Touch chip, touch device, touch screen and electronic equipment

Abstract

The utility model discloses a touch chip, a touch device, a touch screen and electronic equipment. The touch control chip is used for being connected with a touch control screen, and the touch control screen comprises a common voltage line and at least two touch control units. Each touch unit comprises a touch electrode, a function change-over switch and a control circuit; the first end of each touch electrode is connected with a common voltage line through a function change-over switch; each control circuit is connected with a control end of the function change-over switch and a connecting node between the function change-over switch and the touch electrode; the common voltage end is connected with a common voltage line; the coding signal end is connected with the second ends of the at least two touch electrodes; and the control signal end is connected with the control circuit and is used for outputting a control signal to the control circuit, so that the control circuit controls the function change-over switch to be turned on or turned off. The touch chip can adjust the potential of the control end of the function change-over switch based on the coding potential change in the coding process of the touch screen so as to achieve a TSP function mode and an EMR function mode.

Description

Technical Field

[0001] The utility model relates to the technical field of touch control, in particular to a touch control chip, a touch control device, a touch screen and an electronic device. Background Art

[0002] In order to enable a touch screen to support not only finger touch operations but also stylus touch operations, the existing touch screen can use the film layer of a capacitive touch screen (touch screen panel, hereinafter referred to as TSP) as the wire of an electromagnetic touch screen (Electro magnetic Resonance, hereinafter referred to as EMR), and a function switching switch is provided. The function switching switch is used to connect a touch electrode and a common voltage line. When the function switching switch is closed, the touch screen can enter the TSP function mode. When the function switching switch is open, the touch screen can enter the EMR function mode. As a function switching switch for distinguishing the TSP function mode and the EMR function mode, a fixed voltage is generally output through a touch control chip to control the function switching switch to be opened or closed. In the process of coding the touch screen, this method causes large voltage fluctuations at both ends of the function switching switch, affecting the normal operation of the touch screen. Summary of the Utility Model

[0003] Embodiments of the utility model provide a touch control chip, a touch control device, a touch screen and an electronic device to solve the problem that the voltage at both ends of the function switching switch provided between the touch electrode and the common voltage line fluctuates greatly during the coding process of the touch screen, affecting the normal operation of the touch screen.

[0004] A touch control chip is used to connect to a touch screen. The touch screen includes a common voltage line and at least two touch units; each touch unit includes a touch electrode, a function switching switch and a control circuit; the first end of each touch electrode is connected to the common voltage line through a function switching switch; each control circuit is connected to the control end of the function switching switch and the connection node between the function switching switch and the touch electrode;

[0005] The touch control chip includes a common voltage terminal, a coding signal terminal and a control signal terminal;

[0006] The common voltage terminal is connected to the common voltage line;

[0007] The coding signal terminal is connected to the second ends of at least two touch electrodes;

[0008] The control signal terminal is connected to the control circuit, and the control signal terminal is used to output a control signal to the control circuit so that the control circuit controls the function switching switch to be opened or closed.

[0009] Preferably, each of the control circuits includes a first capacitor and a switch circuit; one end of the first capacitor is connected to the control end of the function switching switch, and the other end of the first capacitor is connected to the connection node between the function switching switch and the touch electrode; the second end of the switch circuit is connected to the control end of the function switching switch;

[0010] The control signal terminal includes a reference voltage terminal and a switch signal terminal. The reference voltage terminal is connected to the first end of the switch circuit, and the switch signal terminal is connected to the third end of the switch circuit;

[0011] The switch signal terminal outputs a control signal to the switch circuit to turn the switch circuit on or off, and the reference voltage terminal outputs a reference voltage to the switch circuit. Based on the reference voltage, the function switching switch is controlled to be turned on or off.

[0012] Preferably, the common voltage terminal is connected to the common voltage line through a state switch;

[0013] The reference voltage includes a first reference voltage for controlling the function switching switch to close;

[0014] The switch signal terminal is used to output a first control signal to the switch circuit to turn the switch circuit on, and the reference voltage terminal is used to output the first reference voltage to the switch circuit to control the function switching switch to close and initialize the potential of the control end of the function switching switch;

[0015] The switch signal terminal is used to output a second control signal to the switch circuit to turn the switch circuit off, keep the function switching switch in the off state, and make the potential of the control end of the function switching switch follow the coding potential change of the touch electrode;

[0016] When the state switch is in the on state, the common voltage terminal is used to output a common voltage to the common voltage line, and the coding signal terminal is used to output a first coding signal to the touch electrode to make the touch screen enter the TSP function mode.

[0017] Preferably, the reference voltage includes a second reference voltage for controlling the switch circuit to close;

[0018] When the switch signal terminal is used to output a second control signal to the switch circuit, the reference voltage terminal outputs the second reference voltage to the switch circuit to keep the switch circuit in the off state.

[0019] Preferably, the coding signal terminal is used to output a first coding signal to at least two of the touch electrodes simultaneously.

[0020] Preferably, the common voltage terminal is connected to the common voltage line through a state switch;

[0021] The reference voltage includes a third reference voltage for controlling the opening of the function switching switch;

[0022] The switch signal terminal is used to output a first control signal to the switch circuit to turn on the switch circuit, and the reference voltage terminal is used to output the third reference voltage to the switch circuit to control the opening of the function switching switch;

[0023] When the state switch is in the off state, the coding signal terminal is used to output a second coding signal to the touch electrode to enable the touch screen to enter the EMR function mode.

[0024] Preferably, the common voltage line includes a first common voltage line connected to at least three touch electrodes;

[0025] The coding signal terminal is used to output a second coding signal to each of the at least three touch electrodes corresponding to the same first common voltage line one by one.

[0026] Preferably, the common voltage line includes a second common voltage line connected to two touch electrodes;

[0027] The coding signal terminal is used to output a second coding signal to the two touch electrodes corresponding to the same second common voltage line simultaneously.

[0028] Preferably, the switch circuit includes a first control switch, and the second end of the first control switch is connected to the control end of the function switching switch;

[0029] The reference voltage terminal is connected to the first end of the first control switch, and the switch signal terminal is connected to the control end of the first control switch;

[0030] The switch signal terminal outputs a first control signal to the first control switch to turn on the first control switch, or outputs a second control signal to the first control switch to turn off the first control switch.

[0031] Preferably, the switch circuit further includes a voltage boosting circuit, and the voltage boosting circuit is connected to the connection node between the second end of the first control switch and the control end of the function switching switch;

[0032] The control signal terminal is further used to be connected to the voltage boosting circuit to output a control signal in a second voltage range to the voltage boosting circuit, so that the voltage boosting circuit boosts the control signal in the second voltage range and converts it into a control signal in a first voltage range to control the opening or closing of the function switching switch.

[0033] Preferably, the voltage boosting circuit includes a second control switch, a third control switch, a fourth control switch, a fifth control switch, and a second capacitor; the second control switch, the third control switch, and the fourth control switch are connected in series in sequence, and the fourth control switch is connected to the control end of the function switching switch; the second end of the fifth control switch is connected to the connection node between the third control switch and the fourth control switch, and the control end of the fifth control switch is connected to the control end of the fourth control switch; the two ends of the second capacitor are respectively connected to the second end of the fifth control switch and the control end of the fifth control switch;

[0034] The switch signal terminal includes a first switch signal terminal and a second switch signal terminal; the control signal terminal further includes an input terminal, a negative voltage supply terminal, and a clock signal terminal;

[0035] The first switch signal terminal is used to connect to the control end of the first control switch to output a first switch signal to the first control switch; the second switch signal terminal is used to connect to the control end of the second control switch to output a second switch signal to the second control switch; the input terminal is used to connect to the first end of the second control switch to output a first voltage to the second control switch; the negative voltage supply terminal is used to connect to the control end of the third control switch to output a VEE voltage to the third control switch; the clock signal terminal is used to connect to the first end of the fifth control switch to output a second voltage to the fifth control switch; based on the first switch signal, the second switch signal, the first voltage, the VEE voltage, and the second voltage, control the voltage boosting circuit to boost the voltage.

[0036] Preferably, the first switch signal terminal is used to output a first control signal to the first control switch to turn on the first control switch, and the reference voltage terminal is used to output a first reference voltage to the first control switch to turn off the function switching switch;

[0037] The second switch signal terminal is used to output a first control signal to the second control switch to turn on the second control switch, the input terminal is used to output a VDD voltage to the second control switch, and the clock signal terminal is used to output a GND voltage to the fourth control switch to turn off the fourth control switch and the fifth control switch.

[0038] Preferably, the first switch signal terminal is used to output a first control signal to the first control switch to turn on the first control switch, and the reference voltage terminal is used to output a VEE voltage to the first control switch to turn on the function switching switch;

[0039] The second switch signal terminal is used to output a first control signal to the second control switch to turn on the second control switch. The input terminal outputs a VEE voltage to the second control switch, and the clock signal terminal outputs a GND voltage to the fifth control switch to turn off the fourth control switch and turn on the fifth control switch.

[0040] The first switch signal terminal is used to output a second control signal to the first control switch to turn off the first control switch. The second switch signal terminal is used to output a second control signal to the second control switch to turn off the second control switch. The clock signal terminal outputs a VEE voltage to the fifth control switch to turn on the fourth control switch and the fifth control switch.

[0041] Preferably, the touch chip is used to output a control signal within a first voltage range to the control circuit to control the control circuit to turn on or off the function switching switch.

[0042] A touch device includes the above touch chip and a status switch;

[0043] One end of the status switch is connected to the common voltage terminal of the touch chip, and the other end of the status switch is used to connect to the common voltage line of the touch screen.

[0044] Preferably, the touch device further includes a coding circuit;

[0045] One end of the coding circuit is connected to the coding signal terminal of the touch chip, and the other end of the coding circuit is used to connect to the touch electrode of the touch screen.

[0046] Preferably, the touch device further includes a power rail. One end of the power rail is connected to the control signal terminal of the touch chip, and the other end of the power rail is used to connect to the control circuit of the touch screen;

[0047] The touch chip is used to output a control signal within a second voltage range;

[0048] The power rail is used to convert the control signal within the second voltage range and output a control signal within the first voltage range to the control circuit to control the control circuit to turn on or off the function switching switch.

[0049] A touch screen is used to connect to a touch chip and includes a common voltage line and at least two touch units;

[0050] Each touch unit includes a touch electrode, a function switching switch, and a control circuit;

[0051] The first end of each of the touch electrodes is connected to the common voltage line through one of the function switching switches, and the second end of each of the touch electrodes is used to connect to the coding signal terminal of the touch chip; the common voltage line is used to connect to the common voltage terminal of the touch chip;

[0052] Each of the control circuits is connected to the control terminal of the function switching switch and the connection node between the function switching switch and the touch electrode, and is also used to connect to the control signal terminal of the touch chip, and is used to control the function switching switch to open or close according to the control signal output from the control signal terminal.

[0053] Preferably, each of the control circuits includes a first capacitor and a switch circuit;

[0054] One end of the first capacitor is connected to the control terminal of the function switching switch, and the other end of the first capacitor is connected to the connection node between the function switching switch and the touch electrode;

[0055] The first end of the switch circuit is used to connect to the reference voltage terminal of the touch chip, the second end of the switch circuit is connected to the control terminal of the function switching switch, and the third end of the switch circuit is used to connect to the switch signal terminal of the touch chip;

[0056] The switch circuit is used to open or close based on the control signal output from the switch signal terminal, and to control the function switching switch to open or close based on the reference voltage output from the reference voltage terminal.

[0057] Preferably, the common voltage line is connected to the common voltage terminal through a state switch;

[0058] The reference voltage includes a first reference voltage for controlling the function switching switch to close;

[0059] The switch circuit is used to open based on the first control signal output from the switch signal terminal, and to control the function switching switch to close based on the first reference voltage output from the reference voltage terminal, and to initialize the potential of the control terminal of the function switching switch;

[0060] The switch circuit is also used to close based on the second control signal output from the switch signal terminal, so that the function switching switch maintains a closed state, and the potential of the control terminal of the function switching switch follows the coding potential of the touch electrode;

[0061] When the state switch is in a conducting state, the common voltage line is used to receive the common voltage output from the common voltage terminal, and the touch electrode is used to receive the first coding signal output from the coding signal terminal, so that the touch screen enters the TSP function mode.

[0062] Preferably, the reference voltage includes a second reference voltage for controlling the switch circuit to turn off;

[0063] When the switch circuit is turned off based on the second control signal output from the switch signal terminal, it is further configured to maintain the off state based on the second reference voltage output from the reference voltage terminal.

[0064] Preferably, at least two of the touch electrodes corresponding to the same common voltage line are configured to receive a first coding signal simultaneously output from the coding signal terminal.

[0065] Preferably, the common voltage line is connected to the common voltage terminal through a state switch;

[0066] The reference voltage includes a third reference voltage for controlling the function switching switch to turn on;

[0067] The switch circuit is further configured to turn on based on the first control signal output from the switch signal terminal, and control the function switching switch to turn on based on the third reference voltage output from the reference voltage terminal;

[0068] When the state switch is in the off state, the touch electrode is configured to receive a second coding signal output from the coding signal terminal, so that the touch screen enters the EMR function mode.

[0069] Preferably, the common voltage line includes a first common voltage line connected to at least three of the touch electrodes;

[0070] At least three of the touch electrodes corresponding to the same first common voltage line are configured to receive second coding signals output one by one from the coding signal terminal.

[0071] Preferably, the common voltage line includes a second common voltage line, and the second common voltage line is connected to two touch electrodes;

[0072] The two touch electrodes corresponding to the same second common voltage line are configured to receive a second coding signal simultaneously output from the coding signal terminal.

[0073] Preferably, the switch circuit includes a first control switch;

[0074] A first end of the first control switch is configured to be connected to the reference voltage terminal of the touch chip, a second end of the first control switch is connected to a control end of the function switching switch, and a control end of the first control switch is configured to be connected to the switch signal terminal of the touch chip;

[0075] The first control switch is configured to turn on based on the first control signal output from the switch signal terminal, or turn off based on the second control signal output from the switch signal terminal.

[0076] Preferably, the switch circuit further includes a voltage boosting circuit, and the voltage boosting circuit is connected to a connection node between the second end of the first control switch and the control end of the function switching switch;

[0077] The voltage boosting circuit is further configured to be connected to a control signal terminal of the touch chip, and is configured to boost a control signal in a second voltage range output from the common voltage terminal and convert it into a control signal in a first voltage range, so as to turn on or off the switch circuit.

[0078] Preferably, the voltage boosting circuit includes a second control switch, a third control switch, a fourth control switch, a fifth control switch, and a second capacitor;

[0079] The second control switch, the third control switch, and the fourth control switch are connected in series in sequence, and the fourth control switch is connected to the control end of the function switching switch;

[0080] The control end of the first control switch is configured to be connected to a first switch signal terminal of the touch chip to receive a first switch signal output from the first switch signal terminal;

[0081] The first end of the second control switch is configured to be connected to an input terminal of the touch chip to receive a first voltage output from the input terminal; the control end of the second control switch is configured to be connected to a second switch signal terminal of the touch chip to receive a second switch signal output from the second switch signal terminal;

[0082] The control end of the third control switch is configured to be connected to a negative voltage power supply terminal of the touch chip to receive a VEE voltage output from the negative voltage power supply terminal;

[0083] The first end of the fifth control switch is configured to be connected to a clock signal terminal of the touch chip, the second end of the fifth control switch is connected to a connection node between the third control switch and the fourth control switch, and the control end of the fifth control switch is connected to the control end of the fourth control switch;

[0084] Two ends of the second capacitor are respectively connected to the second end of the fifth control switch and the control end of the fifth control switch;

[0085] The voltage boosting circuit is configured to control the voltage boosting circuit to boost voltage based on the first switch signal, the second switch signal, the first voltage, the VEE voltage, and the second voltage.

[0086] Preferably, the first control switch is used to be turned on based on the first control signal output from the first switch signal terminal, and based on the first reference voltage output from the reference voltage terminal, control the function switching switch to be turned off;

[0087] The second control switch is used to be turned on based on the first control signal output from the second switch signal terminal, and based on the VDD voltage output from the input terminal and the GND voltage output from the clock signal terminal, control the fourth control switch and the fifth control switch to be turned off.

[0088] Preferably, the first control switch is used to be turned on based on the first control signal output from the first switch signal terminal, and based on the VEE voltage output from the reference voltage terminal, control the function switching switch to be turned on;

[0089] The second control switch is used to be turned on based on the first control signal output from the second switch signal terminal, transmit the VEE voltage output from the input terminal to the node between the fourth control switch and the fifth control switch, and the fifth control switch receives the GND voltage output from the clock signal terminal, so that the fourth control switch is turned off and the fifth control switch is turned on;

[0090] The first control switch is used to be turned off based on the second control signal output from the first switch signal terminal, the second control switch is used to be turned off based on the second control signal output from the second switch signal terminal, and the fifth control switch receives the VEE voltage output from the clock signal terminal, so that the fourth control switch and the fifth control switch are turned on.

