Touch detection circuit

Abstract

The invention provides a touch detection circuit which comprises a plurality of driving signal generators. The driving signal generators are divided into a plurality of driving signal generator groups, and each driving signal generator group comprises at least one driving signal generator. The driving signal generators respectively generate a plurality of driving signals, and the frequency of each driving signal in one driving signal generator group is different from the frequency of each driving signal in the other driving signal generator group.

Description

Technical Field

[0001] The present invention relates to a touch detection circuit, and more particularly to a touch detection circuit capable of reducing noise interference. Background Art

[0002] In current electronic products, a touch detection circuit is an essential circuit for most products. For example, as mobile phones become thinner and thinner, the distance between the touch panel and the display panel gets closer and closer. The introduced noise becomes larger and larger, and the touch detection circuit is more vulnerable to interference. Summary of the Invention

[0003] The present invention is directed to a touch detection circuit that can shorten the time of a touch sensing operation and improve the signal-to-noise ratio (SNR) of a touch sensing signal.

[0004] According to an embodiment of the present invention, the touch detection circuit includes a plurality of drive signal generators. The drive signal generators are divided into a plurality of drive signal generator groups, and each of the drive signal generator groups includes at least one drive signal generator. The drive signal generators respectively generate a plurality of drive signals, and the frequencies of the drive signals in each of the drive signal generator groups are different from the frequencies of the drive signals in another drive signal generator group.

[0005] Based on the above, the drive signal generators of the touch detection circuit are configured to generate drive signals that swing between a positive voltage and a negative voltage. That is to say, the rising amplitude of the drive signal from the disabled state to the enabled state of the drive signal generator may be reduced. Thus, the interference of low-frequency noise can be reduced, and the performance of the touch sensing device can be enhanced. Brief Description of the Drawings

[0006] Figure 1 A schematic diagram illustrating a touch detection circuit according to an embodiment of the present disclosure.

[0007] Figure 2 A waveform diagram illustrating drive signals generated by a drive signal generator of a touch detection circuit according to an embodiment of the present disclosure.

[0008] Figure 3 is according to the present disclosure Figure 2 A spectrogram of an embodiment.

[0009] Figure 4 A schematic diagram of a touch sensing device according to an embodiment of the present disclosure.

[0010] Figure 5 A circuit diagram illustrating each of the sense signal receivers according to an embodiment of the present disclosure.

[0011] Figure 6Illustrate the waveform diagram of the drive signal generated by the drive signal generator of the touch detection circuit according to another embodiment of the present disclosure.

[0012] Figure 7 is the spectrogram according to the present disclosure Figure 6 embodiment.

[0013] Figure 8 Schematic diagram illustrating the touch sensing operation according to an embodiment of the present disclosure.

[0014] Figure 9 Schematic diagram illustrating the drive signal waveform according to another embodiment of the present disclosure.

[0015] Figure 10 Illustrate the waveform diagram of the drive signal generated by the drive signal generator of the touch detection circuit according to another embodiment of the present disclosure.

[0016] Figure 11 Illustrate according to the present disclosure Figure 10 embodiment spectrogram. Detailed Description of the Invention

[0017] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used in the drawings and the description to refer to the same or like parts.

[0018] Please refer to Figure 1 , which illustrates a schematic diagram of a touch detection circuit according to an embodiment of the present disclosure. The touch detection circuit 100 includes a plurality of drive signal generators 111 to 11N. The drive signal generators 111 to 11N can be divided into a plurality of drive signal generator groups G1 to GM. Herein, each of the drive signal generator groups G1 to GM includes one or more of the drive signal generators 111 to 11N. For example, the drive signal generator group G1 includes the drive signal generators 111 to 11A; the drive signal generator group G1 includes the drive signal generators 11A + 1 to 11B;...; and the drive signal generator group GM includes the drive signal generators 11C + 1 to 11N.

[0019] On the other hand, the drive signal generators 111 to 11N respectively generate a plurality of drive signals TX1 to TXN. The frequency of each of the drive signals TX1 to TXN of one group among the drive signal generator groups G1 to GM is different from the frequency of each of the drive signals TX1 to TXN of another group among the drive signal generator groups G1 to GM.

