Touch-control detection method, touch-control chip, touch-control detection system, and electronic device

Abstract

A touch-control detection method, a touch-control chip (100), a touch-control detection system (10), and an electronic device. The touch-control detection method comprises: applying a driving signal to a touch-control sensor (200), wherein the driving signal comprises N first signal segments of equal length, the difference between initial phases of two adjacent first signal segments among the N first signal segments is a preset phase value, and the preset phase value is greater than 0 and less than or equal to π, N being an integer greater than or equal to 2; acquiring, from the touch-control sensor (200), a touch-control sensing signal corresponding to the driving signal, wherein the touch-control sensing signal comprises N second signal segments corresponding to the N first signal segments on a one-to-one basis; demodulating the N second signal segments by using a demodulation signal having a phase synchronized with the driving signal, so as to obtain N pieces of demodulated data corresponding to the N second signal segments; and performing accumulation processing on the N pieces of demodulated data to obtain a demodulation result of the touch-control sensing signal, so as to determine a touch-control detection result.

Description

Touch detection method, touch chip, touch detection system and electronic equipment Technical Field

[0001] The embodiments of the present application relate to the field of touch technology, and in particular to a touch detection method, a touch chip, a touch detection system, and an electronic device. Background Art

[0002] Capacitive touch technology provides a convenient and efficient human-computer interaction experience, and is therefore widely used in electronic devices such as laptops, tablets, smartphones, and smart speakers.

[0003] Existing capacitive touch devices use either self-capacitance detection or mutual capacitance detection for touch detection. Taking mutual capacitance detection as an example, during touch detection, the capacitive touch device applies a drive signal to the touch panel's drive electrodes, then obtains a sensing signal corresponding to the excitation signal from the touch panel's sensing electrodes. Based on this sensing signal, it determines whether an external object is touching or approaching the touch panel.

[0004] However, capacitive touch devices face a complex environment of internal and external interference during use, including interference from chargers, displays, and other internal modules. This can cause these noise interferences to be coupled into the sensing signals captured by the capacitive touch devices. This noise interference includes in-band co-channel interference, which significantly impacts touch technology performance, reducing the sensitivity and accuracy of touch detection.

[0005] Summary of the Invention

[0006] In view of this, embodiments of the present application provide a touch detection solution to at least partially solve the above-mentioned problem.

[0007] According to a first aspect of an embodiment of the present application, a touch detection method is provided, including:

[0008] Applying a drive signal to the touch sensor, the drive signal comprising N first signal segments of equal length, wherein a difference in initial phases between two adjacent first signal segments of the N first signal segments is a preset phase value, the preset phase value is greater than 0 and less than or equal to π, and N is a positive integer greater than or equal to a quotient of 2π and the preset phase value;

[0009] acquiring, from the touch sensor, a touch sensing signal corresponding to the driving signal, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments;

[0010] Demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal to obtain N demodulated data corresponding to the N second signal segments;

[0011] Accumulation processing is performed on the N demodulated data to obtain a demodulation result of the touch sensing signal, which is used to determine a touch detection result.

[0012] As mentioned in the background technology section, capacitive touch devices are often affected by co-channel interference caused by internal and external environments during use. Therefore, in response to applying a drive signal to the touch sensor, the touch sensing signal obtained from the touch sensor contains a co-channel noise signal at the same frequency as the drive signal. Specifically, each of the N second signal segments included in the touch sensing signal contains both a valid signal that is phase-synchronized with the corresponding first signal segment and a co-channel noise signal at the same frequency as the drive signal. Because a demodulated signal that is phase-synchronized with the drive signal is used when demodulating the N second signal segments, that is, the demodulated signal includes N demodulated signal segments that are phase-synchronized with the N first signal segments, the valid signal in each second signal segment is phase-synchronized with the corresponding demodulated signal segment. This ensures that the energy of the valid signal remains unchanged when the corresponding N demodulated data obtained by demodulating the N second signal segments are accumulated. At the same time, because the co-channel noise signal is generally considered continuous during the touch detection process, the initial phase of the co-channel noise signal in two adjacent second signal segments is the same. The difference in initial phase between two adjacent demodulated signal segments in the N demodulated signal segments is a preset phase value, such that for two adjacent second signal segments, the difference between the initial phase of the co-frequency noise signal in the preceding second signal segment and the corresponding demodulated signal segment and the initial phase of the co-frequency noise signal in the succeeding second signal segment is the preset phase value, and the preset phase value is greater than 0 and less than or equal to π. This is equivalent to phase modulating the co-frequency noise signal. Thereafter, when the corresponding N demodulated data obtained by demodulating the N second signal segments are accumulated and processed, the co-frequency noise energy in the N second signal segments is at least partially offset, thereby reducing the co-frequency noise energy in the touch sensing signal, improving the signal-to-noise ratio in the presence of co-frequency interference, and thus improving the sensitivity and accuracy of touch detection.

[0013] According to a second aspect of an embodiment of the present application, a touch detection method is provided, including:

[0014] Applying a drive signal to the touch sensor, the drive signal comprising N first signal segments of equal length, wherein two adjacent first signal segments of the N first signal segments have the same initial phase, a second time interval exists between the two adjacent first signal segments, and a phase difference corresponding to the second time interval modulo 2π is a preset phase value, wherein the preset phase value is greater than 0 and less than or equal to π, and N is an integer greater than or equal to 2;

[0015] acquiring, from the touch sensor, a touch sensing signal corresponding to the driving signal, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments;

[0016] Demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal to obtain N demodulated data corresponding to the N second signal segments;

[0017] Accumulation processing is performed on the N demodulated data to obtain a demodulation result of the touch sensing signal, which is used to determine a touch detection result.

[0018] Similar to the first aspect, in response to applying a driving signal to the touch sensor, a touch sensing signal obtained from the touch sensor includes N second signal segments, each of which includes both a valid signal phase-synchronized with the corresponding first signal segment and a co-frequency noise signal co-frequency with the driving signal. Because a demodulation signal phase-synchronized with the driving signal is used when demodulating the N second signal segments, the valid signal in each second signal segment is phase-synchronized with the corresponding demodulated signal segment. This ensures that the energy of the valid signal remains unchanged when the corresponding N demodulated data obtained by demodulating the N second signal segments are accumulated. Furthermore, because the co-frequency noise signal is generally assumed to be continuous during the touch detection process, a second time interval exists between adjacent two second signal segments in the N second signal segments that correspond one-to-one to the N first signal segments, resulting in an initial phase difference between the noise signals in the two adjacent second signal segments corresponding to the second time interval. The modulo 2π of the phase difference corresponding to the second time interval is a preset phase value. The initial phases of two adjacent demodulated signal segments in the N demodulated signal segments are the same, so that for two adjacent second signal segments, the difference between the initial phase of the co-frequency noise signal in the first second signal segment and the corresponding demodulated signal segment and the initial phase of the co-frequency noise signal in the second second signal segment and the corresponding demodulated signal segment is the phase difference corresponding to the second time interval. The modulo result of the phase difference corresponding to the second time interval and 2π is a preset phase value, and the preset phase value is greater than 0 and less than or equal to π. This is equivalent to phase modulation of the co-frequency noise signal. Thereafter, when the corresponding N demodulated data obtained by demodulating the N second signal segments are accumulated and processed, the co-frequency noise energy in the N second signal segments is at least partially offset, thereby significantly reducing the co-frequency noise energy in the touch sensing signal, improving the signal-to-noise ratio in the event of co-frequency interference, and thus improving the sensitivity and accuracy of touch detection.

[0019] According to a third aspect of an embodiment of the present application, a touch detection method is provided, including:

[0020] Applying a drive signal to the touch sensor, the drive signal comprising N first signal segments of equal length, initial phases of two adjacent first signal segments of the N first signal segments having a first phase difference, a third time interval existing between the two adjacent first signal segments, a sum of the phase difference corresponding to the third time interval and the first phase difference modulo 2π being a preset phase value, the preset phase value being greater than 0 and less than or equal to π, where N is an integer greater than or equal to 2;

[0021] acquiring, from the touch sensor, a touch sensing signal corresponding to the driving signal, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments;

[0022] Demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal, and generating N demodulated data corresponding to the N second signal segments;

[0023] Accumulation processing is performed on the N demodulated data to obtain a demodulation result of the touch sensing signal, which is used to determine a touch detection result.

[0024] Similar to the first aspect, in response to applying a drive signal to the touch sensor, each of the N second signal segments included in the touch sensing signal obtained from the touch sensor includes both a valid signal that is phase-synchronized with the corresponding first signal segment and a co-frequency noise signal that is co-frequency with the drive signal. Because a demodulation signal that is phase-synchronized with the drive signal is used when demodulating the N second signal segments, the valid signal in each of the N second signal segments is phase-synchronized with the corresponding demodulated signal segment. This ensures that the energy of the valid signal remains unchanged when the N demodulated data obtained by demodulating the N second signal segments are accumulated. At the same time, since the co-channel noise signal is generally considered continuous during the touch detection process, a third time interval exists between the initial phase difference between two adjacent demodulated signal segments in the N demodulated signals that are phase-synchronized with the N first signal segments, and between two adjacent second signal segments in the N second signal segments that correspond one-to-one to the N first signal segments. This ensures that, for two adjacent second signal segments, the modulo 2π of the difference between the initial phase difference between the co-channel noise signal in the preceding second signal segment and the corresponding demodulated signal segment and the initial phase difference between the co-channel noise signal in the following second signal segment is a preset phase value, and the preset phase value is greater than 0 and less than or equal to π. This is equivalent to phase modulating the co-channel noise signal. Subsequently, when the corresponding N demodulated data obtained by demodulating the N second signal segments are accumulated and processed, the co-channel noise energy in the N second signal segments is at least partially offset, thereby significantly reducing the co-channel noise energy in the touch sensing signal, improving the signal-to-noise ratio in the presence of co-channel interference, and thus improving the sensitivity and accuracy of touch detection.

[0025] According to a fourth aspect of an embodiment of the present application, a touch control chip is provided, comprising: a driving circuit, a receiving circuit, and a demodulation circuit. The driving circuit is configured to apply a driving signal to a touch sensor, wherein the driving signal comprises N first signal segments of equal length, wherein the difference in initial phase between two adjacent first signal segments in the N first signal segments is a preset phase value, wherein the preset phase value is greater than 0 and less than or equal to π, and N is an integer greater than or equal to 2. The receiving circuit is configured to obtain a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal comprises N second signal segments corresponding one-to-one to the N first signal segments. The demodulation circuit is configured to demodulate the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal to obtain N demodulated data corresponding to the N second signal segments, and to accumulate the N demodulated data to obtain a demodulation result of the touch sensing signal for use in determining a touch detection result.