[0091] An electronic device includes the above-mentioned touch chip and the above-mentioned touch screen, and the touch chip is connected to the touch screen; or, includes the above-mentioned touch device and the above-mentioned touch screen, and the touch device is connected to the touch screen.

[0092] For the above-mentioned touch chip, touch device, touch screen and electronic device, the control signal terminal of the touch chip controls the function switching switch to be turned on or off through a control circuit. Since the control circuit is not only connected to the control terminal of the function switching switch, but also connected to the connection node between the function switching switch and the touch electrode, during the coding process of the touch electrode based on the coding signal of the touch chip 11, the coding potential change of the touch electrode can be determined, and the potential of its control terminal can be adjusted based on the coding potential change to ensure the realization of the TSP function mode and the EMR function mode. Description of the Drawings

[0093] To more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments of the present utility model. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0094] Figure 1 It is a schematic diagram of the electronic device in Embodiment 1 of the present utility model;

[0095] Figure 2 It is a schematic diagram of the electronic device in Embodiment 2 of the present utility model;

[0096] Figure 3 It is a schematic diagram of the electronic device in Embodiment 3 of the present utility model;

[0097] Figure 4 It is a structural comparison diagram of the touch screen in Embodiment 3 of the present utility model and the touch screen of the prior art;

[0098] Figure 5 It is a timing diagram of the touch screen in Embodiment 3 of the present utility model entering the TSP function mode;

[0099] Figure 6 It is a simulation comparison diagram of the touch screen in Embodiment 3 of the present utility model and the touch screen of the prior art;

[0100] Figure 7 It is a circuit schematic diagram of the touch screen in Embodiment 3 of the present utility model entering the EMR function mode;

[0101] Figure 8 It is the first equivalent diagram of the touch screen in Embodiment 3 of the present utility model entering the EMR function mode;

[0102] Figure 9 It is a timing diagram of the touch screen in Embodiment 3 of the present utility model entering the EMR function mode;

[0103] Figure 10 It is the second equivalent diagram of the touch screen in Embodiment 3 of the present utility model entering the EMR function mode;

[0104] Figure 11 It is the third equivalent diagram of the touch screen in Embodiment 3 of the present utility model entering the EMR function mode;

[0105] Figure 12 It is a timing diagram of the touch screen in Embodiment 3 of the present utility model entering the TSP function mode and the EMR function mode;

[0106] Figure 13 It is a schematic diagram of the electronic device in Embodiment 4 of the present utility model;

[0107] Figure 14 It is the timing diagram of the touch screen entering the TSP function mode in Embodiment 4 of the present utility model;

[0108] Figure 15 It is a state diagram of the touch screen entering the TSP function mode in Embodiment 4 of the present utility model;

[0109] Figure 16 It is the timing diagram of the touch screen entering the EMR function mode in Embodiment 4 of the present utility model;

[0110] Figure 17 It is a state diagram of the touch screen entering the EMR function mode in Embodiment 4 of the present utility model;

[0111] Figure 18 It is another state diagram of the touch screen entering the EMR function mode in Embodiment 4 of the present utility model;

[0112] Figure 19 It is the timing diagram of the touch screen entering the TSP function mode and the EMR function mode in Embodiment 4 of the present utility model;

[0113] Figure 20 It is a schematic diagram of the electronic device in Embodiment 5 of the present utility model;

[0114] Figure 21 It is a schematic diagram of the electronic device in Embodiment 6 of the present utility model.

[0115] In the figure: 1. Touch control device; 11. Touch control chip; P1. Common voltage terminal; P2. Coding signal terminal; P3. Control signal terminal; VREF. Reference voltage terminal; SW. Switch signal terminal; SW1. First switch signal terminal; SW2. Second switch signal terminal; IN. Input terminal; VEE. Negative voltage power supply terminal; CLK. Clock signal terminal; 12. State switch; 13. Coding circuit; 14. Power rail; 2. Touch screen; 21. Common voltage line; 22. Touch control unit; 221. Function switching switch; 222. Touch control electrode; 223. Control circuit; C1. First capacitor; 2231. Switching circuit; TFT1. First control switch; 22311. Voltage boosting circuit; TFT2. Second control switch; TFT3. Third control switch; TFT4. Fourth control switch; TFT5. Fifth control switch; C2. Second capacitor. Detailed implementation manners

[0116] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0117] It should be understood that the present invention can be implemented in different forms and should not be construed as limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. In the drawings, for clarity, the dimensions and relative dimensions of layers and regions may be exaggerated. Like reference numerals throughout the drawings denote like elements.

[0118] It should be understood that when an element or layer is referred to as being "on", "adjacent to", "connected to" or "coupled to" another element or layer, it can be directly on, adjacent to, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on", "directly adjacent to", "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and / or portions, these elements, components, regions, layers and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or portion from another element, component, region, layer or portion. Thus, a first element, component, region, layer or portion discussed below may be denoted as a second element, component, region, layer or portion without departing from the teachings of the present invention.

[0119] Spatial relationship terms such as "under", "below", "lower", "beneath", "above", "upper", etc. may be used herein for convenience in describing the relationship of one element or feature shown in the drawings to another element or feature. It should be understood that, in addition to the orientation shown in the drawings, spatial relationship terms are intended to include different orientations of the device in use and operation. For example, if the device in the drawing is flipped, then an element or feature described as "under" or "beneath" or "below" another element or feature will be oriented "above" the other element or feature. Thus, the exemplary terms "under" and "beneath" can include both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatial descriptors used herein are to be interpreted accordingly.

[0120] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present utility model. When used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, identify the presence of the described features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups. When used herein, the term "and / or" includes any and all combinations of the related listed items.

[0121] To thoroughly understand the present utility model, detailed structures and steps will be presented in the following description to explain the technical solutions proposed by the present utility model. The preferred embodiments of the present utility model are described in detail below. However, in addition to these detailed descriptions, the present utility model may also have other embodiments.

[0122] An embodiment of the present utility model provides an electronic device, such as Figure 1 , Figure 2 , Figure 3 and Figure 13 shown. Generally, the electronic device includes a touch device 1 and a touch screen 2. The touch device 1 is electrically connected to the structure in the touch screen 2 through a connection line to control the operation of the touch screen 2. The touch screen 2 can provide an interactive touch and press interface with the user's finger and an electromagnetic pen. In the press interface, the touch screen 2 can sense the press operation of the user or the electromagnetic pen to execute corresponding press feedback or instruct the electronic device where it is located to execute corresponding functions, and this press interface can act as a "button" function. In the touch interface, the touch screen 2 can be used to sense the position and movement of the user's finger to execute corresponding touch feedback or instruct the electronic device where it is located to execute corresponding functions, and this touch interface can act as a "mouse" function. The touch screen 2 can be applied to any type of human-computer interaction device, such as a laptop computer, a tablet computer, a mobile phone, a smart wearable device, a smart door lock, an automated teller machine (ATM), etc. The embodiments of the present disclosure do not limit this.

[0123] The following will specifically describe the touch device 1, especially the touch chip 11, in combination with the touch device 1 and the touch screen 2 in Embodiments 1 - 4:

[0124] Embodiment 1

[0125] An embodiment of the present utility model provides a touch chip 11. The touch chip 11 is an important component of the touch device 1 and is used to connect to the touch screen 2 and control the operation of the touch screen 2. As Figure 1As shown in the figure, the touch screen 2 includes a common voltage line 21 and at least two touch units 22; each touch unit 22 includes a touch electrode 222, a function switching switch 221, and a control circuit 223; the first end of each touch electrode 222 is connected to the common voltage line 21 through a function switching switch 221; each control circuit 223 is connected to the control end of the function switching switch 221 and the connection node between the function switching switch 221 and the touch electrode 222;

[0126] The touch chip 11 includes a common voltage terminal P1, a coding signal terminal P2, and a control signal terminal P3; the common voltage terminal P1 is connected to the common voltage line 21; the coding signal terminal P2 is connected to the second ends of at least two touch electrodes 222; the control signal terminal P3 is connected to the control circuit 223, and the control signal terminal P3 is used to output a control signal to the control circuit 223 to enable the control circuit 223 to control the function switching switch 221 to be turned on or off.

[0127] Among them, the common voltage terminal P1 is a port for providing a common voltage to multiple touch electrodes 222, and the common voltage here can be a GND voltage or other voltages close to the GND voltage. As an example, the common voltage terminal P1 of the touch chip 11 is connected to the common voltage line 21 of the touch screen 2 through an external state switch 12. When the state switch 12 is turned on, the touch chip 11 can provide a common voltage to the touch electrodes 222 connected to the common voltage line 21; when the state switch 12 is turned off, the common voltage line 21 is in a floating state. Or, the common voltage terminal P1 of the touch chip 11 is connected to the common voltage line 21 of the touch chip 2, and an internal switch for connecting the common voltage terminal P1 to other circuits is provided inside the touch chip 11. When the internal switch is turned on, the touch chip 11 can output a common voltage to the common voltage line 21l through the common voltage terminal P1; when the internal switch is turned off, the common voltage terminal P1 is in a floating state, that is, the common voltage line 211 is in a floating state.

[0128] Among them, the coding signal terminal P2 is a port for providing a coding signal to the touch electrodes 222. As an example, the coding signal terminal P2 of the touch chip 11 can be connected to the touch electrodes 222 of the touch screen 2 through a coding circuit 13. Here, the coding circuit 13 can be one or more. Each coding circuit 13 can select a positive and negative coding method for coding, and each coding circuit 13 can perform multi-channel output, that is, it can output a coding signal to multiple touch electrodes 222. Or, a circuit module for outputting a coding signal can also be integrated in the touch chip 11 to enable it to output a coding signal to multiple touch electrodes 222.

[0129] Among them, the control signal terminal P3 is a port for providing a control signal to the control circuit 223.

[0130] In this example, the touch screen 2 connected to the touch chip 11 includes a common voltage line 21 and at least two touch units 22; each touch unit 22 includes a touch electrode 222, a function switching switch 221, and a control circuit 223; the first end of each touch electrode 222 is connected to the common voltage line 21 through a function switching switch 221, the second end of each touch electrode 222 is connected to the coding signal terminal P2 of the touch chip 11, and one end of the common voltage line 21 is connected to the common voltage terminal P1 of the touch chip 11; each control circuit 223 is connected to the control signal terminal P3 of the touch chip 11, the control end of the function switching switch 221, and the connection node between the function switching switch 221 and the touch electrode 222. Among them, the function switching switch 221 is a switch provided between the touch electrode 222 and the common voltage line 21, and is used to switch between the TSP function mode and the EMR function mode. When the function switching switch 221 is closed, the connection between the touch electrodes 222 of different channels and the common voltage line 21 is disconnected, so that a one-way channel is formed between the touch chip 11 and each touch electrode 222, and the touch screen 2 can be controlled to enter the TSP function mode; when the function switching switch 221 is open, the touch electrodes 222 of different channels are connected to the common voltage line 21 together, so that the coding signal terminal P2 of the touch chip 11 and at least two touch electrodes 222 on the same common voltage line 21 form a loop channel, so that the touch chip 11 can control the touch screen 2 to enter the EMR function mode.

[0131] As an example, the common voltage terminal P1 of the touch chip 11 is connected to the common voltage line 21 through a status switch 12, the common voltage line 21 is connected through at least two function switching switches 221, and the first end of each function switching switch 221 is connected to a touch electrode 222. When the status switch 12 is turned on, the touch chip 11 can output a common voltage (such as a GND voltage) to at least two function switching switches 221 corresponding to the same common voltage line 21, or when the status switch 12 is turned off, the common voltage line 21 connected to the common voltage terminal P1 is made to be in a floating state, so that the function switching switch 221 is disconnected from the touch chip 11.

[0132] As an example, the coding signal terminal P2 of the touch chip 11 is connected to the second terminal of the touch chip 11, and can output a coding signal to the touch electrode 222 to enable the touch electrode 222 to perform a coding operation. The coding signal here can be the first coding signal for controlling the touch screen 2 to enter the TSP function mode, or the second coding signal for controlling the touch screen 2 to enter the EMR function mode. In this example, when a circuit for implementing the coding function is built in the touch chip 11, the touch chip 11 can be directly connected to the touch electrode 222 to output a coding signal for controlling the touch electrode 222 to perform a coding operation, so that the touch electrode 222 performs a coding operation; or, when no circuit for implementing the coding function is provided in the touch chip 11, the touch chip 11 can pass through Figures 1 - 3 the coding circuit 13 shown in the figure is connected to the touch electrode 222, so that the touch chip 11 can control the coding circuit 13 to output a coding signal to the touch electrode 222, so that the touch electrode 222 performs a coding operation.

[0133] As an example, the control signal terminal P3 of the touch chip 11 is connected to the control terminal of the function switching switch 221 through the control circuit 223. The control circuit 223 is also connected to the connection node between the function switching switch 221 and the touch electrode 222. The touch chip 11 can output a control signal to the control circuit 223, so that the control circuit 223 can control the function switching switch 221 to open or close based on the control signal. When the function switching switch 221 is closed, a first coding signal can be output to the touch electrode 222 to enable the touch screen 2 to enter the TSP function mode; when the function switching switch 221 is open, a second coding signal can be output to the touch electrode 222 to enable the touch screen 2f to enter the EMR function mode.

[0134] In this example, the control signal terminal P3 of the touch chip 11 controls the function switching switch 221 to open or close through the control circuit 223. Since the control circuit 223 is not only connected to the control terminal of the function switching switch 221, but also connected to the connection node between the function switching switch 221 and the touch electrode 222, when the touch electrode 222 performs a coding process based on the coding signal of the touch chip 11, the coding potential change of the touch electrode 222 can be determined, and the potential of its control terminal can be adjusted based on the coding potential change to ensure the realization of the TSP function mode and the EMR function mode.

[0135] Embodiment 2

[0136] In one embodiment, as Figure 2As shown, each of the control circuits 223 includes a first capacitor C1 and a switch circuit 2231; one end of the first capacitor C1 is connected to the control end of the function switching switch 221, and the other end of the first capacitor C1 is connected to the connection node between the function switching switch 221 and the touch electrode 222; the second end of the switch circuit 2231 is connected to the control end of the function switching switch 221;

[0137] The control signal terminal P3 includes a reference voltage terminal VREF and a switch signal terminal SW. The reference voltage terminal VREF is connected to the first end of the switch circuit 2231, and the switch signal terminal SW is connected to the third end of the switch circuit 2231;

[0138] The switch signal terminal SW outputs a control signal to the switch circuit 2231 to turn the switch circuit 2231 on or off, and the reference voltage terminal VREF outputs a reference voltage to the switch circuit 2231. Based on the reference voltage, the function switching switch 221 is controlled to be turned on or off.

[0139] In this example, each control circuit 223 in the touch screen 2 includes a first capacitor C1 and a switch circuit 2231. The first capacitor C1 is a capacitor used to cooperate with the function switching switch 221 to form a bootstrap circuit. One end of the first capacitor C1 is connected to the control end of the function switching switch 221, and the other end of the first capacitor C1 is connected to the connection node between the function switching switch 221 and the touch electrode 222. When the function switching switch 221 is a TFT, the first capacitor C1 is disposed between the gate and the source of the function switching switch 221. The first end of the switch circuit 2231 is connected to the reference voltage terminal VREF of the touch chip 11, the second end of the switch circuit 2231 is connected to the control end of the function switching switch 221, and the third end of the switch circuit 2231 is connected to the switch signal terminal SW of the touch chip 11.

[0140] As an example, the reference voltage terminal VREF of the touch control chip 11 is connected to the first terminal of the switch circuit 2231, and can output a reference voltage to the first terminal of the switch circuit 2231; the second terminal of the switch circuit 2231 is connected to the control terminal of the function switching switch 221; the switch signal terminal SW of the touch control chip 11 is connected to the third terminal of the switch circuit 2231, and can output a control signal to the third terminal of the switch circuit 2231 to control the opening or closing of the switch circuit 2231, so as to determine whether to transmit the reference voltage output by the touch control chip 11 to the control terminal of the function switching switch 221, so as to control the opening or closing of the function switching switch 221 based on the reference voltage. In this example, when the voltage Vgs between the gate and the source of the function switching switch 221 is less than the conduction threshold |Vthp| under the reference voltage output by the touch control chip 11, the function switching switch 221 is turned off; on the contrary, when the voltage Vgs between the gate and the source of the function switching switch 221 is not less than the conduction threshold |Vthp| under the reference voltage output by the touch control chip 11, the function switching switch 221 is turned off. Among them, the conduction threshold |Vthp| is the threshold for controlling the conduction of the function switching switch 221, and its specific value is determined according to the actual screen factory process. For example, the conduction threshold |Vthp| can be set to 2.7V or other values. It can be understood that since the reference voltage output by the touch control chip 11 needs to control the opening or closing of the function switching switch 221, it is related to the function switching switch 221. For example, when the function switching switch 221 is a TFT, the voltage value range in the conduction state is from -5V to 5V. When it is necessary to enter the TSP function mode, in order to keep it closed, its reference voltage can be set to be consistent with the coding waveform of the touch electrode 222, both of which are close to the GND voltage; when it is necessary to enter the EMR function mode, in order to make it open, it can be set to -2V.

