Circuitry integrating touch controller and antenna and electronic device

Abstract

The application provides a circuit system integrating a touch controller and an antenna and an electronic device, wherein the circuit system integrating the touch controller and the antenna comprises a first mainboard, a second mainboard and an antenna; the first mainboard comprises a radio frequency module, a first series capacitor and a first matching circuit; the second mainboard comprises a touch controller and an LC low-pass filter circuit; one end of the first series capacitor is connected with the radio frequency module, the other end is connected with the first matching circuit, the other end of the first matching circuit is connected with the antenna; one end of the LC low-pass filter circuit is connected with the touch controller, the other end is connected with the antenna; wherein the first matching circuit is used for matching the impedance of the radio frequency module with the impedance of the antenna, the LC low-pass filter circuit is used for blocking high frequency signals of the radio frequency module higher than a first preset frequency from entering the touch controller, and the first series capacitor is used for blocking low frequency signals generated by the touch controller lower than a second preset frequency. The technical scheme can avoid mutual interference of the touch controller, the radio frequency module and the antenna.

Description

Technical Field

[0001] This application relates to the field of electronic device technology, and in particular to a circuit system and electronic device that integrates a touch controller and an antenna. Background Technology

[0002] As electronic devices (such as smart glasses and smart rings) become smaller and thinner, their internal space becomes extremely compact. Within this limited space, the layout of multiple functional modules faces significant challenges. Among these, the coexistence and interference issues of the touch controller, radio frequency module, and antenna are particularly prominent.

[0003] Specifically, because the metal connecting the antenna and the touch controller is made of the same material, conducted interference is easily generated during signal transmission. Furthermore, if the touch controller, RF module, and antenna are placed too close together in the layout, the electromagnetic waves emitted by both during operation will couple with each other spatially, causing coupling interference. Related technologies typically attempt to mitigate this problem by increasing the physical distance, but this is difficult to implement in small electronic devices. Therefore, a new circuit design is urgently needed to solve the technical problem of mutual interference between the touch controller, RF module, and antenna. Utility Model Content

[0004] This application provides a circuit system and electronic device that integrates a touch controller and an antenna to solve the technical problem of mutual interference between the touch controller, the radio frequency module and the antenna.

[0005] In a first aspect, a circuit system integrating a touch controller and an antenna is provided, comprising a first motherboard, a second motherboard, and an antenna; the first motherboard includes a radio frequency module, a first series capacitor, and a first matching circuit; the second motherboard includes a touch controller and an LC low-pass filter circuit; one end of the first series capacitor is connected to the radio frequency module, and the other end is connected to the first matching circuit, the other end of the first matching circuit being connected to the antenna; one end of the LC low-pass filter circuit is connected to the touch controller, and the other end is connected to the antenna; wherein, the first matching circuit is used to match the impedance of the radio frequency module with the impedance of the antenna, the LC low-pass filter circuit is used to block high-frequency signals from the radio frequency module that are higher than a first preset frequency from entering the touch controller, and the first series capacitor is used to block low-frequency signals generated by the touch controller that are lower than a second preset frequency.

[0006] By setting a first series capacitor, the touch signal generated by the touch controller can be limited to propagating only along the antenna path and not flowing back into the RF module. By setting a first matching circuit, impedance matching between the RF module and the antenna can be achieved. When the impedance of the antenna matches the impedance of the RF module, the RF signal of the RF module can be efficiently transmitted to the antenna and radiated out, thereby effectively reducing energy loss and waveform distortion of the RF signal during transmission. By setting an LC low-pass filter circuit to block high-frequency signals higher than the first preset frequency from the RF module from entering the touch controller, two potential risks can be avoided: first, high-frequency signals may interfere with the highly sensitive touch controller, causing touch recognition failure or false triggering; second, the energy of high-frequency signals may overload or saturate the internal circuitry of the touch controller. In summary, this integrated touch controller and antenna circuit system, through the coordinated design of matching, filtering, and isolation circuits, achieves stable coexistence and non-interference between RF communication and touch control functions in a highly integrated environment, effectively improving the overall system reliability and communication quality.