[0026] According to a fifth aspect of the embodiments of the present application, a touch control chip is provided, comprising: a driving circuit, a receiving circuit, and a demodulation circuit. The driving circuit is configured to apply a driving signal to a touch sensor, wherein the driving signal comprises N first signal segments of equal length, wherein two adjacent first signal segments of the N first signal segments have the same initial phase, a second time interval exists between the two adjacent first signal segments, and the modulo result of the phase difference corresponding to the second time interval and 2π is a preset phase value, wherein the preset phase value is greater than 0 and less than or equal to π, and N is an integer greater than or equal to 2. The receiving circuit is configured to obtain a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal comprises N second signal segments corresponding one-to-one to the N first signal segments. The demodulation circuit is configured to demodulate the N second signal segments using a demodulation signal synchronized with the phase of the driving signal to obtain N demodulated data corresponding to the N second signal segments, and to accumulate the N demodulated data to obtain a demodulation result of the touch sensing signal for use in determining a touch detection result.

[0027] According to a sixth aspect of an embodiment of the present application, a touch control chip is provided, comprising: a driving circuit, a receiving circuit, and a demodulation circuit. The driving circuit is configured to apply a driving signal to a touch sensor, wherein the driving signal comprises N first signal segments of equal length, wherein the initial phases of two adjacent first signal segments in the N first signal segments have a first phase difference, and a third time interval exists between the two adjacent first signal segments. The sum of the phase difference corresponding to the third time interval and the first phase difference modulo 2π is a preset phase value, wherein the preset phase value is greater than 0 and less than or equal to π, and N is an integer greater than or equal to 2. The receiving circuit is configured to obtain a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal comprises N second signal segments corresponding one-to-one to the N first signal segments. The demodulation circuit is configured to demodulate the N second signal segments using a demodulation signal synchronized with the phase of the driving signal to obtain N demodulated data corresponding to the N second signal segments, and to accumulate the N demodulated data to obtain a demodulation result of the touch sensing signal for use in determining a touch detection result.

[0028] According to a seventh aspect of the embodiments of the present application, a touch detection system is provided, comprising a touch sensor and a touch chip as provided in any one of the fourth to sixth aspects.

[0029] According to an eighth aspect of the embodiments of the present application, an electronic device, a touch screen and a touch detection system as provided in the seventh aspect are provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0031] FIG1 is a schematic diagram of an exemplary system applicable to the touch detection method according to an embodiment of the present application;

[0032] FIG2 shows a connection diagram of a self-capacitance detection circuit according to an embodiment of the present application;

[0033] FIG3 shows a connection diagram of a mutual capacitance detection circuit according to an embodiment of the present application;

[0034] FIG4 is a block diagram showing the working principle of a demodulation circuit according to an embodiment of the present application;

[0035] FIG5 is a schematic diagram showing a signal waveform in a continuous driving mode within a frame in the related art;

[0036] FIG6 shows a partial enlarged view of the driving signal in FIG5 ;

[0037] FIG7 is a schematic diagram showing a signal waveform under an intra-frame coding driving mode in the related art;

[0038] FIG8 is a schematic diagram showing a flow chart of a touch detection method provided according to an embodiment of the present application;

[0039] FIG9 shows a noise frequency response curve when the touch detection method provided according to an embodiment of the present application is adopted;

[0040] FIG10 shows a noise frequency response curve when a conventional touch detection method is used;

[0041] FIG11 shows an exemplary timing diagram of a self-capacitive detection method provided according to an embodiment of the present application;

[0042] FIG12 shows an exemplary timing diagram of a self-capacitive detection method provided according to an embodiment of the present application;

[0043] FIG13 shows an exemplary timing diagram of a multi-channel mutual capacitance detection method provided according to an embodiment of the present application;

[0044] FIG14 shows an exemplary timing diagram of another multi-channel mutual capacitance detection method provided according to an embodiment of the present application;

[0045] FIG15 shows an exemplary waveform diagram after multiplication in a quadrature demodulation process according to an embodiment of the present application;

[0046] FIG16 shows an exemplary waveform diagram after accumulation of the orthogonal demodulation process provided in an embodiment of the present application;

[0047] FIG17 is a schematic diagram showing a flow chart of a touch detection method provided according to an embodiment of the present application;

[0048] FIG18 shows an exemplary timing diagram of another self-capacitive detection method provided according to an embodiment of the present application;

[0049] FIG19 shows an exemplary timing diagram of a mutual capacitance multi-channel detection method provided according to an embodiment of the present application;

[0050] FIG20 is a schematic diagram showing a flow chart of a touch detection method provided according to an embodiment of the present application;

[0051] FIG21 shows an exemplary timing diagram of another self-capacitive detection method provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0052] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field should fall within the scope of protection of the embodiments of the present application.

[0053] The specific implementation of the embodiment of the present application is further explained below in conjunction with the accompanying drawings of the embodiment of the present application.

[0054] Figure 1 is a schematic diagram of a touch detection system applicable to the touch detection method according to an embodiment of the present application. As shown in Figure 1 , the touch detection system 10 includes a touch sensor 200 and a touch chip 100 , wherein the touch chip 100 is connected to the touch sensor 200 .

[0055] The touch sensor 200 may be a self-capacitive touch sensor. The self-capacitive touch sensor may include multiple independent detection electrodes. The multiple independent detection electrodes may be arranged in an array. Each detection electrode is coupled to ground to form a touch self-capacitance.

[0056] The touch sensor 200 may also be a mutual capacitance touch sensor. A mutual capacitance touch sensor may include a plurality of drive electrodes and a plurality of sensing electrodes arranged crosswise, and each drive electrode is coupled with each sensing electrode to form a touch mutual capacitance. The touch sensor 200 may also be a touch sensor configured to operate in both self-capacitance detection mode and mutual capacitance mode. FIG1 shows an example of such a touch sensor. As shown in FIG1 , the touch sensor includes a plurality of drive electrodes Tx extending in parallel along a first direction (e.g., horizontal direction or X direction) and a plurality of sensing electrodes Rx extending parallel to each other along a second direction (e.g., vertical direction or Y direction). The first direction and the second direction are perpendicular to each other.

[0057] The touch control chip 100 includes a control circuit 103, a drive circuit 101, a receiving circuit 102, a demodulation circuit 104, and a digital processing circuit 105. The drive circuit 101 and the receiving circuit 102 are connected to the multiple drive electrodes TX and the multiple sense electrodes RX in the touch sensor 200 via a switch circuit 106. The digital processing circuit 105 is used to control the connection mode of the switch circuit 106. The control circuit 103 is used to control the drive circuit 101 and the demodulation circuit to generate drive signals and demodulation signals. For example, the control circuit 103 can control the timing, phase, frequency, duration, etc. of the generated drive signals and demodulation signals.

[0058] In the example of FIG. 1 , the touch control chip 100 may use a self-capacitance detection method or a mutual-capacitance detection method to determine a touch detection result, such as detecting touch coordinates and the presence / absence of a touch.

[0059] The self-capacitance detection method identifies the touch or proximity of an external object by detecting the capacitance change of the drive electrode / sense electrode relative to the ground. As shown in Figure 2, the digital processing circuit 105 controls the switch circuit 106 to connect the drive circuit 101 and the receiving circuit 102 to the same drive electrode TX and / or the same sensing electrode RX, thereby making the touch sensor work in the self-capacitance detection mode. In the self-capacitance detection mode, the drive electrode and the sensing electrode are not distinguished. For ease of description, in the self-capacitance detection mode, the drive electrode and the sensing electrode are collectively referred to as the detection electrode. The drive circuit 101 is used to apply the drive signal to the detection electrode, and the receiving circuit 102 is used to sense the detection electrode to obtain a touch sensing signal (hereinafter also referred to as a received signal) corresponding to the drive signal. The touch sensing signal changes with the touch or proximity of an object such as a finger or a pen. The self-capacitance detection method detects the presence / absence of touch coordinates and touch based on the change of the sensing signal.

[0060] The mutual capacitance detection method identifies the touch or proximity of an external object by detecting the change in capacitance between the drive electrode and the coupled sensing electrode. As shown in Figure 3, the digital processing circuit 105 controls the switch circuit 106 to connect the drive circuit 101 to the drive electrode and the receiving circuit 102 to the sensing electrode, thereby enabling the touch sensor to operate in the mutual capacitance detection mode. In the mutual capacitance detection mode, the drive circuit 101 is used to apply a drive signal to the drive electrode, and the receiving circuit 102 is used to receive a touch sensing signal from the sensing electrode coupled to the drive electrode. The touch sensing signal changes with the touch or proximity of an object such as a finger or pen. The mutual capacitance detection method detects touch coordinates and the presence / absence of touch based on the touch sensing signal.

[0061] Depending on the driving mode, the mutual capacitance detection method includes single-channel mutual capacitance detection and multi-channel mutual capacitance detection. For single-channel mutual capacitance detection, a driving signal is applied to each of the multiple driving electrodes in turn during the touch detection period. For single-channel mutual capacitance detection, an intra-frame continuous driving mode is generally used, which is also applicable to the self-capacitance detection method. For the multi-channel mutual capacitance detection method, a driving signal is applied to M driving electrodes of the multiple driving electrodes at the same time during the touch detection period, and M driving signals are applied to each driving electrode during the touch detection period, where M is an integer greater than or equal to 2. For multi-channel mutual capacitance detection, an intra-frame coding driving mode is generally used. The following will refer to examples to explain in detail the single-channel mutual capacitance detection and the corresponding intra-frame continuous driving mode, as well as the multi-channel mutual capacitance detection and the corresponding intra-frame continuous driving mode, which will not be repeated here.

[0062] In the self-capacitance detection method and the mutual capacitance detection method, after the receiving circuit 102 receives the touch sensing signal, the touch sensing signal is provided to the demodulation circuit 104. The demodulation circuit 104 is an orthogonal demodulation circuit 104. The orthogonal demodulation circuit 104 generates an orthogonal demodulation signal, which includes an in-phase demodulation signal and a quadrature-phase demodulation signal. The implementation principle of the orthogonal demodulation circuit 104 is as follows: the touch sensing signal enters a two-way orthogonal multiplier, one of which is multiplied with the in-phase demodulation signal to obtain an in-phase signal, and the other is multiplied with the quadrature-phase demodulation signal to obtain a quadrature-phase signal. Thereafter, the in-phase signal and the quadrature-phase signal are further processed by filtering and other means to obtain a demodulation result of the touch sensing signal, which is used to determine the touch detection result. Figure 4 shows a schematic diagram of the principle of a demodulation circuit 104 provided in an embodiment of the present application. As shown in Figure 4 , after the touch sensing signal enters the demodulation circuit 104, it is multiplied by the in-phase demodulation signal cos(ωt) through multiplier I_CH, and by the quadrature-phase demodulation signal -sin(ωt) through multiplier Q_CH. The results of the two multiplications are then filtered and processed to produce the demodulated touch sensing signal.

[0063] It should be understood that the in-phase demodulation signal cos(ωt) and the quadrature-phase demodulation signal -sin(ωt) in FIG4 are merely examples. In other embodiments, the in-phase demodulation signal and the quadrature-phase demodulation signal may take other forms as long as the phase difference is π / 2 radians.