[0141] In this example, since one end of the first capacitor C1 is connected to the control terminal of the function switching switch 221, and the other end of the first capacitor C1 is connected to the connection node between the function switching switch 221 and the touch electrode 222, the first capacitor C1 and the function switching switch 221 cooperate to form a bootstrap circuit. When the touch electrode 222 performs coding based on the coding signal of the touch chip 11, the potential of the control terminal of the function switching switch 221 changes following the coding potential of the touch electrode 222, so as to ensure the realization of the TSP function mode and the EMR function mode. For example, when the touch chip 11 controls the touch screen 2 to enter the TSP function mode, it can control the function switching switch 221 to turn off, enabling it to enter the coding stage of the TSP function mode, so that the touch electrode 222 can perform coding based on the coding signal of the touch chip 11. At this time, the control circuit 223 and the function switching switch 221 cooperate to control the gate voltage of the function switching switch 221 to change following the coding potential of the touch electrode 222, thereby making the off-state current of the function switching switch 221 smaller and avoiding the leakage current of the function switching switch 221 from affecting the TSP function mode of the touch screen 2.

[0142] As a function switching switch for distinguishing between the TSP function mode and the EMR function mode, the magnitude of its own on-resistance will seriously affect the total resistance between the EMR channels. Therefore, it is necessary to consider using a function switching switch with a larger size to reduce the on-resistance Rdson. However, when the size of the function switching switch is large, its corresponding off-state current is large. When it enters the TSP function mode, the signals of adjacent channels will introduce leakage current and affect its normal operation, and there is even a risk of failure of the TSP function mode. Therefore, how to reduce the off-state current of the function switching switch has become an urgent problem to be solved.

[0143] In one embodiment, as Figure 2 shown, the common voltage terminal P1 is connected to the common voltage line 21 through the state switch 12;

[0144] The reference voltage includes a first reference voltage for controlling the function switching switch 221 to turn off;

[0145] The switch signal terminal SW is used to output a first control signal to the switch circuit 2231 to turn on the switch circuit 2231, and the reference voltage terminal VREF is used to output the first reference voltage to the switch circuit 2231 to control the function switching switch 221 to turn off and initialize the potential of the control terminal of the function switching switch 221;

[0146] The switch signal terminal SW is used to output a second control signal to the switch circuit 2231, so as to turn off the switch circuit 2231, keep the function switching switch 221 in the off state, and make the potential of the control terminal of the function switching switch 221 follow the coding potential change of the touch electrode 222;

[0147] When the state switch 12 is in the conducting state, the common voltage terminal P1 is used to output a common voltage to the common voltage line 21, and the coding signal terminal P2 is used to output a first coding signal to the touch electrode 222, so as to make the touch screen 2 enter the TSP function mode.

[0148] The first control signal is a control signal for controlling the switch circuit 2231 to open. The second control signal is a control signal for controlling the switch circuit 2231 to close. The voltage ranges of the first control signal and the second control signal depend on the switch circuit 2231 to be controlled, and can be control signals from -5V to 5V. The control signals can be, but are not limited to, square wave signals or sine wave signals. In this example, either the first control signal or the second control signal is a low-level signal, and the other is a high-level signal. The first control switch TFT1 can be a PTFT, and the PTFT is turned on based on a low-level signal and turned off based on a high-level signal; alternatively, the first control switch TFT1 can also be an NTFT, and the NTFT is conducted based on a high-level signal and cut off based on a low-level signal.

[0149] Among them, the first reference voltage is the reference voltage output by the touch chip 11 for controlling the function switching switch 221 to close, and it is the reference voltage that can initialize the potential of the control terminal of the function switching switch 221. The value range of the first reference voltage depends on the function switching switch 221 to be controlled. When the function switching switch 221 is a PTFT, in order to turn off the PTFT, the first reference voltage can be determined to be 0V. The first coding signal is the coding signal output to the touch electrode 222 when the touch screen 2 enters the TSP function mode. The common voltage is the voltage output by the touch chip 11 to the common voltage line 21 for providing to all function switching switches 221. For example, the common voltage can be the GND voltage or a voltage close to this value. For example, it can be set to 0V.

[0150] The TSP function mode refers to the capacitive touch mode, that is, when the user touches the screen with a finger or other object, the capacitance of the touch point will change, and the touch position is determined by measuring these capacitance changes.

[0151] In one example, when the function switching switch 221 is a TFT (specifically a PTFT), the control process of the touch chip 11 for controlling the touch screen 2 to enter the TSP function mode is as follows:

[0152] (1) The switch signal terminal SW of the touch control chip 11 can output a first control signal to control the switch circuit 2231 to turn on. At the same time, the reference voltage terminal VREF of the touch control chip 11 can output a first reference voltage. When the switch circuit 2231 is turned on, the first reference voltage can be transmitted to the gate of the function switching switch 221 to control the function switching switch 221 to turn off. In this example, when the first reference voltage is transmitted to the gate of the function switching switch 221, the gate potential of the function switching switch 221 can be initialized, that is, an initial gate voltage is provided for the function switching switch 221; at the same time, the corresponding touch electrode 222 also has an initial voltage. At this time, the initial voltage difference between the gate and the source of the function switching switch 221 can be determined. This initial voltage difference can ensure that the voltage Vgs between the gate and the source of the function switching switch 221 is less than the conduction threshold |Vthp|, so that the function switching switch 221 is in the off state, and the voltage Vds between the drain and the source of the function switching switch 221 is also close to 0, making the off-state current of the function switching switch 221 very small. The initial voltage of the touch electrode 222 can be a fixed voltage close to the middle voltage of the coding waveform, for example, it can be the GND voltage. The initial voltage difference is a fixed value determined based on the first reference voltage and the initial voltage of the touch electrode 222.

[0153] (2) The switch signal terminal SW of the touch control chip 11 can output a second control signal to control the switch circuit 2231 to turn off, so that the gate of the function switching switch 221 is in a floating state. By using the bootstrap effect of the capacitor unit formed by the first capacitor C1 and the parasitic capacitor Cgs of the function switching switch 221 itself, the gate potential of the function switching switch 221 is maintained. When the TSP function mode enters the coding stage, the gate potential of the function switching switch 221 can follow the coding potential change, and it is ensured that the voltage Vgs between the gate and the source of the function switching switch 221 is less than the conduction threshold |Vthp|, so that the function switching switch 221 is in the off state, so that the off-state current of the function switching switch 221 is small, so as to avoid the leakage current of the function switching switch 221 from affecting the implementation of the TSP function mode.

[0154] (3) When the function switching switch 221 is in the off state and the state switch 12 is in the conducting state, the common voltage terminal P1 is used to output a common voltage to the common voltage line 21, and the coding signal terminal P2 can output a first coding signal to the touch electrode 222, so that the touch screen 2 enters the TSP function mode. During this process, the voltage Vgs of the function switching switch 221 changes with the coding potential, so that although the voltage Vds of the function switching switch 221 has a certain change, the finally formed off-state current is small, so as to avoid the leakage current of the function switching switch 221 affecting the realization of the TSP function mode. In this example, the common voltage output by the touch chip 11 can be the GND voltage or other voltages close to the GND voltage, so as to keep the touch electrode 222 in the off state and ensure that the off-state current is small.

[0155] In one embodiment, as Figure 2 shown, the reference voltage includes a second reference voltage for controlling the switch circuit 2231 to turn off;

[0156] When the switch signal terminal SW is used to output a second control signal to the switch circuit 2231, the reference voltage terminal VREF outputs the second reference voltage to the switch circuit 2231, so that the switch circuit 2231 maintains the off state.

[0157] Among them, the second reference voltage is the reference voltage output by the touch chip 11 for maintaining the switch circuit 2231 in the off state, and its voltage magnitude depends on the switch circuit 2231 to be controlled. For example, when the switch circuit 2231 is a PTFT, the second reference voltage can be the GND voltage or a voltage close to this value to turn off the PTFT.

[0158] As an example, the switch signal terminal SW of the touch chip 11 outputs a second control signal to the third terminal of the switch circuit 2231. While closing the switch circuit 2231, the reference voltage terminal VREF of the touch chip 11 outputs a second reference voltage to the first terminal of the switch circuit 2231 to adjust the voltage of the first terminal of the switch circuit 2231 to the GND voltage or a fixed voltage close to this value, so as to avoid the output signal of other circuits coupled to the first terminal of the switch circuit 2231 from changing the voltage of the first terminal of the switch circuit 2231, so that the switch circuit 2231 cannot maintain the off state and affect the realization of the TSP function mode.

[0159] In one embodiment, as Figure 2 shown, the coding signal terminal P2 is used to output a first coding signal to at least two of the touch electrodes 222 simultaneously.

[0160] As an example, when the function switching switch 221 is turned off, the touch chip 11 and the multiple touch electrodes 222 form a unidirectional channel. When the function switching switch 221 is in the off state, the coding signal terminal P2 of the touch chip 11 outputs a first coding signal to at least two touch electrodes 222 corresponding to the same common voltage line 21 at the same time, so that the coding current flows through at least two touch electrodes 222 corresponding to the same common voltage line 21 at the same time, so that the touch screen 2 enters the TSP function mode (the timing is as Figure 5 、 Figure 12 、 Figure 14 and Figure 19 shown), to ensure the coding efficiency of the TSP function mode. During the coding process, due to the bootstrap effect of the capacitance unit formed between the first capacitor C1 and the parasitic capacitance Cgs of the function switching switch 221, the gate potential of the function switching switch 221 can be controlled to follow the change of its coding potential, so that the off-state current of the function switching switch 221 is small.

[0161] In an embodiment, as Figure 2 and Figure 3 shown, the common voltage terminal P1 is connected to the common voltage line through the state switch 12;

[0162] The reference voltage includes a third reference voltage for controlling the function switching switch 221 to open;

[0163] The switch signal terminal SW is used to output a first control signal to the switch circuit 2231 to make the switch circuit 2231 open, and the reference voltage terminal VREF is used to output the third reference voltage to the switch circuit 2231 to control the function switching switch 221 to open;

[0164] When the state switch 12 is in the off state, the coding signal terminal P2 is used to output a second coding signal to the touch electrode 222, so that the touch screen 2 enters the EMR function mode.

[0165] Among them, the third reference voltage is the reference voltage output by the touch chip 11 for controlling the function switching switch 221 to open. The value range of the third reference voltage depends on the function switching switch 221 to be controlled. When the function switching switch 221 is a PTFT, in order to make the PTFT open, the third reference voltage can be determined to be -2V. The second coding signal is the coding signal output to the touch electrode 222 when the touch screen 2 enters the EMR function mode. The EMR function mode is an electromagnetic touch mode, that is, when the user operates the electromagnetic pen to touch the screen, the touch screen 2 will sense the corresponding electromagnetic signal to determine the touch position through the magnetic flux.

[0166] In some possible embodiments, when the function switching switch 221 is a TFT (specifically, it can be a PTFT), the switch signal terminal SW of the touch control chip 11 can output a first control signal to control the switch circuit 2231 to turn on. At the same time, the reference voltage terminal VREF of the touch control chip 11 can output a third reference voltage. When the switch circuit 2231 is turned on, the third reference voltage can be transmitted to the gate of the function switching switch 221, so that the voltage between the gate and the source of the function switching switch 221 is greater than or equal to the conduction threshold |Vthp|, and the third reference voltage can control the function switching switch 221 to turn on. When the state switch 12 is in the off state (such as Figure 7 and Figure 18 in the HiZ state), that is, to control the common voltage line 21 to be in a floating state, the coding signal terminal P2 of the touch control chip 11 and at least two touch electrodes 222 on the same common voltage line 21 form a loop channel. At this time, the coding signal terminal P2 of the touch control chip 11 outputs a second coding signal to the touch electrode 222, so that the touch screen 2 enters the EMR function mode. In this example, the state switch 12 is arranged between the common voltage terminal P1 and the common voltage line 21. The state switch 12 can be connected to the touch control chip 11 and is turned on or off based on the control signal output by the touch control chip 11, or can be connected to other control devices and be controlled by other control devices.

[0167] In one embodiment, as shown in Figure 7 , Figure 8 , Figure 15 and Figure 18 , the common voltage line 21 includes a first common voltage line 221 connected to at least three touch electrodes 222;

[0168] The coding signal terminal P2 is used to output a second coding signal to at least three touch electrodes 222 corresponding to the same first common voltage line 21 one by one.

[0169] As an example, the common voltage line 21 connected to the common voltage terminal P1 of the touch chip 11 may be the first common voltage line 211. The first common voltage line 211 is a common voltage line 21 connected to at least three touch electrodes 222. In this example, the common voltage terminal P1 of the touch chip 11 is connected to one end of the first common voltage line 211. The first common voltage line 211 is further connected to at least three function switching switches 221, and each function switching switch 221 is connected to a touch electrode 222. When the state switch 12 is in the off state, that is, the first common voltage line 211 is in the floating state, the first common voltage line 211 and at least three touch electrodes 222 cooperate to form a coil structure similar to a comb structure; the coding signal terminal P2 of the touch chip 11 is further connected to the second ends of at least three touch electrodes 222 corresponding to the same first common voltage line 211; the coding signal terminal P2 of the touch chip 11 can output a second coding signal to at least three touch electrodes 222 corresponding to the same first common voltage line 211 one by one (the timing is as Figure 9 、 Figure 12 、 Figure 16 and Figure 19 shown), so that the coding current flows through at least three touch electrodes 222 in sequence, so as to ensure that only one touch electrode 222 is coded based on the second coding signal at the same time, avoiding signal crosstalk. This method requires fewer common voltage lines 21, which helps to save costs and the occupied area.

[0170] In an embodiment, as Figure 10 and Figure 11 shown, the common voltage line 21 includes a second common voltage line 222 connected to two touch electrodes 222;

[0171] The coding signal terminal P2 is used to simultaneously output a second coding signal to two touch electrodes 222 corresponding to the same second common voltage line 21.

[0172] As an example, the common voltage line 21 connected to the common voltage terminal P1 of the touch chip 11 may be the second common voltage line 212, and the second common voltage line 212 is the common voltage line 21 connected to two touch electrodes 222. In this example, the common voltage terminal P1 of the touch chip 11 is connected to one end of the second common voltage line 212, and the second common voltage line 212 is further connected to two function switching switches 221, and each function switching switch 221 is connected to a touch electrode 222. When the state switch 12 is in the off state, that is, the first common voltage line 211 is in the floating state, a loop channel is formed between the two touch electrodes 222 corresponding to the first common voltage line 211 and the two coding signal terminals P2 of the touch chip 11, so that the touch chip 11 can simultaneously output the second coding signal to the two touch electrodes 222 corresponding to the same second common voltage line 212, and the coding current flows through the two touch electrodes 222 at the same time. This method can effectively shorten the coding time and help improve the coding efficiency.

[0173] Embodiment 3

[0174] In one embodiment, as Figures 3 - 12 shown, the switch circuit 2231 includes a first control switch TFT1, and the second end of the first control switch TFT1 is connected to the control end of the function switching switch 221;

[0175] The reference voltage terminal VREF is connected to the first end of the first control switch TFT1, and the switch signal terminal SW is connected to the control end of the first control switch TFT1;

[0176] The switch signal terminal SW outputs a first control signal to the first control switch TFT1 to turn on the first control switch TFT1, or outputs a second control signal to the first control switch TFT1 to turn off the first control switch TFT1.

[0177] As an example, the switch circuit 2231 includes a first control switch TFT1. The reference voltage terminal VREF is used to connect to the first end of the first control switch TFT1 to output a reference voltage to the first control switch TFT1; the switch signal terminal SW is used to connect to the control end of the first control switch TFT1 to output a control signal to the first control switch TFT1, so as to control the first control switch TFT1 to turn on or off through the control signal output by the switch signal terminal SW and the reference voltage output by the reference voltage terminal VREF.