[0007] In conjunction with the first aspect, in one possible implementation, the antenna includes an antenna ground pin and an antenna feed pin, and the other end of the first matching circuit is connected to the antenna feed pin; the circuit system integrating the touch controller and the antenna further includes: a second matching circuit; one end of the second matching circuit is connected to the antenna ground pin, and the other end is connected to the ground point of the first motherboard, and the second matching circuit is used to match the impedance of the radio frequency signal path from the antenna ground pin to the ground point of the first motherboard.

[0008] When the antenna requires grounding, not only must the main loop path between the RF module and the antenna (i.e., the path from the RF module to the antenna feed pin) be unobstructed, but the ground loop path (i.e., the path from the first motherboard ground point to the antenna ground pin) must also be unobstructed. Only then can the RF signal be transmitted from the RF module to the antenna and radiated most effectively. By setting up this second matching circuit, the impedance of the ground loop path is adjusted to near zero impedance by utilizing the tuning effect of the inductors and / or capacitors contained within the second matching circuit. This ensures that the RF signal from the RF module can smoothly pass through the ground loop. This second matching circuit, in conjunction with the first matching circuit, allows the RF signal to be transmitted from the RF module to the antenna and radiated most effectively.

[0009] In conjunction with the first aspect, in one possible implementation, the circuit system integrating the touch controller and the antenna further includes: a second series capacitor; one end of the second series capacitor is connected to the antenna ground pin, and the other end is connected to the ground point of the motherboard. The second series capacitor is used to provide a grounding path for the radio frequency signal of the antenna within a preset frequency range and to block signals below the second preset frequency of the touch controller, thereby preventing the signal of the touch controller from being short-circuited to ground.

[0010] When the antenna requires grounding, the second series capacitor is configured to exhibit distinct impedance characteristics for the radio frequency (RF) signal and the touch signal from the touch controller: it establishes a grounding path for the RF signal within a preset frequency range, ensuring the integrity and efficiency of the antenna's radiation mode; and it blocks the touch signal from the touch controller (i.e., signals below the second preset frequency of the touch controller), creating a short circuit to ground. This second series capacitor ensures a good grounding of the antenna's RF signal while preventing the touch signal from attenuating due to shunting to ground, thus creating a frequency-selective dedicated grounding path for the integrated touch controller and antenna circuit system.

[0011] In conjunction with the first aspect, in one possible implementation, the capacitance values ​​of the first series capacitor and the second series capacitor are determined based on the frequency value of the radio frequency module and the capacitance value range of the first series capacitor and the second series capacitor, as well as the corresponding parasitic parameters.

[0012] In conjunction with the first aspect, in one possible implementation, the capacitance values ​​of both the first series capacitor and the second series capacitor are in the range of 27pF-80pF.

[0013] In conjunction with the first aspect, in one possible implementation, the antenna is a grounded antenna, which includes any one or more of a PIFA antenna, a LOOP antenna, and an IFA antenna.

[0014] In conjunction with the first aspect, in one possible implementation, the antenna is a monopole antenna.

[0015] In conjunction with the first aspect, in one possible implementation, the antenna is a radiator manufactured using any one of the following processes: flexible circuit board manufacturing, laser direct forming, or metal stamping.

[0016] In conjunction with the first aspect, in one possible implementation, the first motherboard and the second motherboard may be the same motherboard or different motherboards.

[0017] In a second aspect, an electronic device is provided, comprising a circuit system integrating a touch controller and an antenna as described in the first aspect.

[0018] In conjunction with the first aspect, in one possible implementation, the electronic device is smart glasses; wherein, one temple of the smart glasses is provided with a circuit system integrating a touch controller and an antenna as described in the first aspect.