[0020] Specifically, in this embodiment, the drive signals TX1 to TXA correspond to the same drive signal generator group G1; the drive signals TXA+1 to TXB correspond to the same drive signal generator group G2;...; and the drive signals TXC to TXN correspond to the same drive signal generator group GM. The frequencies of the drive signals TX1 to TXA corresponding to the same drive signal generator group G1 may be the same and equal to the first frequency; the frequencies of the drive signals TXA+1 to TXB corresponding to the same drive signal generator group G2 may be the same and equal to the second frequency;...; and the frequencies of the drive signals TXC to TXN corresponding to the same drive signal generator group GM may be the same and equal to the Mth frequency, where any two of the first frequency to the Mth frequency are different.

[0021] Please refer jointly to Figure 2 , which illustrates the waveform diagrams of the drive signals generated by the drive signal generators of the touch detection circuit according to the embodiments of the present disclosure. In Figure 2 , a plurality of drive signals TX1 to TX12 are generated by a plurality of drive signal generators. The drive signals TX1 to TX12 may correspond to three drive signal generator groups G1 to G3. Specifically, the drive signals TX1 to TX4 may correspond to the drive signal generator group G1; the drive signals TX5 to TX8 may correspond to the drive signal generator group G2; and the drive signals TX9 to TX12 may correspond to the drive signal generator group G3. In this embodiment, the number of drive signals in the drive signal generator groups G1 to G3 is the same.

[0022] During the touch sensing operation, the drive signals TX1 to TX12 may be divided into a plurality of cycles along the time axis. These cycles respectively correspond to a plurality of time periods TP1 to TP4. In the time period TP1, the drive signals TX1, TX5, and TX9 are enabled and have an amplitude swing between two different voltages, while the other drive signals TX2 to TX4, TX6 to TX8, and TX10 to TX12 are disabled and held at the reference voltage. In the time period TP2, the drive signals TX2, TX6, and TX10 are enabled and have an amplitude swing between two different voltages, while the other drive signals TX1, TX3 to TX5, TX7 to TX9, TX11, and TX12 are disabled and held at the reference voltage. In the time period TP3, the drive signals TX3, TX7, and TX11 are enabled and have an amplitude swing between two different voltages, while the other drive signals TX1, TX2, TX4 to TX6, TX8 to TX10, and TX12 are disabled and held at the reference voltage. In the time period TP4, the drive signals TX4, TX8, and TX12 are enabled and have an amplitude that swings between two different voltages, while the other drive signals TX1 to TX3, TX5 to TX7, and TX9 to TX11 are disabled and held at the reference voltage.

[0023] It should be noted that in one of the time periods TP1 to TP4, only one driving signal in each of the driving signal generator groups G1 to G3 is enabled. In addition, the enabled driving signal corresponding to the driving signal generator group G1 has a first frequency, the enabled driving signal corresponding to the driving signal generator group G2 has a second frequency, and the enabled driving signal corresponding to the driving signal generator group G3 has a third frequency, where the first frequency, the second frequency, and the third frequency are different.

[0024] It should also be noted that in this embodiment, multiple driving signals can be enabled simultaneously within the same time period. For example, during the time period TP1, the driving signals TX1, TX5, and TX9 are simultaneously enabled. Thus, the time length of one frame of the touch sensing operation can be reduced. It can be seen that in this embodiment, one frame of the touch sensing operation only requires 4 time periods TP1 to TP4, rather than 12 time periods.

[0025] Since the total sensing time can be saved, the time length of each of the time periods TP1 to TP4 can be increased. Thus, the signal-to-noise ratio (SNR) of the driving signals TX1 to TX12 and the corresponding sensing signals can be increased, and the performance of the touch sensing operation can be enhanced.

[0026] On the other hand, in the present disclosure, the amplitudes of the enabled driving signals TX1 to TX12 may be the same. Each of the enabled driving signals TX1 to TX12 may be a sine wave, a square wave, a triangular wave, or any other periodic wave. Each of the disabled driving signals TX1 to TX12 may be held at the ground voltage (= 0V). In addition, the number of the driving signal generator groups can be set by the designer according to actual needs, and there is no particular limitation here.

[0027] In this embodiment, each of the driving signal generators can be implemented by a signal selector. When the driving signals TX1 to TX12 are disabled, the signal selector can select the ground voltage to generate the corresponding driving signals TX1 to TX12. When the driving signals TX1 to TX12 are enabled, the signal selector can select a pre-generated sine wave to generate the corresponding driving signals TX1 to TX12. The signal selector can be implemented by any signal multiplexing circuit well-known to those skilled in the art, and there is no particular limitation.