[0178] In this example, the first control switch TFT1 is arranged between the reference voltage terminal VREF of the touch chip 11 and the control terminal of the function switching switch 221. The control terminal of the first control switch TFT1 is connected to the switch signal terminal SW of the touch chip 11, and can be turned on based on the first control signal output by the touch chip 11 and turned off based on the second control signal output by the touch chip 11. In this example, any one of the first control signal and the second control signal is a low-level signal, and the other is a high-level signal. The first control switch TFT1 can be a PTFT, and the PTFT is turned on based on the low-level signal and turned off based on the high-level signal; alternatively, the first control switch TFT1 can also be an NTFT, and the NTFT is turned on based on the high-level signal and turned off based on the low-level signal.

[0179] As Figure 8 shown, when the first control switch TFT1 and the function switching switch 221 are TFTs, the drain of the first control switch TFT1 is connected to the reference voltage terminal VREF of the touch chip 11 and can receive the reference voltage output by the touch chip 11; the source of the first control switch TFT1 is connected to the gate of the function switching switch 221; the gate of the first control switch TFT1 is connected to the switch signal terminal SW of the touch chip 11 and can be turned on or off according to different level signals output by the switch signal terminal SW of the touch chip 11 to determine whether to transmit the reference voltage output by the touch chip 11 to the gate of the function switching switch 221. In this example, when the switch signal terminal SW of the touch chip 11 outputs the first control signal, the first control switch TFT1 can be controlled to turn on, so that the first reference voltage output by the reference voltage terminal VREF is transmitted to the gate of the function switching switch 221, the function switching switch 221 is controlled to be in the off state, and the gate potential of the function switching switch 221 is initialized; when the switch signal terminal SW of the touch chip 11 outputs the second control signal, the first control switch TFT1 can be controlled to turn off, so that the function switching switch 221 remains in the off state. When the TSP function mode enters the coding stage, the first capacitor C1 and the function switching switch 221 cooperate to form a bootstrap circuit, which can make the gate potential of the function switching switch 221 follow the coding potential change of the touch electrode 222, so that the off-state current of the function switching switch 221 is small, so as to avoid the leakage current of the function switching switch 221 from affecting the implementation of the TSP function mode.

[0180] In this example, the control circuit 223 includes a switching circuit 2231 and a first capacitor C1. The two ends of the first capacitor C1 are respectively connected to the gate and source of the function switching switch 221, so that the first capacitor C1 cooperates with the function switching switch 221 to form a bootstrap circuit that can achieve the bootstrap effect. The first end of the first control switch TFT1 is connected to the reference voltage terminal VREF of the touch chip 11, and can receive the reference voltage VREF output by the touch chip 11; the second end of the first control switch TFT1 is connected to the gate of the function switching switch 221; the switch signal terminal SW of the touch chip 11 is connected to the control end of the first control switch TFT1, and can output different level signals to the control end of the first control switch TFT1 to control the first control switch TFT1 to turn on or off, so as to determine whether the reference voltage VREF provided by the touch chip 11 can be transmitted to the function switching switch 221, and control the function switching switch 221 to turn on or off based on the reference voltage VREF. Since the first capacitor C1 and the function switching switch 221 cooperate to form a bootstrap circuit, the gate potential of the function switching switch 221 can follow the coding potential change of the touch electrode 222, so that the off-state current of the function switching switch 221 is smaller, so as to avoid the leakage current of the function switching switch 221 affecting the realization of the TSP function mode.

[0181] Embodiment 4

[0182] In one embodiment, as Figures 13 - 19 shown, the switching circuit 2231 further includes a voltage boosting circuit 22311, and the voltage boosting circuit 22311 is connected to the connection node between the second end of the first control switch TFT1 and the control end of the function switching switch 221;

[0183] The control signal terminal P3 is further used to be connected to the voltage boosting circuit 22311 to output a control signal in a second voltage range to the voltage boosting circuit 22311, so that the voltage boosting circuit 22311 boosts the control signal in the second voltage range and converts it into a control signal in a first voltage range to control the function switching switch 222 to turn on or off.

[0184] Among them, the second voltage range is a voltage range that cannot directly control the control switch in the function switching switch 222 to turn on or off based on the performance of the touch chip 11 itself. The first voltage range is a voltage range that can directly control the control switch in the function switching switch 222 to turn on or off based on the performance of the touch chip 11 itself.

[0185] As an example, when the function switching switch 222 is a TFT, the first voltage range for controlling the opening or closing of the TFT is a relatively high voltage range (such as 3V - 8V). If the touch chip 11 is a touch chip 11 prepared based on a low-voltage manufacturing process, the touch chip 11 outputs a control signal in a second voltage range. At this time, a voltage boosting circuit 22311 needs to be set on the touch screen 2. The voltage boosting circuit 22311 is set between the control signal terminal P3 of the touch chip 11 and the control terminal of the function switching switch 221, and can boost the control signal in the second voltage range output from the common voltage terminal P1 into a control signal in the first voltage range, so as to open or close the function switching switch 222. In this example, since the voltage boosting circuit 22311 is set on the touch screen 2 to boost the signal, the voltage range output by the touch chip 11 can be appropriately reduced. A touch chip 11 manufactured by a conventional low-voltage manufacturing process can be used to control the touch screen 2, instead of selecting a touch chip 11 manufactured by a particularly high-voltage manufacturing process, which helps to reduce the cost of the touch chip 11.

[0186] In one embodiment, as Figure 13 shown, the voltage boosting circuit 22311 includes a second control switch TFT2, a third control switch TFT3, a fourth control switch TFT4, a fifth control switch TFT5, and a second capacitor C2; the second control switch TFT2, the third control switch TFT3, and the fourth control switch TFT4 are connected in series in sequence, and the fourth control switch TFT4 is connected to the control terminal of the function switching switch 221; the second terminal of the fifth control switch TFT5 is connected to the connection node between the third control switch TFT3 and the fourth control switch TFT4, and the control terminal of the fifth control switch TFT5 is connected to the control terminal of the fourth control switch TFT4; both ends of the second capacitor C2 are respectively connected to the second terminal of the fifth control switch TFT5 and the control terminal of the fifth control switch TFT5;

[0187] The switch signal terminal SW includes a first switch signal terminal SW1 and a second switch signal terminal SW2; the control signal terminal P3 further includes an input terminal IN, a negative power supply terminal VEE, and a clock signal terminal CLK;

[0188] The first switch signal terminal SW1 is used to connect to the control terminal of the first control switch TFT1 and output a first switch signal to the first control switch TFT1; the second switch signal terminal SW2 is used to connect to the control terminal of the second control switch TFT2 and output a second switch signal to the second control switch TFT2; the input terminal IN is used to connect to the first terminal of the second control switch TFT2 and output a first voltage to the second control switch TFT2; the negative power supply terminal VEE is used to connect to the control terminal of the third control switch TFT3 and output a VEE voltage to the third control switch TFT3; the clock signal terminal CLK is used to connect to the first terminal of the fifth control switch TFT5 and output a second voltage to the fifth control switch TFT5; based on the first switch signal, the second switch signal, the first voltage, the VEE voltage and the second voltage, control the voltage boosting circuit 22311 to boost the voltage.

[0189] Among them, the first switch signal is a switch signal used to control the operation of the first control switch TFT1, which can be a high-level signal or a low-level signal. The second switch signal is a switch signal used to control the operation of the second control switch TFT2, which can be a high-level signal or a low-level signal. The first voltage is the voltage output from the input terminal IN to the second control switch TFT2, and can be adjusted independently according to the actual situation. For example, it can be a VDD voltage or a VEE voltage. The negative power supply terminal VEE outputs a VEE voltage to the third control switch TFT3, so that the third control switch TFT3 is in an open state and is only used as a limiting tube for reverse leakage current limitation. The second voltage is the voltage output from the clock signal terminal CLK to the fifth control switch TFT5, and can be adjusted independently according to the actual situation. For example, it can be a GND voltage or a VEE voltage. Here, the VDD voltage is the positive power supply voltage, that is, the operating voltage of the touch chip 11, and its value range can be set to +3.3V to 5V; the VEE voltage is the negative power supply voltage, and its value can be set to -5V, -8V or other negative power supply voltages; the GND voltage is the voltage of the zero potential reference point, and its value is 0V.

[0190] As an example, the switch signal terminal SW includes a first switch signal terminal SW1 and a second switch signal terminal SW2. The first switch signal terminal SW1 is used to connect to the control terminal of the first control switch TFT1; the control signal terminal P3 further includes an input terminal IN, a negative power supply terminal VEE, and a clock signal terminal CLK; the first switch signal terminal SW1 of the touch control chip 11 is connected to the first control switch TFT1, and the voltage boosting circuit 22311 includes a second control switch TFT2, a third control switch TFT3, a fourth control switch TFT4, a fifth control switch TFT5, and a second capacitor C2; the second control switch TFT2, the third control switch TFT3, and the fourth control switch TFT4 are connected in series in sequence, and the fourth control switch TFT4 is connected to the control terminal of the function switching switch PTFT1; the second terminal of the fifth control switch TFT5 is connected to the connection node between the third control switch TFT3 and the fourth control switch TFT4; when the two ends of the second capacitor C2 are respectively connected to the second terminal of the fifth control switch TFT5 and the control terminal of the fifth control switch TFT5, the input terminal IN is used to connect to the first terminal of the second control switch TFT2, and the second switch signal terminal SW2 is used to connect to the control terminal of the second control switch TFT2; the negative power supply terminal VEE is used to connect to the control terminal of the third control switch TFT3; the clock signal terminal CLK is used to connect to the first terminal of the fifth control switch TFT5. In this example, the first control switch TFT1 can be controlled to be turned on or off according to the first switch signal output by the first switch signal terminal SW1, and the second control switch TFT2 can be controlled to be turned on or off according to the second switch signal output by the second switch signal terminal SW2. Then, in combination with the reference voltage output by the reference voltage terminal VREF to the first control switch TFT1, the first voltage output by the input terminal IN to the second control switch TFT2, the VEE voltage output by the negative power supply terminal VEE to the third control switch TFT3, and the second voltage output by the clock signal terminal CLK to the fifth control switch TFT4, the voltage differences at both ends of each control switch are compared to control the third control switch TFT3, the fourth control switch TFT4, and the fifth control switch TFT5 to be turned on or off, so that while switching between the TSP function mode and the EMR function mode, the purpose of voltage boosting can be achieved.

[0191] In one embodiment, the first switch signal terminal SW1 is used to output a first control signal to the first control switch TFT1 to turn on the first control switch TFT1, and the reference voltage terminal VREF is used to output a first reference voltage to the first control switch TFT1 to turn off the function switching switch 221;

[0192] The second switch signal terminal SW2 is used to output a first control signal to the second control switch TFT2 to turn on the second control switch TFT2. The input terminal IN is used to output a VDD voltage to the second control switch TFT2. The clock signal terminal CLK is used to output a GND voltage to the fourth control switch TFT4 to turn off the fourth control switch TFT4 and the fifth control switch TFT5.

[0193] As an example, as Figure 14 and Figure 15 shown, the touch chip 11 sequentially performs the following operations to control the touch screen 2 to enter the TSP function mode:

[0194] The first switch signal terminal SW1 outputs a first control signal to the first control switch TFT1 to turn on the first control switch TFT1, and the reference voltage terminal VREF outputs a reference voltage to the first control switch TFT1 to transmit the reference voltage output by the reference voltage terminal VREF to the gate node (i.e., the N1 node) of the function switching switch PTFT1, so that the gate potential of the function switching switch PTFT1 is adjusted from the initial GND voltage to the reference voltage.

[0195] The second switch signal terminal SW2 outputs a first control signal to the second control switch TFT2 to turn on the second control switch TFT2 based on the first control signal to transmit the VDD voltage output by the input terminal IN to the N3 node. The negative power supply terminal VEE outputs a VEE voltage to the third control switch TFT3 to keep the third control switch TFT3 in a normally open state. At this time, the VDD voltage output by the input terminal IN can be transmitted to the N2 node. When the VDD voltage is greater than the reference voltage, the potential of the N2 node is higher than that of the N1 node, so that the fourth control switch TFT4 is in the off state throughout the TSP working interval, and the gate potential of the function switching switch PTFT can be initialized based on the reference voltage. At the same time, during this period, the N1 node is at a high potential, the second control switch TFT2 is turned off based on the second control signal output by the second switch signal terminal SW2, the N2 node is at a high potential, and the clock signal terminal CLK is used to output a GND voltage to the fourth control switch TFT4 to turn off the fifth control switch TFT5, ensuring that the off-state current of the fifth control switch TFT5 is also as small as possible to reduce the static current consumption of the entire system.

[0196] In this example, when it is necessary to control the touch screen 2 to enter the TSP function mode, first control the first control switch TFT1 to turn on based on the first control signal output from the first switch signal terminal SW1, so as to transmit the reference voltage output from the reference voltage terminal VREF to the N1 node, and complete the initialization of the gate potential of the function switching switch PTFT1. After other circuits in the circuit are initialized, they remain in the off state. The process of the coding stage in the TSP function mode is the same as that of the coding stage in the TSP function mode in the above embodiment. To avoid repetition, it will not be elaborated here one by one.

[0197] In one embodiment, the first switch signal terminal SW1 is used to output a first control signal to the first control switch TFT1 to turn on the first control switch TFT1, and the reference voltage terminal VREF is used to output a VEE voltage to the first control switch TFT1 to turn on the function switching switch 221;

[0198] The second switch signal terminal SW2 is used to output a first control signal to the second control switch TFT2 to turn on the second control switch TFT2. The input terminal IN outputs a VEE voltage to the second control switch TFT2. The clock signal terminal CLK outputs a GND voltage to the fifth control switch TFT5 to turn off the fourth control switch TFT4 and turn on the fifth control switch TFT5;

[0199] The first switch signal terminal SW1 is used to output a second control signal to the first control switch TFT1 to turn off the first control switch TFT1. The second switch signal terminal SW2 is used to output a second control signal to the second control switch TFT2 to turn off the second control switch TFT2. The clock signal terminal CLK outputs a VEE voltage to the fifth control switch TFT5 to turn on the fourth control switch TFT4 and the fifth control switch TFT5.

[0200] As an example, as Figures 16 to 19 shown, the touch chip 11 sequentially performs operations in the following three states to control the touch screen 2 to enter the EMR function mode:

[0201] State 1: The first switch signal terminal SW1 is used to output a first control signal to the first control switch TFT1 to turn on the first control switch TFT1, and the reference voltage terminal VREF is used to output the VEE voltage to the first control switch TFT1 to turn on the function switching switch 221. For example, when the first control switch TFT1 is a unipolar PTFT, the unipolar PTFT will lose a |Vthp| when it is turned on at the lowest potential. Therefore, based on the reference voltage output from the reference voltage terminal VREF, the first control switch TFT1 pulls down the potential of the first terminal of the first control switch TFT1 to the low level VEE, and the first control switch TFT1 is turned on based on the first control signal output from the first switch signal terminal SW1, so that the N1 node maintains VEE + |Vthp|.

[0202] State 2: The second switch signal terminal SW2 is used to output a first control signal to the second control switch TFT2 to turn on the second control switch TFT2; the input terminal IN outputs the VEE voltage to the second control switch TFT2, so that the low level VEE received by the first terminal of the second control switch TFT2 is adjusted by the third control switch TFT3 to adjust the potential of the N2 node to VEE + 2x|Vthp|. In this case, the fourth control switch TFT4 is a tube connected in the diodeConnect manner, and its Vsg < |Vthp|, so that the fourth control switch TFT4 will not be turned on, and thus the potential of the N1 node and the potential of the N2 node are each maintained. At the same time, the first terminal of the fifth control switch TFF5 receives the GND voltage output from the clock signal terminal CLK of the touch control chip 11, and the potential of the N2 node will control the fifth control switch TFT5 to turn on.

[0203] State 3: The first switch signal terminal SW1 is used to output a second control signal to the first control switch TFT1 to turn off the first control switch TFT1, and the second switch signal terminal SW2 is used to output a second control signal to the second control switch TFT2, that is, the control signals of the first switch signal terminal SW1 and the second switch signal terminal SW2 are pulled high to turn off the first control switch TFT1 and the second control switch TFT2. The first end of the fifth control switch TFF5 is based on the VEE voltage output by the clock signal terminal CLK, so that the first end of the fifth control switch TFF5 changes from the GND level to the VEE level. Since the fifth control switch TFT5 and the second capacitor C2 form a bootstrap structure, the potential of the N4 node will be pulled to the VEE potential, and the N2 node will also change from VEE + 2x|Vthp| to 2xVEE + 2x|Vthp|. At this time, since the Vsg of the fourth control switch TFT4 satisfies Vsg > |Vthp|, the potential of the N1 node is adjusted to 2xVEE + 3x|Vthp|. Based on this, the potential of the N1 node can be made less than the value of the VEE voltage through the above structure, which can meet the requirements of a larger driving voltage range.

