阅读说明：本技术 触控显示控制电路、控制方法以及电子设备 (Touch display control circuit, control method and electronic equipment ) 是由 王运华 于 2018-07-19 设计创作，主要内容包括：本发明提供了一种触控显示控制电路、控制方法以及电子设备,该控制电路用于驱动STN-LCD、TN-LCD、CSTN-LCD液晶屏,包括显示驱动电路以及触控检测电路。其中,显示驱动电路包括信号传输走线、多组信号选择电路以及参考电压产生电路,信号传输走线用于传输栅极信号以及公共信号,信号选择电路基于显示控制时序或显示触控控制时序选通预设控制电压,参考电压产生电路提供预设控制电压。触控检测电路与信号选择电路相连,基于显示触控控制时序,进行触控检测。可见,本方案提供的触控显示控制电路,能在不变更原液晶屏幕结构的基础下,使STN-LCD、TN-LCD、CSTN-LCD等液晶屏具有触控功能。(The invention provides touch display control circuits, control methods and electronic equipment, wherein the control circuits are used for driving STN-LCD, TN-LCD and CSTN-LCD liquid crystal screens and comprise display drive circuits and touch detection circuits, the display drive circuits comprise signal transmission wires, a plurality of groups of signal selection circuits and reference voltage generation circuits, the signal transmission wires are used for transmitting grid signals and common signals, the signal selection circuits gate preset control voltages based on display control time sequences or display touch control time sequences, and the reference voltage generation circuits provide the preset control voltages.)

1, kinds of touch-control display control circuit, its characterized in that is applied to the drive LCD screen, touch-control display control circuit includes:

the display driving circuit comprises a signal transmission line, a signal selection circuit and a reference voltage generation circuit, wherein the signal transmission line is used for transmitting a grid signal and a public signal, the signal selection circuit gates a preset control voltage based on a display control time sequence or a display touch control time sequence, and the reference voltage generation circuit is connected with the signal selection circuit and used for providing the preset control voltage;

and the touch detection circuit is connected with the signal selection circuit and is used for performing touch detection based on the display touch control time sequence.

2. The touch display control circuit of claim 1, wherein the signal selection circuit comprises:

the grid signal selection sub-circuit is connected with the reference voltage generation circuit, gates a target grid voltage based on the display control time sequence and transmits the target grid voltage to the grid wires in the signal transmission wires;

and the common electrode signal selection sub-circuit is connected with the reference voltage generation circuit, gates a target common voltage based on the display control time sequence or the display touch control time sequence, and transmits the target common voltage to a common wire in the signal transmission wires.

3. The touch display control circuit according to claim 2, wherein the touch detection circuits are plural, each common trace is connected to common electrode signal selection sub-circuits, and each common electrode signal selection sub-circuit is connected to any touch detection circuits.

4. The touch display control circuit according to claim 2, wherein each of the common traces is connected to of the common electrode signal selection sub-circuits, and each of the common electrode signal selection sub-circuits is connected to of the touch detection circuits.

5. The touch display control circuit according to claim 2, wherein the signal selection circuit comprises a plurality of switches, and a control terminal of each switch is connected to the display control timing sequence or the display touch control timing sequence to gate a preset control voltage to the signal transmission traces.

6. The touch display control circuit according to claim 5, wherein the number of the touch detection circuits is plural, each of the common traces is connected to of the signal selection circuits, and each of the signal selection circuits is connected to any of the touch detection circuits.

7. The touch display control circuit according to claim 5, wherein each of the common traces is connected to of the signal selection circuits, and each of the signal selection circuits is connected to of the touch detection circuits.

8. The touch display control circuit of claim 1, wherein the touch detection circuit comprises: an amplifier and a plurality of switches;

the amplifier is used for detecting the change value of the self-capacitance of the common electrode and outputting a voltage signal corresponding to the change value of the self-capacitance.

control methods applied to the touch display control circuit of claim 1, the control method including controlling the display driving circuit to be in an on state, controlling the touch detection circuit to be in an isolated state, and gating a preset control voltage to cause the display driving circuit to output the preset control voltage to the signal transmission traces during a display timing segment based on the display control timing;

and in the display touch control time sequence section, controlling the touch control detection circuit to perform touch control detection based on the display touch control time sequence.

