electrodes; the timing control unit further In the touch sensing phase, the control common electrode driving unit provides a first pulse signal to the common electrode to implement touch detection, and controls the gate driving unit to provide a second pulse in phase with the first pulse signal to the plurality of gate lines. Signal.

Optionally, the data line driving unit is further configured to generate a third pulse signal with the same frequency as the first pulse signal; the timing control unit is further configured to control the data line driving unit to provide the plurality of data lines in the touch sensing stage A third pulse signal with a pulse signal in phase.

Optionally, the driving circuit further includes: a switch disposed between the data line driving unit and the plurality of data lines, wherein the data line driving unit is configured to provide a pixel voltage as a display signal to the data line when the switch is turned on; the timing control unit and The switch is connected to control the switch to be turned on during the display phase, so that the data line driving unit supplies the pixel voltage to the data line; and is also used to control the switch to be turned off during the touch sensing phase, so that the data line is in a floating state.

Optionally, the driving circuit comprises: a common electrode driving unit for generating a common voltage signal and a first pulse signal; a gate driving unit connected to the plurality of gate lines for generating a driving signal; and a data line driving unit, and A plurality of data lines are connected for generating a display signal, and are also used for generating a third pulse signal having the same frequency as the first pulse signal or connected to the plurality of data lines through the switch; the timing control unit, and the common electrode driving unit and the gate The driving unit is connected to the data line driving unit, and is configured to control the gate driving unit to sequentially provide driving signals to the plurality of gate lines during the display phase, and control the data line driving unit to provide a display signal to the data lines, and control the common electrode driving unit to the common electrode. Providing a common voltage signal; the timing control unit is further configured to control the common electrode driving unit to provide a first pulse signal to the common electrode to implement touch detection during the touch sensing phase, and control the data line driving unit to provide the plurality of data lines The third pulse signal or the control switch of the same phase of the pulse signal is turned off to make the data line floating.

Optionally, the first driving module is directly connected to the gate line.

Optionally, the first driving module is connected to the gate line by capacitive coupling.

Compared with the prior art, the technical solution of the creation has the following advantages:

The driving circuit in the touch display device of the present invention can reduce the common electrode and the gate line by providing a first signal to the common electrode during the touch sensing phase, providing a second signal to the gate line, and/or providing a third signal. / or the charge and discharge power of the parasitic capacitor between the data lines, by reducing the charge and discharge power of the parasitic capacitor, the interference of the parasitic capacitor on the touch detection can be reduced, thereby improving the accuracy of the touch detection.

In order to make the above objects, features and advantages of the present invention more obvious and obvious, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

In order to solve the problems mentioned in the prior art, the present invention provides a touch display device. Referring to FIG. 5, a schematic diagram of an embodiment of the present touch display device is shown. The touch display device includes a first substrate (not shown), a second substrate 111, a liquid crystal layer (not shown), a common electrode 105, and a driving circuit 100. The first substrate serves as a glass substrate on the side of a color filter (CF).

The second substrate 111 serves as a glass substrate on the side of a Thin Film Transistor (TFT), and the second substrate 111 is disposed opposite to the first substrate.

The second substrate 111 is further provided with a plurality of gate lines G1, G2, ..., GM, a plurality of data lines S1, S2, ..., SN, and a thin film transistor 104, on the surface facing the first substrate. The drain of the thin film transistor 104 is connected to a pixel electrode (not shown), and the plurality of gate lines G1, G2, ..., GM are electrically connected to the gate of the thin film transistor 104 for carrying the gate of the thin film transistor 104. Into the driving signal, a plurality of data lines S1, S2, ..., SN are connected to the source of the thin film transistor 104 for supplying a pixel voltage to the source of the thin film transistor 104.

The liquid crystal layer is located between the first substrate and the second substrate 111.

The common electrode 105 is located between the first substrate and the second substrate 111. The common electrode 105 is used as a touch sensing electrode in the touch sensing phase and is used to load a common voltage (VCOM) during the display phase. Specifically, the common electrode 105 may include a plurality of electrode units arranged in a matrix, and the plurality of electrode units are detection electrodes that realize self-capacitance detection during touch sensing.

The driving circuit 100 is configured to provide a first signal for implementing touch detection to the common electrode 105 during the touch sensing phase; the driving circuit 100 is further configured to provide the second signal to the gate lines G1, G2, . . . The second signal enables the thin film transistor to be in a closed state, and at the same time, reduces the charge and discharge power of the capacitor formed by the common electrode and the gate line; and/or the driving circuit 100 is further configured to provide the third signal during the touch sensing stage. The third signal can reduce the charge and discharge capacity of the capacitor formed by the common electrode and the data line.

It should be noted that, here, reducing the charge and discharge capacity of the capacitor formed by the common electrode 105 and the gate line (data line) means that the charge and discharge are compared with the capacitor when the second signal (third signal) is not supplied. The power is reduced.

The first signal provided by the driving circuit to the common electrode and the second signal (third signal) provided by the touch display device can reduce the charge and discharge power of the parasitic capacitor between the common electrode and the gate line (data line). Therefore, the interference of the parasitic capacitor on the touch detection can be reduced, thereby improving the accuracy of the touch detection.