[0028] Please refer to Figure 3 , which is a spectrogram according to an embodiment of the present disclosure Figure 2 . According to Figure 2The waveforms corresponding to the enabled drive signals TX1 to TX4 of the drive signal generator group G1 have a frequency f0; the waveforms corresponding to the enabled drive signals TX5 to TX8 of the drive signal generator group G2 have a frequency f1; the waveforms corresponding to the enabled drive signals TX9 to TX12 of the drive signal generator group G3 have a frequency f2, where frequency f2 < frequency f0 < frequency f1. Three independent spectra SP0 to SP2 corresponding to the frequencies f0 to f2 can be seen on the spectrogram.

[0029] In addition, Figure 3 the spectrogram in can be obtained by performing a Fourier transform on the drive signals TX1 to TX12.

[0030] Please refer to Figure 4 , which is a schematic diagram of a touch sensing device according to an embodiment of the present disclosure. The touch sensing device 400 includes a plurality of drive signal generators 411 to 41C, a plurality of sense signal receivers 421 to 424, and a touch sensing panel array 430. The touch sensing panel array 430 includes a plurality of touch sensing panels TD. The touch sensing panels TD can be arranged in an array. The drive signal generators 411 to 41C are coupled to the touch sensing panel array 430. The drive signal generators 411 to 41B respectively provide a plurality of drive signals to the corresponding touch sensing panels TD. The drive signal generators 411 to 414 are grouped into a drive signal generator group G1; the drive signal generators 415 to 418 are grouped into a drive signal generator group G2; the drive signal generators 419 to 41C are grouped into a drive signal generator group G3. The sense signal receivers 421 to 424 are also coupled to the touch sensing panel array 430. Each of the sense signal receivers 421 to 424 is configured to receive a sense signal from the corresponding touch sensing panel TD, and the sense signal is generated by the corresponding touch sensing panel TD based on the received drive signal.

[0031] Please refer to Figure 5 , which illustrates the circuit diagrams of the respective sense signal receivers according to an embodiment of the present disclosure. Figure 4 Each of the sense signal receivers 421 to 424 in can be formed by Figure 5is implemented by the sensing signal receiver 500. The sensing signal receiver 500 includes a signal adder 510, an analog front-end circuit 520, a plurality of filters 531 to 533, and a signal processing circuit 540. The signal adder 510 can receive a plurality of sensing signals SS1 to SS3 through a plurality of capacitors CA1 to CA3. The sensing signals SS1 to SS3 are respectively generated according to driving signals corresponding to different driving signal generator groups. Thus, the sensing signals SS1 to SS3 can respectively have different frequencies f0 to f2. The capacitors CA1 to CA3 are direct current (DC) decoupling capacitors, and the DC components of the sensing signals SS1 to SS3 can be filtered out. In this embodiment, the noise NS can also be received by the signal adder 510. The signal adder 510 sums the received signals and obtains a sum signal S1.

[0032] The analog front-end circuit 520 is coupled to the output terminal of the signal adder 510. The analog front-end circuit 520 can include a capacitor C1 and an amplifier AP1. The capacitor C1 is cross-coupled between the input terminal and the output terminal of the amplifier AP1. The amplifier AP1 is configured to amplify the sum signal S1 to generate a processed signal S2. In this embodiment, the processed signal S2 can be composed of a plurality of parts having frequencies f0, f1, and f2.

[0033] In addition, the filters 531 to 533 are coupled to the analog front-end circuit 520. The filters 531 to 533 respectively have a plurality of different filter bands fB0, fB1, and fB2. In this embodiment, any two of the filter bands fB0, fB1, and fB2 do not overlap. In addition, the filter bands fB0, fB1, and fB2 can be respectively set according to the frequencies f0 to f2 of the driving signals of the driving signal generator groups. Each of the frequencies f0 to f2 can be the intermediate frequency of each of the filter bands fB0, fB1, and fB2.

[0034] The filters 531 to 533 receive the processed signal S2 and respectively perform signal filtering operations on the processed signal S2 to respectively generate a plurality of filtered signals FS1 to FS3, and provide the filtered signals FS1 to FS3 to the signal processing circuit 540.