10. The method of claim 9, wherein the display touch timing segment comprises a th phase and a second phase;

stage , the display driving circuit is in on state, the touch detection circuit is in isolation and self-correction state;

and in the second stage, the touch detection circuit is in a detection state.

11. The method according to claim 9, wherein the display control timing and the display touch control timing are executed according to a preset rule;

the preset rules include: the display control time sequence is executed alternately for m times continuously and the display touch control time sequence for n times continuously; wherein m is an integer greater than or equal to 0; and n is an integer greater than or equal to 1.

12, kinds of electronic equipment, characterized by, including the electronic equipment body and the touch-sensitive display control circuit of any in claims 1-8.

Technical Field

The invention relates to the technical field of semiconductors, in particular to touch display control circuits, control methods and electronic equipment.

Background

With the continuous development of technology, the LCD panel with touch function has become a great trend of electronic devices, and at present, the capacitive touch technology is widely applied to the TFT-LCD panel.

The brightness and dynamic response speed of liquid crystal screens such as STN-LCD, TN-LCD and CSTN-LCD are lower than those of TFT-LCD, but the liquid crystal screens such as STN-LCD are still widely applied to electronic equipment by due to the advantage of low cost, and if touch screens are selected to be attached to the low-cost liquid crystal screens, the display effect of the integrated liquid crystal screens is poor and the cost is increased.

Therefore, how to provide touch display circuits can enable the STN-LCD, TN-LCD and CSTN-LCD to have a touch function on the basis of not changing the structure of the original liquid crystal screen is technical problems to be broken through by the technical personnel in the field.

Disclosure of Invention

In view of this, the invention provides touch display control circuits, control methods and electronic devices, which can make the STN-LCD, TN-LCD and CSTN-LCD liquid crystal panels have touch functions without changing the original liquid crystal screen structure.

In order to achieve the purpose, the invention provides the following technical scheme:

kinds of touch display control circuit, which is used to drive the liquid crystal screen, the touch display control circuit includes:

the display driving circuit comprises a signal transmission line, a signal selection circuit and a reference voltage generation circuit, wherein the signal transmission line is used for transmitting a grid signal and a public signal, the signal selection circuit gates a preset control voltage based on a display control time sequence or a display touch control time sequence, and the reference voltage generation circuit is connected with the signal selection circuit and used for providing the preset control voltage;

and the touch detection circuit is connected with the signal selection circuit and is used for performing touch detection based on the display touch control time sequence.

Optionally, the signal selection circuit includes:

the grid signal selection sub-circuit is connected with the reference voltage generation circuit, gates a target grid voltage based on the display control time sequence and transmits the target grid voltage to the grid wires in the signal transmission wires;

and the common electrode signal selection sub-circuit is connected with the reference voltage generation circuit, gates a target common voltage based on the display control time sequence or the display touch control time sequence, and transmits the target common voltage to a common wire in the signal transmission wires.

Optionally, the number of the touch detection circuits is multiple, each common trace is connected to common electrode signal selection sub-circuits, and each common electrode signal selection sub-circuit is connected to any touch detection circuits.

Optionally, each common trace is connected to common electrode signal selection sub-circuits, and each of the common electrode signal selection sub-circuits is connected to touch detection circuits.

Optionally, the signal selection circuit includes a plurality of switches, and a control end of each switch is connected to the display control timing sequence or the display touch control timing sequence to gate a preset control voltage to the signal transmission trace.

Optionally, the number of the touch detection circuits is multiple, each common trace is connected to signal selection circuits, and each signal selection circuit is connected to any touch detection circuits.

Optionally, each common trace is connected to signal selection circuits, and each of the signal selection circuits is connected to touch detection circuits.

Optionally, the touch detection circuit includes: an amplifier and a plurality of switches;

the amplifier is used for detecting the change value of the self-capacitance of the common electrode and outputting a voltage signal corresponding to the change value of the self-capacitance.

control methods, applied to the touch display control circuit, the control method includes controlling the display driving circuit to be in an on state, controlling the touch detection circuit to be in an isolated state, and gating a preset control voltage to enable the display driving circuit to output the preset control voltage to the signal transmission trace at a display time period based on the display control time sequence;

and in the display touch control time sequence section, controlling the touch control detection circuit to perform touch control detection based on the display touch control time sequence.