[0064] In the embodiment shown in FIG1 , the demodulation circuit 104 transmits the demodulation result of the touch sensing signal to the digital processing circuit 105 . The digital processing circuit 105 processes the demodulation result of the touch sensing signal to obtain touch data, and sends the touch data to the main controller, which determines the touch detection result.

[0065] It should be understood that the embodiment shown in Figure 1 is only an example. In other embodiments, the process of processing the demodulation result of the touch sensing signal to obtain touch data can be completed by the demodulation circuit 104, or can be completed by other circuits arranged between the demodulation circuit 104 and the digital processing circuit 105. This embodiment does not limit this.

[0066] As shown in FIG1 , the touch control chip 100 may further include a filtering circuit and an ADC circuit (not shown). The filtering circuit is configured to filter the touch sensing signal to obtain a filtered touch sensing signal. The ADC circuit is configured to perform analog-to-digital conversion on the filtered touch sensing signal to obtain a converted touch sensing signal, and then transmit the converted touch sensing signal to the demodulation circuit 104 for demodulation. It should be understood that the filtering circuit and the ADC circuit may be separate circuits provided independently of the receiving circuit 102 and the demodulation circuit 104, or may be integrated with the receiving circuit 102 or the demodulation circuit, and this embodiment does not limit this.

[0067] Based on the exemplary touch detection system 1 shown in FIG1 , conventional touch detection methods use two driving modes to drive the touch sensor 200. One mode is an intra-frame continuous driving mode, and the other is an intra-frame coding driving mode. The intra-frame continuous driving mode refers to continuously applying a driving signal to each driving electrode during the touch detection cycle. The driving signal lasts for a period of time to ensure that the driving signal has the desired bandwidth. The bandwidth of the driving signal is inversely proportional to the duration of the driving signal. The bandwidth of the driving signal can generally be from several hundred microseconds to more than ten milliseconds. The specific bandwidth is related to the window function used to prevent spectrum leakage. The intra-frame coding driving mode refers to applying multiple phase-encoded driving signals to each driving electrode during the touch detection cycle. The intra-frame continuous driving mode is applicable to self-capacitance detection and single-channel mutual capacitance detection. The intra-frame coding driving form is applicable to multi-channel mutual capacitance detection.

[0068] As mentioned above, capacitive touch devices face very complex internal and external interference environments during use, such as interference from the charger, display screen, and interference coupled by other internal modules. This causes noise interference to be coupled into the touch sensing signal obtained by the capacitive touch device. These noise interferences include in-band co-channel interference, which has a significant impact on the performance of touch technology, that is, co-channel noise signals with the same frequency as the driving signal. However, traditional capacitive touch detection methods, whether they adopt intra-frame continuous driving or intra-frame coding driving, are more sensitive to these co-channel noise signals, resulting in a low signal-to-noise ratio for the touch detection system when there is co-channel interference, which in turn results in low sensitivity and accuracy of touch detection.

[0069] To facilitate understanding, two examples are provided below for detailed explanation. In the first example, based on the exemplary touch detection system shown in FIG1 , a conventional self-capacitance detection method using an intra-frame continuous drive mode is used as an example for explanation. In the second example, also based on the exemplary touch detection system shown in FIG1 , a conventional mutual capacitance detection method using an intra-frame coded drive mode is used as an example for explanation.

[0070] First example

[0071] In the self-capacitance detection mode, as shown in FIG2 , the driving circuit 101 and the receiving circuit 102 are connected to the same driving electrode or sensing electrode (hereinafter referred to as the detection electrode). FIG5 and FIG6 show the driving signal applied by the driving circuit 101 to the detection electrode in the self-capacitance detection mode. As shown in FIG5 and FIG6 , the driving signal includes multiple signal waveforms, and one signal waveform corresponds to one signal period T. The driving frequency of the driving signal refers to the driving frequency of the signal waveform in the driving signal. Correspondingly, the driving period of the driving signal refers to the driving period T of the signal waveform in the driving signal. In this example, as shown in FIG6 , the square wave of the driving signal should be understood to be only an example. In other examples, the driving signal can be a sine wave, a triangle wave, etc., and this embodiment does not limit this. In addition, in this example, in order to ensure the signal bandwidth, the duration of the driving signal is Tcw1=M*T, where M is an integer greater than 1. As those skilled in the art should know, in the absence of noise influence, when the driving signal is applied to the detection electrode, the touch sensing signal obtained from the detection electrode (i.e., the touch sensing signal corresponding to the driving signal) is synchronized with the phase of the driving signal. Phase synchronization means that the phases of the two signals are the same at every moment or there is always a fixed phase difference. In the following, for the sake of convenience, the touch sensing signal obtained without the influence of noise is called a valid signal.

[0072] Since the capacitive touch detection system has to face a very complex internal and external interference environment in actual use, when the driving circuit 101 applies a driving signal to the detection electrode, the touch sensing signal obtained from the detection electrode includes not only the above-mentioned effective signal, but also a noise signal. These noise signals enter the touch detection system within the duration Tw1 of the driving signal. Since the duration Tcw1 is relatively short, it is generally believed that the phase of the noise signal entering the system during this time period is continuous and there is no phase mutation. In this example, the driving signal is represented as cos(ωt), where ω is the angular frequency of the driving signal, ω=2*π*f. As mentioned above, since the phase of the driving signal is synchronized with the corresponding effective signal, in the example shown in Figure 5, the driving signal is used to represent the corresponding effective signal. The same-frequency noise signal with the same frequency as the driving signal is represented as sin(ωt). In addition, the orthogonal demodulation signals used in the demodulation circuit are represented as cos(ωt) and -sin(ωt), respectively. It should be understood that FIG5 is only an example. In other examples, the driving signal and the same-frequency noise signal may both be represented as cos(ωt) or sin(ωt), or as other signal waveforms with a certain frequency and amplitude.

[0073] After the drive circuit 101 applies the drive signal cos(ωt) shown in Figure 5 to the detection electrode, the touch sensing signal obtained by the receiving circuit 102 from the detection electrode includes the effective signal cos(ωt) and the co-frequency noise signal sin(ωt). Therefore, the signal entering the demodulation circuit includes the effective signal cos(ωt) and the co-frequency noise signal sin(ωt).

[0074] For the same-frequency noise signal sin(ωt), after entering the demodulation circuit, the same-frequency noise signal is multiplied by the in-phase demodulation signal cos(ωt) and the quadrature-phase demodulation signal -sin(ωt) respectively to obtain the in-phase signal and quadrature-phase signal corresponding to the same-frequency noise signal. The in-phase signal and quadrature-phase signal corresponding to the same-frequency noise signal are expressed as follows:

[0075] In the duration Tcw1, the in-phase signal and the quadrature-phase signal corresponding to the same-frequency noise signal are respectively integrated or accumulated, and the high-frequency components are filtered to obtain the in-phase DC signal and the quadrature-phase DC signal corresponding to the same-frequency noise signal. The in-phase DC signal and the quadrature-phase DC signal corresponding to the same-frequency noise signal are respectively: I noise =0

[0076] It can be obtained that the modulus and phase angle of the same-frequency noise signal after orthogonal demodulation are:

[0077] From the above formula, we can know that the modulus of the same-frequency noise signal after orthogonal demodulation is This shows that the traditional capacitive touch detection method using intra-frame continuous driving is more sensitive to co-frequency noise, has poor anti-interference ability, and has low sensitivity and accuracy in touch detection.

[0078] Second example

[0079] In the mutual capacitance detection mode, as shown in FIG3 , the driving circuit 101 is connected to the driving electrode, and the receiving circuit 102 is connected to the sensing electrode. In this example, based on the exemplary touch detection system described in FIG1 , the four driving electrodes Tx are driven simultaneously, that is, the four channels are driven simultaneously. Referring to FIG1 , the four driving electrodes TX (i.e., the four channels Tx) are Tx1 to Tx4, and the four sensing electrodes RX (i.e., the four channels Tx) arranged crosswise with the four driving electrodes are RX1 to RX4. As shown in FIG7 , four phase-encoded driving signals are applied to each driving electrode Tx. For ease of description, these four phase-encoded driving signals are referred to as four-segment phase encoding in the following text, each segment of encoding is denoted as code, and the initial phase of the four-segment phase encoding is represented by Φ1. As shown in FIG7 , the initial phase Φ1 of code1 is 0 degrees, the initial phase Φ1 of code2 is 0 degrees, the initial phase Φ1 of code3 is 0 degrees, and the initial phase Φ1 of code4 is 180 degrees. The relative starting phases of the four phase codes are indicated by a "+" or "-" sign, with the "+" and "-" codes representing opposite starting phases. In this example, the four phase codes for driving electrode Tx1 are Code1(+), Code2(+), Code3(+), and Code4(-). The duration of each code is Tcw1, and the interval between two adjacent codes is Td. Figure 7 only schematically illustrates the four phase codes applied to Tx1. The phase codes for other Txs are shown in the following table:

[0080] Table 1

[0081] In this example, the driving signals applied to the four driving electrodes Tx1 to Tx4 are represented by a matrix A. The matrix A is:

[0082] Where Aij in matrix A represents the i-th drive signal applied to the j-th drive electrode. 1 indicates that the relative starting phases of the drive signals are the same, corresponding to the "+" in Table 1, and -1 indicates that the relative starting phases of the drive signals are opposite, corresponding to the "-" in Table 1.

[0083] In this example, the mutual capacitances formed between the four driving electrodes Tx1 to Tx4 and the four cross-connected sensing electrodes Rx1 to Rx4 are represented by a matrix C. The matrix C is:

[0084] Wherein, Cij represents the touch capacitance formed between the i-th driving electrode and the j-th sensing electrode.

[0085] In this example, the demodulation results corresponding to the touch sensing signals received from the four sensing electrodes Rx1 to Rx4 during the touch sensing period can be represented by a matrix R, which is:

[0086] Here, Rij represents the demodulation result of the touch sensing signal corresponding to the i-th driving signal obtained from the j-th sensing electrode.

[0087] R=AC, by solving C=A -1 R, the change of mutual capacitance C can be obtained, that is, the touch data can be obtained. It can be seen that in the multi-channel mutual capacitance detection method, although the driving signal is applied to the four driving electrodes at the same time, the touch sensing signal obtained from the sensing electrode (correspondingly, the demodulation result corresponding to the touch sensing signal) is caused by the driving signal applied to the four driving electrodes. However, for each driving electrode, for each driving signal applied to the driving electrode (that is, each code), the sensing electrodes Rx1 to Rx4 have an independent demodulation result. Each of the four phase-encoded driving signals applied to each driving electrode (each code) can be regarded as a driving signal in the first example. Therefore, for each code, the demodulated modulus of the same-frequency noise in the touch sensing signal obtained from the sensing electrode is This shows that the traditional capacitive touch detection method using intra-frame coding drive is also sensitive to co-frequency noise, has poor anti-interference ability, and has low sensitivity and accuracy in touch detection.