[0204] The manufacturing processes used by the conventional touch chip 11 are all based on the VDD-VEE range, generally the low-voltage manufacturing process from +5V to -5V, while the voltage range of the high and low levels of the conventional PTFT is from +8V to -8V. Therefore, through the above first-level bootstrap circuit, the control level of the N1 node can be adjusted below the VEE level to better control the on-resistance Rdson of the PTFT1. Since the Vds of the PTFT1 is fixed, the lower the Vg, the smaller its Rdson. In this example, since the subsequent TX1 uses a sine wave signal in the EMR coding stage, a small part of the fluctuation is also coupled to the N1 node through the first capacitor C1, and a part of the jitter is also filtered through the fourth control switch TFT4, making the disturbance of the N2 node smaller. As Figure 19 shown, after the touch chip 11 controls the touch screen 2 to complete a TSP function mode and / or an EMR function mode, it is necessary to control the touch screen 2 to complete an initialization operation, that is, to initialize the potential (i.e., the gate potential) of the control end of the function switching switch 221 through the reference voltage output by the reference voltage terminal VERF to ensure the accuracy of the control process and avoid the cumulative error of multiple operations affecting the control accuracy.

[0205] In this example, when it is necessary to control the touch screen 2 to enter the EMR function mode, first, the potentials of both the N1 node and the N2 node are set low. Then, by changing the potential of the clock signal terminal CLK from the GND voltage to the VEE voltage, the bootstrap architecture formed by the fifth control switch TFT5 and the second capacitor C2 pulls the potential of the N2 node to a lower level, and transmits a lower level to the N1 node through the fourth control switch transistor TFT4, so as to complete the purpose of adjusting the N1 node to a level lower than VEE, thus achieving the purpose of controlling a larger driving voltage range by using a standard TP-IC process.

[0206] In one embodiment, the touch chip is configured to output a control signal within a first voltage range to the control circuit 223, so that the control circuit 223 controls the function switching switch 222 to be turned on or off.

[0207] Wherein, the first voltage range is a voltage range that can directly control the control switch in the function switching switch 222 to be turned on or off based on the performance of the touch chip 11 itself.

[0208] For example, when the function switching switch 222 is a TFT, its corresponding first voltage range is a relatively high voltage range (such as 3V - 8V). If the touch chip 11 is a touch chip 11 prepared based on a high-voltage manufacturing process, the touch chip 11 can directly output a control signal within the first voltage range to the control circuit 223, so that the control circuit 223 controls the function switching switch 222 to be turned on or off.

[0209] An embodiment of the present invention provides a touch device 1, such as Figure 2 and Figure 3 shown, including the touch chip 11 and the status switch 12 in the above embodiment;

[0210] One end of the status switch is connected to the common voltage terminal of the touch chip, and the other end of the status switch is used to connect to the common voltage line of the touch screen.

[0211] As an example, the touch device 1 includes a touch chip 11 and a status switch 12. The status switch 12 is disposed between the common voltage terminal P1 of the touch chip 11 and the common voltage line 21 of the touch screen 2. The control end of the status switch 12 can be connected to the touch chip 11 or other control devices. When it is necessary to control the touch screen 2 to enter the TSP function mode, the status switch 12 is controlled to conduct, and the touch chip 11 can output a common voltage to the common voltage line 21 through the common voltage terminal P1, so that the function switching switch 211 remains in the off state; conversely, when it is necessary to control the touch screen 2 to enter the EMR function mode, the status switch 12 is controlled to disconnect, so that the common voltage line 21 is in a floating state, and the touch screen 2 enters the EMR function mode.

[0212] In one embodiment, as Figures 1 - 3 shown, the touch device 1 further includes a coding circuit 13;

[0213] One end of the coding circuit 13 is connected to the coding signal terminal P2 of the touch chip 11, and the other end of the coding circuit 13 is used to connect to the touch electrode 222 of the touch screen 2.

[0214] As an example, one end of the coding circuit 13 is connected to the coding signal terminal P2 of the touch chip 11, and the other end of the coding circuit 13 is used to connect to the touch electrode 222 of the touch screen 2, so as to output a coding current to the touch electrode 222 according to the coding signal output by the coding signal terminal P2 of the touch chip 11, so that the touch screen 2 can enter the TSP function mode or the EMR function mode. Here, the coding circuit 13 can be one or more. Each coding circuit 13 can select positive and negative coding methods for coding, and each coding circuit 13 can perform multi-channel output, that is, it can control multiple touch electrodes 222 for coding. The control signal terminal P3 is a port for providing a control signal to the control circuit 223.

[0215] In some possible implementation manners, the coding signal output by the coding signal terminal P2 can be a sine wave signal or a square wave signal, which can be determined independently according to the actual situation. Here, the coding signal can be a first coding signal for entering the TSP function mode or a second coding signal for entering the EMR function mode. In this example, the first coding signal and the second coding signal are preferably sine wave signals, and the sine wave signal can make the current smoother and better ensure the realization of its function.

[0216] In one embodiment, as Figure 3 shown, the touch device 1 further includes a power rail 13. One end of the power rail 13 is connected to the control signal terminal P3 of the touch chip 11, and the other end of the power rail 13 is used to connect to the control circuit 223 of the touch screen 2;

[0217] The touch chip 11 is used for control signals in a second voltage range;

[0218] The power rail 13 is used to convert the control signal in the second voltage range and output a control signal in a first voltage range to the control circuit 223, so that the control circuit 223 controls the function switching switch 222 to be turned on or off.

[0219] As an example, when the function switching switch 222 is a TFT, its corresponding first voltage range is a relatively high voltage range (such as 3V - 8V). If the touch chip 11 of the touch chip 11 is fabricated based on a low-voltage manufacturing process, the touch chip 11 outputs a control signal in a second voltage range, and the second voltage range is a relatively low voltage range (such as 0V - 5V). Therefore, one or more power rails 13 need to be provided between the touch chip 11 and the switch signal terminal SW to convert the control signal in the second voltage range into a control signal in the first voltage range, and the function switching switch 222 is turned on or off. The power rail 13 here can be a structure for voltage conversion constructed based on Deep N-WELL isolation (i.e., DNW isolation) technology and can be provided on the touch chip 11. This isolation technology isolates an independent area, namely a deep N-well (DNW), on the P-sub to achieve the isolation effect on internal devices. The main purpose of isolation from the outside is to weaken the mutual influence, especially the isolation in potential, such as in the case of dealing with multiple ground potentials (0V, -3.3V, -6V, etc.).

[0220] The following will describe the touch screen 2 in detail with reference to the touch device 1 and the touch screen 2 in Embodiments 1 - 4:

[0221] Embodiment 1

[0222] An embodiment of the present utility model provides a touch screen 2, as Figure 1 shown, the touch screen 2 is used to connect to the touch chip 11, and the touch screen 2 includes a common voltage line 21 and at least two touch units 22;

[0223] Each of the touch units 22 includes a touch electrode 222, a function switching switch 221, and a control circuit 223;

[0224] The first end of each touch electrode 222 is connected to the common voltage line 21 through a function switching switch 221, and the second end of each touch electrode 222 is used to connect to the coding signal terminal P2 of the touch chip 11; the common voltage line 21 is used to connect to the common voltage terminal P1 of the touch chip 11;

[0225] Each control circuit 223 is connected to the control end of the function switching switch 221 and the connection node between the function switching switch 221 and the touch electrode 222, and is also used to connect to the control signal terminal P3 of the touch chip 11, and is used to control the function switching switch 221 to be turned on or off according to the control signal output from the control signal terminal P3.

[0226] Among them, the function switching switch 221 is arranged between the touch electrode 222 and the common voltage line 21, and is a switch for switching between the TSP function mode and the EMR function mode. When the function switching switch 221 is turned off, the connection between the touch electrodes 222 of different channels and the common voltage line 21 is disconnected, so that a one-way channel is formed between the touch chip 11 and each touch electrode 222, and the touch screen 2 can be controlled to enter the TSP function mode; when the function switching switch 221 is turned on, the touch electrodes 222 of different channels are connected to the common voltage line 21 together, so that the coding signal terminal P2 of the touch chip 11 and at least two touch electrodes 222 on the same common voltage line 21 form a loop channel, so that the touch chip 11 can control the touch screen 2 to enter the EMR function mode. In this example, the touch electrode 222 can be a driving electrode TX or a sensing electrode RX.

[0227] As an example, the touch screen 2 is provided with a common voltage line 21 and at least two touch units 22. The touch unit 22 includes, but is not limited to, a touch electrode 222, a function switching switch 221, and a control circuit 223. Each function switching switch 221 is arranged between the touch electrode 222 and the common voltage line 21, that is, the common voltage line 21 is connected to the first ends of at least two function switching switches 221, and the second end of each function switching switch 221 is connected to a touch electrode 222. For example, the common voltage line 21 is connected to the common voltage terminal P1 of the touch chip 11 through the state switch 12. When the state switch 12 is turned on, the common voltage line 21 can receive the common voltage (such as GND voltage or a voltage close to this value) output by the touch chip 11. When the state switch 12 is turned off, the common voltage line 21 is in a floating state. The control circuit 223 is connected to the control signal terminal P3 of the touch chip 11 and the control end of the function switching switch 221, can receive the control signal sent by the touch chip 11, and based on the control signal, control the function switching switch 221 to turn off and adjust the potential of the control end of the function switching switch 221, so that the potential of the control end of the function switching switch 221 changes following the coding potential of the touch electrode 222, so as to ensure the realization of the TSP function mode and the EMR function mode.

[0228] When the function switching switch 221 is a thin film transistor (TFT), the drain of the function switching switch 221 is connected to the common voltage line 21, the source of the function switching switch 221 is connected to the touch electrode 222, and the gate (i.e., the control terminal) of the function switching switch 221 is connected to the control circuit 223. The control circuit 223 can control the function switching switch 221 to turn off according to the control signal output by the touch chip 11, so that the touch screen 2 enters the TSP function mode, and the touch electrode 222 can receive the first coding signal output by the touch chip 11. At this time, the control circuit 223 and the function switching switch 221 cooperate to control the gate voltage of the function switching switch 221 to follow the coding potential change of the touch electrode 222, so that the off-state current of the function switching switch 221 is small, and the leakage current of the function switching switch 221 is prevented from affecting the TSP function mode of the touch screen 2. In this example, the function switching switch 221 can be a PTFT, and the PTFT is turned on based on a low-level signal and turned off based on a high-level signal; or, the function switching switch 221 can also be an NTFT, and the NTFT is turned on based on a high-level signal and cut off based on a low-level signal.

[0229] In this example, the control circuit 3 is arranged between the control signal terminal P3 of the touch chip 11 and the function switching switch 221, and can control the function switching switch 221 to turn on or off based on the control signal of the control signal terminal P3. Since the control circuit 3 is not only connected to the control terminal of the function switching switch 221, but also connected to the connection node between the function switching switch 221 and the touch electrode 222, when the touch electrode 222 can perform the coding process based on the coding signal of the touch chip 11, the coding potential change of the touch electrode 222 can be determined, and its control terminal potential can be adjusted based on the coding potential change to ensure the realization of the TSP function mode and the EMR function mode.

[0230] Embodiment 2

[0231] In one embodiment, as Figure 2 shown, each of the control circuits 223 includes a first capacitor C1 and a switch circuit 2231;

[0232] One end of the first capacitor C1 is connected to the control terminal of the function switching switch 221, and the other end of the first capacitor C1 is connected to the connection node between the function switching switch 221 and the touch electrode 222;

[0233] The first end of the switch circuit 2231 is used to connect to the reference voltage terminal VREF of the touch chip 11, the second end of the switch circuit 2231 is connected to the control terminal of the function switching switch 221, and the third end of the switch circuit 2231 is used to connect to the switch signal terminal SW of the touch chip 11;

[0234] The switch circuit 2231 is used to be turned on or off based on the control signal output from the switch signal terminal SW, and based on the reference voltage output from the reference voltage terminal VREF, control the function switching switch 221 to be turned on or off.

[0235] As an example, one end of the first capacitor C1 is connected to the control end of the function switching switch 221, and the other end of the first capacitor C1 is connected to the connection node between the function switching switch 221 and the touch electrode 222, so that the first capacitor C1 and the function switching switch 221 cooperate to form a bootstrap circuit. For example, when the function switching switch 221 is a TFT, the first capacitor C1 is arranged between the gate and the source of the function switching switch 221, so that the first capacitor C1 and the parasitic capacitance Cgs of the function switching switch 221.

[0236] In this example, since one end of the first capacitor C1 is connected to the control end of the function switching switch 221, and the other end of the first capacitor C1 is connected to the connection node between the function switching switch 221 and the touch electrode 222, the first capacitor C1 and the function switching switch 221 cooperate to form a bootstrap circuit. When the touch electrode 222 performs coding based on the coding signal of the touch chip 11, the potential of the control end of the function switching switch 221 can follow the coding potential of the touch electrode 222, so as to ensure the realization of the TSP function mode and the EMR function mode. For example, when it is necessary to control the touch screen 2 to enter the TSP function mode, the touch chip 11 can control the function switching switch 221 to be turned off, so that the touch electrode 222 receives the first coding signal of the touch chip 11. At this time, the control circuit 223 and the function switching switch 221 cooperate to control the gate voltage of the function switching switch 221 to follow the coding potential of the touch electrode 222, so that the off-state current of the function switching switch 221 is small, and the leakage current of the function switching switch 221 is avoided from affecting the TSP function mode of the touch screen 2.

[0237] In one embodiment, as Figure 2 shown, the common voltage line 21 is connected to the common voltage terminal P1 through the state switch 12;

[0238] The reference voltage includes a first reference voltage for controlling the function switching switch 211 to be turned off;

[0239] The switch circuit 2231 is used to be turned on based on the first control signal output from the switch signal terminal SW, and based on the first reference voltage output from the reference voltage terminal VREF, control the function switching switch 221 to be turned off, and initialize the potential of the control end of the function switching switch 221;

[0240] The switch circuit 2231 is further configured to be turned off based on a second control signal output from the switch signal terminal SW, so that the function switching switch 221 maintains a closed state, and the potential of the control terminal of the function switching switch 221 follows the coding potential change of the touch electrode 222;

[0241] When the state switch 12 is in a conducting state, the common voltage line 21 is configured to receive a common voltage output from the common voltage terminal P1, and the touch electrode 222 is configured to receive a first coding signal output from the coding signal terminal P2, so that the touch screen 2 enters the TSP function mode.

[0242] In some possible embodiments, when the function switching switch 221 is a TFT, the control process for the touch screen 2 to enter the TSP function mode is as follows:

[0243] (1) The switch signal terminal SW of the touch control chip 11 can output a first control signal to control the switch circuit 2231 to turn on; at the same time, the reference voltage terminal VREF of the touch control chip 11 can output a first reference voltage to the switch circuit 2231. When the switch circuit 2231 is turned on, the first reference voltage can be transmitted to the gate of the function switching switch 221 to control the function switching switch 221 to turn off.

[0244] In this example, when the first reference voltage is transmitted to the gate of the function switching switch 221, the gate potential of the function switching switch 221 can be initialized. At the same time, the corresponding touch electrode 222 also has an initial voltage. At this time, the initial voltage difference between the gate and the source of the function switching switch 221 can be determined. This initial voltage difference can ensure that the voltage Vgs between the gate and the source of the function switching switch 221 is less than the conduction threshold |Vthp|, so that the function switching switch 221 is in a closed state, and the voltage Vds between the drain and the source of the function switching switch 221 is also close to 0, so that the off-state current of the function switching switch 221 is very small. The initial voltage of the touch electrode 222 can be a fixed voltage close to the middle voltage of the coding waveform, for example, it can be the GND voltage.

[0245] (2) The switch signal terminal SW of the touch control chip 11 can output a second control signal to control the switch circuit 2231 to turn off, so that the gate of the function switching switch 221 is in a floating state. By using the bootstrap effect of the capacitor unit formed by the first capacitor C1 and the parasitic capacitor Cgs of the function switching switch 221 itself, the gate potential of the function switching switch 221 is maintained. When the TSP function mode enters the coding stage, the gate potential of the function switching switch 221 can follow the coding potential change, and it is ensured that the voltage Vgs between the gate and the source of the function switching switch 221 is less than the conduction threshold |Vthp|, so that the function switching switch 221 is in a closed state.

[0246] (3) When the function switching switch 221 is in the off state, the common voltage terminal P1 is used to output a common voltage to the common voltage line 21, and the coding signal terminal P2 of the touch control chip 11 can output a first coding signal to the coding signal terminal P2, so that the touch control electrode 222 can receive the first coding signal, enabling the touch screen 2 to enter the TSP function mode. During this process, the voltage Vgs of the function switching switch 221 changes with the coding potential, such that although the voltage Vds of the function switching switch 221 has a certain change, the final formed off-state current is small, so as to avoid the leakage current of the function switching switch 221 from affecting the realization of the TSP function mode.