Optionally, the display touch timing segment includes th stage and a second stage;

stage , the display driving circuit is in on state, the touch detection circuit is in isolation and self-correction state;

and in the second stage, the touch detection circuit is in a detection state.

Optionally, the display control timing sequence and the display touch control timing sequence are executed according to a preset rule;

the preset rules include: the display control time sequence is executed alternately for m times continuously and the display touch control time sequence for n times continuously; wherein m is an integer greater than or equal to 0; and n is an integer greater than or equal to 1.

kinds of electronic equipment comprises an electronic equipment body and any items of the touch display control circuit.

Compared with the prior art, the technical scheme provided by the invention has the following advantages:

the invention provides touch display control circuits, which are used for driving liquid crystal screens of STN-LCDs, TN-LCDs and CSTN-LCDs and comprise display driving circuits and touch detection circuits, wherein each display driving circuit comprises signal transmission wires, a plurality of groups of signal selection circuits and a reference voltage generation circuit, the signal transmission wires are used for transmitting grid signals and common signals, the signal selection circuits gate preset control voltages based on display control time sequences or display touch control time sequences, and the reference voltage generation circuits provide the preset control voltages.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a driving waveform diagram of a prior art STN-LCD panel;

FIG. 2 is a schematic diagram of the waveforms of FIG. 1 plotted at ;

FIG. 3 is a schematic diagram of a prior art STN-LCD display driving circuit;

fig. 4 is a schematic diagram illustrating a driving principle of the touch circuit 200;

FIG. 5 is a schematic diagram of touch display control circuits provided by the present invention;

FIG. 6 is a schematic view of another touch display control circuits of touch displays according to the present invention;

FIG. 7 is another schematic diagram of touch display control circuits provided by the present invention;

fig. 8 is a schematic structural diagram of electronic devices provided in this embodiment.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only partial embodiments of of the present invention, rather than all embodiments.

In combination with the background art, some conventional liquid crystal panels (such as STN-LCD, TN-LCD, CSTN-LCD, etc.) have failed to implement touch functionality, and the inventors consider that these liquid crystal panels are generally applied to low-cost electronic devices. In addition, in the prior art, a touch screen module (including a touch screen and a touch chip) is attached to the liquid crystal screens, or such liquid crystal screens can have a touch function. However, the screen-attaching method will reduce the display effect of the original liquid crystal screen and greatly increase the cost, which is contrary to the low-cost concept.

Based on this, taking the STN-LCD liquid crystal screen as an example, the inventor combines the display principle of the current STN-LCD liquid crystal screen to realize the touch function of the STN-LCD liquid crystal screen in a manner of not adding a touch screen. As shown in fig. 1, for the STN-LCD panel, waveforms similar to Capacitive Touch Panel (CTP) driving waveforms are usually adopted for driving, wherein waveforms symmetrical to each other are selected in odd number timing (ODDFRAME) and even number timing (EVEN FRAME), so as to eliminate the adverse effect of the dc component on the liquid crystal.

Specifically, taking a waveform with a control voltage of 6 levels as an example, when each common voltage is in an inactive state, the current common voltage is set to be the second preset voltage V1, and when the common voltage is in an active state, the current common voltage is set to be the sixth preset voltage V5., and then signal changes are performed between the common voltages transmitted by different common lines according to a time interval of .

In the present embodiment, the gate voltage is set to have the second preset voltage V1 as the middle data, the third preset voltage V2 as the high voltage of the gate voltage, and the th preset voltage V0 as the low voltage of the gate voltage.

The waveforms of the common voltage and the gate voltage in fig. 1 are plotted at at the same time point , and a waveform curve as shown in fig. 2 is presented, in which a black bold line is the waveform of the common voltage, and a diamond structure is the waveform range of the gate voltage, that is, the gate voltage is the third preset voltage V2 or the th preset voltage V0.