[0088] In view of the above problems, the present application provides a touch detection method, which is mainly based on the phase continuity of the same-frequency noise signal within the touch detection cycle. By designing the phase of the demodulated signal to change synchronously with the phase of the drive signal over time and / or designing the interval time between the demodulated signal and the drive signal to change the phase difference between the same-frequency noise and the demodulated signal entering the capacitive touch detection system in different time periods, the phase modulation of the noise signal is realized, and then the noise energy is changed while ensuring that the signal energy remains unchanged, thereby improving the signal-to-noise ratio of the capacitive touch detection system, thereby improving the sensitivity and accuracy of touch detection.

[0089] The specific implementation of the embodiment of the present application is further explained below in conjunction with the accompanying drawings of the embodiment of the present application.

[0090] FIG8 is a flow chart showing a touch detection method according to an embodiment of the present application. The touch detection method is performed by the touch control chip 10 shown in FIG1 . As shown in FIG8 , the method includes:

[0091] S801: Apply a driving signal to the touch sensor, where the driving signal includes N first signal segments of equal length, where the difference in initial phase between two adjacent first signal segments in the N first signal segments is a preset phase value, where the preset phase value is a value greater than 0 and less than or equal to π, and N is an integer greater than or equal to 2.

[0092] S802: Acquire a touch sensing signal corresponding to the driving signal from the touch sensor, where the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments;

[0093] S803, demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal to obtain N demodulated data corresponding to the N second signal segments;

[0094] S804 , performing accumulation processing on the N demodulated data to obtain a demodulation result of the touch sensing signal for use in determining a touch detection result.

[0095] S801 and S802 are respectively executed by the driving circuit 101 and the receiving circuit 102 in the touch chip 10 shown in Figure 1. For a touch sensor configured to operate in a self-capacitance detection mode, applying a driving signal to the touch sensor may include: the driving circuit 101 applies a driving signal to the detection electrode of the touch sensor. Correspondingly, the receiving circuit 102 obtains a touch sensing signal from the detection electrode to which the driving signal is applied. The touch sensing signal is a self-capacitance coupled signal of the driving signal. In one implementation, the driving circuit may apply the driving signal to each of the multiple detection electrodes of the touch sensor in sequence. In another implementation, the driving circuit may simultaneously apply the driving signal to at least some of the multiple detection electrodes of the touch sensor.

[0096] For a touch sensor configured in mutual capacitance detection mode, applying a drive signal to the touch sensor includes applying the drive signal to a drive electrode of the touch sensor. Accordingly, the receiving circuit 102 may receive a touch sensing signal from a sensing electrode that intersects with the drive signal to which the drive signal is applied. The touch sensing signal is a mutual capacitance coupling signal of the drive signal. Specifically, in one implementation, applying the drive signal to the touch sensor may include: in single-channel mutual capacitance detection mode, the drive circuit 101 simultaneously applying the drive signal to one of a plurality of drive electrodes of the touch sensor. Accordingly, the receiving circuit 102 receives the touch sensing signal from each sensing electrode that intersects with the drive electrode. In one implementation of the present application, applying the drive signal to the touch sensor may include: in multi-channel mutual capacitance detection mode, the drive circuit 101 simultaneously applying the drive signal to M drive electrodes of the plurality of drive electrodes, and applying M drive signals to each of the M drive electrodes, where the M drive signals are phase-encoded drive signals, and M is an integer greater than or equal to 2 and less than or equal to the total number of drive electrodes in the touch sensor. For example, taking four-channel simultaneous driving as an example, driving signals are applied to four driving electrodes Tx at the same time, and four phase-encoded driving signals are applied to each driving electrode TX. The driving signals are sometimes referred to as coded driving signals below.

[0097] In this embodiment, the driving signal has a driving frequency f. The driving frequency of the driving signal is the frequency f of the signal waveform contained in the driving signal. The driving period of the driving signal is the period T of the signal waveform contained in the driving signal, where T=1 / f. The driving signal includes N first signal segments of equal length. The duration of each first signal segment is Tc, and the total duration of the driving signal is Tw1=N*Tc. Each duration contains a signal waveform of k signal periods, that is, Tc=K*T=k / f. The number k can be determined based on the bandwidth of the driving signal. The bandwidth of the driving signal is inversely proportional to the total duration of the driving signal. The bandwidth of the driving signal can generally be from several hundred microseconds to more than ten milliseconds. The specific bandwidth is related to the window function used to prevent spectrum leakage.

[0098] The driving signal includes N first signal segments of equal length, and the difference in initial phase between two adjacent first signal segments in the N first signal segments is a preset phase value, and the preset phase value is a value greater than 0 and less than or equal to π. Specifically, the difference in initial phase between the first first signal segment in the N first signal segments and the jth first signal segment in the N first signal segments is the product of the modulo result of j and P and the preset phase value. That is, the difference in initial phase between the first first signal segment in the N first signal segments and the jth first signal segment in the N first signal segments is Φ j , Φ j =(j mod P)*Φp , where P is the quotient of 2π and the preset phase value, Φ p In response to the driving signal, the touch sensing signal acquired by the receiving circuit includes N second signal segments corresponding to the N first signal segments.

[0099] In an ideal noise-free environment, the touch sensing signal and the driving signal are phase-synchronized, that is, they are the same phase or there is always a fixed phase shift. That is, in an ideal noise-free environment, at the same moment, the waveform phase of the touch sensing signal's signal waveform is the same phase as the waveform phase of the driving signal or there is always a fixed phase shift. Therefore, in an ideal noise-free environment, the second signal segment included in the touch sensing signal is phase-synchronized with the corresponding first signal segment. For ease of description, the second signal segment in the ideal noise-free environment is referred to as a valid signal. Therefore, the difference between the initial phases of the valid signals in two adjacent second signal segments among the N second signal segments is a preset phase value, and the preset phase value is a value greater than 0 and less than or equal to π.

[0100] In practical applications, capacitive touch detection technology is susceptible to interference from internal or external environments, particularly co-frequency noise at the same frequency as the drive signal. Therefore, each of the N second signal segments acquired actually contains both a valid signal that is phase-synchronized with the corresponding first signal segment and a co-frequency noise signal at the same frequency as the drive signal. The co-frequency noise signal coupled into the touch sensing signal is generally considered continuous.

[0101] In S803, the demodulation circuit 104 demodulates the N second signal segments using a demodulation signal that is phase-synchronized with the target drive signal. Therefore, the demodulated signal necessarily includes N demodulation signal segments that are phase-synchronized with the N first signal segments, and the initial phase difference between two adjacent demodulation signal segments is a preset phase value. Therefore, the effective signal in the second signal segment is phase-synchronized with the corresponding demodulation signal. This ensures that when the N second signal segments are demodulated using the corresponding demodulation signal and the N demodulation results corresponding to the N second signal segments are accumulated, the energy of the effective signal is not offset by positive or negative energy, that is, there is no energy loss in the effective signal. Furthermore, because the co-frequency noise signal coupled into the touch sensing signal is generally considered continuous, the initial phase of the co-frequency noise signal is the same for two adjacent second signal segments. The difference in initial phase between two adjacent demodulated signal segments is a preset phase value, such that, for two adjacent second signal segments, the difference between the phase difference between the co-frequency noise signal and the corresponding demodulated signal in the preceding second signal segment and the phase difference between the co-frequency noise signal and the corresponding demodulated signal in the succeeding second signal segment is different from the preset phase value, i.e., the phase difference is the preset phase value. Therefore, when demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the drive signal and accumulating the N demodulation results corresponding to the N second signal segments, there is a positive and negative cancellation of the co-frequency noise energy. The noise energy is at least partially cancelled, thereby reducing the co-frequency noise energy in the touch sensing signal, improving the signal-to-noise ratio in the presence of co-frequency interference, and thus improving the sensitivity and accuracy of touch detection.

[0102] Furthermore, for two adjacent second signal segments, the difference between the phase difference between the co-frequency noise signal in the first second signal segment and the corresponding demodulated signal and the phase difference between the co-frequency noise signal in the second signal segment and the corresponding demodulated signal in the second signal segment is a preset phase value, which is equivalent to performing P-phase modulation on the co-frequency noise signal, where P is equal to the quotient of 2π and the preset phase value. By setting N to be greater than P, the modulation process includes at least one complete modulation cycle, thereby ensuring that co-frequency noise coupled into the touch detection system at any point during the touch detection time is effectively offset, thereby significantly reducing the co-frequency noise energy in the touch sensing signal, improving the signal-to-noise ratio in the presence of co-frequency interference, and thus enhancing the sensitivity and accuracy of touch detection.

[0103] In this embodiment, the size of the preset phase value and the size of N can be selected according to the characteristics of the same-frequency noise signal in the application scenario.

[0104] In one implementation of the present application, N is an integer multiple of the quotient of 2π and a preset phase value, which makes the modulation process include an integer multiple of the modulation period, so that the noise energy in the N second signal segments can be offset to the maximum extent, thereby significantly reducing the co-frequency noise energy in the touch sensing signal, maximizing the signal-to-noise ratio in the case of co-frequency interference, and thereby maximizing the sensitivity and accuracy of touch detection.

[0105] In one implementation of the present application, the preset phase value can be π, π / 2, or π / 4, which is equivalent to performing two-phase modulation, four-phase modulation, and eight-phase modulation on the co-frequency noise signal, respectively. By setting the preset phase value to π, π / 2, or π / 4, the sensitivity and accuracy of touch detection can be improved while reducing the amount of calculation.

[0106] In an implementation of the present application, as shown in FIG11 and FIG13 , any two adjacent first signal segments among the N first signal segments Cyc1 to CycN are continuous in time.

[0107] In another implementation of the present application, as shown in Figures 12 and 14, a first time interval Ts1 exists between any two adjacent first signal segments among the N first signal segments, and the phase difference corresponding to the first time interval is an integer multiple of 2π. The phase difference corresponding to the first time interval is the phase difference that can be generated when a signal having a preset frequency passes through the first time interval. The preset frequency is equal to the drive frequency of the drive signal.

[0108] Specifically, the phase difference corresponding to the first time interval and the second time interval have the following relationship: Φ t1 =2π*Ts1*f, where Φ t1 is the phase difference corresponding to the first time interval, Ts1 is the first time interval, and f is the driving frequency of the driving signal. Since the phase difference corresponding to the first time interval T is an integer multiple of 2π, the first time interval is equal to an integer multiple of the driving period of the driving signal. Since the phase difference corresponding to the first time interval is an integer multiple of 2π, that is, the phase difference generated by the same-frequency noise signal with the same frequency as the driving signal when passing through the first time interval is an integer multiple of 2π, therefore, when demodulating the N second signal segments using a demodulation signal synchronized with the phase of the driving signal, for two adjacent second signal segments, the first time interval does not affect the phase difference between the phase difference between the same-frequency noise signal and the corresponding frequency-modulated signal in the preceding second signal segment and the phase difference between the same-frequency noise signal and the corresponding frequency-modulated signal in the following second signal segment.