[0035] The signal processing circuit 540 can include a signal selector 541 and an analog-to-digital converter (ADC) 542. The signal selector 541 can select each of the filtered signals FS1 to FS3 and provide it to the ADC 542. The ADC 542 can convert each of the filtered signals FS1 to FS3 into a corresponding digital code. The sensing signal receiver 500 can generate touch sensing information according to the digital codes generated by the ADC 542.

[0036] In this embodiment, the signal adder 510 can be implemented by a signal summing circuit well-known to those skilled in the art. The amplifier AP1 can also be implemented by any type of amplifier well-known to those skilled in the art. The filters 531 to 533 are narrowband filters and can also be implemented by any known narrowband filtering circuit, and there is no special limitation here.

[0037] Please refer to Figure 6 , which illustrates the waveform diagram of the driving signals generated by the driving signal generator of the touch detection circuit according to another embodiment of the present disclosure. In this embodiment, a plurality of driving signals TX1 to TX12 are generated by a plurality of driving signal generators, and the driving signals TX1 to TX12 can correspond to three groups of driving signal generators G1 to G3.

[0038] During the touch sensing operation, the driving signals TX1 to TX12 can be divided into a plurality of cycles along the time axis. The cycles respectively correspond to a plurality of time periods TP1 to TP4. In this embodiment, the driving signals TX1 to TX12 are always enabled during all the time periods TP1 to TP4. In addition, in each of the groups of driving signal generators G1 to G3, at least one of the driving signals TX1 to TX12 has a first phase during each of the time periods TP1 to TP4, while the other driving signals TX1 to TX12 have a second phase during each of the time periods TP1 to TP4, where the first phase is different from the second phase.

[0039] Specifically, during the time period TP1, in the group of driving signal generators G1, the driving signal TX4 has a first phase (i.e., a negative phase), while the other driving signals TX1 to TX3 have a second phase (i.e., a positive phase). During the time period TP1, in the group of driving signal generators G2, the driving signal TX8 has a negative phase, while the other driving signals TX5 to TX7 have a positive phase. In addition, during the time period TP1, in the group of driving signal generators G3, the driving signal TX12 has a negative phase, while the other driving signals TX9 to TX11 have a positive phase.

[0040] During the next time period TP2, the driving signals with the first phase in each of the driving signal generator groups G1 to G3 may change. In this embodiment, during the time period TP2, the driving signals TX3, TX7, and TX11 are adjusted to a negative phase, while the other driving signals TX1 to TX2, TX4 to TX6, TX8 to TX10, and TX12 have a positive phase. During the time period TP3, the driving signals TX2, TX6, and TX10 are adjusted to a negative phase, while the other driving signals TX1, TX2 to TX5, TX7 to TX9, TX11, and TX12 have a positive phase. In addition, during the time period TP4, the driving signals TX1, TX5, and TX9 are adjusted to a negative phase, while the other driving signals TX2 to TX4, TX6 to TX8, and TX10 to TX12 have a positive phase.

[0041] In this embodiment, one frame of the touch sensing operation can be completed from the time period TP1 to the time period TP4.

[0042] It should be noted that the driving signals TX1 to TX12 of the same driving signal generator groups G1 to G3 may have the same frequency. The frequencies of the driving signals TX1 to TX4 corresponding to the driving signal generator group G1 may be a first frequency; the frequencies of the driving signals TX5 to TX8 corresponding to the driving signal generator group G2 may be a second frequency; the frequencies of the driving signals TX9 to TX12 corresponding to the driving signal generator group G3 may be a third frequency, where the first frequency, the second frequency, and the third frequency are different. In this embodiment, the first frequency < the second frequency < the third frequency.

[0043] It should be noted that in this embodiment, for example, each of the driving signal generators may receive two signals having a first phase and a second phase respectively. Each of the driving signal generators may receive one of the two signals to generate a corresponding driving signal. The signal selection operation may be performed by a signal multiplexer well-known to those skilled in the art.

[0044] Please refer to Figure 7 , which is a spectrogram according to the present disclosure Figure 6 embodiment. According to Figure 6 the waveform, each of the enabled driving signals TX1 to TX4 corresponding to the driving signal generator group G1 has a frequency f0; each of the enabled driving signals TX5 to TX8 corresponding to the driving signal generator group G2 has a frequency f1; each of the enabled driving signals TX9 to TX12 corresponding to the driving signal generator group G3 has a frequency f2, where the frequency f2 > the frequency f1 > the frequency f0. Three independent spectra SP0 to SP2 corresponding to the frequencies f0 to f2 can be seen on the spectrogram.

