Touch driving apparatus, driving method for touch driving apparatus, and touch controller

Abstract

The present invention relates to the technical field of touch control. Disclosed are a touch driving apparatus, a driving method for the touch driving apparatus, and a touch controller. The touch driving apparatus comprises an energy storage element and a driving module. The energy storage element is used for connecting to a driving end and for connecting a first target electrode and a second target electrode, wherein the first target electrode and the second target electrode are used for forming a driving coil, the first target electrode and the second target electrode are electrodes among a plurality of first electrodes on a touch screen, or the first target electrode and the second target electrode are electrodes among a plurality of second electrodes on the touch screen, the first electrodes are transmitting electrodes, and the second electrodes are receiving electrodes. The driving module comprises a driving end. The present invention can ensure the strength and consistency of excitation signals on the premise of fewer leads.

Description

Touch driver, driving method of touch driver and touch controller Technical Field

[0001] This invention relates to the field of touch technology, specifically to a touch driving device, a driving method for the touch driving device, and a touch controller. Background Technology

[0002] Touch screen panels can be classified into resistive, capacitive, infrared, or electromagnetic types according to their working principle. Electromagnetic touch screens have higher precision and pressure sensitivity than traditional capacitive and resistive touch screens, and are therefore widely used in digital drawing tablets, handwriting tablets for laptops, and smart whiteboards.

[0003] To reduce the number of pins required for electromagnetic detection, all the first coils in an electromagnetic touchscreen can be shorted at one end on the same side. However, with only one end of all the first coils shorted, the output excitation signal (or drive signal) exists across multiple first coils. This results in uneven distribution of the excitation signal among the different first coils, and signal loss also occurs, affecting the detection accuracy of the touch coordinates. Therefore, ensuring the strength and consistency of the excitation signal with fewer leads has become a pressing technical problem.

[0004] Summary of the Invention

[0005] In view of this, the present invention provides a touch driving device, a driving method for the touch driving device, and a touch controller to solve the problem of difficulty in ensuring the strength and consistency of the excitation signal with fewer leads.

[0006] In a first aspect, the present invention provides a touch driving device, comprising: an energy storage element for connecting to a driving end and for connecting to a first target electrode and a second target electrode; wherein the first target electrode and the second target electrode are used to form a driving coil, the first target electrode and the second target electrode are electrodes among a plurality of first electrodes on a touch screen, or the first target electrode and the second target electrode are electrodes among a plurality of second electrodes on a touch screen, the first electrode is a transmitting electrode, and the second electrode is a receiving electrode; and a driving module, comprising a driving end.

[0007] The touch driving device provided by the present invention, by setting an energy storage element, outputs a driving signal to the first coil (or the second coil) from the energy storage element during the driving period, which can achieve a "floating" effect, so that the driving signal (i.e., current) flows in the connected driving coil, avoiding the driving signal from entering other coils besides the driving coil, avoiding the problem of current shunting and mutual interference among multiple coils, thereby ensuring the strength and consistency of the driving signal with fewer leads and improving the detection accuracy of touch coordinates.

[0008] In one optional embodiment, the touch driving device further includes a first switch, a second switch, a third switch, and a fourth switch; one end of the first switch is connected to the driving end, the other end of the first switch is connected to the first end of the energy storage element, one end of the second switch is connected to the second end of the energy storage element, the other end of the second switch is grounded, one end of the third switch is connected to the first end of the energy storage element, the other end of the third switch is used to connect to the first target electrode, one end of the fourth switch is connected to the second end of the energy storage element, and the other end of the fourth switch is used to connect to the second target electrode.

[0009] In one alternative implementation, the first switch, the second switch, the third switch, the fourth switch, and the driving module are integrated on the touch chip, and the energy storage element is a first capacitor located outside the touch chip.

[0010] In one alternative implementation, the capacitance value of the first capacitor is greater than or equal to 100pF.

[0011] In one alternative implementation, the first switch, the second switch, the third switch, the fourth switch, the driving module, and the energy storage element are integrated on the touch chip, and the energy storage element is a second capacitor located inside the touch chip.

[0012] In one alternative implementation, the capacitance value of the second capacitor is less than 100pF.

[0013] In one optional embodiment, the drive module further includes a control unit; the control unit is used to control the first switch, the second switch, the third switch and the fourth switch to be turned on or off, so that the drive end charges the energy storage element and the energy storage element outputs an excitation signal to the drive coil.

[0014] In one optional embodiment, the number of energy storage elements is one, and multiple first electrodes form n first coils. The touch driving device further includes a first time-division multiplexer. The n first coils are connected to the energy storage element through the first time-division multiplexer. The first time-division multiplexer is used to connect the n first coils to the energy storage element in sequence. The driving coil is the coil among the n first coils that is connected to the energy storage element. Here, n is an integer greater than or equal to 2.

[0015] In this implementation, by setting a first time-division multiplexer, a single energy storage element can be used to complete the driving of touch detection, thereby realizing the detection of touch coordinates and reducing the cost of touch detection.

[0016] In one optional implementation, each touch scan includes n driving time periods, which include an alternately set first timing sequence and a second timing sequence. In the first timing sequence, the connection between the energy storage element and the driving terminal is turned on, and the connection between the energy storage element and the first target electrode and the second target electrode is turned off, and the energy storage element is charged to the driving voltage. In the second timing sequence, the connection between the energy storage element and the first target electrode and the second target electrode is turned on, and the connection between the energy storage element and the driving terminal is turned off, and the energy storage element outputs an excitation signal to the driving coil.

[0017] In one optional implementation, multiple first electrodes form n first coils, multiple second electrodes form n second coils, and the number of energy storage elements is a specified number. The touch chip also includes a second time-division multiplexer. The n first coils and n second coils are respectively connected to a specified number of energy storage elements through the second time-division multiplexer. The second time-division multiplexer is used to connect the odd-numbered or even-numbered coils among the n first coils to the energy storage elements, or the second time-division multiplexer is used to connect the odd-numbered or even-numbered coils among the n second coils to the energy storage elements. The driving coil is the coil among the n first coils or n second coils that is connected to the energy storage elements. Wherein, the specified number is n / 2 rounded up, and n is an integer greater than or equal to 2.

[0018] In this embodiment, the odd-even driving mode is used to realize touch detection, which can significantly reduce the scanning time of touch detection and thus improve the efficiency of touch detection.

[0019] In one optional implementation, each touch scan includes four driving time periods, which include an alternately set first timing sequence and a second timing sequence. In the first timing sequence, the connection between the energy storage element and the driving end is turned on, the connection between the energy storage element and the first target electrode and the second target electrode is turned off, and the energy storage element is charged to the driving voltage. In the second timing sequence, the connection between the energy storage element and the first target electrode and the second target electrode is turned on, the connection between the energy storage element and the driving end is turned off, and the energy storage element outputs an excitation signal to the driving coil.

[0020] In one alternative implementation, the resonant frequency of the drive coil is 80% to 120% of the resonant frequency of the inductor coil in the electromagnetic pen.

[0021] In one alternative implementation, the energy storage element is a third capacitor, the capacitance of which ranges from 50pF to 47UF.

[0022] In one optional embodiment, the touch driving device further includes a processing module, which is used to determine the touch coordinates of the electromagnetic pen based on the sensing signals detected by the multiple sensing coils during the stop driving time period; wherein, the multiple first electrodes form n first coils, the multiple second electrodes form n second coils, when the driving coil is a first coil, the sensing coil is n second coils, and when the driving coil is a second coil, the sensing coil is n first coils, where n is an integer greater than or equal to 2.

[0023] In this embodiment, the touch coordinates can be directly determined by detecting the sensing signal when coding stops, without the need for additional circuitry, thus reducing the cost of touch detection.

[0024] In one optional embodiment, the touch driving device further includes a processing module, which is used to determine the touch coordinates of the electromagnetic pen based on a reference signal and sensing signals detected by multiple sensing coils during the driving time period; wherein multiple first electrodes form n first coils, multiple second electrodes form n second coils, when the driving coil is a first coil, the sensing coil is n second coils, and when the driving coil is a second coil, the sensing coil is n first coils, where n is an integer greater than or equal to 2.

[0025] In this embodiment, the sensing signal can be detected while the driving coil receives the driving signal, without waiting, which can improve the efficiency of touch detection.

[0026] In a second aspect, the present invention provides a driving method for a touch driving device. The touch chip includes an energy storage element and a driving module. The energy storage element is used to connect to a driving end and to connect to a first target electrode and a second target electrode. The driving module includes a driving end. The first target electrode and the second target electrode are used to form a driving coil. The first target electrode and the second target electrode are electrodes among a plurality of first electrodes on a touch screen, or the first target electrode and the second target electrode are electrodes among a plurality of second electrodes on a touch screen. The first electrode is a transmitting electrode, and the second electrode is a receiving electrode. The method includes: in a first time sequence during an i-th driving time period, controlling the connection between the energy storage element and the driving end to be turned on, and controlling the connection between the energy storage element and the first target electrode and the second target electrode to be turned off, so that the energy storage element is charged to a driving voltage. The driving time period includes alternating first and second time sequences, i = 1, 2, ..., R, R ≥ 2, and i and R are integers. In a second time sequence during the i-th driving time period, controlling the connection between the energy storage element and the first target electrode and the second target electrode to be turned on, and controlling the connection between the energy storage element and the driving end to be turned off, so that the energy storage element outputs an excitation signal to the driving coil.