[0109] For ease of understanding, the embodiments of the present application are specifically described below in conjunction with Figures 12 and 14 through the third example and the fourth example. The third example and the fourth example are based on the exemplary touch detection system shown in Figure 1, and are described by taking the self-capacitance detection method and the multi-channel mutual capacitance detection method as examples respectively. In the third example and the fourth example, it is assumed that the driving frequency of the driving signal is f, and each driving signal includes N first signal segments of equal length, respectively referred to as cyc1 segment, cyc2 segment, ..., cycN segment. Each first signal segment contains k signal waveforms (k is a positive integer), and the duration of each first signal segment is Tc, and Tc = k / f. The difference in the initial phases of two adjacent first signal segments is π radians, and the time interval between two adjacent first signal segments is Ts1, Ts1 = T, and correspondingly, the phase difference corresponding to the first time interval Ts1 is 2π radians.

[0110] Third example

[0111] As shown in Figure 12, assuming the first first signal segment is cos(ωt), since the initial phase difference between two adjacent first signal segments is π radians, the second first signal segment is cos(ωt+π), the third first signal segment is cos(ωt), and the fourth first signal segment is cos(ωt+π). This cycle repeats until the Nth first signal segment. Accordingly, the orthogonal demodulation signal segments corresponding to the first first signal segment are cos(ωt) and -sin(ωt), respectively. The orthogonal demodulation signal segments corresponding to the second first signal segment (segment cyc2) are cos(ωt+π) and -sin(ωt+π), respectively. The orthogonal demodulation signal segments corresponding to the third first signal segment (segment cyc3) are cos(ωt) and -sin(ωt), respectively. The orthogonal demodulation signal segments corresponding to the fourth first signal segment (segment cyc4) are cos(ωt+π) and -sin(ωt+π). The touch sensing signal corresponding to the drive signal includes N second signal segments. Each second signal segment contains a valid signal and a co-frequency noise signal. The valid signal in each second signal segment is phase-synchronized with the corresponding first signal segment. For simplicity, in Figure 12, the valid signal in the second signal segment is directly represented by the signal waveform of the corresponding first signal segment. During touch detection, the co-frequency noise signal is assumed to be continuous. Since the time interval between second signal segments is 2π radians, the co-frequency noise signal in each second signal segment can be expressed as sin(ωt).

[0112] For the same-frequency noise signal in each second signal segment, specifically:

[0113] For the cyc1 segment, the result of multiplying the co-frequency noise signal and the corresponding orthogonal demodulation signal segment is:

[0114] For the cyc2 segment, the result of multiplying the co-frequency noise signal and the corresponding orthogonal demodulation signal segment is:

[0115] For the cyc1 segment, the I cyc1_mult and Q cyc1_mult By integrating and accumulating, we can obtain the in-phase signal and quadrature-phase signal corresponding to the noise signal in the cyc1 segment: cyc1 =cos(ωt)*sin(ωt)=0

[0116] For the cyc2 segment, the I cyc2_mult and Q cyc2_mult By integrating and accumulating, we can obtain the in-phase signal and quadrature-phase signal corresponding to the noise signal in the cyc2 segment: cyc2 =cos(ωt+π)*sin(ωt)=0

[0117] The principles for other segments are the same and will not be repeated here. The results of orthogonal demodulation are shown in Figures 15 and 16.

[0118] The in-phase signal and quadrature-phase signal corresponding to the noise signal in each cyc segment are accumulated and processed, and the demodulation result corresponding to the same-frequency noise signal in the touch sensing signal is obtained as follows:

[0119] That is, the demodulated values ​​of the same-frequency noise signals in two adjacent second signal segments will have a positive and negative offset effect after being accumulated, thereby suppressing the same-frequency noise.

[0120] For the valid signal in the second signal segment, since it is phase-synchronized with the corresponding demodulated signal segment, as shown in Figures 15 and 16, the demodulated values ​​of each segment are accumulated without any positive or negative offset, resulting in no energy loss. This reduces noise energy while maintaining signal energy, improving the signal-to-noise ratio in the presence of co-channel interference, and thus enhancing the sensitivity and accuracy of touch detection.

[0121] Fourth Example

[0122] Taking four channels of simultaneous driving as an example, as shown in FIG14 , the driving circuit 101 applies four driving signals to each Tx. These four driving signals are phase-encoded using a preset encoding method. The preset encoding method used for phase encoding the four driving signals in this embodiment can refer to the second example.

[0123] Compared to the second example using a traditional multi-channel mutual capacitance detection method, in this example: each drive signal includes N first signal segments of equal length, such as segments cyc1, ..., cycN shown in Figure 14. The initial phase difference between two adjacent first signal segments is π, and the first time interval between two adjacent first signal segments is Ts, where Ts = n / f (in the fourth example, n = 1). The phase difference corresponding to the first time interval Ts is 2π radians.

[0124] In this example, the multiplication, integration, and accumulation process of the quadrature demodulation of each first signal segment within each drive signal can refer to the self-capacitance detection method mentioned in the third example. For the N first signal segments within each drive signal, N corresponding quadrature demodulation values ​​I or Q can be obtained. By accumulating the N corresponding quadrature demodulation values ​​I or Q, a set of independent demodulation values ​​I and Q corresponding to each drive signal is obtained as the demodulation result corresponding to the drive signal.

[0125] Similar to the third example, the demodulated values ​​of the co-frequency noise signals in two adjacent second signal segments within each drive signal are accumulated to achieve a positive-negative cancellation effect. That is, in the demodulated results of the touch sensing signals corresponding to each drive signal, the impact of the co-frequency noise is at least partially eliminated, thereby suppressing the co-frequency noise. As for the valid signal in the second signal segment, since it is phase-synchronized with the corresponding demodulated signal segment, the accumulated demodulated values ​​of each segment do not experience positive-negative cancellation, resulting in no energy loss. This reduces noise energy while ensuring that signal energy remains unchanged, improving the signal-to-noise ratio in the presence of co-frequency interference and thus enhancing the sensitivity and accuracy of touch detection.

[0126] In addition, for the third example and the fourth example, non-co-frequency noise is generated while substantially eliminating the co-frequency noise. The frequency point of the generated non-co-frequency noise is: f n =f±f g

[0127] Where f is the frequency of the driving signal, f n is the frequency point of the non-co-frequency noise generated, fg is the peak noise response frequency interval, and

[0128] Assuming that the frequency of the driving signal f = 205 kHz, the duration Tc of each first signal segment includes a signal waveform of 27 signal cycles (i.e., k = 27), and two adjacent first signal segments are continuous in time, i.e., n = 0, the method provided in the embodiment of the present application can be used to obtain the noise frequency response curve shown in FIG9. Compared with the noise frequency response curve obtained by the conventional touch detection method shown in FIG10, the peak noise frequency point is f n =205KHz±3.8KHz.

[0129] In other words, the peak noise frequency deviates by 3.8 kHz from the drive signal frequency, making it possible to use a bandpass filter to filter out non-co-frequency noise. Furthermore, comparing Figures 9 and 10, it can be seen that the amplitude of the non-co-frequency noise generated by the method provided in this embodiment of the application is reduced from 0.707 to 0.45 compared to the traditional touch detection method. Since the signal energy is the same, the method provided in this embodiment of the application can significantly improve the SNR.

[0130] FIG17 is a flow chart showing a touch detection method according to an embodiment of the present application. The touch detection method is performed by the touch control chip 10 shown in FIG1 . As shown in FIG17 , the method includes:

[0131] S1701. Apply a drive signal to the touch sensor, where the drive signal includes N first signal segments of equal length, where two adjacent first signal segments in the N first signal segments have the same initial phase, where a second time interval exists between the two adjacent first signal segments, and where a phase difference corresponding to the second time interval modulo 2π is a preset phase value, where the preset phase value is greater than 0 and less than or equal to π, and where N is an integer greater than or equal to 2.

[0132] S1702: Acquire a touch sensing signal corresponding to the driving signal from the touch sensor, where the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments;

[0133] S1703: demodulate the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal to obtain N demodulated data corresponding to the N second signal segments;

[0134] S1704 , performing accumulation processing on the N demodulated data to obtain a demodulation result of the touch sensing signal, so as to determine a touch detection result.

[0135] Similar to the embodiment shown in FIG8 , the drive signal in this embodiment has a drive frequency f and a drive period T, where T = 1 / f. The drive signal includes N first signal segments of equal length. Each first signal segment has a duration Tc, and the total duration of the drive signal is Tw1 = N * Tc. Each duration contains a signal waveform of k signal periods, i.e., Tc = K * T = k / f.

[0136] The difference between the embodiment of the present application and the embodiment shown in Figure 8 is that the initial phases of two adjacent first signal segments in the N first signal segments are the same, there is a second time interval between the two adjacent first signal segments, and the phase difference corresponding to the second time interval and the modulo result of 2π are preset phase values, and the preset phase value is greater than 0 and less than or equal to π.

[0137] The phase difference corresponding to the second time interval is the phase difference that may be generated when a signal having a preset frequency passes through the second time interval, and the preset frequency is equal to the driving frequency of the driving signal. Specifically, the phase difference corresponding to the second time interval has the following relationship with the second time interval: Φ t2 =2π*Ts2*f, where Φ t2 is the phase difference corresponding to the second time interval, Ts2 is the second time interval, and f is the driving frequency of the driving signal.

[0138] Similar to the aforementioned embodiment, in response to applying a driving signal to the touch sensor, a touch sensing signal obtained from the touch sensor includes N second signal segments, each of which includes both a valid signal phase-synchronized with the corresponding first signal segment and a co-frequency noise signal co-frequency with the driving signal. Since the co-frequency noise signal is generally considered continuous during the touch detection process, a second time interval exists between two adjacent second signal segments in the N second signal segments corresponding one-to-one to the N first signal segments, such that the initial phases of the noise signals in the two adjacent second signal segments have a phase difference corresponding to the second time interval. Furthermore, the initial phases of two adjacent demodulated signal segments in the N demodulated signal segments are the same, such that for two adjacent second signal segments, the difference between the initial phase difference between the co-frequency noise signal in the preceding second signal segment and the corresponding demodulated signal segment and the initial phase difference between the co-frequency noise signal in the following second signal segment and the corresponding demodulated signal segment is the phase difference corresponding to the second time interval. The modulo result of the phase difference corresponding to the second time interval and 2π is a preset phase value. The preset phase value is greater than 0 and less than or equal to π. This is equivalent to phase modulating the co-frequency noise signal. Therefore, when the N second signal segments are demodulated using a demodulation signal that is phase-synchronized with the drive signal, and the N demodulation results corresponding to the N second signal segments are accumulated, the co-frequency noise energy will experience positive and negative cancellation. The noise energy will be at least partially offset, thereby reducing the co-frequency noise energy in the touch sensing signal.