[0045] Figure 7The spectrogram therein can be obtained by performing a Fourier transform on the drive signals TX1 to TX12.

[0046] Please refer to Figure 6 and Figure 8 where Figure 8 illustrates a schematic diagram of a touch sensing operation according to an embodiment of the present disclosure. In Figure 8 during the touch sensing period STP1, drive signals TX1 - TX4 having phases -, +, +, + can be transmitted to the touch sensing panels TD1 - TD4. The sensing signal receiver RX1 corresponding to the touch sensing panels TD1 - TD4 can receive the sensing signal w from the touch sensing panels TD1 - TD4 during the touch sensing period STP1. During the touch sensing period STP2, drive signals TX1 - TX4 having phases +, -, +, + can be transmitted to the touch sensing panels TD1 - TD4. The sensing signal receiver RX1 can receive the sensing signal x from the touch sensing panels TD1 - TD4 during the touch sensing period STP2. During the touch sensing period STP3, drive signals TX1 - TX4 having phases +, +, -, + can be transmitted to the touch sensing panels TD1 - TD4. The sensing signal receiver RX1 can receive the sensing signal y from the touch sensing panels TD1 - TD4 during the touch sensing period STP3. In addition, during the touch sensing period STP4, drive signals TX1 - TX4 having phases +, +, +, - can be transmitted to the touch sensing panels TD1 - TD4. The sensing signal receiver RX1 can receive the sensing signal z from the touch sensing panels TD1 - TD4 during the touch sensing period STP4. In this embodiment, the sensing signals w, x, y, z can be generated respectively according to the capacitance change values a, b, c, d of the corresponding drive signals TX1 to TX4 and the touch sensing panels TD1 - TD4.

[0047] The relationship between the sensing signals w, x, y, z and the capacitance change values a, b, c, d can be expressed by the following formula:

[0048]

[0049] By expanding the above matrix operations, the following system of equations can be obtained:

[0050]

[0051] In this way, through the system of equations shown above, the capacitance change values a, b, c, d can be obtained, and touch information can be generated according to the capacitance change values a, b, c, d.

[0052] It should be noted that in this embodiment, one of the drive signals TX1 - TX4 is selected to have a different phase (the first phase). In some other embodiments, two or more of the drive signals TX1 - TX4 may be selected to have the first phase. In addition, one signal generator group may have two or more drive signal generators. The four drive signal generators in one signal generator group in this embodiment are only examples for illustration and do not limit the scope of the invention of the present disclosure.

[0053] Please refer to Figure 9 , which is a schematic diagram showing the drive signal waveform according to another embodiment of the present disclosure. In Figure 9 , the frequency of the drive signal TX may not be fixed at a constant value, but may be adjusted through a frequency spreading mechanism within a frequency band. In the time domain, the period of the drive signal TX may be T0 - ΔT, and is sequentially adjusted to T0, T0 + ΔT, T0, and T0 - ΔT. Thus, in the frequency domain, the frequency may vary within the frequency band 911 shown in the spectrogram 910. The lower limit of the frequency band 911 is f0 - Δf; the upper limit of the frequency band 911 is f0 + Δf; the center frequency of the frequency band 911 is f0. Wherein, f0 = 1 / T0; f0 + Δf = 1 / (T0 + ΔT); f0 - Δf = 1 / (T0 - ΔT).

[0054] Figure 9 , the waveform of the drive signal TX can be applied to each of the above - described embodiments of the present disclosure. The waveform of the drive signal TX can be generated by any frequency spreading circuit well - known to those skilled in the art, and there is no special limitation here.

[0055] Please refer to Figure 10 , which is a waveform diagram of the drive signal generated by the drive signal generator of the touch - detection circuit according to another embodiment of the present disclosure. In this embodiment, a plurality of drive signals TX1 to TX12 are generated by a plurality of drive signal generators, and the drive signals TX1 to TX12 can correspond to three drive signal generator groups G1 to G3.