[0027] In one alternative implementation, before the connection between the energy storage element and the drive end is turned on during the first time sequence of the i-th drive time period, the method further includes: determining a drive mode, wherein the drive mode includes a turn-by-turn drive mode and an odd-even drive mode, wherein in the turn-by-turn drive mode, R = n, and in the odd-even drive mode, R = 4.

[0028] Thirdly, the present invention provides a touch controller, comprising: the touch driving device of the first aspect above or any corresponding embodiment thereof. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 is a schematic diagram of a touch screen according to an embodiment of the present invention;

[0031] Figure 2 is a schematic diagram of another touch screen according to an embodiment of the present invention;

[0032] Figure 3 is a schematic diagram of a single-turn first coil and a single-turn second coil according to an embodiment of the present invention;

[0033] Figure 4 is a schematic diagram of a multi-turn first coil and a multi-turn second coil according to an embodiment of the present invention;

[0034] Figure 5 is a schematic diagram of the connection relationship between a first coil and a second coil according to an embodiment of the present invention;

[0035] Figure 6 is a schematic diagram of the distribution of driving signals under one feasible driving scheme for an electromagnetic touch screen.

[0036] Figure 7 is a schematic diagram of a feasible driving scheme for an electromagnetic touch screen;

[0037] Figure 8 is a schematic diagram of a touch driving device according to an embodiment of the present invention;

[0038] Figure 9 is a schematic diagram of another touch driving device according to an embodiment of the present invention;

[0039] Figure 10 is a schematic diagram of the positional relationship between a touch chip and a touch driving device according to an embodiment of the present invention;

[0040] Figure 11 is a schematic diagram of another positional relationship between the touch chip and the touch driving device according to an embodiment of the present invention;

[0041] Figure 12 is a schematic diagram of the connection relationship between an energy storage element and a first electrode according to an embodiment of the present invention;

[0042] Figures 13 to 16 are schematic diagrams showing the connection relationship between the energy storage element and the first electrode under various timing conditions according to embodiments of the present invention;

[0043] Figure 17 is a schematic diagram of the structure of a first time-division multiplexer according to an embodiment of the present invention;

[0044] Figure 18 is a schematic diagram of the driving voltage waveform of the driving coil according to an embodiment of the present invention;

[0045] Figure 19 is a schematic diagram of the drive current waveform of the drive coil according to an embodiment of the present invention;

[0046] Figure 20 is a schematic diagram of the waveform of the electrode corresponding to the driving coil according to an embodiment of the present invention;

[0047] Figure 21 is a schematic diagram of the touch detection timing in the alternating drive mode according to an embodiment of the present invention;

[0048] Figures 22 to 25 are schematic diagrams showing the connection relationship between the energy storage element and the first electrode or the second electrode under various timing conditions according to embodiments of the present invention.

[0049] Figure 26 is a schematic diagram of the touch detection timing in the odd-even driving mode according to an embodiment of the present invention;

[0050] Figure 27 is a schematic diagram of the capacitor charge-discharge curve during the driving time period according to an embodiment of the present invention;

[0051] Figure 28 is a schematic diagram of the circuit model of the coupling between the driving coil and the inductor coil in the electromagnetic pen according to an embodiment of the present invention;

[0052] Figure 29 is a schematic diagram of driving signals and sensing signals under a driving timing according to an embodiment of the present invention;

[0053] Figure 30 is a schematic diagram of the driving signal and sensing signal under another driving timing according to an embodiment of the present invention;

[0054] Figure 31 is a schematic diagram of the connection relationship between the electrode corresponding to the sensing coil and the touch controller according to an embodiment of the present invention.

[0055] Figure 32 is a schematic diagram of a mean amplification module according to an embodiment of the present invention;

[0056] Figure 33 is a schematic diagram of another mean amplification module according to an embodiment of the present invention;

[0057] Figure 34 is a schematic diagram of another mean amplification module according to an embodiment of the present invention;

[0058] Figure 35 is a schematic diagram of another mean amplification module according to an embodiment of the present invention;

[0059] Figure 36 is a flowchart illustrating a driving method for a touch driving device according to an embodiment of the present invention;

[0060] Figure 37 is a schematic diagram of a display device according to an embodiment of the present invention;

[0061] Figure 38 is a schematic diagram of another display device according to an embodiment of the present invention.

[0062] Reference numerals: 110, First electrode; 120, Second electrode; 200, Touch chip; 210, Analog front-end circuit; 211, Filter; 212, Sample and hold module; 213, Buffer of analog-to-digital converter; 214, Analog-to-digital converter; 220, Touch driver; 221, Energy storage element; 222, Driver module; 223, First time-division multiplexer; 224, Processing module; 230, Cross-group amplifier; 240, Accumulator module; 250, Mean amplifier module; 260, Self-... Mutual capacitance mode switching module; 270, average analog front-end circuit; 311, single-turn first coil; 312, single-turn second coil; 411, multi-turn first coil; 412, multi-turn second coil; 610, excitation source; 3711, polyimide substrate; 3712, glass substrate; 372, thin film transistor layer; 373, light-emitting unit; 374, cathode plate; 375, light-emitting unit encapsulation layer; 376, touch screen; 377, polarizer; 3781, flexible cover plate; 3782, glass cover plate. Detailed Implementation

[0063] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0064] In the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concepts of the present invention. Various structural schematic diagrams according to embodiments of the present invention are shown in the accompanying drawings. These drawings are not to scale, and some details are enlarged for clarity, and some details may be omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed. In the context of the present invention, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. Additionally, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "below" the other layer / element.

[0065] Touchscreens, as an input medium, are currently a relatively simple and convenient human-computer interaction method, widely used in electronic devices such as mobile phones, tablets, and computers. Based on their working principle and the medium through which information is transmitted, touchscreens can be categorized into resistive, capacitive, infrared, and electromagnetic types. Electromagnetic touchscreens offer advantages such as high precision, high pressure sensitivity, Z-axis sensing capability, and high light transmittance, and have found widespread application in various fields. Electromagnetic touchscreens can be derived from capacitive touchscreens.

[0066] As shown in Figure 1, the touch screen may include multiple first electrodes 110 and multiple second electrodes 120. The multiple first electrodes 110 are connected to the touch controller 200 through multiple first leads, and the multiple second electrodes 120 are connected to the touch controller 200 through multiple second leads.

[0067] For example, the first electrode 110 can be a transmitting electrode (TX) and the second electrode 120 can be a receiving electrode (RX), and vice versa, that is, the first electrode can also be a receiving electrode and the second electrode can be a transmitting electrode.

[0068] Specifically, multiple first electrodes 110 and multiple second electrodes 120 are staggered and distributed below the glass cover in the touch screen. For example, as shown in Figure 1, the first electrodes and the second electrodes are distributed in a vertically intersecting manner, but are not limited thereto.

[0069] In this design, multiple first electrodes are distributed on the same plane (denoted as the first plane), and multiple second electrodes are distributed on another plane (denoted as the second plane). The first plane and the second plane are stacked vertically and located below the glass cover. For example, multiple first electrodes 110 extend along a first direction, and multiple second electrodes 120 extend along a second direction. The first direction and the second direction are perpendicular to each other, and there is a mutual capacitance at the intersection of each first electrode and second electrode. In this case, the touch screen can be a capacitive touch screen.

[0070] It should be understood that the distribution of the first electrode 110 and the second electrode 120 in a mutually perpendicular manner is only one possible implementation of the coupling capacitor and should not constitute any limitation on the present invention. As long as there is an intersection point between each first electrode 110 and each second electrode 120 that can generate mutual capacitance, and the intersection points of the plurality of first electrodes 110 and the plurality of second electrodes 120 can be evenly distributed below the touch screen, they should all fall within the protection scope of the present invention.

[0071] In Figure 1, taking the first electrode as the transmitting electrode and the second electrode as the receiving electrode as an example, TX0 to TX0 in Figure 1... n This refers to multiple first electrodes 110, RX0 to RX0 in Figure 1. n This represents multiple second electrodes 120, where n is an integer greater than or equal to 2. The connection between the first electrode 110 and the touch chip 200 is only schematic; the specific connection relationship can be configured by technicians according to requirements and will not be described here.

[0072] During touch detection, the driving module within the touch chip 200 outputs driving signals (also called excitation signals) to multiple first electrodes 110, such as square waves, stepped waves, or sine waves. The analog front end (AFE) within the touch chip 200 receives sensing signals (such as capacitance signals) detected by multiple second electrodes 120. Based on the changes in the sensing signals, touch detection of the touch screen is achieved, as well as the identification of the touch position (also called touch coordinates).