[0139] At the same time, similar to the aforementioned embodiment, because a demodulation signal synchronized with the drive signal phase is used when demodulating the N second signal segments, the effective signal in each second signal segment is phase-synchronized with the corresponding demodulated signal segment. This ensures that the energy of the effective signal remains unchanged when the N demodulated data corresponding to the demodulation of the N second signal segments are accumulated. The energy of the effective signal remains unchanged, and the energy of co-channel noise is at least partially offset, thereby improving the signal-to-noise ratio in the presence of co-channel interference, thereby enhancing the sensitivity and accuracy of touch detection.

[0140] In one implementation of the present application, N is set to be equal to or greater than the quotient of 2π and a preset phase value, so that at least one complete modulation cycle is included in the modulation process. This ensures that the co-frequency noise coupled to the touch detection system at any time point during the touch detection time can be better offset, thereby significantly reducing the co-frequency noise energy in the touch sensing signal.

[0141] In this embodiment, the size of the preset phase value and the size of N can be selected according to the characteristics of the same-frequency noise signal in the application scenario.

[0142] In one implementation of the present application, N is an integer multiple of the quotient of 2π and a preset phase value, which makes the modulation process include an integer multiple of the modulation period, so that the noise energy in the N second signal segments can be offset to the maximum extent, thereby significantly reducing the co-frequency noise energy in the touch sensing signal, maximizing the signal-to-noise ratio in the case of co-frequency interference, and thereby maximizing the sensitivity and accuracy of touch detection.

[0143] In one implementation of the present application, the preset phase value can be π, π / 2, or π / 4. Correspondingly, the second time interval is (n+1 / 2)*T, (n+1 / 4)*T, or (n+1 / 4)*T, where T is the drive period of the drive signal. This is equivalent to performing two-phase modulation, four-phase modulation, and eight-phase modulation on the same-frequency noise signal, respectively. By setting the preset phase value to π, π / 2, or π / 4, the sensitivity and accuracy of touch detection can be improved while reducing the amount of calculation.

[0144] For ease of understanding, the above process is illustrated below through two examples. In the fifth example and the sixth example, based on the exemplary touch detection system shown in Figure 1, the self-capacitance detection method and the multi-channel mutual capacitance detection are respectively used as examples for illustration. In the fifth example and the sixth example, it is assumed that the driving frequency of the driving signal is f, and the driving signal includes N first signal segments of equal length, each first signal segment contains k signal waveforms (k is a positive integer), the duration of each first signal segment is Tc, and Tc=k / f. The initial phases of two adjacent first signal segments are the same, and the phase difference corresponding to the second time interval Ts2 between two adjacent first signal segments is 3*π radians.

[0145] Fifth Example

[0146] As shown in FIG18 , the initial phases of two adjacent first signal segments in the N first signal segments are the same, which is represented by cos(ωt). The touch sensing signal corresponding to the driving signal includes N second signal segments, the effective signal and the same-frequency noise signal in each second signal segment, and the effective signal in each second signal segment is phase-synchronized with the corresponding first signal segment. For the sake of simplicity, the effective signal in the second signal segment is represented by the signal waveform of the corresponding first signal segment. The phase difference corresponding to the second time interval between two adjacent first signal segments is 3π radians, so the corresponding phase difference between the time interval between two adjacent demodulated signal segments in the N demodulated signal segments is 3π radians. In addition, since the same-frequency noise is considered to be continuous during touch detection, the second time interval makes the initial phase difference of the noise signal in the two adjacent second signal segments 3π radians. Typically, when n=0, the same-frequency noise in the first second signal segment can be expressed as sin(ωt), and the initial phase Φ n1 =0, the same frequency noise in the second signal segment can be expressed as sin(ω*t+π), that is, the initial phase Φ n1 =π, the same frequency noise in the third second signal segment can be expressed as sin(ωt), the initial phase Φ n1 =0, the same-frequency noise in the fourth second signal segment can be expressed as sin(ω*t+π), that is, the initial phase Φ n1 =π, and this cycle repeats until the Nth second signal segment. Hereinafter, the time periods corresponding to the N first signal segments are referred to as cyc1 segment, cyc2 segment, ..., cycN segment, respectively.

[0147] For the same-frequency noise signal in each second signal segment, specifically:

[0148] For the cyc1 segment, the results of multiplying the in-phase demodulation signal cos(ωt) and the quadrature-phase demodulation signal -sin(ωt) by the same-frequency noise signal are:

[0149] For the cyc2 segment, the results of multiplying the co-frequency noise signal with the in-phase demodulation signal cos(ωt) and the quadrature-phase demodulation signal -sin(ωt) are:

[0150] For the cyc1 segment, the I cyc1_mult and Q cyc1_mult Perform integration / accumulation respectively to obtain the in-phase signal and quadrature-phase signal corresponding to the noise signal in the cyc1 segment: cyc1 =cos(ωt)*sin(ωt)=0

[0151] For cyc2, within the duration Tc, I cyc2_mult and Q cyc2_mult Perform integration / accumulation respectively to obtain the in-phase signal and quadrature-phase signal corresponding to the noise signal in cyc2 segment: cyc2 =cos(ωt+π)*sin(ωt)=0

[0152] The principles for other sections are the same and will not be repeated here.

[0153] The in-phase signal and quadrature-phase signal corresponding to the noise signal in each cyc segment are accumulated and processed, and the demodulation result corresponding to the same-frequency noise signal in the touch sensing signal is obtained as follows:

[0154] The modulus of the noise:

[0155] That is, the demodulated values ​​of the same-frequency noise in two adjacent second signal segments will have a positive and negative offset effect after being accumulated, thereby playing a role in suppressing the same-frequency noise.

[0156] For the valid signal in the second signal segment, since it is phase-synchronized with the corresponding demodulated signal segment, as shown in Figures 18 and 19, the demodulated values ​​of each segment are accumulated without any positive or negative offset, resulting in no energy loss. This reduces noise energy while maintaining signal energy, improving the signal-to-noise ratio in the presence of co-channel interference, and thus enhancing the sensitivity and accuracy of touch detection.

[0157] Sixth Example

[0158] This example differs from the fourth example in that the initial phases of two adjacent first signal segments in each drive signal's N first signal segments are the same, and the phase difference corresponding to the time interval between the two adjacent first signal segments is (2n+1)*π radians. Accordingly, the initial phases of two adjacent demodulated signal segments in the N demodulated signal segments included in the demodulated signal are the same, and the phase difference corresponding to the time interval between the two adjacent demodulated signal segments is (2n+1)*π radians. Furthermore, the touch sensing signal corresponding to each drive signal includes N second signal segments, each of which contains a valid signal and a co-frequency noise signal. The valid signal in each second signal segment is phase-synchronized with the corresponding first signal segment. For simplicity, the valid signal in the second signal segment and the corresponding first signal segment are represented using the same signal waveform. Since the co-frequency noise is assumed to be continuous during touch detection, and since the second signal segments correspond one-to-one with the first signal segments, the initial phase difference of the noise signal in two adjacent second signal segments is (2n+1)*π radians. Typically, when n = 0, the co-frequency noise in the first second signal segment can be expressed as sin(ωt), the co-frequency noise in the second second signal segment can be expressed as sin(ω*t+π), the co-frequency noise in the third second signal segment can be expressed as sin(ωt), and the co-frequency noise in the fourth second signal segment can be expressed as sin(ω*t+π). This cycle repeats until the Nth second signal segment. As shown in Figure 19, the time periods corresponding to the N first signal segments are respectively referred to as cyc1, cyc2, ..., cycN.

[0159] In this example, the multiplication, integration, and accumulation process of the quadrature demodulation of each first signal segment within each drive signal can refer to the self-capacitance detection method mentioned in the fifth example. For the N first signal segments within each drive signal, N corresponding quadrature demodulation values ​​I or Q can be obtained. By accumulating the N corresponding quadrature demodulation values ​​I or Q, a set of independent demodulation values ​​I and Q are obtained as the demodulation results. That is, for each drive signal, a demodulation result corresponding to the drive signal can be obtained.

[0160] Similar to the third example, the demodulated values ​​of the co-frequency noise signals in two adjacent second signal segments within each drive signal are accumulated to achieve a positive-negative cancellation effect. That is, in the demodulated results of the touch sensing signals corresponding to each drive signal, the impact of the co-frequency noise is at least partially eliminated, thereby suppressing the co-frequency noise. As for the valid signal in the second signal segment, since it is phase-synchronized with the corresponding demodulated signal segment, the accumulated demodulated values ​​of each segment do not experience positive-negative cancellation, resulting in no energy loss. This reduces noise energy while ensuring that signal energy remains unchanged, improving the signal-to-noise ratio in the presence of co-frequency interference and thus enhancing the sensitivity and accuracy of touch detection.

[0161] FIG20 shows a flow chart of a touch detection method according to an embodiment of the present application. The touch detection method is executed by the touch control chip 10 shown in FIG1 . As shown in FIG20 , the method includes:

[0162] S2001. Apply a driving signal to the touch sensor, where the driving signal includes N first signal segments of equal length, wherein initial phases of two adjacent first signal segments in the N first signal segments have a first phase difference, a third time interval exists between the two adjacent first signal segments, and a modulo 2π of the sum of the phase difference corresponding to the third time interval and the first phase difference is a preset phase value, where the preset phase value is greater than 0 and less than or equal to π, and N is an integer greater than or equal to 2.

[0163] S2002: Acquire a touch sensing signal corresponding to the driving signal from the touch sensor, where the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments;

[0164] S2003, demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal to obtain N demodulated data corresponding to the N second signal segments;

[0165] S2004 , performing accumulation processing on the N demodulated data to obtain a demodulation result of the touch sensing signal, so as to determine a touch detection result.

[0166] Similar to the embodiment shown in FIG8 , the drive signal in this embodiment has a drive frequency f and a drive period T, where T = 1 / f. The drive signal includes N first signal segments of equal length. Each first signal segment has a duration Tc, and the total duration of the drive signal is Tw1 = N * Tc. Each duration contains a signal waveform of k signal periods, i.e., Tc = K * T = k / f.

[0167] The difference between the embodiment of the present application and the embodiment shown in Figure 8 is that there is a first phase difference between the initial phases of two adjacent first signal segments in the N first signal segments, there is a third time interval between the two adjacent first signal segments, and the sum of the phase difference corresponding to the third time interval and the first phase difference modulo 2π is a preset phase value, and the preset phase value is greater than 0 and less than or equal to π.

[0168] The phase difference corresponding to the third time interval is a phase difference that may be generated when a signal having a preset frequency passes through the third time interval, and the preset frequency is equal to the driving frequency of the driving signal. Specifically, the phase difference corresponding to the third time interval has the following relationship with the third time interval: Φ t3 =2π*Ts3*f, where Φ t3 is the phase difference corresponding to the third time interval, Ts3 is the third time interval, and f is the driving frequency of the driving signal.