The principle that the touch display device of the embodiment shown in FIG. 5 can improve the touch detection accuracy will be described below with reference to the driving signal shown in FIG.

As shown in FIG. 5, in the embodiment, the driving circuit 100 includes a common electrode driving unit 103 connected to the common electrode 105 for generating a common voltage signal VCOM and a first pulse signal 201, and the first pulse signal 201 is The first signal. Here, the first pulse signal 201 is a square wave signal with a low level of 0V and a high level of 2V. The first pulse signal 201 is a detection signal that is loaded on a common electrode used as a touch sensing electrode to implement touch detection.

The gate driving unit 101 is connected to the plurality of gate lines G1, G2, . . . , and is used to generate the second pulse signal 202. The gate driving unit 101 can be directly connected to the gate lines G1, G2, ..., GM. It is also possible to connect to the gate lines G1, G2, . . . , by means of capacitive coupling.

The second pulse signal 202 is the second signal, where the second pulse signal 202 is a square wave signal with a low level of -12V and a high level of -10V. The second pulse signal 202 and the first pulse signal 201 are pulse signals of the same frequency and amplitude (both amplitudes are 2V). The high level of the second pulse signal 202 is much smaller than the turn-on voltage of the thin film transistor 104, so that the thin film transistor 104 is turned off, so that the signal loaded on the liquid crystal cell is not affected during the touch sensing phase, thereby enabling the touch. The display device can realize the normal display function.

The data line driving unit 102 is connected to the plurality of data lines S1, S2, ..., SN for generating the third pulse signal 203, and the third pulse signal 203 is the third signal, where the third pulse signal 203 is the low level. The square wave signal is 0V and the high level is 2V, and the third pulse signal 203 and the first pulse signal 201 are pulse signals of the same frequency and amplitude (both amplitudes are 2V).

A timing control unit (not shown) is connected to the common electrode driving unit 103, the gate driving unit 101, and the data line driving 102 unit for controlling the common electrode driving unit 103 to provide the first electrode to the common electrode 105 during the touch sensing phase. The pulse signal 201 is used to implement the touch detection, and the gate driving unit 101 is controlled to provide the second pulse signal 202 in phase with the first pulse signal 201 to the plurality of gate lines G1, G2, . . . , and the data line driving unit 102 is also controlled. The third pulse signal 203 is in phase with the first pulse signal 201 to the plurality of data lines S1, S2, ..., SN.

In the touch sensing stage, the driving circuit 100 of the touch display device of the present embodiment supplies the plurality of gate lines G1, G2, ..., GM with the same frequency and the same frequency as the first pulse signal 201 through the gate driving unit 101. The pulse signal 202 is such that even if the capacitor is formed between the common electrode 105 and the gate lines G1, G2, ..., GM, the two electrode common electrodes 105 and the gate lines G1, G2, ... GM of the capacitor are loaded with the same The frequency is the same as the signal of the same amplitude, that is, the same voltage value is loaded on both electrode plates of the capacitor at any time, so the capacitor is not charged and discharged, that is, the common electrode 105 and the gate lines G1, G2, ... GM The charge and discharge capacity of the constructed capacitor is zero. The charge and discharge amount is reduced to zero as compared with when the second pulse signal 202 is not loaded on the gate lines G1, G2, ... GM. That is to say, the capacitor between the common electrode 105 and the gate lines G1, G2, ... GM cannot interfere with the touch detection in the actual circuit, thereby improving the accuracy of the touch detection.

The driving circuit 100 of the touch display device of the present embodiment is further provided with the same frequency and the same frequency as the first pulse signal 201 by the data line driving unit 102 to the plurality of data lines S1, S2, ..., SN through the data line driving unit 102. The pulse signal 203 is such that even if the common electrode 105 and the data lines S1, S2, ... SN form a capacitor, the two plate common electrodes 105 of the capacitor and the data lines S1, S2, ... SN are loaded with the same frequency. The same amplitude signal, the same voltage value is loaded on both electrode plates of the capacitor at any time, so the capacitor does not charge and discharge, that is, the charge and discharge capacity of the capacitor formed by the common electrode 105 and the data lines S1, S2, ... SN Zero. The charge and discharge amount is reduced to zero as compared with when the third pulse signal 203 is not loaded on the data lines S1, S2, ..., SN. That is to say, the capacitor between the common electrode 105 and the data lines S1, S2, ... SN cannot interfere with the touch detection in the actual circuit, thereby improving the accuracy of the touch detection.

It should be noted that, in the embodiment, the second pulse signal 202 and the third pulse signal 203 are the same frequency signal as the first pulse signal 201, and the common electrode and the gate line (data line) are formed. The capacitor is no longer charged or discharged. However, the present invention does not limit this. The second pulse signal 202 and the third pulse signal 203 are all signals in phase with the first pulse signal 201, even if the voltage values of the two electrodes on the capacitor are loaded at any time. Differently, since the signals of the two electrode plates are in phase with the same frequency, the potential difference between the capacitor electrode plates is reduced compared to the gate line without adding a signal, that is, the common electrode 105 and the gate line G1 can be achieved. The purpose of reducing the charge and discharge capacity of the capacitor formed by G2, GM (data lines S1, S2, ... SN).