[0073] Further, as shown in Figure 2, at least two first electrodes and at least two second electrodes can be connected via a switch. When the switch is on, the connected first electrodes form a first coil, and the connected second electrodes form a second coil. At this time, the touch screen is transformed into an electromagnetic touch screen. During touch detection, the driving module of the touch chip 200 outputs driving signals (also called excitation signals) to multiple first coils. The analog front-end circuit (AFE) of the touch chip 200 receives the sensing signals (e.g., electromagnetic signals or current signals) detected by multiple second coils and identifies the touch coordinates based on the changes in the sensing signals.

[0074] The number of electrodes forming a first coil (or a second coil) is determined according to actual needs. For example, as shown in Figure 3, multiple first electrodes can be connected in pairs via a switch to form multiple single-turn first coils 311, and multiple second electrodes can be connected in pairs via a switch to form multiple single-turn second coils 312. As another example, as shown in Figure 4, two or more (e.g., six) first electrodes can also be connected via a switch to form multiple multi-turn first coils 411, and two or more second electrodes can be connected via a switch to form multiple multi-turn second coils 412.

[0075] In touchscreens based on electromagnetic detection, to reduce the number of PINs required for electromagnetic detection, as shown in Figure 5, multiple first electrodes 110 are connected to the touchscreen chip 200 at one end in a first direction via multiple first leads, and the other ends of the multiple first electrodes 110 are electrically connected, i.e., multiple first electrodes (TX0 to TX0) n The other ends of the multiple first coils formed are short-circuited through electrodes. Figure 5 uses a single-turn coil as an example; two adjacent first electrodes form one first coil, i.e., TX. i-1 and TX i The i-th first coil is formed, where 1≤i≤n, and i and n are integers, and n≥2. For example, TX0 and TX1 form the first first coil, and TX1 and TX2 form the second first coil. The upper ends of all the first coils in Figure 5 are shorted.

[0076] In addition, multiple second electrodes (RX0 to RX) n One end of the second direction is connected to the analog front-end circuit 210 of the touch chip 200 through n+1 second leads, and multiple second electrodes 120 can also be shorted together at the other end of the second direction (e.g., the left end) through electrodes.

[0077] In the above method, when a drive signal is input to the first coil, there are problems of insufficient drive signal strength and inconsistency.

[0078] Specifically, as shown in Figures 6 and 7, one port of the first coil is connected to the excitation source 610 in turn to receive the drive signal, while the ports of the remaining first coils are grounded (GND). Since the upper ends of all the first coils are short-circuited, the output drive current (i.e., drive signal) exists in n first coils of different sizes. There is an uneven distribution of drive current among the n first coils of different sizes. For example, as shown in Figure 6, the excitation source 610 is located in the first first coil, and the drive current in the second first coil is less than that in the first first coil (the impedance of the second first coil is greater). This causes the touch screen to have problems with inconsistent signals at different distances and mutual interference. Moreover, due to the current being shunted by the other first coils, the drive signal of a single first coil is lost, which affects the detection accuracy of the touch coordinates.

[0079] In view of this, the present invention provides a touch driving device that, by introducing an energy storage element, can ensure the strength and consistency of the excitation signal with fewer leads.

[0080] The touch driving device provided by this invention can be applied to fields such as electromagnetic touch screens or electronic devices containing electromagnetic touch screens. Electronic devices containing electromagnetic touch screens can be mobile phones, laptops, or computers, etc., and electromagnetic touch screens can be smart whiteboards or vehicle touch screens, etc.

[0081] The touch driving device provided by the present invention will now be described in detail with reference to the accompanying drawings.

[0082] As shown in Figure 8, the touch driving device 220 includes an energy storage element 221 and a driving module 222. The driving module 222 includes a driving end, which provides electrical energy to the energy storage element 221 through the driving end. The energy storage element 221 is used to connect to the driving end of the driving module 222 and to connect to the first target electrode and the second target electrode.

[0083] The first target electrode and the second target electrode are used to form a driving coil. The first target electrode and the second target electrode are electrodes among a plurality of first electrodes 110 on the touch screen, or the first target electrode and the second target electrode are electrodes among a plurality of second electrodes 120 on the touch screen.

[0084] Specifically, multiple first electrodes 110 form multiple first coils, multiple second electrodes 120 form multiple second coils, and the driving coil is one of the multiple first coils (or multiple second coils) that is connected to the energy storage element 221 and receives the driving signal output by the energy storage element 221.

[0085] When the coil formed by the first electrode (or the second electrode) is a single-turn coil, the first target electrode and the second target electrode can be two adjacent electrodes from a plurality of first electrodes (or second electrodes). For example, as shown in Figure 8, the first target electrode and the second target electrode can be TX0 and TX1 respectively. In this case, TX0 and TX1 form a driving coil, and the first target electrode and the second target electrode can also be TX0 and TX1 respectively. i-1 and TX i When the coil formed by the first electrode (or the second electrode) is a multi-turn coil, the first target electrode and the second target electrode can be the input and output electrodes of the multi-turn coil formed by the multiple first electrodes (or second electrodes).

[0086] It should be noted that Figure 8 uses the formation of a single-turn coil by electrodes as an example, with multiple first electrodes 110 (TX0 to TX). n Form n first coils and multiple second electrodes 120 (RX0 to RX) n(This can form n second coils, but is not limited to this.)

[0087] Based on the touch driving device provided by the present invention, when performing touch detection, the energy storage element 221 is charged by the driving module 222. After the voltage of the energy storage element 221 reaches the driving voltage, the energy storage element 221 outputs an excitation signal (or driving signal) to the driving coil formed by the first target electrode and the second target electrode.

[0088] The touch driving device provided by the present invention, by setting an energy storage element, outputs a driving signal to the first coil (or the second coil) from the energy storage element during the driving period, which can achieve a "floating" effect, so that the driving signal (i.e., current) flows in the connected driving coil, avoiding the driving signal from entering other coils besides the driving coil, avoiding the problem of current shunting and mutual interference among multiple coils, thereby ensuring the strength and consistency of the driving signal with fewer leads and improving the detection accuracy of touch coordinates.

[0089] Specifically, the capacitor is similar to a dry cell battery. The "floating" effect means that the first and second electrodes are connected through the capacitor, so there is no need to ground them. The floating setting can effectively prevent current from flowing to other coils besides the drive coil, thereby avoiding current shunting and interference from other coils to the drive coil.

[0090] For example, the present invention does not limit the specific structure of the energy storage element 221, as long as it can store electrical energy and provide pulse signals (i.e., drive signals) to the drive coil. For example, the energy storage element 221 can be a capacitor or the like.

[0091] To facilitate efficient control of the driving timing during touch detection, as shown in Figure 9, the touch driving device 220 also includes a first switch S1, a second switch S2, a third switch S3, and a fourth switch S4.

[0092] One end of the first switch S1 is connected to the drive terminal V. tx The other end of the first switch S1 is connected to the first end of the energy storage element 221, that is, the first end of the energy storage element 221 is connected in series with the first switch S1 and then connected to the drive terminal V. txOne end of the second switch S2 is connected to the second end of the energy storage element 221, and the other end of the second switch S2 is grounded. That is, the second end of the energy storage element 221 is connected to the ground after being connected in series with the second switch S2. One end of the third switch S3 is connected to the first end of the energy storage element 221, and the other end of the third switch S3 is used to connect to the first target electrode. That is, the first end of the energy storage element 221 is connected to the first target electrode after being connected in series with the third switch S3. One end of the fourth switch S4 is connected to the second end of the energy storage element 221, and the other end of the fourth switch S4 is used to connect to the second target electrode. That is, the second end of the energy storage element 221 is connected to the second target electrode after being connected in series with the fourth switch S4.

[0093] For example, the drive module 222 also includes a control unit, which controls the first switch S1, the second switch S2, the third switch S3 and the fourth switch S4 to turn on or off, so that the drive end charges the energy storage element 221 and the energy storage element 221 outputs an excitation signal to the drive coil.

[0094] Specifically, the control terminals of the first switch S1, the second switch S2, the third switch S3, and the fourth switch S4 can be connected to the control unit, and the switching devices can be turned on (closed) or off (opened) by the electrical signals output by the control unit. This invention does not limit the specific structure of the control unit; for example, the control unit can be a digital controller.

[0095] For example, the first switch S1, the second switch S2, the third switch S3 and the fourth switch S4 can be metal-oxide-semiconductor field-effect transistors (MOS).