On the basis of the above embodiment, the voltage selection of the common voltage may be implemented by the driving circuit shown in fig. 3, for example, when the switch 31 is closed, the common voltage com (i) is the sixth preset voltage V5, and when the switch 33 is closed, the common voltage com (i) is the second preset voltage V1.

Specifically, each common traces com (i) correspond to switch groups 111(i), where i is a positive integer greater than or equal to 1, and correspondingly, each gate traces seg (j) corresponds to switch groups 121(j), where j is also a positive integer greater than or equal to 1, and then the on and off states of the switches in the switch groups 111(i) are controlled by the time sequence 112(i), and the on and off states of the switches in the switch groups 121(j) are controlled by the time sequence 122(j), so that the corresponding common voltage and the gate voltage are output.

Illustratively, referring to fig. 3, the switch group 111(i) includes a switch 31, a switch 32, a switch 33, and a switch 34, specifically, the terminal of the switch 31 is connected to the sixth preset voltage V5, the terminal of the switch 32 is connected to the fifth preset voltage V4, the terminal of the switch 33 is connected to the second preset voltage V1, the terminal of the switch 34 is connected to the preset voltage V0, and the other terminal of the switch 31, the other terminal of the switch 32, the other terminal of the switch 33, and the other terminal of the switch 34 are all connected to the common trace com (i).

The switch group 121(j) includes a switch 35, a switch 36, a switch 37, and a switch 38, specifically, an terminal of the switch 35 is connected to a sixth preset voltage V5, a terminal of the switch 36 is connected to a fourth preset voltage V3, a terminal of the switch 37 is connected to a third preset voltage V2, a terminal of the switch 38 is connected to a preset voltage V0, and another terminal of the switch 35, another terminal of the switch 36, another terminal of the switch 37, and another terminal of the switch 38 are connected to the gate trace seg (j).

For example, a resistor voltage divider circuit formed by the resistor 11, the resistor 12, the resistor 13, the resistor 14, and the resistor 15 can obtain a required voltage value, and then the operational amplifier 21, the operational amplifier 22, the operational amplifier 23, and the operational amplifier 24 can provide voltages of V0, V1, V2, V3, V4, and V5.

Besides, it should be noted that, in the embodiment of the present invention, the circuit shown in 101 is located inside the chip, and the signal transmission trace 500 shown in 102 is located outside the chip (on the liquid crystal display); that is, the signal transmission traces shown in 102 are connected to the pins of the chip, and extend from the pins of the chip to the liquid crystal panel, and the trace pattern shown in 102 is formed on the liquid crystal panel. It is understood that the present embodiment is described by combining the signal transmission traces shown in the portion 102 with the display driving circuit 501 for convenience of description.

On the basis, the inventor combines the driving principle of the touch circuit 200 as shown in fig. 4, and when the timing is , the control switch 61 and the switch 62 are both open, and the control switch 64 is closed, wherein the terminal 64 of the switch 64 is connected to the second preset voltage V1, the terminal of the switch 64 is connected to the non-inverting input terminal 41 of the amplifier 50, the terminal of the switch 60 is connected to the inverting input terminal of the amplifier 50, and the terminal of the switch 60 is connected to the output terminal of the touch circuit.

At this time, the switch 60 is closed, the amplifier 50 performs an auto clear operation, the charge amount Q (C51) on the capacitor 51 becomes 0, and the output terminal voltage Vo of the touch circuit becomes V1.

The switches 71 and 73 are closed, the switch 72 is opened, the upper end of the capacitor 70 is connected to the voltage VDD, and the lower end is grounded to store the preset charge.

Meanwhile, the common trace COM is connected to the sixth preset voltage V5, and the precharge operation is performed , as can be seen, the sum of the charge amounts of the three circuits in fig. 4 is Q1 ═ 0+ C70 ═ VDD + Cself × V5, where Cself is the self capacitance of the common electrode.

When in the second timing, both the control switch 61 and the switch 62 are closed.

At this time, the switch 60 is turned off, and the amplifier 50 performs a detection operation.

The switches 71 and 73 are opened, the switch 72 is closed, and the lower end of the capacitor 70 is connected to the voltage VDD.

At this time, the potential of COM is maintained at the second preset voltage V1 due to the virtual ground of the amplifier 50.