[0247] In one embodiment, as Figure 2 shown, the reference voltage includes a second reference voltage for controlling the switch circuit 2231 to turn off;

[0248] When the switch circuit 2231 is turned off based on the second control signal output from the switch signal terminal SW, it is further used to maintain the off state based on the second reference voltage output from the reference voltage terminal VREF.

[0249] As an example, when the switch signal terminal SW of the touch control chip 11 outputs a second control signal to the third terminal of the switch circuit 2231 to turn off the switch circuit 2231, the reference voltage terminal VREF of the touch control chip 11 also outputs a second reference voltage to the first terminal of the switch circuit 2231, so as to adjust the voltage of the first terminal of the switch circuit 2231 to the GND voltage or a fixed voltage close to this value, to avoid the output signal of other circuits coupled to the first terminal of the switch circuit 2231 from changing the voltage of the first terminal of the switch circuit 2231, such that the switch circuit 2231 cannot maintain the off state and affects the realization of the TSP function mode.

[0250] In one embodiment, at least two of the touch control electrodes 222 corresponding to the same common voltage line 21 are used to receive the first coding signal output simultaneously by the coding signal terminal P2.

[0251] As an example, when the function switching switch 221 is turned off, a unidirectional channel is formed between the touch control chip 11 and multiple touch control electrodes 222, such that when the function switching switch 221 is in the off state, the touch control chip 11 can output a first coding signal to at least two touch control electrodes 222 corresponding to the same common voltage line 21 simultaneously through its coding signal terminal P2, so that at least two touch control electrodes 222 corresponding to the same common voltage line 21 can receive the first coding signal simultaneously (the timing is as Figure 5 、 Figure 12 、 Figure 14 and Figure 19As shown in the figure, to ensure the coding efficiency of the TSP function mode, during the coding process, due to the bootstrap effect of the capacitor unit formed between the first capacitor C1 and the parasitic capacitance Cgs of the function switching switch 221, the gate potential of the function switching switch 221 can be controlled to follow the change of its coding potential, so that the off-state current of the function switching switch 221 is relatively small.

[0252] In one embodiment, as Figure 2 shown, the common voltage line 21 is connected to the common voltage terminal P1 through the state switch 12;

[0253] The reference voltage includes a third reference voltage for controlling the opening of the function switching switch 221;

[0254] The switch circuit 2231 is further configured to be turned on based on the first control signal output by the switch signal terminal SW, and control the function switching switch 221 to be turned on based on the third reference voltage output by the reference voltage terminal VREF;

[0255] When the state switch 12 is in the off state, the touch electrode 222 is configured to receive the second coding signal output by the coding signal terminal P2, so that the touch screen 2 enters the EMR function mode.

[0256] As an example, when the function switching switch 221 is a TFT, the switch signal terminal SW of the touch control chip 11 can output a first control signal to control the switch circuit 2231 to be turned on. At the same time, the reference voltage terminal VREF of the touch control chip 11 can output a third reference voltage. When the switch circuit 2231 is turned on, the third reference voltage can be transmitted to the gate of the function switching switch 221, so that the voltage between the gate and the source of the function switching switch 221 is greater than or equal to the conduction threshold |Vthp|, and the third reference voltage can control the function switching switch 221 to be turned on. When the state switch 12 is in the off state (such as Figure 7 and Figure 18 the HiZ state in), that is, to control the common voltage line 21 to be in a floating state, the coding signal terminal P2 of the touch control chip 11 and at least two touch electrodes 222 on the same common voltage line 21 form a loop channel, and the touch electrode 222 can receive the second coding signal output by the touch control chip 11, so that the touch screen 2 enters the EMR function mode.

[0257] In one embodiment, as Figure 7 and Figure 8 shown, the common voltage line 21 includes a first common voltage line 211 to which at least three of the touch electrodes 222 are connected;

[0258] At least three of the touch electrodes 222 corresponding to the same first common voltage line 211 are configured to receive the second coding signals output by the coding signal terminal P2 one by one.

[0259] As an example, the common voltage line 21 may be the first common voltage line 211, and the first common voltage line 211 is the common voltage line 21 connected to at least three touch electrodes 222. In this example, one end of the first common voltage line 211 is used to connect to the common voltage terminal P1 of the touch chip 11; the first common voltage line 211 is also connected to at least three function switching switches 221, and each function switching switch 221 is connected to a touch electrode 222. When the state switch 12 is in the off state, that is, when the first common voltage line 211 is in a floating state, the first common voltage line 211 and at least three touch electrodes 222 cooperate to form a coil structure similar to a comb structure. Moreover, the second ends of at least three touch electrodes 222 corresponding to the same first common voltage line 211 are also connected to the coding signal terminal P2 of the touch chip 11, so that at least three touch electrodes 222 corresponding to the same first common voltage line 211 can receive the second coding signals output one by one by the touch chip 11, so as to ensure that only one touch electrode 222 performs coding based on the second coding signal at the same time, avoiding signal crosstalk. This method requires fewer common voltage lines 21, which helps to save costs and the occupied area.

[0260] In one embodiment, as Figure 10 and Figure 11 shown, the common voltage line 21 includes a second common voltage line 212 connected to two of the touch electrodes 222;

[0261] Two of the touch electrodes 222 corresponding to the same second common voltage line 212 are used to receive the second coding signals output simultaneously by the coding signal terminal P2.

[0262] As an example, the common voltage line 21 may be the second common voltage line 212, and the second common voltage line 212 is the common voltage line 21 connected to two touch electrodes 222. In this example, one end of the second common voltage line 212 is connected to the common voltage terminal P1 of the touch chip 11; the second common voltage line 212 is also connected to two function switching switches 221, and each function switching switch 221 is connected to a touch electrode 222. When the state switch 12 is in the off state, that is, when the second common voltage line 212 is in a floating state, a circular channel is formed between the two touch electrodes 222 corresponding to the second common voltage line 212 and the coding signal terminal P2 of the touch chip 11, so that the two touch electrodes 222 corresponding to the same second common voltage line 212 can receive the second coding signals output simultaneously by the touch chip 11, so that two touch electrodes 222 perform coding based on the second coding signal at the same time. This method can effectively shorten the coding time and helps to improve the coding efficiency.

[0263] In one embodiment, as Figure 3As shown, the switch circuit 2231 includes a first control switch TFT1;

[0264] The first end of the first control switch TFT1 is used to connect to the reference voltage terminal VREF of the touch chip 11, the second end of the first control switch TFT1 is connected to the control end of the function switching switch 221, and the control end of the first control switch TFT1 is used to connect to the switch signal terminal SW of the touch chip 11;

[0265] The first control switch TFT1 is used to be turned on based on a first control signal output by the switch signal terminal SW, or turned off based on a second control signal output by the switch signal terminal SW.

[0266] As an example, the switch circuit 2231 includes a first control switch TFT1. The first control switch TFT1 is arranged between the reference voltage terminal VREF of the touch chip 11 and the control end of the function switching switch 221. The control end of the first control switch TFT1 is connected to the switch signal terminal SW of the touch chip 11, and it can be turned on based on a first control signal output by the switch signal terminal SW of the touch chip 11 and turned off based on a second control signal output by the switch signal terminal SW of the touch chip 11. In this example, the first control switch TFT1 can be a PTFT, and the PTFT is turned on based on a low-level signal and turned off based on a high-level signal; alternatively, the first control switch TFT1 can also be an NTFT, and the NTFT is turned on based on a high-level signal and cut off based on a low-level signal.

[0267] As Figure 3 As shown, the control circuit 223 includes a switch circuit 2231 and a first capacitor C1. The two ends of the first capacitor C1 are respectively connected to the gate and source of the function switching switch 221, so that the first capacitor C1 cooperates with the function switching switch 221 to form a bootstrap circuit that can achieve a bootstrap effect. The switch circuit 2231 includes a first control switch TFT1. The first end of the first control switch TFT1 is connected to the reference voltage terminal VREF of the touch chip 11 and can receive the reference voltage VREF output by the touch chip 11; the second end of the first control switch TFT1 is connected to the gate of the function switching switch 221; the control end of the first control switch TFT1 is connected to the switch signal terminal SW of the touch chip 11, and it can control the first control switch TFT1 to be turned on or off according to different level signals output by the touch chip 11, so as to determine whether the reference voltage VREF provided by the touch chip 11 can be transmitted to the function switching switch 221, and control the function switching switch 221 to be turned on or off based on the reference voltage VREF.

[0268] In this example, the control circuit 223 includes a switching circuit 2231 and a first capacitor C1. The switching circuit 2231 includes a first control switch TFT1. The first control switch TFT1 and the first capacitor C1 cooperate to control the first control switch TFT1 to turn on based on the first control signal output by the touch chip 11. Based on the first reference voltage output by the touch chip 11 being transmitted to the gate of the function switching switch 221, when the function switching switch 221 is in the off state, the gate potential of the function switching switch 221 is initialized. And based on the second control signal output by the touch chip 11, the first control switch TFT1 is controlled to turn off, so that the function switching switch 221 remains in the off state. When the TSP function mode enters the coding stage, the first capacitor C1 and the function switching switch 221 cooperate to form a bootstrap circuit, which can make the gate potential of the function switching switch 221 follow the coding potential change of the touch electrode 222, so that the off-state current of the function switching switch 221 is small, so as to avoid the leakage current of the function switching switch 221 affecting the implementation of the TSP function mode.

[0269] For example, the touch electrode 222 can be a driving electrode TX or a sensing electrode RX. Taking the driving electrode TX as an example, the touch electrodes 222 in the two touch units 22 are respectively set as TFT1 / TFT2. The function switching switch 221 can be a PTFT or an NTFT. Taking the PTFT as an example, in this embodiment, the function switching switches 221 in the two touch units 22 are respectively set as PTFT1 / PTFT2. For the convenience of comparison, the function switching switches 221 in the two touch units 22 in the prior art are respectively set as PTFT3 / PTFT4. The first control switch TFT1 can be a PTFT or an NTFT. Taking the PTFT as an example, but in order to distinguish it from the PTFT in the function switching switch 221, the first control switches TFT1 in the two touch units 22 are respectively determined as TFT1 / TFT2. Figure 4 The left figure in is a schematic diagram of the touch screen 2 in this embodiment, and the right figure is a schematic diagram of the touch screen 2 in the prior art. Combining Figure 5 with the timing diagram of Figure 6 and the simulation diagram of

[0270] (1) Before entering the coding stage of the TSP function mode of the touch screen 2, the touch chip 11 outputs a low-level signal to the control terminal of the first control switch TFT1 / TFT2 to turn on the first control switch TFT1 / TFT2; at the same time, the touch chip 11 outputs the first reference voltage Vo to the first terminal of the first control switch TFT1 / TFT2. When the first control switch TFT1 / TFT2 is turned on, the first reference voltage Vo of the touch chip 11 can be transmitted to the gates N1 / N2 of the function switching switch PTFT1 / PTFT2 to control the function switching switch PTFT1 / PTFT2 to turn off. Specifically, the first reference voltage Vo is transmitted to the gates N1 / N2 of the function switching switch PTFT1 / PTFT2 for initialization. At the same time, there is also an initial voltage on the corresponding driving electrodes TX1 / TX2. The voltage difference between the first reference voltage Vo and the initial voltage of the touch electrodes TFT1 / TFT2 is small, so that the voltage Vgs of the function switching switch PTFT1 / PTFT2 < the conduction threshold |Vthp|. At this time, the function switching switch PTFT1 / PTFT2 is always kept in the off state, and the voltage Vds of the function switching switch PTFT1 / PTFT2 is also close to 0, making the off-state current of the function switching switch PTFT1 / PTFT2 very small. The initial voltage of the touch electrodes TFT1 / TFT2 can be a fixed voltage close to the intermediate voltage of the coding waveform, for example, it can be the GND voltage.

[0271] (2) After the gates N1 / N2 of the function switching switch PTFT1 / PTFT2 are initialized, the touch chip 11 outputs a high-level signal to the control terminal of the first control switch TFT1 / TFT2, gradually raising the level of the first control switch TFT1 / TFT2 to turn off the first control switch TFT1 / TFT2. At the same time, the touch chip 11 outputs a second reference voltage to the first control switch TFT1 / TFT2. The second reference voltage can be the GND voltage or a voltage close to this value to avoid interference from other circuits coupled to the first control switch TFT1 / TFT2, so that the switch circuit 2231 cannot maintain the off state and affect the realization of the TSP function mode; when the first control switch TFT1 / TFT2 is turned off, the gates N1 / N2 of the function switching switch PTFT1 / PTFT2 are in a floating state. Based on the cooperation of the first capacitors C11 / C12 and the parasitic capacitance Cgs of the function switching switch PTFT1 / PTFT2, the potential of the gates N1 / N2 of the function switching switch PTFT1 / PTFT2 is maintained.

[0272] (3) When the TSP function mode enters the coding stage, the coding signal terminal P2 of the touch chip 11 outputs a first coding signal to the driving electrodes TX1 / TX2, so that the driving electrodes TX1 / TX2 can receive the first coding signal. Since the parasitic capacitance Cgs of the first capacitors C11 / C12 and the function switching switches PTFT1 / PTFT2 can achieve the bootstrap effect, the potentials of the gates N1 / N2 of the function switching switches PTFT1 / PTFT2 change with the coding potentials of TX1 / TX2 respectively, and the voltage Vgs of the function switching switches PTFT1 / PTFT2 is maintained < the conduction threshold |Vthp|, so that the function switching switches PTFT1 / PTFT2 are turned off. Since the voltage Vgs of the function switching switches PTFT1 / PTFT2 is always in a small state with the change of the coding potential, even if its voltage Vds changes to a certain extent, the off-state current finally formed by it will be small, so as to avoid the leakage current of the function switching switches PTFT1 / PTFT2 from affecting the realization of the TSP function mode. In this example, when the touch chip 11 outputs the first coding signal to the driving electrodes TX1 / TX2, its common voltage terminal P1 also outputs a common voltage, and the common voltage here can be the GND voltage or a voltage close to this value, so as to maintain the off state of the function switching switches PTFT1 / PTFT2. Since a unidirectional channel is formed between the touch chip 11 and multiple touch electrodes TFT1 / TFT2 when the function switching switch 221 is turned off, the coding signal terminal P2 of the touch chip 11 can output the first coding signal to at least two driving electrodes TX1 / TX2, so that all the driving electrodes TX1 / TX2 can be coded simultaneously, ensuring the coding efficiency of the TSP function mode.

[0273] As Figure 4 shown, in the prior art, the gates of the function switching switches PTFT3 / PTFT4 are connected to the switch signal terminal SW of the touch chip 11, and the function switching switches PTFT3 / PTFT4 can be controlled to turn off based on the DC voltage output by the switch signal terminal SW, so that the gate potentials of the function switching switches PTFT3 / PTFT4 are fixed values. Although the voltage Vgs of the function switching switches PTFT3 / PTFT4 can be controlled < the conduction threshold |Vthp|, when the TSP function mode enters the coding stage, the voltage Vgs of the function switching switches PTFT3 / PTFT4 changes with the coding potential, resulting in a large fluctuation of the voltage Vgs of the function switching switches PTFT3 / PTFT4. Coupled with the change of the voltage Vds of the function switching switches PTFT3 / PTFT4, the leakage current of the function switching switches PTFT3 / PTFT4 is large during a 1 / 2T time period at different swing positions of the coding potential, causing mutual crosstalk between the driving electrodes TX1 / TX2, and thus affecting the TSP function mode.

[0274] As Figure 5 andFigure 6 As shown, under the control of a fixed DC voltage, the leakage current of the function switching switch PTFT3 / PTFT4 is relatively large, and it is shown in the figure that it is greater than 230 pA; while the function switching switches PTFT1 / PTFT2 and the first capacitors C11 / C12 form a bootstrap circuit, so that the gate potential of the function switching switches PTFT1 / PTFT2 will follow the coding potential change of the driving electrodes TX1 / TX2, so that the leakage current of the function switching switches PTFT1 / PTFT2 is always kept below 10 pA, so that the off-state current of the function switching switch 221 is small, so as to avoid the influence of the leakage current of the function switching switch 221 on the realization of the TSP function mode.

[0275] The working process of the control circuit 223 of the adjacent channels in the EMR function mode is as follows: Before the coding stage of the control touch screen 2 entering the EMR function mode, the touch control chip 11 outputs a low-level signal to the control end of the first control switches TFT1 / TFT2, so as to open the first control switches TFT1 / TFT2 and maintain the normally open state; at the same time, the touch control chip 11 outputs the third reference voltage to the first ends of the first control switches TFT1 / TFT2. When the first control switches TFT1 / TFT2 are opened, the third reference voltage of the touch control chip 11 can be transmitted to the gates N1 / N2 of the function switching switches PTFT1 / PTFT2 to control the function switching switches PTFT1 / PTFT2 to open.