[0096] Based on the touch driving device provided by the present invention, during touch detection, in the first timing sequence of the driving time period (coding time period), the first switch S1 and the second switch S2 are turned on, so that the connection between the energy storage element 221 and the driving end is turned on, and the third switch S3 and the fourth switch S4 are turned off, so that the connection between the energy storage element 221 and the first target electrode and the second target electrode is turned off. At this time, the energy storage element 221 is charged to the driving voltage. In the second timing sequence of the driving time period, the first switch S1 and the second switch S2 are turned off, so that the connection between the energy storage element 221 and the driving end is turned off, and the third switch S3 and the fourth switch S4 are turned on, so that the connection between the energy storage element 221 and the first target electrode and the second target electrode is turned on. At this time, the energy storage element 221 outputs a driving signal (or excitation signal) to the first coil (or the second coil) connected to it.

[0097] The driving time period includes multiple first timing sequences and multiple second timing sequences. The first timing sequences and second timing sequences are set alternately. The switching frequency of the first timing sequence and the second timing sequence can be set by technicians according to their needs. For example, the switching frequency of the first timing sequence and the second timing sequence can be 350KHz.

[0098] The positional relationship between the touch driving device 220 and the touch chip 200 provided by the present invention will be described below with reference to the accompanying drawings.

[0099] In some optional implementations, as shown in FIG10, the first switch S1, the second switch S2, the third switch S3, the fourth switch S4 and the driving module 222 are integrated on the touch chip 200, and the energy storage element 221 is the first capacitor C1 connected to the touch chip 200, that is, the energy storage element 221 is located outside the touch chip 200.

[0100] For example, the capacitance value of the first capacitor C1 is greater than or equal to 100pF.

[0101] In this embodiment, placing the first capacitor C1 externally can reduce the manufacturing cost of the touch chip 200, allow for more flexible selection of capacitors with different specifications and performance, and facilitate circuit optimization and adjustment.

[0102] In some alternative embodiments, as shown in FIG11, the first switch S1, the second switch S2, the third switch S3, the fourth switch S4, the driving module 222 and the energy storage element 221 can also be integrated on the touch chip 200. The energy storage element 221 is the second capacitor C2 located inside the touch chip 200, that is, the energy storage element 221 is located inside the touch chip 200.

[0103] For example, the capacitance value of the second capacitor C2 is less than 100pF.

[0104] In this embodiment, the second capacitor C2 is also integrated into the touch chip 200, which reduces the impact of external interference on capacitor performance, improves the stability and reliability of capacitor operation, and thus provides more accurate drive signals to the electrodes. Moreover, due to the tight integration of the second capacitor C2 with components such as the drive module 222, the connection lines are shorter, and the signal transmission loss is relatively small.

[0105] Specifically, the connection method between the energy storage element 221 and the first coil (or the second coil) and the position of the drive coil are determined based on the drive mode. The drive mode includes alternating drive mode and odd-even drive mode. The connection method between the energy storage element 221 and the first coil (or the second coil) and the position of the drive coil are described in detail below with reference to the accompanying drawings.

[0106] It should be noted that the following description uses the single-turn coil structure in Figure 8 and the energy storage element 221 as the first capacitor C1 as an example, but it is not limited to this.

[0107] Specifically, the alternating drive mode refers to the driving method in which n first coils formed by multiple first electrodes are sequentially connected to the energy storage element 221 to receive drive signals, thereby realizing touch coordinate detection.

[0108] In the case of a sequential drive mode, in some optional embodiments, as shown in Figure 12, the number of energy storage elements 221 is one. The touch drive device also includes a first time-division multiplexer 223, through which n first coils are connected to the energy storage element 221. The first time-division multiplexer 223 is used to connect the n first coils sequentially to the energy storage element 221, and the drive coil is the coil among the n first coils that is connected to the energy storage element. The number of first switches S1, second switches S2, third switches S3, and fourth switches S4 connected to the energy storage element 221 is also one.

[0109] For example, taking n=4 as an example, the alternating drive mode is explained as follows: As shown in Figure 13, in the first drive period (i.e., the first driving time period), the first coil (i.e., the coil formed by TX0 and TX1) is connected to the energy storage element 221, and the electrodes other than TX0 and TX1 are grounded. At this time, the first target electrode and the second target electrode mentioned above can be TX0 and TX1, respectively. As shown in Figure 14, in the second drive period (i.e., the second driving time period), the second coil (i.e., the coil formed by TX1 and TX2) is connected to the energy storage element 221. As shown in Figure 15, in the third drive period (i.e., the third driving time period), the third coil (i.e., the coil formed by TX2 and TX3) is connected to the energy storage element 221. As shown in Figure 16, in the fourth drive period (i.e., the fourth driving time period), the fourth coil (i.e., the coil formed by TX3 and TX4) is connected to the energy storage element 221. The driving coils are the first coil, the second coil, the third coil, and the fourth coil in sequence.

[0110] It should be noted that the present invention does not limit the order in which the n first coils are driven. For example, the driving coils can also be the fourth first coil, the third first coil, the second first coil, and the first first coil in sequence. When the driving coils receive the driving signal, all the second coils detect the induced signal.

[0111] This embodiment does not limit the specific structure of the first time-division multiplexer 223, as long as it enables the n first coils to be connected to the energy storage element 221 in sequence. For example, as shown in Figure 17, the first time-division multiplexer 223 may include n+1 single-pole double-throw switches S5. During the first driving time period, the first single-pole double-throw switch S5 is connected to the positive terminal (+1 terminal), the second single-pole double-throw switch S5 is connected to the negative terminal (-1 terminal), and the other single-pole double-throw switches S5 are grounded (connected to the 0 terminal), so that the first first coil (i.e., the coil formed by TX0 and TX1) is connected to the energy storage element, and the electrodes of the other coils except the first first coil are grounded.

[0112] In this embodiment, by setting a first time-division multiplexer 223, the driving during touch detection can be completed using a single energy storage element 221, thereby realizing the detection of touch coordinates and reducing the cost of touch detection.

[0113] In the case of a sequential drive mode, in some alternative embodiments, the number of energy storage elements 221 is n, and n first coils formed by multiple transmitting electrodes are connected one-to-one with the n energy storage elements 221. The drive coil is at least one of the n first coils. The number of first switches S1, second switches S2, third switches S3, and fourth switches S4 connected to the energy storage elements 221 is also n.

[0114] Specifically, when the driving mode is the alternating driving mode, the number of driving time periods required to complete the touch detection is the number of the first coils. In this embodiment, the number of the first coils is n, and each touch scan includes n driving time periods. The driving time periods include alternating first timing and second timing.

[0115] In the first timing sequence, the connection between the energy storage element 221 and the driving terminal is turned on, and the connection between the energy storage element 221 and the first target electrode and the second target electrode is turned off. That is, both the first switch S1 and the second switch S2 are turned on, and both the third switch S3 and the fourth switch S4 are turned off. The energy storage element 221 is charged to the driving voltage. In the second timing sequence, the connection between the energy storage element 221 and the first target electrode and the second target electrode is turned on, and the connection between the energy storage element 221 and the driving terminal is turned off. That is, both the third switch S3 and the fourth switch S4 are turned on, and both the first switch S1 and the second switch S2 are turned off. The energy storage element 221 outputs an excitation signal to the driving coil.

[0116] The driving voltage can be set by technicians according to their needs. The driving voltage can range from 1V to 30V, meaning it can be any value between 1V and 30V. For example, the driving voltage can be 1V, 3V, 5V, 10V, 12V, 20V, 25V, 28V, or 30V.

[0117] The energy storage element 221 can be a third capacitor, and the capacitance value of the third capacitor can range from 50pF to 47uF, that is, the capacitance value of the third capacitor can be any value within 50pF to 47uF. For example, the capacitance value of the third capacitor can be 50pF, 100pF, 1000pF, 1uF, 5uF, 10uF, 20uF, or 47uF, etc. When the capacitance value of the third capacitor is less than 100pF, for example, the capacitance value of the third capacitor is within 50pF to 100pF, the third capacitor is integrated inside the touch chip 200; when the capacitance value of the third capacitor is greater than or equal to 100pF, the third capacitor can be a discrete capacitor located outside the touch chip 200.

[0118] For example, during the driving time period, the driving voltage waveform (i.e., the voltage waveform of the excitation signal) of the driving coil (the first coil in this embodiment) can be as shown in Figure 18, the driving current waveform (i.e., the current waveform of the excitation signal) of the driving coil can be as shown in Figure 19, and the waveform of the electrode corresponding to the driving coil (i.e., the waveform of the electrode receiving the excitation signal) can be as shown in Figure 20.

[0119] Specifically, the touch driving device 220 also includes a processing module 224. During the i-th driving time period, the i-th first coil is connected to the energy storage element to receive the driving signal, and all second coils (i.e., sensing coils) receive the signal simultaneously. The processing module 224 can obtain the coordinates of the electromagnetic pen in the second coil direction (i.e., the second direction) based on the sensing signals received by all second coils. After scanning all first coils, the processing module 224 can obtain the coordinates of the electromagnetic pen in the first coil direction (i.e., the first direction) based on the sensing signals received by all second coils in each driving time period. Combining the two, the touch coordinates of the electromagnetic pen can be finally obtained. Where i = 1, 2, ..., n, i is an integer.