It should be noted that, in this embodiment, the first signal, the second signal, and the third signal are all pulse signals, and the present invention does not limit whether the pulse signal is a pulse signal, as long as it is correspondingly loaded on the common electrode 105 and the gate line G1. , G2 ... GM and data lines S1, S2 ... SN can reduce the power of the capacitor signal can be.

It should be noted that, in this embodiment, the first signal, the second signal, and the third signal are square wave pulse signals, and the present invention does not limit this. In other embodiments, the first signal, the first The second signal and the third signal can also be sinusoidal signals or ladder signals.

The driving circuit 100 in the touch display device of the embodiment can reduce the influence of the parasitic capacitance between the common electrode 105 and the gate lines G1, G2, ..., GM, and can also reduce the common electrode 105 and the data lines S1, S2... The effect of parasitic capacitance between SNs. However, in the touch display device of other embodiments, only the gate driving unit 101 may be disposed, causing the parasitic capacitance of the common electrode 105 and the gate lines G1, G2, ..., GM to be reduced. The effect of the detected interference. Correspondingly, for the embodiment in which only the gate driving unit 101 is provided, the timing control unit only needs to control the gate driving unit 101 to provide the second pulse lines in phase with the first pulse signal 201 to the plurality of gate lines G1, G2, ..., GM. Signal 202.

Alternatively, in other embodiments of the touch display device, only the data line driving unit 102 may be disposed, causing the effect of reducing the interference of the parasitic capacitance of the common electrode 105 and the data lines S1, S2, ... SN on the touch detection. Correspondingly, for the embodiment in which only the data driving unit 102 is provided, the timing control unit only needs to control the data driving unit 102 to provide the third pulse signal 203 in phase with the first pulse signal 201 to the plurality of data lines S1, S2, ..., SN.

Referring to FIG. 5 and FIG. 6 , the driving circuit 100 of the touch display device of the embodiment has a process of driving display and driving touch detection. The drive circuit 100 integrates the circuit portion that drives the display and the circuit portion that drives the touch detection.

Specifically, the driving circuit 100 is further configured to provide driving signals to the gate lines G1, G2, . . . , GM during the display phase, display signals to the data lines S1, S2, . . . , SN, and provide common voltage signals to the common electrode 105. However, the present invention does not limit this. In other embodiments, the driving circuit may only have the function of driving the circuit portion of the touch detection, as long as the parasitic capacitance interference can be reduced in the touch sensing phase.

Specifically, the driving circuit 100 has a total timing controller (not shown) for driving the display phase and the touch sensing phase in a time division manner. For the touch sensing phase driving circuit 100, please refer to the above description, and details are not described herein again. The mode of operation of the stage drive circuit 100 will be described in detail below.

As shown in FIG. 6, the gate driving unit 101 of the driving circuit 100 is further configured to generate a driving signal. Specifically, the driving circuit here is a timing pulse signal for sequentially driving the gate lines G1, G2, G3, ... GM, and the pulse signal is a pulse signal with a high level of 15V and a low level of 0.

The data line driving unit 102 is further configured to generate a display signal D;

The common electrode driving unit 103 is also used for the common voltage signal VCOM.

The timing control unit is connected to the common electrode driving unit 103, the gate driving unit 101 and the data line driving unit 102, and is configured to control the gate driving unit 101 to the plurality of gate lines G1, G2, G3, ..., GM in sequence during the display phase. The driving signal is provided, and the control data line driving unit 102 provides the display signal D to the data lines S1, S2, . . . , SN, and controls the common electrode driving unit 103 to provide the common voltage signal VCOM to the common electrode 105. The timing control unit is also used for the touch sensing. In the stage, the control common electrode driving unit 103 supplies the first pulse signal 201 to the common electrode 105 to implement touch detection, and controls the gate driving unit 101 to provide the first pulse to the plurality of gate lines G1, G2, G3, . . . The second pulse signal 202 of the signal 201 is in phase, and the timing control unit is further configured to, in the touch sensing phase, control the data line driving unit 102 to provide the third data line S1, S2, ..., SN with the third phase in phase with the first pulse signal 201. Pulse signal 202.

The drive circuit 100 will be further described below in conjunction with a specific circuit.

Referring to Figure 7, a schematic diagram of an embodiment of the drive circuit of Figure 5 is shown. In the embodiment, the driving circuit 100 further includes an on-screen gate circuit 106 disposed on the screen (the area indicated by the dotted line in FIG. 5 is a screen). It should be noted that here, a touch display device having a resolution of 1280×720 RGB is taken as an example. 640 gate lines are generated on the left and right sides of the screen body. Specifically, the on-screen gate circuit 106 is connected by 640 RS cell sub-circuits (RS Cell is used as a latch), and the VGL end of the RS Cell sub-circuit is carried. The voltage source for turning off the thin film transistor TFT on the gate line, the CK terminal is the clock input signal, the SP terminal is the data registration end, and the OUT is the output terminal.