[0169] Similar to the aforementioned embodiment, in response to application of a driving signal to the touch sensor, each of the N second signal segments contained in a touch sensing signal obtained from the touch sensor includes both a valid signal that is phase-synchronized with the corresponding first signal segment and a co-frequency noise signal that is co-frequency with the driving signal. Because a demodulation signal that is phase-synchronized with the driving signal is used when demodulating the N second signal segments, the valid signal in each second signal segment is phase-synchronized with the corresponding demodulated signal segment. This ensures that the energy of the valid signal remains unchanged when the N demodulated data obtained by demodulating the N second signal segments are accumulated.

[0170] At the same time, because the co-channel noise signal is generally assumed to be continuous during the touch detection process, a third time interval exists between adjacent second signal segments in the N second signal segments corresponding one-to-one to the N first signal segments, resulting in the initial phases of the noise signals in the two adjacent second signal segments having a phase difference corresponding to the third time interval. Furthermore, because the initial phases of adjacent first signal segments in the N first signal segments have a first phase difference, adjacent demodulated signal segments in the N demodulated signals synchronized with the N first signal segments have a first phase difference. Therefore, the first phase difference and the phase difference corresponding to the third time interval result in a predetermined phase value modulo 2π, calculated as the difference between the initial phase difference between the co-channel noise signal in the preceding second signal segment and the corresponding demodulated signal segment, and the initial phase difference between the co-channel noise signal in the following second signal segment and the corresponding demodulated signal segment, for two adjacent second signal segments. The predetermined phase value is greater than 0 and less than or equal to π. This is equivalent to phase modulating the co-channel noise signal. Therefore, when demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the drive signal and accumulating the N demodulation results corresponding to the N second signal segments, there will be a positive and negative cancellation of the same-frequency noise energy. The noise energy will be at least partially cancelled, thereby reducing the same-frequency noise energy in the touch sensing signal.

[0171] In one embodiment of the present application, N is greater than or equal to the quotient of 2π and a preset phase value, thereby including at least one complete modulation cycle in the modulation process. This ensures that the co-frequency noise coupled to the touch detection system at any time point during the touch detection time can be better offset, thereby significantly reducing the co-frequency noise energy in the touch sensing signal.

[0172] In this embodiment, the size of the preset phase value and the size of N can be selected according to the characteristics of the same-frequency noise signal in the application scenario.

[0173] In one implementation of the present application, N is an integer multiple of the quotient of 2π and a preset phase value, which makes the modulation process include an integer multiple of the modulation period, so that the noise energy in the N second signal segments can be offset to the maximum extent, thereby significantly reducing the co-frequency noise energy in the touch sensing signal, maximizing the signal-to-noise ratio in the case of co-frequency interference, and thereby maximizing the sensitivity and accuracy of touch detection.

[0174] In one implementation of the present application, the preset phase value can be π, π / 2, or π / 4. This is equivalent to performing two-phase modulation, four-phase modulation, and eight-phase modulation on the co-frequency noise signal, respectively. By setting the preset phase value to π, π / 2, or π / 4, the sensitivity and accuracy of touch detection can be improved while reducing the amount of calculation.

[0175] For ease of understanding, the above process is described below with reference to FIG21 through the seventh example. In the seventh example, the self-capacitance detection method is used as an example based on the exemplary touch detection system shown in FIG1. ​​In the seventh example and the sixth example, it is assumed that the driving frequency of the driving signal is f, and the driving signal includes N first signal segments of equal length, each first signal segment contains k signal waveforms (k is a positive integer), the duration of each first signal segment is Tc, and Tc = k / f. The difference in initial phase between two adjacent first signal segments is π / 2 radians, and the phase difference corresponding to the third time interval Ts3 between two adjacent first signal segments is 3π / 2 radians. As shown in FIG21, the difference in initial phase between two adjacent first signal segments in the N first signal segments is π / 2 radians. Therefore, the N first signal segments are represented by cos(ωt), cos(ωt+π / 2), cos(ωt+π), and cos(ωt+3π / 2), respectively. The touch sensing signal corresponding to the drive signal includes N second signal segments. Each second signal segment contains a valid signal and a co-frequency noise signal. The valid signal in each second signal segment is phase-synchronized with the corresponding first signal segment. For simplicity, the valid signal in a second signal segment is represented by the signal waveform of the corresponding first signal segment. The phase difference corresponding to the third time interval between two adjacent first signal segments is 3π / 2 radians. Therefore, the phase difference corresponding to the time interval between two adjacent demodulated signal segments in the N demodulated signal segments is 3π / 2 radians.

[0176] In addition, since the same-frequency noise is considered to be continuous during touch detection, the third time interval makes the difference in the initial phase of the noise signal in two adjacent second signal segments be 3π / 2 radians. Typically, when n=0, the same-frequency noise in the first second signal segment can be expressed as sin(ωt), which is equivalent to the initial phase Φ n2 The same-frequency noise in the second signal segment can be expressed as sin(ω*t+3π / 2), which is equivalent to the initial phase Φ n2=3π / 2, the same frequency noise in the third second signal segment can be expressed as sin(ωt+3π)=sin(ωt+π), which is equivalent to the initial phase Φ n2 The same-frequency noise in the fourth second signal segment can be expressed as sin(ω*t+9π / 2)=sin(ωt+π / 2), which is equivalent to the initial phase Φ n2 The initial phase difference between two adjacent first signal segments and the third time interval between the two adjacent first signal segments are such that, for two adjacent first signal segments, the difference between the initial phase difference between the co-frequency noise signal in the preceding second signal segment and the corresponding demodulated signal segment and the difference between the initial phase difference between the co-frequency noise signal in the following second signal segment and the corresponding demodulated signal segment is π, and the modulo result of the difference with 2π is the preset phase value π.

[0177] Similar to Examples 2 through 6, the accumulated co-channel noise demodulation values ​​in two adjacent second signal segments cancel each other out, thus suppressing co-channel noise. For the valid signal in the second signal segment, since it is phase-synchronized with the corresponding demodulated signal segment, the accumulated demodulation values ​​of each segment do not cancel each other out, resulting in no energy loss. This reduces noise energy while maintaining signal energy, improving the signal-to-noise ratio in the presence of co-channel interference and enhancing the sensitivity and accuracy of touch detection.

[0178] The embodiment of the present application further provides a touch control chip 10, which includes:

[0179] A driving circuit 101 is configured to apply a driving signal to the touch sensor, the driving signal comprising N first signal segments of equal length, wherein the difference in initial phase between two adjacent first signal segments of the N first signal segments is a preset phase value, the preset phase value being greater than 0 and less than or equal to π, and N being a positive integer greater than or equal to the quotient of 2π and the preset phase value;

[0180] a receiving circuit 102 configured to obtain a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments;

[0181] The demodulation circuit 103 is configured to demodulate the N second signal segments using a demodulation signal that is phase-synchronized with the drive signal to obtain N demodulated data corresponding to the N second signal segments, and to accumulate the N demodulated data to obtain a demodulation result of the touch sensing signal for use in determining a touch detection result.

[0182] In a possible implementation, any two adjacent first signal segments among the N first signal segments are continuous in time.

[0183] In a possible implementation, there is a first time interval between any two adjacent first signal segments in the N first signal segments, and the phase difference corresponding to the first time interval is an integer multiple of 2π.

[0184] In a possible implementation, the first time interval is equal to an integer multiple of a driving period of the driving signal.

[0185] In a possible implementation, N is an integer multiple of a quotient of 2π and the preset phase value.

[0186] In a possible implementation, the preset phase value is one of π, π / 2 or π / 4.

[0187] The embodiment of the present application further provides a touch control chip 10, which includes:

[0188] A driving circuit 101 is configured to apply a driving signal to the touch sensor, the driving signal comprising N first signal segments of equal length, wherein two adjacent first signal segments of the N first signal segments have the same initial phase, a second time interval exists between the two adjacent first signal segments, a phase difference corresponding to the second time interval modulo 2π is a preset phase value, the preset phase value is greater than 0 and less than or equal to π, and N is a positive integer greater than or equal to the quotient of 2π and the preset phase value;

[0189] a receiving circuit 102 configured to obtain a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments;

[0190] The demodulation circuit 103 is configured to demodulate the N second signal segments using a demodulation signal that is phase-synchronized with the drive signal to obtain N demodulated data corresponding to the N second signal segments, and to accumulate the N demodulated data to obtain a demodulation result of the touch sensing signal for use in determining a touch detection result.

[0191] In a possible implementation, N is an integer multiple of a quotient of 2π and the preset phase value.

[0192] In a possible implementation, the preset phase value is one of π, π / 2 or π / 4.

[0193] In a possible implementation, the second time interval is (n+1 / 2)*T, (n+1 / 4)*T, or (n+1 / 4)*T, where T is the driving period of the driving signal.

[0194] The embodiment of the present application further provides a touch control chip 10, which includes:

[0195] A driving circuit 101 is configured to apply a driving signal to the touch sensor, the driving signal comprising N first signal segments of equal length, initial phases of two adjacent first signal segments of the N first signal segments having a first phase difference, a third time interval between the two adjacent first signal segments, a sum of the phase difference corresponding to the third time interval and the first phase difference modulo 2π forming a preset phase value, the preset phase value being greater than 0 and less than or equal to π, and N being a positive integer greater than or equal to the quotient of 2π and the preset phase value;

[0196] a receiving circuit 102 configured to obtain a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments;

[0197] The demodulation circuit 103 is configured to demodulate the N second signal segments using a demodulation signal that is phase-synchronized with the drive signal to obtain N demodulated data corresponding to the N second signal segments, and to accumulate the N demodulated data to obtain a demodulation result of the touch sensing signal for use in determining a touch detection result.

[0198] In a possible implementation, N is an integer multiple of a quotient of 2π and the preset phase value.

[0199] In a possible implementation, the preset phase value is one of π, π / 2 or π / 4.

[0200] The touch control chip of this embodiment is used to implement the corresponding touch detection methods in the aforementioned multiple method embodiments and has the beneficial effects of the corresponding method embodiments, which will not be described in detail here. In addition, the functional implementation of each module in the touch control chip of this embodiment can refer to the description of the corresponding parts in the aforementioned method embodiments, which will not be described in detail here.

[0201] An embodiment of the present application further provides a touch detection system, comprising a touch sensor and a touch chip as provided in any of the aforementioned embodiments.

[0202] The present application also provides an electronic device comprising a touch screen and the touch detection system according to claim 1. The electronic device may be a touch-interactive electronic device such as a laptop computer, tablet computer, smartphone, or smart speaker. The electronic device may also be an electronic device such as a headset or wearable device that has touch and pressure detection capabilities.

[0203] It should be pointed out that, according to the needs of implementation, the various components / steps described in the embodiments of the present application can be split into more components / steps, or two or more components / steps or partial operations of components / steps can be combined into new components / steps to achieve the purpose of the embodiments of the present application.

[0204] Those skilled in the art will appreciate that the units and method steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the embodiments of this application.