It can be seen that the sum of the charge amounts of the three-part circuit in fig. 4 is Q2 ═ C51 ═ C1-Vo) + C70 ═ V1-VDD) + Cself ═ V1.

Since Q2 is Q1, the output voltage Vo of the touch circuit is V1+ C70/C51 (V1-2 VDD) + Cself/C51 (V1-V5). Cself is original self capacitance, and when there is the finger touch, can bring capacitance variation Cfinger, Cself will become Cself' ═ Cself + Cfinger, and no longer repeated here.

Therefore, based on the circuit, the detection of the touch event can be realized by detecting the change of the voltage at the output end of the amplifier.

The inventor integrates the touch control circuit and the driving circuit, as shown in fig. 5, an embodiment of the invention provides touch control display control circuits, which are applied to driving a liquid crystal display, and include a display driving circuit 501 and a touch control detecting circuit 502.

The display driving circuit 501 includes a signal transmission trace 500, a signal selection circuit (504 and 121(j)), and a reference voltage generation circuit 503, where the signal transmission trace 500 is used to transmit a gate signal and a common signal, the signal selection circuit (504 and 121(j)) gates a preset control voltage based on a display control timing 122(j) or a display touch control timing 132(i), and the reference voltage generation circuit 503 is connected to the signal selection circuit (504 and 121(j)) and is used to provide the preset control voltage. The touch detection circuit 502 is connected to the signal selection circuit 504, and performs touch detection based on a display touch control timing.

Therefore, the touch display control circuit provided by the scheme combines the display driving circuit and the touch detection circuit, and can enable the original liquid crystal screen to have a touch function on the basis of not changing the structure of the original liquid crystal screen.

Specifically, the signal selection circuit provided in this embodiment has a plurality of implementation manners, and referring to fig. 5, the signal selection circuit provided in this embodiment includes:

a gate signal selection sub-circuit 121(j) connected to the reference voltage generation circuit 503, gating a target gate voltage based on the display control timing 122(j), and transmitting the target gate voltage to a gate trace SEG among the signal transmission traces;

the common electrode signal selection sub-circuit 504 is connected to the reference voltage generation circuit 503, gates a target common voltage based on the display control timing 122(j) or the display touch control timing 132(i), and transmits the target common voltage to the common line COM in the signal transmission line 500.

It is worth mentioning that , as shown in fig. 5, the touch display circuit provided in this embodiment includes a plurality of touch detection circuits 502, specifically, each common trace com (i) is connected to common electrode signal selection sub-circuits 504, and each common electrode signal selection sub-circuit 504 is connected to touch detection circuits 502.

That is, in this embodiment, the number of the common electrode signal selection sub-circuits 504 is the same as that of the touch detection circuits 502, and the -th circuit 131(i) is composed of the common electrode signal selection sub-circuits 504 and the touch detection circuits 502.

On the basis of the foregoing embodiments, the embodiment of the present invention further provides specific implementation structures of the common electrode signal selection sub-circuit 504 and the gate signal selection sub-circuit 121(j), where the common electrode signal selection sub-circuit 504 includes a th switch 31, a second switch 32, a third switch 33, and a fourth switch 34, and the gate signal selection sub-circuit 121(j) includes a fifth switch 35, a sixth switch 36, a seventh switch 37, and an eighth switch 38;

specifically, the th end of the th switch 31, the th end of the second switch 32, the th end of the third switch 33, and the th end of the fourth switch 34 are all connected to common trace com (i);

a second end of the switch 31, a second end of the second switch 32, a second end of the third switch 33, and a second end of the fourth switch 34 are sequentially connected to the sixth preset voltage V5, the fifth preset voltage V4, the second preset voltage V1, and the preset voltage V0;

the control terminal of the th switch 31, the control terminal of the second switch 32, the control terminal of the third switch 33, and the control terminal of the fourth switch 34 are all connected to the display control timing 122(j) or the display touch control timing 132 (i);

the th terminal of the fifth switch 35, the th terminal of the sixth switch 36, the th terminal of the seventh switch 37 and the th terminal of the eighth switch 38 are all connected to gate traces seg (j);

the second terminal of the fifth switch 35, the second terminal of the sixth switch 36, the second terminal of the seventh switch 37 and the second terminal of the eighth switch 38 are sequentially connected to the sixth preset voltage V5, the fourth preset voltage V3, the third preset voltage V2 and the preset voltage V0.