The logic control signals that the gate driving unit 101 needs to provide to the RS cell sub-circuit include: CK1_L, CK2_L, SP_L, CK1_R, CK2_R, SP_R, and VGLO to implement the gate lines G1, G2, G3, ... GM (M is 1280). Drive.

Referring to Figure 8, a schematic diagram of an embodiment of the gate drive unit 101 of Figure 5 is illustrated. The gate driving unit 101 includes:

The charge pump 1012 includes a first output terminal for outputting a first voltage VGH (15V) for driving the thin film transistor to be turned on, and a second output terminal for outputting a second voltage VGL1 (-12V) for controlling the thin film transistor to be turned off. .

The voltage regulator 1013 is connected to the second output end of the charge pump 1012 for adjusting the second voltage outputted by the charge pump 1012 to form a third voltage VGL2 (-10V), and the second voltage and the third voltage respectively correspond to the second The low level and the high level of the pulse signal 202.

a plurality of high voltage driving units 1015, the input end is connected to the first output end and the second output end of the charge pump 1012 and the voltage regulator 1013, and the output end is connected to the SP end of the data registration end of the RS Cell sub-circuit, and the CK end is connected. The logic control signals CK1_L, CK2_L, SP_L, CK1_R, CK2_R, and SP_R are output.

Specifically, the high voltage driving unit 1015 includes: a first PMOS transistor P1, a source connected to the first output end of the charge pump 1012 (loaded with the first voltage VGH), and a gate and a first timing controller (not shown) Connected; the first NMOS transistor N1A, the source is connected to the second output terminal of the charge pump 1012 (loaded with the second voltage VGL1), and the gate is connected to the third timing controller and the second timing controller; The NMOS transistor N1B has a source connected to the voltage regulator 1013 (loaded with the third voltage VGL2), the gate is connected to the second timing controller, and the drain is connected to the drain of the first NMOS transistor N1A and the first PMOS transistor P1. Extremely connected.

The power signal unit 1014 has an input end connected to the second output end of the charge pump 1012 and a voltage regulator, and the output end is connected to the voltage source VGL input end of the plurality of RS cell sub-circuits.

Specifically, the power signal unit 1014 includes: a third NMOS transistor N2A and a fourth NMOS transistor N2B; a third output terminal of the source charge pump 1012 of the third NMOS transistor N2A, and the gate is connected to the second timing controller; The source of the NMOS transistor N2B is connected to the output of the voltage regulator 1013, the gate is connected to the second timing controller, and the drain is connected to the drain of the third NMOS transistor.

The timing control unit 1011 includes a first timing controller (not shown) connected to the high voltage driving unit 1015 for driving the high voltage driving unit 1015 to alternately output the first voltage VGH and the second voltage VGL1 to respectively provide multiple gates. The pole line is time-divisionally loaded with the first voltage VGH and the second voltage VGL1 to provide the driving signals required for the display phase to the plurality of gate lines in a time division manner.

The timing control unit 1011 further includes a second timing controller connected to the high voltage driving unit 1015 and the power signal unit 1014 for driving the power signal unit 1014 to alternately output the second voltage VGL1 and the third voltage VGL2 to the voltage source of the RS cell sub-circuit. a VGL input terminal; the second timing controller is further configured to control the high voltage driving unit 1015 to alternately output the second voltage VGL1 and the third voltage VGL2 to the data registration end SP of the RS Cell sub-circuit, so as to input the voltage source VGL of the RS Cell sub-circuit The signal of the terminal can be output to the output terminal OUT of the RS cell sub-circuit to provide the second pulse signal 202 required for the touch sensing phase to the plurality of gate lines.

The timing control unit 1011 further includes: a total timing controller (not shown) connected to the first timing controller and the second timing controller, configured to control the first timing controller to be driven during the display phase, for The touch sensing phase controls the second timing controller to drive.

Referring to Figure 9, a schematic diagram of an embodiment of the data line drive unit of Figure 5 is shown. Specifically, the data line driving unit includes: a timing control unit 1011 and a plurality of data line signal registers 1023, and the plurality of data line signal registers 1023 correspond to the plurality of data lines S1, S2, ..., SN.

The data line signal register 1023 includes a positive polarity driving circuit 1021, and the output end is connected to the corresponding data line for generating a first pixel voltage for deflecting the liquid crystal molecules in the first direction as a display signal, and the positive polarity driving circuit is adjacent to the output end. A first switch T1A is provided in the middle.

The negative polarity driving circuit 1022 has an output end connected to the corresponding data line for generating a second pixel voltage for deflecting the liquid crystal molecules in the second direction as a display signal, and a negative polarity driving circuit is provided with the second switch T1D near the output end.

The data line driving unit further includes: a third switch T1B, one end is connected to the voltage source VSP (the voltage of the VSP is 2V), the other end is connected to the output end of the data line driving unit; the fourth switch T1C is connected to the ground end, and the other is connected One end is connected to the output of the data line drive unit.