[0120] For example, in the alternating drive mode, the timing of each touch detection can be as shown in Figure 21. In this embodiment, if the duration of the drive time period is t1, then the total duration required for each touch detection is n×t1.

[0121] Specifically, the odd-even drive mode refers to the driving method in which the odd-numbered secondary coils and even-numbered secondary coils among the n first coils and n second coils take turns connecting with the energy storage element 221 to receive drive signals, thereby realizing touch coordinate detection.

[0122] In the case of an odd-even drive mode, in some optional embodiments, the number of energy storage elements 221 is a specified number, and the touch drive device also includes a second time-division multiplexer, through which n first coils and n second coils are respectively connected to a specified number of energy storage elements 221. The number of first switches S1, second switches S2, third switches S3, and fourth switches S4 connected to the energy storage elements 221 is also a specified number.

[0123] The second time-division multiplexer is used to connect the odd-numbered or even-numbered secondary coils of the n first coils to the energy storage element 221, or the second time-division multiplexer is used to connect the odd-numbered or even-numbered secondary coils of the n second coils to the energy storage element 221, and the driving coil is the coil of the n first coils or n second coils that is connected to the energy storage element 221.

[0124] The specified quantity is n / 2 rounded up, where n is an integer greater than or equal to 2. For example, n = 9, meaning multiple first electrodes form 9 first coils, in which case the specified quantity is 5, meaning the number of energy storage elements 221 can be 5. As another example, n = 8, meaning multiple first electrodes form 8 first coils, in which case the specified quantity is also 4, meaning the number of energy storage elements 221 can be 4.

[0125] For example, taking n=7 as an example to illustrate the odd-even drive mode, as shown in Figure 22, in the first (i.e., the first drive time period), the first coil (the coil formed by TX0 and TX1), the third coil (the coil formed by TX2 and TX3), the fifth coil (the coil formed by TX4 and TX5), and the seventh coil (the coil formed by TX6 and TX7) are all connected to the energy storage element 221. At this time, the first target electrode mentioned above can be TX0, TX2, TX4, and TX6, and the second target electrode can be TX1, TX3, TX5, and TX7. As shown in Figure 23, in the second (i.e., the second drive time period), the second coil (the coil formed by TX1 and TX2), the fourth coil (the coil formed by TX3 and TX7), and the fifth coil (the coil formed by TX4 and TX5) are connected to the energy storage element 221. The first coil (formed by TX5 and TX6) and the sixth first coil are both connected to the energy storage element 221. As shown in Figure 24, in the third driving time period, the first second coil (formed by RX0 and RX1), the third second coil (formed by RX2 and RX3), the fifth second coil (formed by RX4 and RX5), and the seventh second coil (formed by RX6 and RX7) are all connected to the energy storage element 221. As shown in Figure 25, in the fourth driving time period, the second second coil (formed by RX1 and RX2), the fourth second coil (formed by RX3 and RX4), and the sixth second coil (formed by RX5 and RX6) are all connected to the energy storage element 221. At this time, the driving coils are, in sequence, the odd-numbered coils among the n first coils, the even-numbered coils among the n first coils, the odd-numbered coils among the n second coils, and the even-numbered coils among the n second coils.

[0126] It should be noted that this invention does not limit the driving order of the odd-numbered and even-numbered secondary coils among the n first coils and n second coils. For example, the driving coils can also be, in sequence, the even-numbered secondary coils among the n first coils, the odd-numbered secondary coils among the n first coils, the even-numbered secondary coils among the n second coils, and the odd-numbered secondary coils among the n second coils. Specifically, when the even-numbered secondary coils and the odd-numbered secondary coils among the n first coils receive the driving signal, all second coils detect the induced signal; when the even-numbered secondary coils and the odd-numbered secondary coils among the n second coils receive the driving signal, all first coils detect the induced signal.

[0127] This embodiment does not limit the specific structure of the second time-division multiplexer, as long as the odd-numbered and even-numbered secondary coils of the n first coils and n second coils are sequentially connected to the energy storage element 221. For example, the structure of the second time-division multiplexer can be the same as that of the first time-division multiplexer 223.

[0128] In the case of an odd-even drive mode, in some alternative embodiments, the number of energy storage elements 221 can be 2n, with n first coils and n second coils corresponding one-to-one to the 2n energy storage elements 221. The drive coil is either an even-numbered or odd-numbered coil among the n first coils, or an even-numbered or odd-numbered coil among the n second coils. The number of first switches S1, second switches S2, third switches S3, and fourth switches S4 connected to the energy storage elements 221 is also specified.

[0129] Specifically, when the driving mode is the odd-even driving mode, the number of driving time periods required to complete the touch detection is 4, that is, each touch scan includes 4 driving time periods, and the driving time periods include the first timing sequence and the second timing sequence that are set alternately.

[0130] In the first timing sequence, the connection between the energy storage element 221 and the driving terminal is turned on, and the connection between the energy storage element 221 and the first target electrode and the second target electrode is turned off. That is, both the first switch S1 and the second switch S2 are turned on, and both the third switch S3 and the fourth switch S4 are turned off. The energy storage element 221 is charged to the driving voltage. In the second timing sequence, the connection between the energy storage element 221 and the first target electrode and the second target electrode is turned on, and the connection between the energy storage element 221 and the driving terminal is turned off. That is, both the third switch S3 and the fourth switch S4 are turned on, and both the first switch S1 and the second switch S2 are turned off. The energy storage element 221 outputs an excitation signal to the driving coil.

[0131] For example, during the driving time period, the driving voltage waveform of the driving coil (in this embodiment, the first coil or the second coil) can also be as shown in Figure 18, the driving current waveform of the driving coil can also be as shown in Figure 19, and the waveform of the electrode corresponding to the driving coil can also be as shown in Figure 20.

[0132] Specifically, the touch driving device 220 also includes a processing module 224. When the first coil is used as the driving coil and the second coil is used as the sensing coil, the processing module 224 determines the coordinates of the electromagnetic pen in the direction of the second coil based on the sensing signals received by all the sensing coils in the corresponding two driving time periods. When the second coil is used as the driving coil and the first coil is used as the sensing coil, the processing module 224 determines the coordinates of the electromagnetic pen in the direction of the first coil based on the sensing signals received by all the sensing coils in the corresponding two driving time periods. Combining the two, the touch coordinates of the electromagnetic pen can be finally obtained.

[0133] For example, in the odd-even driving mode, the timing of each touch detection can be as shown in Figure 26. In this embodiment, if the duration of the driving time period is t1, then the total duration required for each touch detection is 4×t1.

[0134] In this embodiment, the odd-even driving mode is used to realize touch detection, which can significantly reduce the scanning time of touch detection and thus improve the efficiency of touch detection.

[0135] For example, the energy storage element 221 is a capacitor. The charging and discharging curves of the capacitor during the driving time period can be shown in Figure 27. Both the capacitor charging curve and the capacitor discharging curve can be exponential curves. The charging and discharging time constant can be determined by the following formula (1): τ=R1×C1 (1)

[0136] Where τ represents the charging and discharging time constant, R1 represents the on-resistance of the switch on the path, and C1 represents the capacitance value of capacitor C1. The smaller R and C1 are, the steeper the edge, and the shorter the time required for the voltage to reach steady state (driving voltage).

[0137] Specifically, the circuit model of the coupling between the driving coil and the inductor coil in the electromagnetic pen can be shown in Figure 28. The driving coil can be equivalent to the first inductor N1, the first coil resistor R1 and the first coil parallel capacitor C3, and the electromagnetic pen can be equivalent to the second inductor N2, the second coil resistor R2 and the first coil parallel capacitor C4.

[0138] The quality factor Q of the coil can be determined by the following formula (2):

[0139] Where Q represents the quality factor, the larger the Q value, the lower the energy loss; R represents the resistance value of the first coil resistor R1; L represents the inductance value of the first inductor N1; and C represents the capacitance value of the first coil parallel capacitor C3.

[0140] The resonant frequency of the coil can be determined by the following formula (3):

[0141] Where f represents the resonant frequency of the coil.

[0142] Specifically, when a driving signal (such as excitation current) is present in the driving coil, a changing magnetic field is generated around the driving coil. The inductor coil inside the electromagnetic pen generates an induced current in the changing magnetic field, and the sensing coil (the coil on the touch screen that is interleaved with the driving coil) also generates an induced current (i.e., a sensing signal) in the changing magnetic field.

[0143] For example, in order to improve signal quantity and ensure detection accuracy, the resonant frequency of the drive coil is between 80% and 120% of the resonant frequency of the inductor coil in the electromagnetic pen. That is, the resonant frequency of the drive coil can be any value between 80% and 120% of the resonant frequency of the inductor coil. For example, the resonant frequency of the drive coil can be 80% of the resonant frequency of the inductor coil, the resonant frequency of the inductor coil, or 120% of the resonant frequency of the inductor coil, etc.