The control end of the fifth switch, the control end of the sixth switch, the control end of the seventh switch, and the control end of the eighth switch are all connected to the display control timing sequence 122 (j).

It should be noted that, in the present embodiment, there are a plurality of touch detection circuits, and besides, there may be only touch detection circuits, for example, in fig. 6, each common trace com (i) is connected to common electrode signal selection sub-circuits 601, and a plurality of common electrode signal selection sub-circuits 601 are connected to touch detection circuits 602.

Specifically, the embodiment of the present invention further provides specific implementation structures of the common electrode signal selection sub-circuit 601 and the gate signal selection sub-circuit 603, where the common electrode signal selection sub-circuit 601 includes a ninth switch 31 ', a tenth switch 32 ', a tenth switch 33 ', a twelfth switch 34 ', and a thirteenth switch 35 ', and the gate signal selection sub-circuit 603 includes a fourteenth switch 36 ', a fifteenth switch 37 ', a sixteenth switch 38 ', and a seventeenth switch 39 '.

Specifically, the th end of the ninth switch 31 ', the th end of the tenth switch 32 ', the th end of the tenth switch 33 ', the th end of the twelfth switch 34 ' and the th end of the thirteenth switch 35 ' are all connected to common traces com (i);

a second end of the ninth switch 31 ', a second end of the tenth switch 32', a second end of the tenth switch 33 'and a second end of the twelfth switch 34' are sequentially connected to the sixth preset voltage V5, the fifth preset voltage V4, the second preset voltage V1 and the preset voltage V0;

the control end of the ninth switch 31 ', the control end of the tenth switch 32', the control end of the tenth switch 33 'and the control end of the twelfth switch 34' are all connected to the display control timing or the display touch control timing;

a second end of the thirteenth switch 35' is connected to the touch detection circuit 602;

the th end of the fourteenth switch 36 ', the th end of the fifteenth switch 37', the th end of the sixteenth switch 38 'and the th end of the seventeenth switch 39' are all connected to gate traces seg (j);

a second end of the fourteenth switch 36 ', a second end of the fifteenth switch 37', a second end of the sixteenth switch 38 'and a second end of the seventeenth switch 39' are sequentially connected to the sixth preset voltage V5, the fourth preset voltage V3, the third preset voltage V2 and the preset voltage V0.

The control end of the fourteenth switch 36 ', the control end of the fifteenth switch 37', the control end of the sixteenth switch 38 'and the control end of the seventeenth switch 39' are all connected to the display control timing sequence.

On the basis of the foregoing embodiments, the embodiment of the present invention further provides a specific implementation structure of signal selection circuits, as shown in fig. 7, the signal selection circuit 151(i) includes a plurality of switches, and a control end of each switch can be connected to the display control timing sequence or the display touch control timing sequence to gate a preset control voltage to the signal transmission trace 500.

Specifically, the signal selection circuit includes an eighteenth switch 311, a nineteenth switch 321, a twentieth switch 331, a twentieth switch 341, a twenty-second switch 351, a twentieth switch 361, and a twenty-fourth switch 371;

the th end of the eighteenth switch 311, the th end of the nineteenth switch 321, the th end of the twentieth switch 331, the th end of the twentieth switch 341, the th end of the twenty-second switch 351, the th end of the twentieth switch 361, and the th end of the twenty-fourth switch 371 are all connected to the common trace com (i) of or the gate trace seg (j) of ;

the second end of the eighteenth switch 311, the second end of the nineteenth switch 321, the second end of the twentieth switch 331, the second end of the twentieth switch 341, the second end of the twenty-second switch 351, the second end of the twentieth switch 361, and the second end of the twenty-fourth switch 371 are sequentially connected to the sixth preset voltage V5, the fifth preset voltage V4, the fourth preset voltage V3, the third preset voltage V2, the second preset voltage V1, and the preset voltage V0;

the control end of the eighteenth switch 311, the control end of the nineteenth switch 321, the control end of the twentieth switch 331, the control end of the twentieth switch 341, the control end of the twenty-second switch 351, and the control end of the twentieth switch 361 are all connected to the display control timing or the display touch control timing 152 (i);

a second end of the twenty-fourth switch 371 is connected to the touch detection circuit 702.