The timing control unit 1011 further includes: a third timing controller (not shown) driven by the total timing controller in the display phase, and connected to the positive polarity driving circuit 1021 and the negative polarity driving circuit 1022 for alternately driving the first switch The T1A is turned on, and the second switch T1D is turned on, so that the positive polarity driving circuit and the negative polarity driving circuit respectively output the first pixel voltage and the second pixel voltage.

The timing control unit 1011 further includes: a fourth timing controller driven by the total timing controller in the touch sensing phase for alternately driving the third switch T1B to be turned on (not shown) and the fourth switch T1C being turned on for time-sharing output. The high level is the third pulse signal 203 of the voltage source voltage and the low level is 0.

Referring to FIG. 10, FIG. 9 is a schematic diagram of an embodiment of the common electrode driving unit of FIG. 1. The common electrode driving unit includes:

The touch detection circuit 1033 is connected to the plurality of electrodes of the common electrode 105 through the first switches K1A, K2A, ..., KNA, respectively, for loading the first electrodes into the first switches when the first switches K1A, K2A, ..., KNA are turned on. Pulse signal for touch detection.

The common electrode driving buffer 1032 is connected to the plurality of electrodes of the common electrode 105 through the second switches K1B, K2B, ..., KNB, respectively, for loading the plurality of electrodes when the second switches K1B, K2B, ..., KNB are turned on. Voltage signal.

The timing control unit 1011 is connected to the first switches K1A, K2A, ..., KNA and the second switches K1B, K2B, ..., KNB for driving the first switches K1A, K2A, ..., KNA to be turned on during the touch sensing phase, thereby enabling touch detection. The circuit 1033 performs self-capacitance detection on the plurality of electrodes of the common electrode 105; and is also used to drive the second switches K1B, K2B, ..., KNB to be turned on during the display phase, so that the common electrode driving buffer 1032 supplies the plurality of electrodes of the common electrode 105 Public voltage signal.

It should be noted that, FIG. 8 , FIG. 9 and FIG. 10 are respectively a specific implementation circuit of the gate driving unit 101 , the data line driving unit 102 and the common electrode driving unit 103 , which is not limited in this embodiment. In other embodiments, The gate driving unit 101, the data line driving unit 102, and the common electrode driving unit 103 may also employ other circuits.

In addition, in other embodiments, the gate driving unit (or the data line driving unit) of the driving circuit can also realize only the display function, and the data line driving circuit of the touch sensing stage is directed to the data line (or the gate line driving circuit to the gate) The line) provides a pulse signal corresponding to the first signal, that is, only reduces the interference of the data line (or the gate line) and the parasitic capacitance of the common electrode on the touch detection, and can also achieve the purpose of improving the touch detection accuracy.

It should be noted that, in the above embodiment, the third signal is a signal provided by the driving circuit to the data line, and the charging of the capacitor is reduced by the third signal loaded on the data line and the first signal loaded on the common electrode. Discharged electricity. However, the present invention does not limit this. In other embodiments, the third signal may also be a signal that is not loaded on the data line.

Referring to FIG. 11, a schematic diagram of another embodiment of the present touch display device is shown. The difference between the embodiment and the embodiment shown in FIG. 5 is not described again. The difference from the embodiment shown in FIG. 5 is that the driving circuit and the data line are coupled by a switch (not shown). The third signal 303 is a signal for controlling the switch to be turned off, so that the data line is in a floating state during the touch sensing phase. The floating state here means that the data line connected to the driving circuit in the original display phase is turned off during the touch sensing phase.

In this way, the data line is no longer loaded with any signal during the touch sensing phase and the driving circuit is closed. Therefore, in the touch sensing stage, the electrode plate corresponding to the data line and the data line are not connected to any device, and the capacitor is connected. The charging and discharging are not performed, thereby reducing the charge and discharge power and improving the accuracy of the touch detection.

Specifically, for a driving circuit that has both a display function and a touch detection function, the driving circuit is the same as that of the previous embodiment, and the driving circuit is different from the previous embodiment in that the driving circuit further includes: The switch is disposed between the data line driving unit and the plurality of data lines, and the data line driving unit is configured to supply the pixel voltage to the data line as the display signal when the switch is turned on. The timing control unit is connected to the switch, and is configured to control the switch to be turned on during the display phase, so that the data line driving unit supplies the pixel voltage to the data line; and is further configured to control the switch to be turned off by the third signal 303 during the touch sensing phase to make the data line It is in a floating state. To reduce the interference of the data line and the parasitic capacitance of the common electrode on the touch detection during the touch sensing phase.

It should be noted that, in the embodiment shown in FIG. 11, the gate driving unit further supplies the plurality of gate lines G1, G2, G3, . . . GM with the second pulse of the same frequency as the first pulse signal 301. Signal 302 to simultaneously reduce the interference of the common electrode with the gate line and the parasitic capacitance of the data line. In other embodiments, the gate driving unit of the driving circuit can also implement only the display function, and the touch sensing phase driving circuit causes the data line to be in a floating state, that is, only reduces the parasitic capacitance of the data line and the common electrode to the touch detection. The interference can also achieve the purpose of improving the accuracy of touch detection.