[0056] In Figure 10 , the frequency spreading scheme described in the Figure 9 embodiment can be applied to generate the drive signals TX1 to TX12. In this embodiment, the frequencies of the drive signals TX1 to TX4 of the drive signal generator group G1 are modulated within the first frequency band; the frequencies of the drive signals TX5 to TX8 of the drive signal generator group G2 are modulated within the second frequency band; and the frequencies of the drive signals TX9 to TX12 of the drive signal generator group G3 are modulated within the third frequency band, where the first frequency band, the second frequency band, and the third frequency band do not overlap.

[0057] Please refer to Figure 11 , which illustrates the spectrogram according to the Figure 10 embodiment of the present disclosure. InFigure 11 Among them, the first frequency band SB0 has a center frequency f0, the second frequency band SB1 has a center frequency f1, and the third frequency band SB2 has a center frequency f2. The frequency f0 is less than the frequency f1, and the frequency f1 is less than the frequency f2.

[0058] Figure 11 The spectrogram of can be generated by performing a Fourier transform on the drive signals TX1 to TX12.

[0059] In summary, the present disclosure divides the drive signal generator into multiple drive signal generator groups, and the drive signal generators of different drive signal generator groups respectively generate drive signals with different frequencies. In this way, the total time length of the touch sensing operation can be saved, so the sensing operation time length of one channel can be increased. In this way, the signal-to-noise ratio of the drive signal and the corresponding sensing signal can be increased, the performance of the touch sensing operation can be enhanced, and the performance of the touch sensing operation can also be enhanced.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. Touch detection circuit, comprising: A plurality of drive signal generators, wherein the drive signal generators are divided into a plurality of drive signal generator groups, and each of the drive signal generator groups includes at least one of the drive signal generators, wherein the drive signal generators respectively generate a plurality of drive signals, and the frequencies of the drive signals within one group of the drive signal generator groups are different from the frequencies of the drive signals within another drive signal generator group.

2. The touch detection circuit according to claim 1, wherein the frequencies of the drive signals within the same drive signal generator group are equal.

3. The touch detection circuit according to claim 1, wherein the frequencies of the drive signals within each of the drive signal generator groups are modulated within a frequency band.

4. The touch detection circuit according to claim 3, wherein the frequency bands of any two of the drive signal generator groups do not overlap.

5. The touch detection circuit according to claim 3, wherein the frequencies of the drive signals within each of the drive signal generator groups are modulated according to a frequency spreading scheme.

6. The touch detection circuit according to claim 1, wherein each of the enabled drive signal generators generates a corresponding drive signal, and the amplitude of the drive signal swings between a first voltage and a second voltage, wherein the first voltage and the second voltage are different.

7. The touch detection circuit according to claim 6, wherein each of the disabled drive signal generators generates a corresponding drive signal, and the amplitude of the drive signal remains at a reference voltage.

8. The touch detection circuit according to claim 7, wherein at least two drive signal generators in different drive signal generator groups are enabled simultaneously.

9. The touch detection circuit according to claim 1, wherein within each of the drive signal generator groups, at least one drive signal has a first phase and the other drive signals have a second phase, and the first phase is different from the second phase.

10. The touch detection circuit according to claim 9, wherein each of the drive signals has the first phase during a first time period and has the second phase during a plurality of second time periods.

11. The touch detection circuit according to claim 1, wherein the drive signal generators respectively provide the plurality of drive signals to a plurality of touch sensing plates.

12. The touch detection circuit according to claim 11, further comprising: A plurality of sensing signal receivers, respectively receiving a plurality of sensing signals from the corresponding plurality of touch sensing plates and generating touch sensing information according to the plurality of sensing signals.

13. The touch detection circuit according to claim 12, wherein each of the signal sensing receivers includes: A signal adder, summing the corresponding sensing signals to obtain a sum signal; An analog front-end circuit, coupled to the signal adder, processing the sum signal to generate a processed signal; and A plurality of filters, coupled to the analog front-end circuit, wherein the filters respectively perform signal filtering operations on the processed signal to respectively generate a plurality of filtered signals. Among them, the filters respectively have a plurality of different filtering bands, and any two of the filtering bands do not overlap.

14. The touch detection circuit according to claim 13, wherein the filter is a narrowband filter.

15. The touch detection circuit according to claim 13, wherein the filtering bands are respectively set according to the frequencies of the driving signals of the driving signal generator group.

16. The touch detection circuit according to claim 13, wherein each of the signal sensing receivers further comprises: A signal processing circuit, which receives the filtered signal and performs operations on the filtered signal to obtain the touch sensing information.

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