Similarly, in the present embodiment, each signal selection circuit 151(i) may correspond to touch detection circuits 702, or a plurality of signal selection circuits 151(i) correspond to touch detection circuits 702, such that:

the number of the touch detection circuits 702 is plural, each common trace com (i) is connected to signal selection circuits 151(i), and each signal selection circuit 151(i) is connected to any touch detection circuits 702.

Or the like, or, alternatively,

each of the common traces com (i) is connected to signal selection circuits 151(i), and each of the signal selection circuits 151(i) is connected to touch detection circuits 702.

On the basis of the above embodiments, with reference to fig. 5 to 7, the embodiment of the present invention further provides specific implementation structures of the reference voltage generating circuit (503 or 603), including a resistor 11, a second resistor 12, a third resistor 13, a fourth resistor 14, a fifth resistor 15, a amplifier 21, a second amplifier 22, a third amplifier 23, and a fourth amplifier 24.

Specifically, the end of the th resistor 11 serves as the output end of the th preset voltage V0;

a second terminal of the th resistor 11 is respectively connected to the non-inverting input terminal of the th amplifier 21 and the th terminal of the second resistor 12, and an inverting input terminal of the th amplifier 21 is connected to the output terminal of the th amplifier 21 and serves as an output terminal of the second preset voltage V1;

a second end of the second resistor 12 is connected to a non-inverting input terminal of the second amplifier 22 and a th end of the third resistor 13, respectively, and an inverting input terminal of the second amplifier 22 is connected to an output terminal of the second amplifier 22 and serves as an output terminal of the third preset voltage V2;

a second end of the third resistor 13 is connected to a non-inverting input terminal of the third amplifier 23 and a th end of the fourth resistor 14, respectively, and an inverting input terminal of the third amplifier 23 is connected to an output terminal of the third amplifier 23 and serves as an output terminal of the fourth preset voltage V3;

a second end of the fourth resistor 14 is connected to a non-inverting input terminal of the fourth amplifier 24 and a th end of the fifth resistor 15, respectively, and an inverting input terminal of the fourth amplifier 24 is connected to an output terminal of the fourth amplifier 24 and serves as an output terminal of the fifth preset voltage V4;

the required voltage value can be obtained through the resistor voltage dividing circuit formed by the resistor 11, the resistor 12, the resistor 13, the resistor 14 and the resistor 15, and then the voltages of V0, V1, V2, V3, V4 and V5 can be provided through the operational amplifier 21, the operational amplifier 22, the operational amplifier 23 and the operational amplifier 24.

It should be noted again that, in each embodiment of the present invention, the circuit shown in 101 is located inside the chip, and the signal transmission trace 500 shown in 102 is located outside the chip (on the liquid crystal display); that is, the signal transmission traces shown in 102 are connected to the pins of the chip, and extend from the pins of the chip to the liquid crystal panel, and the trace pattern shown in 102 is formed on the liquid crystal panel. It is understood that the present embodiment is described by combining the signal transmission traces shown in the portion 102 with the display driving circuit 501 for convenience of description.

Specifically, the embodiment of the invention also provides a specific implementation circuit of touch detection circuits, wherein the touch detection circuit comprises an amplifier and a plurality of switches;

the amplifier is used for detecting the change value of the self-capacitance of the common electrode and outputting a voltage signal corresponding to the change value of the self-capacitance.

Specifically, referring to fig. 5, the touch detection circuit may include a th capacitor 51, a second capacitor 52, a fifth amplifier 50, a twenty-fifth switch 60, a twenty-sixth switch 61, a twenty-seventh switch 62, a twenty-eighteenth switch 63, and a twenty-ninth switch 64.