[0276] In some possible implementation manners, such as Figure 7 As shown, when the touch control chip 11 outputs the third reference voltage, it is also necessary to control the state switch 12 to be disconnected, so that the common voltage terminal P1 of the touch control chip 11 is disconnected from the common voltage line 21, so that the common voltage line 21 is in a floating state, so that at least three touch electrodes 222 are connected together through the first common voltage line 211 to form a coil structure similar to a comb structure, and its equivalent result is as Figure 8 As shown, at this time, the nodes N1 to Nn are all in a low-level state to ensure that all function switching switches PTFT are in a fully open state; at least three touch electrodes 222 corresponding to the same first common voltage line 211 are connected to the coding signal terminal P2 of the touch control chip 11, and then the second coding signal is output to at least three touch electrodes 222 one by one through the control of the coding signal terminal P2, that is, a sine wave signal or an intermediate potential is provided for the touch electrodes 222 of a specific channel to determine the current direction of the comb structure, and then various electromagnetic field coil networks are formed to ensure that only one touch electrode 222 is coded based on the second coding signal at the same moment, avoiding signal crosstalk. This method requires fewer common voltage lines 21, which helps to save costs and the occupied area.

[0277] In another specific embodiment, when the touch control chip 11 outputs the third reference voltage, it is also necessary to control the state switch 12 to disconnect, so that the common voltage terminal P1 of the touch control chip 11 is disconnected from the common voltage line 21, making the common voltage line 21 in a floating state, and enabling the two touch electrodes 222 to be connected together through the second common voltage line 212. Figure 10 It shows an equivalent structure of different coil combinations by connecting two adjacent touch electrodes 222 together through the second common voltage line. Figure 11 It shows an equivalent structure of different coil combinations by connecting two different touch electrodes 222 together through the second common voltage line at a certain interval. The two touch electrodes 222 corresponding to the same second common voltage line 212 are connected to the coding signal terminal P2 of the touch control chip 11, so that the coding signal terminal P2 outputs the second coding signal to the two touch electrodes 222 simultaneously, ensuring that two touch electrodes 222 can be coded based on the second coding signal at the same moment. This method can effectively shorten the coding time and help improve the coding efficiency.

[0278] Such as Figure 12 As shown, from the complete working timing of the touch screen 2, its TSP function mode and EMR function mode work in a time-sharing manner, and different signals need to be output by the touch control chip 11 to control the touch screen 2 to complete the switching between the TSP function mode and the EMR function mode. In this example, after the touch control chip 11 controls the touch screen 2 to complete one TSP function mode and EMR function mode, it is necessary to control the touch screen 2 to complete an initialization operation again, that is, to initialize the control terminal potential (i.e., the gate potential) of the function switching switch 221 through the first reference voltage output by the reference voltage terminal VERF, to ensure the accuracy of the control process and avoid the cumulative error of multiple operations affecting the control accuracy.

[0279] In one embodiment, as Figure 13 shown, the switch circuit 2231 further includes a voltage boosting circuit 22311, and the voltage boosting circuit 22311 is connected to the connection node between the second end of the first control switch TFT1 and the control end of the function switching switch 221.

[0280] The voltage boosting circuit 22311 is also used to connect to the control signal terminal P3 of the touch control chip 11, and is used to boost the control signal in the second voltage range output by the common voltage terminal P1 and convert it into a control signal in the first voltage range to control the function switching switch 222 to open or close.

[0281] As an example, when the function switching switch 222 is a TFT, the first voltage range for controlling the opening or closing of the TFT is a relatively high voltage range (such as 3V - 8V). If the touch chip 11 is a touch chip 11 prepared based on a low-voltage manufacturing process, the touch chip 11 outputs a control signal in a second voltage range. At this time, a voltage boosting circuit 22311 needs to be set on the touch screen 2. The voltage boosting circuit 22311 is set between the control signal terminal P3 of the touch chip 11 and the control terminal of the function switching switch 221, and can boost the control signal in the second voltage range output from the common voltage terminal P1 to be converted into a control signal in the first voltage range to control the opening or closing of the function switching switch 222. In this example, since the voltage boosting circuit 22311 is set on the touch screen 2 for signal boosting, the voltage range for controlling the opening or closing of the control switch can be appropriately reduced. A touch chip 11 manufactured by a conventional low-voltage manufacturing process can be used to control the touch screen 2, instead of choosing a touch chip 11 manufactured by a particularly high-voltage manufacturing process, which helps to reduce the cost of the touch chip 11.

[0282] In one embodiment, as Figure 13 shown, the voltage boosting circuit 22311 includes a second control switch TFT2, a third control switch TFT3, a fourth control switch TFT4, a fifth control switch TFT5, and a second capacitor C2;

[0283] The second control switch TFT2, the third control switch TFT3, and the fourth control switch TFT4 are connected in series in sequence, and the fourth control switch TFT4 is connected to the control terminal of the function switching switch 221;

[0284] The control terminal of the first control switch TFT1 is used to connect to the first switch signal terminal SW1 of the touch chip 11 to receive the first switch signal output from the first switch signal terminal SW1;

[0285] The first end of the second control switch TFT2 is used to connect to the input terminal IN of the touch chip 11 to receive the first voltage output from the input terminal IN; the control terminal of the second control switch TFT2 is used to connect to the second switch signal terminal SW2 of the touch chip 11 to receive the second switch signal output from the second switch signal terminal SW2;

[0286] The control terminal of the third control switch TFT3 is used to connect to the negative voltage supply terminal VEE of the touch chip 11 to receive the VEE voltage output from the negative voltage supply terminal VEE;

[0287] The first terminal of the fifth control switch TFT5 is used to connect to the clock signal terminal CLK of the touch chip 11. The second terminal of the fifth control switch TFT5 is connected to the connection node between the third control switch TFT3 and the fourth control switch TFT4. The control terminal of the fifth control switch TFT5 is connected to the control terminal of the fourth control switch TFT4;

[0288] Both ends of the second capacitor C2 are respectively connected to the second terminal of the fifth control switch TFT5 and the control terminal of the fifth control switch TFT5;

[0289] The voltage boosting circuit 22311 is used to control the voltage boosting circuit 22311 to boost the voltage based on the first switch signal, the second switch signal, the first voltage, the VEE voltage, and the second voltage.

[0290] As an example, as Figure 18 shown, the first control switch TFT1 is used to connect to the first switch signal terminal SW1 of the touch chip 11. The voltage boosting circuit 22311 includes a second control switch TFT2, a third control switch TFT3, a fourth control switch TFT4, a fifth control switch TFT5, and a second capacitor C2. The second control switch TFT2, the third control switch TFT3, and the fourth control switch TFT4 are connected in series in sequence. The fourth control switch TFT4 is connected to the control terminal of the function switching switch PTFT1. The first terminal of the second control switch TFT2 is used to connect to the input terminal IN of the touch chip 11. The control terminal of the second control switch TFT2 is used to connect to the second switch signal terminal SW2 of the touch chip 11. The control terminal of the third control switch TFT3 is used to connect to the negative power supply terminal VEE of the touch chip 11. The control terminal of the fourth control switch TFT4 is connected to the control terminal of the fifth control switch TFT5. The first terminal of the fifth control switch TFT5 is used to connect to the clock signal terminal CLK of the touch chip 11. The second terminal of the fifth control switch TFT5 is connected to the connection node between the third control switch TFT3 and the fourth control switch TFT4. Both ends of the second capacitor C2 are respectively connected to the second terminal of the fifth control switch TFT5 and the control terminal of the fifth control switch TFT5.

[0291] In this example, the first control switch TFT1 can be controlled to turn on or off according to the first switch signal output from the first switch signal terminal SW1, and the second control switch TFT2 can be controlled to turn on or off according to the second switch signal output from the second switch signal terminal SW2. Then, combined with the reference voltage output from the reference voltage terminal VREF to the first control switch TFT1, the first voltage output from the input terminal IN to the second control switch TFT2, the VEE voltage output from the negative power supply terminal VEE to the third control switch TFT3, and the second voltage output from the clock signal terminal CLK to the fifth control switch TFT4, the voltage differences across each control switch are compared to control the third control switch TFT3, the fourth control switch TFT4, and the fifth control switch TFT5 to turn on or off, so as to achieve the purpose of voltage boosting while the TSP function mode and the EMR function mode are switched.

[0292] In one embodiment, the first control switch TFT1 is used to turn on based on the first control signal output from the first switch signal terminal SW1, and based on the first reference voltage output from the reference voltage terminal VREF, control the function switching switch 221 to turn off;

[0293] The second control switch TFT2 is used to turn on based on the first control signal output from the second switch signal terminal SW2, and based on the VDD voltage output from the input terminal IN and the GND voltage output from the clock signal terminal CLK, control the fourth control switch TFT4 and the fifth control switch TFT5 to turn off.

[0294] As an example, as Figure 14 and Figure 15 shown, the touch chip 11 sequentially performs the following operations to control the touch screen 2 to enter the TSP function mode:

[0295] The first control switch TFT1 turns on based on the first control signal output from the first switch signal terminal SW1, and transmits the reference voltage output from the reference voltage terminal VREF to the gate node (i.e., the N1 node) of the function switching switch PTFT1, so that the gate potential of the function switching switch PTFT1 is adjusted from the initial GND voltage to the reference voltage.

[0296] The second control switch TFT2 is turned on based on the first control signal output from the second switch signal terminal SW2 to transmit the VDD voltage output from the input terminal IN to the N3 node. The negative power supply terminal VEE outputs the VEE voltage to the third control switch TFT3, causing the third control switch TFT3 to be in an always-on state. At this time, the VDD voltage output from the input terminal IN can be transmitted to the N2 node. When the VDD voltage is greater than the reference voltage, the potential of the N2 node is higher than that of the N1 node, causing the fourth control switch TFT4 to be in a closed state throughout the TSP operating range, and the gate potential of the function switching switch PTFT can be initialized based on the reference voltage. Meanwhile, during this period, the N1 node is at a high potential, the second control switch TFT2 is turned off based on the second control signal output from the second switch signal terminal SW2, the N2 node is at a high potential, and the clock signal terminal CLK is used to output the GND voltage to the fourth control switch TFT4, causing the fifth control switch TFT5 to be turned off, ensuring that the off-state current of the fifth control switch TFT5 can also be minimized, reducing the static current consumption of the entire system.

[0297] In this example, when the touch control chip 11 controls the touch screen 2 to enter the TSP function mode, it first controls the first control switch TFT1 to be turned on based on the first control signal output from the first switch signal terminal SW1 to transmit the reference voltage output from the reference voltage terminal VREF to the N1 node, completing the initialization of the gate potential of the function switching switch PTFT1. After the other circuits in the circuit are initialized, they remain in a closed state. The process of the coding stage in the TSP function mode is the same as that in the coding stage of the TSP function mode in the above embodiment. To avoid repetition, it will not be elaborated here one by one.

[0298] In one embodiment, the first control switch TFT1 is used to be turned on based on the first control signal output from the first switch signal terminal SW1 and control the function switching switch 221 to be turned on based on the VEE voltage output from the reference voltage terminal VREF;

[0299] The second control switch TFT2 is used to be turned on based on the first control signal output from the second switch signal terminal SW2 to transmit the VEE voltage output from the input terminal IN to the node between the fourth control switch TFT4 and the fifth control switch TFT5, and the fifth control switch TFT5 receives the GND voltage output from the clock signal terminal CLK, causing the fourth control switch TFT4 to be turned off and the fifth control switch TFT5 to be turned on;

[0300] The first control switch TFT1 is used to turn off based on the second control signal output from the first switch signal terminal SW1. The second control switch TFT2 is used to turn off based on the second control signal output from the second switch signal terminal SW2. And the fifth control switch TFT5 receives the VEE voltage output from the clock signal terminal CLK to turn on the fourth control switch TFT4 and the fifth control switch TFT5.

[0301] As an example, as Figures 16 to 19 shown, the following control operations corresponding to the states are sequentially performed on the touch screen 2 to enable the touch screen 2 to enter the EMR function mode:

[0302] State 1: Based on the reference voltage output from the reference voltage terminal VREF, the first control switch TFT1 pulls down the potential of the first terminal of the first control switch TFT1 to the low level VEE. And the first control switch TFT1 turns on based on the first control signal output from the first switch signal terminal SW1, so that the N1 node maintains VEE + |Vthp|. Since PTFT1 is a unipolar PTFT, turning on at the lowest potential will result in a loss of |Vthp|.

[0303] State 2: The first terminal of the second control switch TFT2 receives the low level VEE output from the input terminal IN of the touch control chip 11. And the second control switch TFT2 turns on based on the first control signal output from the second switch signal terminal SW2, so that the low level VEE received by the first terminal of the second control switch TFT2 is adjusted by the third control switch TFT3 to adjust the potential of the N2 node to VEE + 2x|Vthp|. In this case, the fourth control switch TFT4 is a tube connected in the diode Connect mode, and its Vsg < |Vthp|, so that the fourth control switch TFT4 will not turn on, and thus the potential of the N1 node and the potential of the N2 node are maintained respectively. At the same time, the first terminal of the fifth control switch TFF5 receives the GND voltage output from the clock signal terminal CLK of the touch control chip 11, and the potential of the N2 node will control the fifth control switch TFT5 to turn on. Among them, the gate of the third control switch TFT3 is connected to the negative power supply terminal VEE, and it is only used as a limiting tube for reverse leakage current limitation.

[0304] State 3: The first control switch TFT1 is turned off based on the second control signal output from the first switch signal terminal SW1. The second control switch TFT2 is based on the second control signal output from the second switch signal terminal SW2, that is, the control signals of the first switch signal terminal SW1 and the second switch signal terminal SW2 are pulled high, causing the first control switch TFT1 and the second control switch TFT2 to turn off. The first terminal of the fifth control switch TFF5 is based on the control signal output from the clock signal terminal CLK, causing the first terminal of the fifth control switch TFF5 to change from the GND level to the VEE level. Since the fifth control switch TFT5 and the second capacitor C2 form a bootstrap structure, the potential of the N4 node will be pulled to the VEE potential, and the N2 node will also change from VEE + 2x|Vthp| to 2xVEE + 2x|Vthp|. At this time, since the Vsg of the fourth control switch TFT4 satisfies Vsg > |Vthp|, the potential of the N1 node is adjusted to 2xVEE + 3x|Vthp|. Based on this, the potential of the N1 node can be made less than the value of VEE through the above structure, which can meet the requirements of a larger drive voltage range.

[0305] The manufacturing processes used by the conventional touch chip 11 are all based on the VDD-VEE range, generally a low-voltage manufacturing process from +5V to -5V, while the voltage range of the high and low levels of the conventional PTFT is from +8V to -8V. Therefore, through the above circuit with a single-stage bootstrap, the control level of the N1 node can be lowered below the VEE level to better control the on-resistance Rdson of the PTFT1. Since the Vds of the PTFT1 is fixed, the lower the Vg, the smaller its Rdson. In this example, since the subsequent TX1 uses a sine wave signal in the EMR coding stage, a small part of the fluctuation is also coupled to the N1 node through the first capacitor C1, and a part of the jitter is also filtered through the fourth control switch TFT4, making the disturbance of the N2 node smaller. In this example, after the touch chip 11 controls the touch screen 2 to complete a TSP function mode and / or an EMR function mode, it is necessary to control the touch screen 2 to complete an initialization operation again, that is, to initialize the potential (i.e., the gate potential) of the control terminal of the function switching switch 221 through the reference voltage output from the reference voltage terminal VERF to ensure the accuracy of the control process and avoid the cumulative error of multiple operations affecting the control accuracy.

[0306] In this example, when the touch control chip 11 controls the touch screen 2 to enter the EMR function mode, the potentials of both the N1 node and the N2 node are first set low. Then, the potential of the clock signal terminal CLK is converted from the GND voltage to the VEE voltage. The bootstrap architecture formed by the fifth control switch TFT5 and the second capacitor C2 is used to pull the potential of the N2 node to a lower level, and a lower level is transmitted to the N1 node through the fourth control switch transistor TFT4, so as to complete the purpose of adjusting the N1 node to a level lower than VEE, thus achieving the purpose of controlling a larger driving voltage range by using a standard TP-IC process.

[0307] An embodiment of the present invention provides an electronic device, including the touch control chip 11 and the touch screen 2 in the above embodiment, and the touch control chip 11 is connected to the touch screen 2; or including the touch control device 1 and the touch screen 2 in the above embodiment, and the touch control device 1 is connected to the touch screen 2.