[0205] The above implementation methods are only used to illustrate the embodiments of the present application, and are not intended to limit the embodiments of the present application. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the embodiments of the present application. Therefore, all equivalent technical solutions also fall within the scope of the embodiments of the present application, and the scope of patent protection of the embodiments of the present application should be defined by the claims.

Claims

1. A touch detection method, include: Applying a driving signal to the touch sensor, the driving signal comprising N first signal segments of equal length, the difference between the initial phases of two adjacent first signal segments in the N first signal segments being a preset phase value, the preset phase value being greater than 0 and less than or equal to π, and N being an integer greater than or equal to 2; Acquire a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments; Demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal to obtain N demodulated data corresponding to the N second signal segments; Accumulation processing is performed on the N demodulated data to obtain a demodulation result of the touch sensing signal, so as to determine a touch detection result.

2. The method according to claim 1, in, Any two adjacent first signal segments among the N first signal segments are continuous in time.

3. The method according to claim 1, in, There is a first time interval between any two adjacent first signal segments in the N first signal segments, and the phase difference corresponding to the first time interval is an integer multiple of 2π.

4. The method according to claim 3, in, The N is greater than or equal to the quotient of 2π and the preset phase value.

5. The method according to claim 1, in, The N is an integer multiple of the quotient of 2π and the preset phase value.

6. The method according to claim 1, in, The preset phase value is one of π, π / 2 or π / 4.

7. A touch detection method, include: Applying a driving signal to the touch sensor, the driving signal comprising N first signal segments of equal length, the initial phases of two adjacent first signal segments of the N first signal segments being the same, a second time interval being present between the two adjacent first signal segments, a phase difference corresponding to the second time interval being modulo 2π being a preset phase value, the preset phase value being greater than 0 and less than or equal to π, and N being an integer greater than or equal to 2; Acquire a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments; Demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal to obtain N demodulated data corresponding to the N second signal segments; Accumulation processing is performed on the N demodulated data to obtain a demodulation result of the touch sensing signal, so as to determine a touch detection result.

8. [Corrected 24.11.2023 in accordance with Rule 26] A method according to claim 6, in, The N is greater than or equal to the quotient of 2π and the preset phase value.

9. The method according to claim 6, in, The N is an integer multiple of the quotient of 2π and the preset phase value.

10. The method according to claim 6, in, The preset phase value is one of π, π / 2 or π / 4.

11. The method according to claim 6, in, The second time interval is (n+1 / 2)*T, (n+1 / 4)*T or (n+1 / 4)*T, wherein T is the driving period of the driving signal.

12. A touch detection method, include: Applying a driving signal to the touch sensor, the driving signal comprising N first signal segments of equal length, initial phases of two adjacent first signal segments in the N first signal segments having a first phase difference, a third time interval existing between the two adjacent first signal segments, a sum of the phase difference corresponding to the third time interval and the first phase difference modulo 2π being a preset phase value, the preset phase value being greater than 0 and less than or equal to π, and N being an integer greater than or equal to 2; Acquire a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments; Demodulating the N second signal segments using a demodulation signal that is phase-synchronized with the driving signal, and generating N demodulation data corresponding to the N second signal segments; Accumulation processing is performed on the N demodulated data to obtain a demodulation result of the touch sensing signal, so as to determine a touch detection result. The method according to claim 12 , wherein N is greater than or equal to a quotient of 2π and the preset phase value.

14. The method according to claim 1, in, The N is an integer multiple of the quotient of 2π and the preset phase value.

15. The method according to claim 1, in, The preset phase value is one of π, π / 2 or π / 4.

16. The method according to any one of claims 1 to 15, in, The touch sensor is a self-capacitive touch sensor, and the self-capacitive touch sensor includes a plurality of independent detection electrodes, and a touch self-capacitance is formed between each detection electrode and the ground; The applying a driving signal to the touch sensor comprises: applying the driving signal to each of the plurality of detection electrodes respectively; The step of acquiring a touch sensing signal corresponding to the driving signal from the touch sensor includes: A touch sensing signal corresponding to the driving signal is received from each detection electrode respectively.

17. The method according to any one of claims 1 to 15, in, The touch sensor is a mutual capacitance touch sensor, and the mutual capacitance touch sensor includes a plurality of driving electrodes and a plurality of sensing electrodes arranged crosswise, and a touch mutual capacitance is formed between each driving electrode and each sensing electrode; The applying a driving signal to the touch sensor comprises: In the mutual capacitance single-channel detection mode, applying the driving signal to each driving electrode of the plurality of driving electrodes in sequence; The step of acquiring a touch sensing signal corresponding to the driving signal from the touch sensor includes: A touch sensing signal corresponding to the driving signal is received from each sensing electrode respectively.

18. The method according to any one of claims 1 to 15, in, The touch sensor is a mutual capacitance touch sensor, which includes a plurality of driving electrodes and a plurality of sensing electrodes arranged crosswise, and a touch mutual capacitance is formed between each driving electrode and each sensing electrode. The applying a driving signal to the touch sensor comprises: In the multi-channel mutual capacitance detection mode, the driving signal is applied to M driving electrodes of the multiple driving electrodes at the same time, and M driving signals are applied to each driving electrode of the M driving electrodes, the M target excitation codes are phase-encoded driving signals, and M is an integer greater than or equal to 2; Acquiring a touch sensing signal corresponding to the driving signal from the touch sensor includes: M touch sensing signals corresponding to the M driving signals are received from each of the sensing electrodes respectively.

19. A touch chip, include: A driving circuit, configured to apply a driving signal to the touch sensor, wherein the driving signal includes N first signal segments of equal length, wherein a difference in initial phases between two adjacent first signal segments among the N first signal segments is a preset phase value, wherein the preset phase value is greater than 0 and less than or equal to π, and N is an integer greater than or equal to 2; a receiving circuit, configured to obtain a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments; The demodulation circuit is used to demodulate the N second signal segments using a demodulation signal that is phase-synchronized with the drive signal to obtain N demodulation data corresponding to the N second signal segments, and to accumulate the N demodulation data to obtain a demodulation result of the touch sensing signal for determining a touch detection result.

20. The touch control chip according to claim 19, in, Any two adjacent first signal segments among the N first signal segments are continuous in time.

21. The touch control chip according to claim 19, in, There is a first time interval between any two adjacent first signal segments in the N first signal segments, and the phase difference corresponding to the first time interval is an integer multiple of 2π.

22. The touch control chip according to claim 19, in, Any two adjacent first signal segments among the N first signal segments are continuous in time.

23. The touch control chip according to claim 19, in, The N is greater than or equal to the quotient of 2π and the preset phase value.

24. The touch control chip according to claim 19, in, The N is an integer multiple of the quotient of 2π and the preset phase value.

25. The touch control chip according to claim 19, in, The preset phase value is one of π, π / 2 or π / 4.

26. A touch chip, include: A driving circuit, applying a driving signal to the touch sensor, wherein the driving signal includes N first signal segments of equal length, wherein the initial phases of two adjacent first signal segments of the N first signal segments are the same, and there is a second time interval between the two adjacent first signal segments, and a phase difference corresponding to the second time interval and a modulo result of 2π are a preset phase value, wherein the preset phase value is greater than 0 and less than or equal to π, and N is an integer greater than or equal to 2; a receiving circuit, configured to obtain a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments; The demodulation circuit is used to demodulate the N second signal segments using a demodulation signal that is phase-synchronized with the drive signal to obtain N demodulation data corresponding to the N second signal segments, and to accumulate the N demodulation data to obtain a demodulation result of the touch sensing signal for determining a touch detection result. 27 . The touch control chip according to claim 26 , wherein, N is greater than or equal to a quotient of 2π and the preset phase value.

28. The touch control chip according to claim 26, in, The N is an integer multiple of the quotient of 2π and the preset phase value.

29. The method according to claim 26, in, The preset phase value is one of π, π / 2 or π / 4.

30. The method according to claim 26, in, The second time interval is (n+1 / 2)*T, (n+1 / 4)*T or (n+1 / 4)*T, wherein T is the driving period of the driving signal.

31. A touch chip, include: A driving circuit, used for applying a driving signal to the touch sensor, wherein the driving signal comprises N first signal segments of equal length, wherein initial phases of two adjacent first signal segments in the N first signal segments have a first phase difference, and there is a third time interval between the two adjacent first signal segments, and a modulo result of a sum of the phase difference corresponding to the third time interval and the first phase difference and 2π is a preset phase value, wherein the preset phase value is greater than 0 and less than or equal to π, and N is an integer greater than or equal to 2; a receiving circuit, configured to obtain a touch sensing signal corresponding to the driving signal from the touch sensor, wherein the touch sensing signal includes N second signal segments corresponding one-to-one to the N first signal segments; The demodulation circuit is used to demodulate the N second signal segments using a demodulation signal that is phase-synchronized with the drive signal to obtain N demodulation data corresponding to the N second signal segments, and to accumulate the N demodulation data to obtain a demodulation result of the touch sensing signal for determining a touch detection result.

32. The touch control chip according to claim 31, in, The N is greater than or equal to the quotient of 2π and the preset phase value.

33. The touch control chip according to claim 31, in, The N is an integer multiple of the quotient of 2π and the preset phase value.

34. The touch control chip according to claim 32, in, The preset phase value is one of π, π / 2 or π / 4.

35. The touch control chip according to any one of claims 19 to 34, in, The touch sensor is a self-capacitive touch sensor, and the self-capacitive touch sensor includes a plurality of independent detection electrodes, and a touch self-capacitance is formed between each detection electrode and the ground; The applying a driving signal to the touch sensor comprises: applying the driving signal to each of the plurality of detection electrodes respectively; The step of acquiring a touch sensing signal corresponding to the driving signal from the touch sensor includes: A touch sensing signal corresponding to the driving signal is received from each detection electrode respectively.

36. The touch control chip according to any one of claims 19 to 34, in, The touch sensor is a mutual capacitance touch sensor, and the mutual capacitance touch sensor includes a plurality of driving electrodes and a plurality of sensing electrodes arranged crosswise, and a touch mutual capacitance is formed between each driving electrode and each sensing electrode; The applying a driving signal to the touch sensor comprises: In the mutual capacitance single-channel detection mode, applying the driving signal to each driving electrode of the plurality of driving electrodes in sequence; The step of acquiring a touch sensing signal corresponding to the driving signal from the touch sensor includes: A touch sensing signal corresponding to the driving signal is received from each sensing electrode respectively.

37. The touch control chip according to any one of claims 19 to 34, in, Applying M of the driving signals, wherein the M target excitation codes are phase-encoded driving signals, and M is an integer greater than or equal to 2; Acquiring a touch sensing signal corresponding to the driving signal from the touch sensor includes: M touch sensing signals corresponding to the M driving signals are received from each of the sensing electrodes respectively.

38. A touch detection system, comprising a touch sensor and a touch chip as claimed in any one of claims 19 to 37.

39. An electronic device comprising a touch screen and the touch detection system according to claim 38.

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