Correspondingly, the present invention also provides a driving circuit. In the touch display device, the touch display device includes: a first substrate; a second substrate disposed opposite to the first substrate, and the second substrate is disposed on a surface of the first substrate a gate line, a data line, and a thin film transistor; the liquid crystal layer is located between the first substrate and the second substrate; the common electrode is located between the first substrate and the second substrate, and is used as a touch sensing in the touch sensing stage electrode.

The driving circuit includes: a first driving module, configured to provide a first signal for implementing touch detection to the common electrode during the touch sensing phase; and a second driving module for providing the second gate to the gate line during the touch sensing phase The signal, the second signal enables the thin film transistor to be turned off, and at the same time reduces the charge and discharge capacity of the capacitor formed by the common electrode and the gate line; and/or the third driving module is used in the touch sensing stage The data line provides a third signal, and the third signal can reduce the charge and discharge capacity of the capacitor formed by the common electrode and the data line.

Specifically, the first driving module includes a common electrode driving unit and a portion of the timing control unit that drives the common electrode driving unit; the second driving module includes: a gate driving unit and a timing control unit that drives the gate driving unit. The third driving module includes a data line driving unit and a portion of the timing control unit that drives the data line driving unit.

Related descriptions of the driving circuit have been described in the related embodiments of the touch display device, and are not described herein again.

Although the present disclosure is as described above, the present creation is not limited thereto. Any changes and modifications can be made by those skilled in the art without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be limited to the scope defined by the claims.

1‧‧‧Substrate
11‧‧‧First glass substrate
12‧‧‧film transistor
100‧‧‧ drive circuit
101‧‧‧ gate drive unit
102‧‧‧Data line drive unit
103‧‧‧Common electrode drive unit
104‧‧‧film transistor
105‧‧‧Common electrode
106‧‧‧On-screen gate circuit
1011‧‧‧Sequence Control Unit
1012‧‧‧Charge pump
1013‧‧‧Voltage regulator
1014‧‧‧Power signal unit
1015‧‧‧High voltage drive unit
1021‧‧‧Positive drive circuit
1022‧‧‧Negative drive circuit
1023‧‧‧Data line signal register
1032‧‧‧Common electrode drive buffer
1033‧‧‧Touch detection circuit
111‧‧‧second substrate
2‧‧‧Liquid layer
201‧‧‧First pulse signal
202‧‧‧second pulse signal
203‧‧‧ third pulse signal
3‧‧‧Color filter substrate
31‧‧‧Common electrode
32‧‧‧Color filters
33‧‧‧Touch screen
34‧‧‧Second glass substrate
35‧‧‧pixel electrode
36‧‧‧square electrode
37‧‧‧Drive chip
301‧‧‧First pulse signal
302‧‧‧second pulse signal
303‧‧‧ Third signal
Clc‧‧‧ equivalent capacitance
Cms‧‧‧ parasitic capacitance
Cmg‧‧‧ parasitic capacitance
CK‧‧‧ data login
CK1_L‧‧‧ logical control signal
CK2_L‧‧‧ logical control signal
CK1_R‧‧‧ logical control signal
CK2_R‧‧‧ logical control signal
D‧‧‧ display signal
N1A‧‧‧First NMOS tube
N2A‧‧‧ third NMOS tube
N1B‧‧‧ second NMOS tube
N2B‧‧‧ fourth NMOS tube
G1, G2~GM‧‧‧ gate line
P1‧‧‧First PMOS tube
S1, S2~SN‧‧‧ data line
SP‧‧‧ data login
SP_L‧‧‧Logical Control Signal
SP_R‧‧‧Logical Control Signal
RS Cell‧‧‧Subcircuit
K1A, K2A~KNA‧‧‧ first switch
K1B, K2B~KNB‧‧‧ second switch
VCOM‧‧‧ public voltage signal
VGL‧‧‧ voltage source
VSP‧‧‧ voltage source
VGH‧‧‧ first voltage
VGL1‧‧‧second voltage
VGL2‧‧‧ third voltage
T1A‧‧‧ first switch
T1D‧‧‧ second switch
T1B‧‧‧ third switch
T1C‧‧‧fourth switch
OUT‧‧‧ output

FIG. 1 is a schematic diagram of an in-cell touch screen liquid crystal display device of the prior art. Figure 2 is an equivalent circuit diagram of a sub-pixel unit in Figure 1. FIG. 3 is a schematic diagram of a common electrode having a self-capacitive touch detection function in the prior art. Fig. 4 is an equivalent circuit diagram of a sub-pixel unit in which a common electrode is used as a touch electrode in the prior art. FIG. 5 is a schematic diagram of an embodiment of the present touch display device. Figure 6 is a schematic diagram of the driving signal of the touch display device shown in Figure 5. Figure 7 is a schematic diagram of an embodiment of the drive circuit of Figure 5. Figure 8 is a schematic view of an embodiment of the gate drive unit of Figure 5. Figure 9 is a schematic view of an embodiment of the common electrode driving unit of Figure 5. Figure 10 is a schematic view of an embodiment of the data line driving unit of Figure 5. 11 is a schematic view of another embodiment of the present touch display device.