[0144] For example, the resonant frequency can be in the range of 50kHz to 500kHz, the coding frequency of the second coil and the first coil can also be in the range of 50kHz to 500kHz, R≤500Ω, L can be in the range of 1nH to 1mH, and C can be in the range of 10pf to 1nf, in order to improve the Q value of the coil and enhance the sensitivity of the touch.

[0145] Specifically, the resonant frequency can be any value between 50kHz and 500kHz, for example, the resonant frequency can be 50kHz, 100kHz, 200kHz, 300kHz, 350kHz or 500kHz, etc.; the coding frequency of the second coil and the first coil can be any value between 50kHz and 500kHz, for example, the coding frequency of the second coil and the first coil can be 50kHz, 100kHz, 120kHz, 200kHz, 350kHz or 500kHz, etc.; L can be any value between 1nH and 1mH, for example, L can be 1nH, 10nH, 50nH, 0.5mH or 1mH, etc.; C can be any value between 10pf and 1nf, for example, C can be 10pf, 50pf, 100pf, 0.1nf, 0.5nf or 1nf, etc.

[0146] For example, the touch driving device 220 also includes a processing module 224, which is used to determine touch coordinates based on the sensing signal. The following describes two ways in which the processing module 224 determines touch coordinates based on the sensing signal with reference to the accompanying drawings.

[0147] In some optional embodiments, there is a stop driving time period between two adjacent driving time periods, as shown in FIG29. After each driving coil coding, the coding is stopped for a preset time before coding is performed again. During the stop driving time period, since the current of the inductor coil in the electromagnetic pen does not change abruptly, the resonant current between the parallel capacitor of the coil and the electromagnetic pen is still maintained for a period of time. The induced magnetic field generated by the electromagnetic pen will in turn affect the induced current in the sensing coil. The processing module 224 can determine the touch coordinates of the electromagnetic pen according to the changes in the sensing signals detected by multiple sensing coils during the stop driving time period.

[0148] In this configuration, when the driving coil is the first coil, the sensing coil consists of n second coils; when the driving coil is the second coil, the sensing coil consists of n first coils.

[0149] For example, in Figure 29, during touch detection, the driving coil has a non-coding phase. During the coding phase, the current of the driving coil ranges from 1mA to 100mA, and during the non-coding phase, the current of the driving coil is 0mA. The current of the inductor coil in the electromagnetic pen ranges from 0.1mA to 50mA. When the driving coil is in the coding phase, if the electromagnetic pen is close to the touch screen, the signal received by the sensing coil is the superposition of a first signal and a second signal. The first signal is determined by coupling through the driving coil, and the current of the first signal ranges from 1mA to 50mA. The second signal is determined by coupling through the inductor coil in the electromagnetic pen, and the current of the second signal ranges from 0.01mA to 25mA. When the driving coil is in the non-coding phase, if the electromagnetic pen is close to the touch screen, the signal received by the sensing coil is the second signal.

[0150] In this embodiment, the touch coordinates can be directly determined by detecting the sensing signal when coding stops, without the need for additional circuitry, thus reducing the cost of touch detection.

[0151] In some other embodiments, there is no stop driving time period between two adjacent driving time periods, as shown in FIG30. Each time a touch is detected, the driving coil is always in a driven state. At this time, as shown in FIG30, there is a difference between the sensing signal detected by the sensing coil when the electromagnetic pen is close to the display screen and the sensing signal detected by the sensing coil when the electromagnetic pen is not close to the display screen. The processing module 143 can determine the touch coordinates of the electromagnetic pen based on the reference signal and the sensing signals detected by multiple sensing coils during the driving time period.

[0152] In this configuration, when the driving coil is the first coil, the sensing coil consists of n second coils; when the driving coil is the second coil, the sensing coil consists of n first coils.

[0153] For example, in Figure 30, during touch detection, the drive coil is always in the coding stage, and the current of the drive coil ranges from 1mA to 100mA, while the current of the inductor coil in the electromagnetic pen ranges from 0.1mA to 50mA. When the drive coil is in the coding stage, if the electromagnetic pen is close to the touch screen, the signal received by the sensing coil is the superposition of the first and second signals; if the electromagnetic pen is not close to the touch screen, the signal received by the sensing coil is the first signal.

[0154] Specifically, in this embodiment, when no electromagnetic pen is near the display screen (or touch screen), the average value of the sensing signals detected by all sensing coils can be the base signal; when an electromagnetic pen is near the display screen, the sensing signal detected by the sensing coils is the base signal plus the electromagnetic pen signal (i.e., the superposition of the first signal and the second signal). The processing module 224 can determine the touch coordinates of the electromagnetic pen by using the difference between the base signal and the sensing signals detected by multiple sensing coils during the driving time period. When all differences are 0, it can be considered that no electromagnetic pen is near the display screen; when all differences are not 0, it can be considered that an electromagnetic pen is near the display screen, and the position of the sensing coil corresponding to the non-zero difference is the touch coordinate.

[0155] In this embodiment, the sensing signal can be detected while the driving coil receives the driving signal, without waiting, which can improve the efficiency of touch detection.

[0156] In this embodiment, as shown in FIG31, the analog front-end circuit 210 in the touch chip 200 and the electrodes forming the sensing coil are connected via a transimpedance amplifier 230 (TIA), an accumulation module 240, an averaging module 250, a self-capacitance mode switching module 260, and an averaging analog front-end circuit 270. The cooperation of the transimpedance amplifier 230, the accumulation module 240, the averaging module 250, the self-capacitance mode switching module 260, and the averaging analog front-end circuit 270 enables the processing module 224 to determine the reference signal and the difference between the reference signal and the sensing signals detected by the multiple sensing coils during the driving time period.

[0157] Specifically, as shown in Figure 31, the cross-group amplifier 230 includes a first amplifier A1, a third resistor R3, a fourth resistor R4, and a fifth capacitor C5.

[0158] The first terminal of the third resistor R3 is connected to different second electrodes, such as RX0, RX1, or RX. nThe second terminal of the third resistor R3 is connected to the inverting input terminal of the first amplifier A1. The first terminal of the fourth resistor R4 is connected to the inverting input terminal of the first amplifier A1, and the second terminal of the fourth resistor R4 is connected to the output terminal of the first amplifier A1. The first terminal of the fifth capacitor C5 is connected to the inverting input terminal of the first amplifier A1, and the second terminal of the fifth capacitor C5 is connected to the output terminal of the first amplifier A1. The non-inverting input terminal of the first amplifier A1 is connected to the averaging submodule 123, and multiple non-inverting input terminals of the first amplifier A1 are connected to the output terminal of the averaging submodule 123. The output terminal of the first amplifier A1 is connected to the accumulator module 240, and multiple output terminals of the first amplifier A1 are respectively connected to multiple input terminals of the accumulator module 240. The first amplifier A1 transmits the output signal to the accumulator module 240 through its output terminal, and the averaging submodule 250 transmits the error signal to the non-inverting input terminal of the first amplifier A1.

[0159] The accumulator module 240 includes multiple fifth resistors R5. The first end of each fifth resistor R5 is connected to the output of the first amplifier A1, and the second end of each fifth resistor R5 is connected to the input of the averaging amplifier module 250. Each fifth resistor R5 can be matched to a different first amplifier A1. The first ends of different fifth resistors R5 are connected to the outputs of different first amplifiers A1, and the second ends of different fifth resistors R5 are connected to the same input of the averaging amplifier module 250.

[0160] The averaging module 250 includes an amplifier 251 and a loop stability compensation unit 252. When the resistance values ​​of each fifth resistor R5 are the same, the ratio of the resistance value of the fifth resistor R5 to the resistance value of the loop stability compensation unit 252 is equal to the number of fifth resistors R5. Each cross-group amplifier 230, together with the accumulation module 240, the self-capacitance mode switching module 260, and the averaging module 250, can form a feedback loop. The loop stability compensation unit 252 can compensate for the stability of the feedback loop through a combination of resistors and capacitors, making the phase margin greater than 45° and the gain margin greater than 10dB, thereby ensuring that the feedback loop will not oscillate and improving the stability of the processing module in processing touch signals.

[0161] The self-capacitance mode switching module 260 transmits a reference voltage signal to the averaging amplifier module 250. The reference voltage signal serves as a bias to make the error signal output by the averaging amplifier module 250 a positive signal. Subsequently, based on the error signal, the cross-group amplifier 230 can amplify and process the input signal (which can be positive or negative) from the sensing coil into a positive output signal, so as to facilitate processing by subsequent circuits and meet the requirements of the single power supply design of the touch chip.

[0162] The self-capacitance mode switching module 260 includes a first DC voltage source V1, a first coding unit T1, a sixth switch S6, and a seventh switch S7. The output terminal of the self-capacitance mode switching module 260 is connected to the first terminal of the sixth switch S6 and the first terminal of the seventh switch S7, respectively. The second terminal of the sixth switch S6 is connected to the first DC voltage source V1, and the second terminal of the seventh switch S7 is connected to the first coding unit T1.