[0308] As an example, as Figure 20 and Figure 21 shown, the electronic device may include the touch control chip 11 and the touch screen 2 in the above embodiment, the touch control chip 11 is connected to the touch screen 2, and the touch control chip 11 is connected to the touch screen 2, and can control to enter the TSP function mode or the EMR function mode. The touch control chip 11 here may be provided with a built-in switch for controlling the common voltage terminal P1 to be in a floating state, and the touch control chip 11 is internally provided with a circuit for implementing the coding function, so that it can control the built-in switch to be opened or closed according to actual needs, and control the circuit for implementing the coding function to work, so as to switch to enter the TSP function mode or the EMR function mode.

[0309] As another example, as Figure 1 、 Figure 2 、 Figure 3 and Figure 8 shown, the electronic device may include the touch control device 1 and the touch screen in the above embodiment, and the touch control device 1 not only includes the touch control chip 11, but also includes at least one of a status switch 12, a coding circuit 13 and a power rail 14 for connecting the touch control chip 11 and the touch screen 2, so as to control the touch screen 2 to enter the TSP function mode or the EMR function mode through the touch control device 1.

[0310] The electronic device in the embodiments of the present application may be a portable or mobile computing device such as a terminal device, a mobile phone, a tablet computer and its accessory keyboard, a laptop computer, a desktop computer, a gaming device, an in-vehicle electronic device or a wearable intelligent device, as well as an electronic database, an automobile, a bank automated teller machine (ATM), and other electronic devices. The wearable intelligent device includes devices with complete functions and large sizes that can achieve complete or partial functions without relying on a smart phone, such as a smart watch or smart glasses, etc., and also includes devices that only focus on a certain type of application function and need to cooperate with other devices such as a smart phone, such as various smart bracelets and smart jewelry for vital sign monitoring.

[0311] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A touch chip for connecting to a touch screen, characterized in that, The touch screen includes a common voltage line and at least two touch units; each of the touch units includes a touch electrode, a function switching switch, and a control circuit; a first end of each touch electrode is connected to the common voltage line through a function switching switch; each control circuit is connected to a control end of the function switching switch and a connection node between the function switching switch and the touch electrode; The touch chip includes a common voltage terminal, a coding signal terminal, and a control signal terminal; The common voltage terminal is connected to the common voltage line; The coding signal terminal is connected to second ends of at least two touch electrodes; The control signal terminal is connected to the control circuit, and the control signal terminal is configured to output a control signal to the control circuit, so that the control circuit controls the function switching switch to be turned on or off.

2. The touch chip according to claim 1, wherein Each control circuit includes a first capacitor and a switch circuit; one end of the first capacitor is connected to the control end of the function switching switch, and the other end of the first capacitor is connected to the connection node between the function switching switch and the touch electrode; a second end of the switch circuit is connected to the control end of the function switching switch; The control signal terminal includes a reference voltage terminal and a switch signal terminal, the reference voltage terminal is connected to a first end of the switch circuit, and the switch signal terminal is connected to a third end of the switch circuit; The switch signal terminal outputs a control signal to the switch circuit to turn the switch circuit on or off, and the reference voltage terminal outputs a reference voltage to the switch circuit. Based on the reference voltage, the function switching switch is controlled to be turned on or off.

3. The touch chip according to claim 2, characterized in that, The common voltage terminal is connected to the common voltage line through a state switch; The reference voltage includes a first reference voltage for controlling the function switching switch to be turned off; The switch signal terminal is configured to output a first control signal to the switch circuit to turn the switch circuit on, and the reference voltage terminal is configured to output the first reference voltage to the switch circuit to control the function switching switch to be turned off and initialize the potential of the control end of the function switching switch; The switch signal terminal is configured to output a second control signal to the switch circuit to turn the switch circuit off, keep the function switching switch in the off state, and make the potential of the control end of the function switching switch follow the coding potential of the touch electrode; When the state switch is in the conducting state, the common voltage terminal is configured to output a common voltage to the common voltage line, and the coding signal terminal is configured to output a first coding signal to the touch electrode, so that the touch screen enters the TSP function mode.

4. The touch chip according to claim 3, wherein The reference voltage includes a second reference voltage for controlling the switch circuit to be turned off; When the switch signal terminal is configured to output a second control signal to the switch circuit, the reference voltage terminal outputs the second reference voltage to the switch circuit to keep the switch circuit in the off state.

5. The touch chip according to claim 3, wherein, The coding signal terminal is configured to output a first coding signal to at least two touch electrodes simultaneously.

6. The touch chip according to claim 2, wherein, The common voltage terminal is connected to the common voltage line through a state switch; The reference voltage includes a third reference voltage for controlling the function switching switch to turn on; The switch signal terminal is used to output a first control signal to the switch circuit to turn on the switch circuit, and the reference voltage terminal is used to output the third reference voltage to the switch circuit to control the function switching switch to turn on; When the status switch is in the off state, the coding signal terminal is used to output a second coding signal to the touch electrode to enable the touch screen to enter the EMR function mode.

7. The touch chip according to claim 6, wherein The common voltage line includes a first common voltage line connected to at least three touch electrodes; The coding signal terminal is used to sequentially output the second coding signal to at least three touch electrodes corresponding to the same first common voltage line.

8. The touch chip according to claim 6, wherein The common voltage line includes a second common voltage line connected to two touch electrodes; The coding signal terminal is used to simultaneously output the second coding signal to two touch electrodes corresponding to the same second common voltage line.

9. The touch control chip according to claim 2, wherein The switch circuit includes a first control switch, and the second end of the first control switch is connected to the control end of the function switching switch; The reference voltage terminal is connected to the first end of the first control switch, and the switch signal terminal is connected to the control end of the first control switch; The switch signal terminal outputs a first control signal to the first control switch to turn on the first control switch, or outputs a second control signal to the first control switch to turn off the first control switch.

10. The touch chip according to claim 9, characterized in that, The switch circuit further includes a voltage boosting circuit, and the voltage boosting circuit is connected to the connection node between the second end of the first control switch and the control end of the function switching switch; The control signal terminal is further used to be connected to the voltage boosting circuit to output a control signal in a second voltage range to the voltage boosting circuit, so that the voltage boosting circuit boosts the control signal in the second voltage range and converts it into a control signal in a first voltage range to control the function switching switch to turn on or off.

11. The touch chip according to claim 10, wherein The voltage boosting circuit includes a second control switch, a third control switch, a fourth control switch, a fifth control switch and a second capacitor; the second control switch, the third control switch and the fourth control switch are connected in series in sequence, and the fourth control switch is connected to the control end of the function switching switch; the second end of the fifth control switch is connected to the connection node between the third control switch and the fourth control switch, and the control end of the fifth control switch is connected to the control end of the fourth control switch; the two ends of the second capacitor are respectively connected to the second end of the fifth control switch and the control end of the fifth control switch; The switch signal terminal includes a first switch signal terminal and a second switch signal terminal; the control signal terminal further includes an input terminal, a negative voltage power supply terminal and a clock signal terminal; The first switch signal terminal is used to connect to the control end of the first control switch to output a first switch signal to the first control switch; the second switch signal terminal is used to connect to the control end of the second control switch to output a second switch signal to the second control switch; The input terminal is used to connect to the first end of the second control switch and output a first voltage to the second control switch; the negative power supply terminal is used to connect to the control end of the third control switch and output a VEE voltage to the third control switch; the clock signal terminal is used to connect to the first end of the fifth control switch and output a second voltage to the fifth control switch; based on the first switch signal, the second switch signal, the first voltage, the VEE voltage, and the second voltage, control the voltage boosting circuit to boost the voltage.

12. The touch chip according to claim 11, wherein The first switch signal terminal is used to output a first control signal to the first control switch to turn on the first control switch, and the reference voltage terminal is used to output a first reference voltage to the first control switch to turn off the function switching switch; The second switch signal terminal is used to output a first control signal to the second control switch to turn on the second control switch, the input terminal is used to output a VDD voltage to the second control switch, and the clock signal terminal is used to output a GND voltage to the fourth control switch to turn off the fourth control switch and the fifth control switch.

13. The touch chip according to claim 11, wherein, The first switch signal terminal is used to output a first control signal to the first control switch to turn on the first control switch, and the reference voltage terminal is used to output a VEE voltage to the first control switch to turn on the function switching switch; The second switch signal terminal is used to output a first control signal to the second control switch to turn on the second control switch, the input terminal outputs a VEE voltage to the second control switch, and the clock signal terminal outputs a GND voltage to the fifth control switch to turn off the fourth control switch and turn on the fifth control switch; The first switch signal terminal is used to output a second control signal to the first control switch to turn off the first control switch, the second switch signal terminal is used to output a second control signal to the second control switch to turn off the second control switch, and the clock signal terminal outputs a VEE voltage to the fifth control switch to turn on the fourth control switch and the fifth control switch.

14. The touch chip according to any one of claims 1-13, characterized in that, The touch chip is used to output a control signal within a first voltage range to the control circuit to control the control circuit to turn on or off the function switching switch.

15. A touch control device, characterized in that, Comprising the touch chip according to any one of claims 1-14 and a status switch; One end of the status switch is connected to the common voltage terminal of the touch chip, and the other end of the status switch is used to connect to the common voltage line of the touch screen.

16. The touch control device according to claim 15, characterized in that, The touch device further includes a coding circuit; One end of the coding circuit is connected to the coding signal terminal of the touch chip, and the other end of the coding circuit is used to connect to the touch electrode of the touch screen.

17. The touch control device according to claim 15, wherein The touch device further includes a power rail, one end of the power rail is connected to the control signal terminal of the touch chip, and the other end of the power rail is used to connect to the control circuit of the touch screen; The touch chip is used to output a control signal within a second voltage range; The power supply rail is used to convert the control signal of the second voltage range and output a control signal of the first voltage range to the control circuit, so that the control circuit controls the function switching switch to be turned on or off.

18. A touch screen for connecting to a touch chip, characterized in that, It includes a common voltage line and at least two touch units; Each of the touch units includes a touch electrode, a function switching switch and a control circuit; The first end of each touch electrode is connected to the common voltage line through a function switching switch, and the second end of each touch electrode is used to connect to the coding signal terminal of the touch chip; the common voltage line is used to connect to the common voltage terminal of the touch chip; Each control circuit is connected to the control terminal of the function switching switch and the connection node between the function switching switch and the touch electrode, and is also used to connect to the control signal terminal of the touch chip, and is used to control the function switching switch to be turned on or off according to the control signal output from the control signal terminal.

19. The touch screen according to claim 18, characterized in that, Each control circuit includes a first capacitor and a switch circuit; One end of the first capacitor is connected to the control terminal of the function switching switch, and the other end of the first capacitor is connected to the connection node between the function switching switch and the touch electrode; The first end of the switch circuit is used to connect to the reference voltage terminal of the touch chip, the second end of the switch circuit is connected to the control terminal of the function switching switch, and the third end of the switch circuit is used to connect to the switch signal terminal of the touch chip; The switch circuit is used to be turned on or off based on the control signal output from the switch signal terminal, and to control the function switching switch to be turned on or off based on the reference voltage output from the reference voltage terminal.

20. The touch screen according to claim 19, wherein, The common voltage line is connected to the common voltage terminal through a state switch; The reference voltage includes a first reference voltage for controlling the function switching switch to be turned off; The switch circuit is used to be turned on based on the first control signal output from the switch signal terminal, and to control the function switching switch to be turned off based on the first reference voltage output from the reference voltage terminal, and to initialize the potential of the control terminal of the function switching switch; The switch circuit is also used to be turned off based on the second control signal output from the switch signal terminal, so that the function switching switch maintains the off state, and the potential of the control terminal of the function switching switch follows the coding potential of the touch electrode; When the state switch is in the conducting state, the common voltage line is used to receive the common voltage output from the common voltage terminal, and the touch electrode is used to receive the first coding signal output from the coding signal terminal, so that the touch screen enters the TSP function mode.

21. The touch screen according to claim 20, characterized in that, The reference voltage includes a second reference voltage for controlling the switch circuit to be turned off; When the switch circuit is turned off based on the second control signal output from the switch signal terminal, it is also used to maintain the off state based on the second reference voltage output from the reference voltage terminal.

22. The touch screen according to claim 20, wherein, At least two touch electrodes corresponding to the same common voltage line are used to receive the first coding signal output by the coding signal terminal at the same time.

23. The touch screen according to claim 19, wherein, The common voltage line is connected to the common voltage terminal through a state switch; The reference voltage includes a third reference voltage for controlling the opening of the function switching switch; The switch circuit is further configured to be turned on based on a first control signal output from the switch signal terminal, and to control the function switching switch to be turned on based on the third reference voltage output from the reference voltage terminal; When the state switch is in the off state, the touch electrode is configured to receive a second coding signal output from the coding signal terminal, so that the touch screen enters the EMR function mode.

24. The touch screen according to claim 23, wherein, The common voltage line includes a first common voltage line connected to at least three of the touch electrodes; At least three of the touch electrodes corresponding to the same first common voltage line are configured to receive the second coding signals output one by one from the coding signal terminal.

25. The touch screen according to claim 23, wherein, The common voltage line includes a second common voltage line, and the second common voltage line is connected to two touch electrodes; The two touch electrodes corresponding to the same second common voltage line are configured to receive the second coding signals output simultaneously from the coding signal terminal.

26. The touch screen according to claim 19, wherein, The switch circuit includes a first control switch; A first end of the first control switch is configured to be connected to the reference voltage terminal of the touch chip, a second end of the first control switch is connected to a control end of the function switching switch, and a control end of the first control switch is configured to be connected to the switch signal terminal of the touch chip; The first control switch is configured to be turned on based on a first control signal output from the switch signal terminal, or turned off based on a second control signal output from the switch signal terminal.

27. The touch screen according to claim 26, wherein The switch circuit further includes a voltage boosting circuit, and the voltage boosting circuit is connected to a connection node between the second end of the first control switch and the control end of the function switching switch; The voltage boosting circuit is further configured to be connected to the control signal terminal of the touch chip, and is configured to boost a control signal in a second voltage range output from the common voltage terminal and convert it into a control signal in a first voltage range, so as to turn the switch circuit on or off.

28. The touch screen according to claim 27, wherein The voltage boosting circuit includes a second control switch, a third control switch, a fourth control switch, a fifth control switch, and a second capacitor; The second control switch, the third control switch, and the fourth control switch are connected in series in sequence, and the fourth control switch is connected to the control end of the function switching switch; The control end of the first control switch is configured to be connected to the first switch signal terminal of the touch chip to receive a first switch signal output from the first switch signal terminal; A first end of the second control switch is configured to be connected to the input terminal of the touch chip to receive a first voltage output from the input terminal; a control end of the second control switch is configured to be connected to the second switch signal terminal of the touch chip to receive a second switch signal output from the second switch signal terminal; The control end of the third control switch is configured to be connected to the negative power supply terminal of the touch chip to receive the VEE voltage output from the negative power supply terminal; A first end of the fifth control switch is configured to be connected to the clock signal terminal of the touch chip, a second end of the fifth control switch is connected to a connection node between the third control switch and the fourth control switch, and a control end of the fifth control switch is connected to the control end of the fourth control switch; Both ends of the second capacitor are respectively connected to the second end of the fifth control switch and the control end of the fifth control switch; The voltage boosting circuit is used to control the voltage boosting circuit to boost the voltage based on the first switch signal, the second switch signal, the first voltage, the VEE voltage, and the second voltage.

29. The touch screen according to claim 28, wherein The first control switch is used to be turned on based on the first control signal output from the first switch signal terminal, and to control the function switching switch to be turned off based on the first reference voltage output from the reference voltage terminal; The second control switch is used to be turned on based on the first control signal output from the second switch signal terminal, and to control the fourth control switch and the fifth control switch to be turned off based on the VDD voltage output from the input terminal and the GND voltage output from the clock signal terminal.

30. The touch screen according to claim 28, wherein The first control switch is used to be turned on based on the first control signal output from the first switch signal terminal, and to control the function switching switch to be turned on based on the VEE voltage output from the reference voltage terminal; The second control switch is used to be turned on based on the first control signal output from the second switch signal terminal, to transmit the VEE voltage output from the input terminal to the node between the fourth control switch and the fifth control switch, and the fifth control switch receives the GND voltage output from the clock signal terminal, so that the fourth control switch is turned off and the fifth control switch is turned on; The first control switch is used to be turned off based on the second control signal output from the first switch signal terminal, the second control switch is used to be turned off based on the second control signal output from the second switch signal terminal, and the fifth control switch receives the VEE voltage output from the clock signal terminal, so that the fourth control switch and the fifth control switch are turned on.

31. An electronic device, characterized in that, Comprising the touch chip according to any one of claims 1-14 and the touch screen according to any one of claims 18-30, wherein the touch chip is connected to the touch screen; Or, comprising the touch device according to any one of claims 15-17 and the touch screen according to any one of claims 18-30, wherein the touch device is connected to the touch screen.

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