201‧‧‧First pulse signal

202‧‧‧second pulse signal

203‧‧‧ third pulse signal

D‧‧‧ display signal

G1, G2~GM‧‧‧ gate line

VCOM‧‧‧ public voltage signal

VSP‧‧‧ voltage source

VGH‧‧‧ first voltage

VGL1‧‧‧second voltage

VGL2‧‧‧ third voltage

Claims (28)

A touch display device is configured to implement touch sensing and display. The touch display device includes: a first substrate; a second substrate disposed opposite to the first substrate, the second substrate facing the first substrate a gate line, a data line and a thin film transistor are disposed on the surface; a liquid crystal layer is located between the first substrate and the second substrate; a common electrode is located between the first substrate and the second substrate The touch sensing phase is used as a touch sensing electrode; and a driving circuit is configured to provide a first signal for implementing touch detection to the common electrode during the touch sensing phase; the driving circuit is also used for touch sensing Providing a second signal to the gate line, the second signal enabling the thin film transistor to be in a closed state, and reducing the charge and discharge capacity of the capacitor formed by the common electrode and the gate line; and/or The driving circuit is further configured to provide a third signal during the touch sensing phase, wherein the third signal can reduce the charge and discharge power of the capacitor formed by the common electrode and the data line. The touch display device of claim 1, wherein the second signal and the first signal are pulse signals of the same frequency in phase. The touch display device of claim 1, wherein the second signal and the first signal are the same amplitude pulse signal. The touch display device of claim 1, wherein the driving circuit provides the third signal to the data line, wherein the third signal and the first signal are pulse signals of the same frequency in phase. The touch display device of claim 1, wherein the driving circuit provides the third signal to the data line, the third signal and the first signal being the same frequency pulse signal of the same frequency. The touch display device of claim 1, wherein the driving circuit and the data line are coupled by a switch, and the third signal is a signal for turning off the switch, so that the data line is in a floating state. The touch display device of claim 1, wherein the first signal, the second signal or the third signal is a square wave signal, a sine wave signal or a step signal. The touch display device of claim 1, wherein the driving circuit is further configured to provide a driving signal to the gate line during the display phase, a display signal to the data line, and the common voltage signal to the common electrode. The touch display device of claim 8, wherein the driving circuit comprises: a common electrode driving unit for generating the common voltage signal and a first pulse signal; a gate driving unit, and a plurality of gate lines Connected for generating the driving signal, and for generating a second pulse signal having the same frequency as the first pulse signal; a data line driving unit connected to the plurality of data lines for generating the display signal; The sequence control unit is connected to the common electrode driving unit, the gate driving unit and the data line driving unit, and is configured to control the gate driving unit to sequentially provide the driving signal to the plurality of gate lines during the display phase, the control The data line driving unit provides a display signal to the data line, and controls the common electrode driving unit to provide the common voltage signal to the common electrode; the timing control unit is further configured to control the common electrode driving unit to the public during the touch sensing phase The electrode provides the first pulse signal to implement touch detection, and controls the gate driving unit to provide the first pulse to the plurality of gate lines The second phase of the pulse signal with the number. The touch display device of claim 9, wherein the data line driving unit is further configured to generate a third pulse signal having the same frequency as the first pulse signal; the timing control unit is further configured to be in a touch sensing stage. Controlling the data line driving unit to provide the third pulse signal in phase with the first pulse signal to the plurality of data lines. The touch display device of claim 9, wherein the driving circuit further comprises: a switch disposed between the data line driving unit and the plurality of data lines, wherein the data line driving unit is configured to be used when the switch is turned on Providing a pixel voltage as a display signal to the data line; the timing control unit is connected to the switch for controlling the switch to be turned on during the display phase, so that the data line driving unit supplies the pixel voltage to the data line; The touch sensing phase controls the switch to be turned off by the third signal to keep the data line in a floating state. The touch display device of claim 8, wherein the driving circuit comprises: a common electrode driving unit for generating the common voltage signal and the first pulse signal; a gate driving unit, and a plurality of gate lines Connected to generate the driving signal; a data line driving unit connected to the plurality of data lines for generating the display signal, and for generating a third pulse signal having the same frequency as the first pulse signal; or The data line driving unit and the plurality of data lines are coupled by a switch, the data line driving unit is configured to provide the third signal for controlling the switch to be turned off; and a timing control unit, and the common electrode driving unit and the gate The pole driving unit is connected to the data line driving unit, and is configured to control the gate driving unit to sequentially provide driving signals to the plurality of gate lines during the display phase, and control the data line driving unit to provide the display signal to the plurality of data lines. Controlling the common electrode driving unit to supply the common voltage signal to the common electrode; the timing control unit is further configured to control the common electrode during the touch sensing phase The moving unit provides the first pulse signal to the common electrode to implement touch detection, and controls the data line driving unit to provide a third pulse signal in phase with the first pulse signal to the plurality of data lines or through the third The signal controls the switch to be turned off to leave the plurality of data lines in a floating state. The touch display device of claim 1, wherein the driving circuit is directly connected to the gate line. The touch display device of claim 1, wherein the