[0163] In mutual capacitance mode, the sixth switch S6 is closed and the seventh switch S7 is open, and the first DC voltage source V1 transmits a DC voltage (DC level) to the output of the self-mutual capacitance mode switching module 260 as a reference voltage signal. In self-capacitance mode, the sixth switch S6 is open and the seventh switch S7 is closed, and the first coding unit T1 transmits a self-capacitance coding signal to the output of the self-mutual capacitance mode switching module 260 as a reference voltage signal.

[0164] In this embodiment, the cross-group amplifier 230 can output an output signal based on the input signal from the sensing coil. The feedback module formed by the accumulation module 240, the averaging module 250, and the self-capacitance mode switching module 260 can generate an error signal based on the output signal of each cross-group amplifier 230. The error signal can indicate the average intensity of the interference signal coupled to the sensing coil. After the error signal is fed back to the cross-group amplifier 230, the cross-group amplifier 230 can suppress the interference signal in the input signal based on the error signal, thereby reducing the interference signal in the output signal. This makes the effective touch signal in the output signal have a larger dynamic range, thereby improving the accuracy of touch recognition when the subsequent circuit (processing module 224) performs touch recognition based on the output signal.

[0165] Since the loop stability compensation unit 252 can compensate for the stability of the feedback loop through a combination of resistors and capacitors, the loop stability compensation unit 252 can take many different forms, thus giving the averaging amplifier module 250 multiple circuit structures. Figures 32 to 35 show four circuit structures of the averaging amplifier module 250. The possible circuit structures of the averaging amplifier module 250 are described below.

[0166] As shown in Figure 32, the averaging module 250 includes a second amplifier A2, a sixth capacitor C6, a seventh capacitor C7, a sixth resistor R6, and a seventh resistor R7. The non-inverting input of the second amplifier A2 is connected to the self-capacitance mode switching module 260, and the inverting input of the second amplifier A2 is connected to the first terminal of the seventh resistor R7. The second terminal of the seventh resistor R7 is connected to the second terminal of each fifth resistor R5. The output of the second amplifier A2 is connected to the non-inverting input of each first amplifier A1. The first terminal of the sixth resistor R6 is connected to the output of the second amplifier A2, and the second terminal of the sixth resistor R6 is connected to the first terminal of the seventh capacitor C7. The second terminal of the seventh capacitor C7 is connected to the inverting input of the second amplifier A2. The first terminal of the sixth capacitor C6 is connected to the output of the second amplifier A2, and the second terminal of the sixth capacitor C6 is connected to the inverting input of the second amplifier A2.

[0167] As shown in Figure 33, the average amplification module 250 includes a third amplifier A3, an eighth capacitor C8, a ninth capacitor C9, a tenth capacitor C10, an eighth resistor R8, a ninth resistor R9, and a tenth resistor R10. The non-inverting input of the third amplifier A3 is connected to the self-capacitance mode switching module 260, and the inverting input of the third amplifier A3 is connected to the first terminal of the tenth resistor R10. The second terminal of the tenth resistor R10 is connected to the second terminal of each of the fifth resistors R5. The output of the third amplifier A3 is connected to the non-inverting input of each of the first amplifiers A1. The first terminal of the eighth resistor R8 is connected to the output of the third amplifier A3, and the second terminal of the eighth resistor R8 is connected to the first terminal of the ninth capacitor C9. The second terminal of the ninth capacitor C9 is connected to the first terminal of the eighth capacitor C8, the second terminal of the eighth capacitor C8 is connected to the first terminal of the ninth resistor R9, and the second terminal of the ninth resistor R9 is connected to the second terminal of the tenth resistor R10. The first terminal of the tenth capacitor C10 is connected to the output terminal of the third amplifier A3, and the second terminal of the tenth capacitor C10 is connected to the second terminal of the ninth capacitor C9 and the inverting input terminal of the third amplifier A3.

[0168] As shown in Figure 34, the average amplification module 250 includes a fourth amplifier A4, an eleventh capacitor C11, a twelfth capacitor C12, an eleventh resistor R11, a twelfth resistor R12, and a thirteenth resistor R13. The non-inverting input of the fourth amplifier A4 is connected to the self-capacitance mode switching module 260, and the inverting input of the fourth amplifier A4 is connected to the first terminal of the thirteenth resistor R13. The second terminal of the thirteenth resistor R13 is connected to the second terminal of each of the fifth resistors R5. The output of the fourth amplifier A4 is connected to the non-inverting input of each of the first amplifiers A1. The first terminal of the eleventh resistor R11 is connected to the output of the fourth amplifier A4. The second terminal of the eleventh resistor R11 is connected to the first terminal of the twelfth capacitor C12. The second terminal of the twelfth capacitor C12 is connected to both the first terminal of the eleventh capacitor C11 and the inverting input of the fourth amplifier A4. The second terminal of the eleventh capacitor C11 is connected to the first terminal of the twelfth resistor R12, and the second terminal of the twelfth resistor R12 is connected to the second terminal of the thirteenth resistor R13.

[0169] As shown in Figure 35, the averaging module 250 includes a fifth amplifier A5, a thirteenth capacitor C13, a fourteenth resistor R14, and a fifteenth resistor R15. The non-inverting input of the fifth amplifier A5 is connected to the self-capacitance mode switching module 260, and the inverting input of the fifth amplifier A5 is connected to the first terminal of the fifteenth resistor R15. The second terminal of the fifteenth resistor R15 is connected to the second terminal of each of the fifth resistors R5. The first terminal of the fourteenth resistor R14 is connected to the output terminal of the fifth amplifier A5, and the second terminal of the fourteenth resistor R14 is connected to the first terminal of the thirteenth capacitor C13. The second terminal of the thirteenth capacitor C13 is connected to the inverting input of the fifth amplifier A5.

[0170] For example, as shown in FIG31, the analog front-end circuit 210 includes a filter 211, a sample and hold (S / H) module 212, an analog-to-digital converter buffer (ADCBUF) 213, and an analog-to-digital converter buffer (ADC) 214.

[0171] The filter 211 is used to remove noise, suppress unwanted frequency bands, or perform anti-aliasing processing to ensure high-quality signals in the subsequent analog-to-digital conversion process. The sample-and-hold module 212 samples the analog signal before analog-to-digital conversion and keeps the sampled value unchanged for a period of time to avoid conversion errors caused by signal fluctuations. The buffer 213 of the analog-to-digital converter isolates the input of the ADC from the preceding circuit, reducing the influence of the preceding circuit on the ADC input and maintaining signal integrity. The analog-to-digital converter 214 converts the continuously changing analog signal into a discrete digital signal. The mechanism of the mean analog front-end circuit 270 is the same as that of the analog front-end circuit 210, and will not be described again here.

[0172] The present invention also provides a driving method for a touch driving device, which can be used in the above-mentioned touch driving device. Figure 36 is a schematic flowchart of a driving method for a touch driving device according to an embodiment of the present invention. As shown in Figure 36, the method includes the following steps:

[0173] Step S3601: In the first time sequence of the i-th driving time period, control the connection between the energy storage element and the driving end to be turned on, and control the connection between the energy storage element and the first target electrode and the second target electrode to be turned off, so that the energy storage element is charged to the driving voltage.

[0174] The driving time period includes alternating first and second timing sequences, i = 1, 2, ..., R, R ≥ 2, and i and R are integers.

[0175] For example, the first and second switches can be controlled to be turned on to connect the energy storage element to the drive end, and the third and fourth switches can be controlled to be turned off to disconnect the energy storage element from the first and second target electrodes.

[0176] In some optional implementations, prior to step S3401, the method further includes: determining a driving mode, wherein the driving mode includes a round-robin driving mode and an odd-even driving mode, wherein in the round-robin driving mode, R = n, and in the odd-even driving mode, R = 4.

[0177] In step S3402, during the second timing sequence of the i-th driving time period, the connection between the energy storage element and the first target electrode and the second target electrode is turned on, and the connection between the energy storage element and the driving end is turned off, so that the energy storage element outputs an excitation signal to the driving coil.

[0178] Specifically, the third and fourth switches are controlled to be turned on, so that the connection between the energy storage element and the first and second target electrodes is made, and the first and second switches are controlled to be turned off, so that the connection between the energy storage element and the driving end is turned off.

[0179] The driving method of the touch driving device provided in this embodiment can avoid the driving signal being split and interfering with each other in multiple coils by introducing an energy storage capacitor to send a driving signal to the driving coil, thereby effectively improving the signal quantity and the signal consistency between the edge and the center.

[0180] The present invention also provides a touch controller, including the touch driving device provided in any of the above embodiments, wherein the touch controller can be a touch chip.