Specifically, two ends of the twenty-fifth switch 60 and the th capacitor 51 are connected in parallel to the inverting input end and the output end of the fifth amplifier 50, and the output end of the fifth amplifier 50 is used as the output end of the touch detection circuit 502;

the inverting input terminal of the fifth amplifier 50 is connected to the signal selection circuit 131(i) through a twenty-sixth switch 61, and the signal selection circuit 131(i) is connected to the second capacitor 52 through the twenty-seventh switch 62;

the non-inverting input terminal of the fifth amplifier 50 is connected to the fifth preset voltage V4 through the twenty-eighth switch 63 and to the second preset voltage V1 through the twenty-ninth switch 64.

With the above circuit structure, the operation principle of the present solution will now be described as follows:

and in a display time sequence section, based on the display control time sequence, controlling the display driving circuit to be in an open state, controlling the touch detection circuit to be in an isolation and automatic correction state, and gating a preset control voltage so that the display driving circuit outputs the preset control voltage to the signal transmission wiring.

Specifically, the th switch 31 may be controlled to be closed, so that the common trace COM (i) is connected to the sixth preset voltage V5, that is, the common voltage COM in the active state is V5 at this time, and the twenty-seventh switch 62 is controlled to be closed, so that the second capacitor 52 stores the preset charge, and the twenty-ninth switch 64 is controlled to be closed, so that the second preset voltage V1 is connected to the non-inverting input terminal of the fifth amplifier 50, so that the fifth amplifier 50 performs the auto-zero operation.

In the display touch control time sequence, the touch control detection circuit 502 is controlled to perform touch control detection based on the display touch control time sequence.

Specifically, the display touch timing segment includes an th stage and a second stage;

at stage , the display driver circuit 501 is turned on and the touch detection circuit 502 is isolated and self-calibrated, at this time, the inverting input terminal of the fifth amplifier 50 in the touch detection circuit 502 is connected to the output terminal, so that the output terminal of the fifth amplifier 50 is maintained at a specific voltage value, such as the second predetermined voltage V1.

In the second stage, the touch detection circuit 502 is in a detection state. At this time, the common voltage com (i) is connected to the inverting input terminal of the fifth amplifier 50, and due to the virtual ground effect when the fifth amplifier 50 operates normally, the voltage at the inverting input terminal of the fifth amplifier 50 is the same as the voltage at the non-inverting input terminal, and at this time, the non-inverting input terminal of the fifth amplifier 50 is connected to an appropriate potential, so that the potential on the common line com (i) can be maintained at the above-mentioned specific voltage value, such as the second preset voltage V1, and at this time, the normal display function can be maintained and the capacitance detection function can be performed.

Illustratively, the th switch 31, the second switch 32, the third switch 33, the fourth switch 34, the fifth switch 35, the sixth switch 36, the seventh switch 37, and the eighth switch 38 may be controlled to be opened, and the twenty-fifth switch 60, the twenty-sixth switch 61, the twenty-seventh switch 62, and the twenty-ninth switch 64 may be controlled to be closed, so that the touch detection circuit outputs the target voltage based on the touch action.

Therefore, the touch display control circuit provided by the scheme can enable the STN-LCD, TN-LCD and CSTN-LCD to have a touch function on the basis of not changing the structure of the original liquid crystal screen.

On the basis of the above embodiments, as shown in fig. 8, the present embodiment further provides electronic devices, which include an electronic device body and any of the above touch display control circuits.

In summary, the present invention provides touch display control circuits, control methods and electronic devices, wherein the control circuits are used for driving STN-LCD, TN-LCD and CSTN-LCD liquid crystal screens, and comprise display driving circuits and touch detection circuits, wherein the display driving circuits comprise signal transmission lines, multiple groups of signal selection circuits and reference voltage generation circuits, the signal transmission lines are used for transmitting gate signals and common signals, the signal selection circuits gate preset control voltages based on display control time sequences or display touch control time sequences, the reference voltage generation circuits provide preset control voltages, the touch detection circuits are connected with the multiple groups of signal selection circuits, and touch signals to be tested are detected based on the display touch control time sequences.

The foregoing description of the disclosed embodiments will enable those skilled in the art to make or use the invention, it being understood that various modifications to these embodiments will be readily apparent to those skilled in the art, that the general principles of as defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention, and that the invention is not to be limited to the embodiments illustrated herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.