driving circuit is connected to the gate line by capacitive coupling. a driving circuit for driving a touch display device, the touch display device comprising: a first substrate; a second substrate disposed opposite to the first substrate, the second substrate being disposed on a surface of the first substrate a gate line, a data line and a thin film transistor; a liquid crystal layer between the first substrate and the second substrate; a common electrode between the first substrate and the second substrate, in contact The control sensing phase is used as a touch sensing electrode; the driving circuit includes: a first driving module, configured to provide a first signal for implementing touch detection to the common electrode during a touch sensing phase; and a second driving mode The group is configured to provide a second signal to the gate line during the touch sensing phase, the second signal enables the thin film transistor to be in a closed state, and at the same time, reduce the capacitor formed by the common electrode and the gate line And a third driving module is configured to provide a third signal during the touch sensing phase, wherein the third signal can reduce the charge and discharge capacity of the capacitor formed by the common electrode and the data line. The driving circuit of claim 15, wherein the second signal and the first signal are pulse signals of the same frequency in phase. The driving circuit of claim 15, wherein the second signal and the first signal are the same amplitude pulse signal. The driving circuit of claim 15, wherein the third driving module provides the third signal to the data line, and the third signal and the first signal are pulse signals of the same frequency in phase. The driving circuit of claim 15, wherein the third driving module provides the third signal to the data line, and the third signal and the first signal are the same frequency pulse signal of the same frequency. The driving circuit of claim 15, wherein the third driving module and the data line are coupled by a switch, and the third signal is a signal for turning off the switch, so that the data line is in a floating state. The driving circuit of claim 15, wherein the first signal, the second signal or the third signal is a square wave signal, a sine wave signal or a step signal. The driving circuit of claim 15, wherein the first driving module is further configured to provide a common voltage signal to the common electrode during the display phase; the second driving module is further configured to provide the gate line during the display phase. A driving signal, the third driving module is further configured to provide a display signal to the data line during the display phase. The driving circuit of claim 22, wherein the driving circuit comprises: a common electrode driving unit for generating the common voltage signal and the first pulse signal; and a gate driving unit connected to the plurality of gate lines, For generating the driving signal, and for generating a second pulse signal having the same frequency as the first pulse signal; a data line driving unit connected to the plurality of data lines for generating the display signal; and a timing control The unit is connected to the common electrode driving unit, the gate driving unit and the plurality of data line driving units, and is configured to control the gate driving unit to sequentially provide the driving signal to the plurality of gate lines during the display phase, and control the The data line driving unit provides the display signal to the data line, and controls the common electrode driving unit to provide the common voltage signal to the common electrode; the timing control unit is further configured to control the common electrode driving unit to the touch sensing stage The common electrode provides the first pulse signal to implement touch detection, and controls the gate driving unit to provide the first pulse to the plurality of gate lines The second phase of the pulse signal with the number. The driving circuit of claim 23, wherein the data line driving unit is further configured to generate a third pulse signal at the same frequency as the first pulse signal; the timing control unit is further configured to control the touch sensing stage The data line driving unit provides the third pulse signal in phase with the first pulse signal to the plurality of data lines. The driving circuit of claim 23, wherein the driving circuit further comprises: a switch disposed between the data line driving unit and the plurality of data lines, wherein the data line driving unit is configured to move the plurality of data lines when the switch is turned on The data line provides a pixel voltage as the display signal; the timing control unit is connected to the switch for controlling the switch to be turned on during the display phase, so that the data line driving unit supplies the pixel voltage to the data line; and is also used for the touch The sensing phase controls the switch to be turned off by the third signal to keep the data line in a floating state. The driving circuit of claim 22, wherein the driving circuit comprises: a common electrode driving unit for generating the common voltage signal and the first pulse signal; and a gate driving unit connected to the plurality of gate lines, For generating the driving signal; a data line driving unit, connected to the plurality of data lines, for generating the display signal, and for generating a third pulse signal having the same frequency as the first pulse signal; or the data line The driving unit and the plurality of data lines are coupled by a switch, the data line driving unit is configured to provide the third signal for controlling the switch to be turned off; and a timing control unit, and the common electrode driving unit and the gate driving unit And the data line driving unit is configured to control the gate driving unit to sequentially provide the driving signal to the plurality of gate lines during the display phase, and control the data line driving unit to provide the display signal to the data line to control the common electrode driving. The unit provides the common voltage signal to the common electrode; the timing control unit is further configured to control the common electrode driving unit to the touch sensing stage The common electrode provides the first pulse signal to implement touch detection, and controls the data line driving unit to provide the third pulse signal in phase with the first pulse signal to the plurality of data lines or control the switch through the third signal Close to leave the data line in a floating state. The driving circuit of claim 15, wherein the first driving module is directly connected to the gate line. The driving circuit of claim 15, wherein the first driving module is connected to the gate line by capacitive coupling.