[0181] The present invention also provides a display device, as shown in Figures 37 and 38. The display device includes a substrate, a thin film transistor (TFT) layer 372, a light-emitting unit 373, a cathode plate 374, a light-emitting unit encapsulation layer 375, a touch screen 376, a polarizer 377, and a cover plate stacked from bottom to top. The touch screen 376 is connected to a touch driving device.

[0182] It should be understood that, based on the various embodiments provided by the present invention, the process method for processing or manufacturing the display device can be selected from the feasible methods based on the present invention. For example, under the concept of the present invention, structures such as a substrate, a thin film transistor (TFT) layer 372, a light-emitting unit 373, a cathode plate 374, a light-emitting unit encapsulation layer 375, a touch screen 376, a polarizer 377, and a cover plate can be prepared. The specific manufacturing process will not be described in detail in this specification.

[0183] In some alternative implementations, the display screen can be an organic light-emitting diode (OLED) flexible screen as shown in Figure 37. In this case, the substrate can be a polyimide (PI) substrate 3711, and the cover plate can be a flexible cover plate 3781. The display screen can also be an OLED rigid screen as shown in Figure 37. In this case, the substrate can be a glass substrate 3712, and the cover plate can be a glass cover plate 3782.

[0184] In this embodiment, for example, the switching between capacitive touch detection and electromagnetic pen coordinate detection can be achieved by switching the TFT layer. The specific capacitive touch detection process and the switching process of electromagnetic pen coordinate detection can be configured accordingly based on the present invention, and will not be elaborated here.

[0185] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0186] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0187] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0188] In the description of this specification, the references to terms such as "this embodiment," "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0189] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0190] The above description does not provide detailed explanations of the technical aspects of each layer's patterning, etching, etc. However, those skilled in the art should understand that various technical means can be used to form layers and regions of the desired shape. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above. Additionally, although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination.

[0191] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the present invention.

Claims

1. A touch-driven device, characterized in that, include: An energy storage element is used to connect to a driving end and to connect to a first target electrode and a second target electrode; wherein the first target electrode and the second target electrode are used to form a driving coil, the first target electrode and the second target electrode are electrodes among a plurality of first electrodes on a touch screen, or the first target electrode and the second target electrode are electrodes among a plurality of second electrodes on the touch screen, the first electrode is a transmitting electrode, and the second electrode is a receiving electrode; The driving module includes the driving terminal.

2. The touch driving device according to claim 1, characterized in that, The touch driving device also includes a first switch, a second switch, a third switch, and a fourth switch; One end of the first switch is connected to the driving end, and the other end of the first switch is connected to the first end of the energy storage element. One end of the second switch is connected to the second end of the energy storage element, and the other end of the second switch is grounded. One end of the third switch is connected to the first end of the energy storage element, and the other end of the third switch is used to connect to the first target electrode. One end of the fourth switch is connected to the second end of the energy storage element, and the other end of the fourth switch is used to connect to the second target electrode.

3. The touch driving device according to claim 2, characterized in that, The first switch, the second switch, the third switch, the fourth switch, and the driving module are integrated on the touch chip, and the energy storage element is a first capacitor located outside the touch chip.

4. The touch driving device according to claim 3, characterized in that, The capacitance value of the first capacitor is greater than or equal to 100pF.

5. The touch driving device according to claim 2, characterized in that, The first switch, the second switch, the third switch, the fourth switch, the driving module, and the energy storage element are integrated on the touch chip, and the energy storage element is a second capacitor located inside the touch chip.

6. The touch driving device according to claim 5, characterized in that, The capacitance value of the second capacitor is less than 100pF.

7. The touch driving device according to claim 2, characterized in that, The drive module also includes a control unit; The control unit is used to control the first switch, the second switch, the third switch, and the fourth switch to be turned on or off, so that the driving end charges the energy storage element and the energy storage element outputs an excitation signal to the driving coil.

8. The touch driving device according to any one of claims 1 to 7, characterized in that, The energy storage element is one, the plurality of first electrodes form n first coils, and the touch driving device further includes a first time-division multiplexer; The n first coils are connected to the energy storage element through the first time-division multiplexer. The first time-division multiplexer is used to connect the n first coils to the energy storage element in sequence. The driving coil is the coil among the n first coils that is connected to the energy storage element. Here, n is an integer greater than or equal to 2.

9. The touch driving device according to claim 8, characterized in that, Each touch scan includes n driving time periods, which include alternating first and second timing sequences. During the first timing sequence, the connection between the energy storage element and the driving terminal is turned on, and the connection between the energy storage element and the first and second target electrodes is turned off, and the energy storage element is charged to the driving voltage. During the second timing sequence, the connection between the energy storage element and the first and second target electrodes is turned on, and the connection between the energy storage element and the driving terminal is turned off, and the energy storage element outputs an excitation signal to the driving coil.

10. The touch driving device according to any one of claims 1 to 7, characterized in that, The plurality of first electrodes form n first coils, the plurality of second electrodes form n second coils, the number of energy storage elements is a specified number, and the touch driving device further includes a second time-division multiplexer; The n first coils and the n second coils are respectively connected to a specified number of energy storage elements through the second time-division multiplexer. The second time-division multiplexer is used to connect the odd-numbered or even-numbered secondary coils of the n first coils to the energy storage elements, or the second time-division multiplexer is used to connect the odd-numbered or even-numbered secondary coils of the n second coils to the energy storage elements. The driving coil is the coil of the n first coils or the n second coils that is connected to the energy storage elements. Wherein, the specified quantity is n / 2 rounded up, where n is an integer greater than or equal to 2.

11. The touch driving device according to claim 10, characterized in that, Each touch scan includes four driving time periods, which include an alternately set first timing sequence and a second timing sequence; During the first timing sequence, the connection between the energy storage element and the driving terminal is turned on, the connection between the energy storage element and the first target electrode and the second target electrode is turned off, and the energy storage element is charged to the driving voltage. During the second timing sequence, the connection between the energy storage element and the first target electrode and the second target electrode is turned on, the connection between the energy storage element and the driving end is turned off, and the energy storage element outputs an excitation signal to the driving coil.

12. The touch driving device according to any one of claims 1 to 7, characterized in that, The resonant frequency of the drive coil is between 80% and 120% of the resonant frequency of the inductor coil in the electromagnetic pen.

13. The touch driving device according to claim 1, 2, or 7, characterized in that, The energy storage element is a third capacitor, and the capacitance value of the third capacitor ranges from 50pF to 47Uf.

14. The touch driving device according to any one of claims 1 to 7, characterized in that, The touch driving device also includes a processing module, which is used to determine the touch coordinates of the electromagnetic pen based on the sensing signals detected by multiple sensing coils during the stop driving time period. Wherein, the plurality of first electrodes form n first coils, the plurality of second electrodes form n second coils, when the driving coil is a first coil, the sensing coil is the n second coils, and when the driving coil is a second coil, the sensing coil is the n first coils, where n is an integer greater than or equal to 2.

15. The touch driving device according to any one of claims 1 to 3, characterized in that, The touch driving device also includes a processing module, which is used to determine the touch coordinates of the electromagnetic pen based on a reference signal and sensing signals detected by multiple sensing coils during the driving time period. Wherein, the plurality of first electrodes form n first coils, the plurality of second electrodes form n second coils, when the driving coil is a first coil, the sensing coil is the n second coils, and when the driving coil is a second coil, the sensing coil is the n first coils, where n is an integer greater than or equal to 2.

16. A driving method for a touch-sensitive driving device, characterized in that, The touch chip includes an energy storage element and a driving module. The energy storage element is used to connect to a driving terminal and to connect to a first target electrode and a second target electrode. The driving module includes the driving terminal. The first target electrode and the second target electrode are used to form a driving coil. The first target electrode and the second target electrode are electrodes among a plurality of first electrodes on the touch screen, or the first target electrode and the second target electrode are electrodes among a plurality of second electrodes on the touch screen. The first electrode is a transmitting electrode, and the second electrode is a receiving electrode. The method includes: In the first timing sequence of the i-th driving time period, the connection between the energy storage element and the driving terminal is turned on, and the connection between the energy storage element and the first target electrode and the second target electrode is turned off, so that the energy storage element is charged to the driving voltage. The driving time period includes an alternately set first timing sequence and a second timing sequence, i = 1, 2, ..., R, R ≥ 2, and i and R are integers. During the second timing period of the i-th driving time period, the connection between the energy storage element and the first target electrode and the second target electrode is turned on, and the connection between the energy storage element and the driving end is turned off, so that the energy storage element outputs an excitation signal to the driving coil.

17. The method according to claim 16, characterized in that, Before the connection between the energy storage element and the driving end is turned on during the first time sequence of the i-th driving time period, the method further includes: determining a driving mode, wherein the driving mode includes a rotating driving mode and an odd-even driving mode, wherein in the rotating driving mode, R = n, and in the odd-even driving mode, R = 4.

18. A touch controller, characterized in that, Includes the touch driving device as described in any one of claims 1 to 15.

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