[0019] This application achieves the following technical effects: By providing a circuit system and electronic device integrating a touch controller and an antenna, the system includes a first motherboard, a second motherboard, and an antenna; the first motherboard includes a radio frequency module, a first series capacitor, and a first matching circuit; the second motherboard includes a touch controller and an LC low-pass filter circuit; one end of the first series capacitor is connected to the radio frequency module, and the other end is connected to the first matching circuit, the other end of the first matching circuit is connected to the antenna; one end of the LC low-pass filter circuit is connected to the touch controller, and the other end is connected to the antenna; wherein, the first matching circuit is used to match the impedance of the radio frequency module with the impedance of the antenna, the LC low-pass filter circuit is used to block high-frequency signals from the radio frequency module that are higher than a first preset frequency from entering the touch controller, and the first series capacitor is used to block low-frequency signals generated by the touch controller that are lower than a second preset frequency. By configuring corresponding filter circuits, series capacitors, and matching circuits between the radio frequency module, the touch controller, and the antenna, it is ensured that the radio frequency module, the touch controller, and the antenna can still work together without interference even when tightly integrated. Attached Figure Description

[0020] Figure 1 A schematic diagram of a circuit system integrating a touch controller and an antenna, provided for an embodiment of this application; Figure 2 A schematic diagram of another integrated touch controller and antenna circuit system provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0021] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0022] The technical solution of this application is applicable to the field of electronic device technology, and particularly to electronic devices, which are preferably miniaturized and thin electronic devices, including but not limited to smart glasses, smart rings, etc. The electronic device includes the circuit system with integrated touch controller and antenna shown in this application.

[0023] The following is a detailed description of a circuit system integrating a touch controller and an antenna provided in this application.

[0024] like Figure 1As shown, this embodiment provides a circuit system integrating a touch controller and an antenna. The integrated touch controller and antenna circuit system 10 includes: a first motherboard 100, a second motherboard 102, and an antenna 101. The first motherboard 100 includes at least a radio frequency module 1001, a first series capacitor 1003, and a first matching circuit 1002. The second motherboard 102 includes a touch controller 1021 and a first series capacitor 1022.

[0025] In one possible design, the first motherboard 100 or the second motherboard 102 may also include highly integrated system-on-a-chip, memory, power management unit and other components, and this application does not impose any restrictions on this.

[0026] The first matching circuit 1002 is an electronic network used to achieve impedance matching. The structure of the first matching circuit 1002 can be L-shaped, π-shaped, T-shaped, etc. The first matching circuit 1002 is used to ensure that the impedance of the radio frequency module 1001 matches the impedance of the antenna 101, thereby maximizing the signal power transmission efficiency and reducing signal reflection and energy loss during transmission.

[0027] In one feasible implementation, the first matching circuit 1002 can ensure that the impedance of the RF module 1001 matches the impedance of the antenna 101 by precisely configuring the component values ​​of the inductor and / or capacitor in the first matching circuit 1002, transforming the complex impedance presented by the antenna 101 at the operating frequency point or operating frequency band of the antenna 101 into a load impedance that is conjugate matched with the output impedance of the RF module 1001.

[0028] For example, the first matching circuit 1002 is implemented using an L-shaped network, such as consisting of a first inductor and a first capacitor connected in series. If the measured impedance of the antenna at the 2.4GHz operating frequency is (25 + j30) ohms and the output impedance of the RF module is 50 ohms, then through simulation software, the first inductor in the first matching circuit 1002 can be set to 4.7 nanohenries (nH) and the first capacitor to 1.5 picofarads (pF). This combination of parameters can effectively transform the impedance of the aforementioned antenna at the 2.4GHz frequency to close to 50 ohms, thereby ensuring that the impedance of the RF module 1001 matches the impedance of the antenna 101.

[0029] For example, the first matching circuit 1002 can be implemented using a π-type network. For instance, the first matching circuit 1002 is composed of a first parallel capacitor, a second inductor, and a second parallel capacitor connected sequentially. If the output impedance of the RF module 1001 is 50 ohms, and the antenna operates in the 2.4GHz to 2.5GHz frequency band with significant impedance variations, simulation software can be used to calculate and set the first parallel capacitor to 1.0 picofarads (pF), the second inductor to 3.3 nanohenries (nH), and the second parallel capacitor to 2.2 picofarads (pF). This parameter combination can stably transform the impedance of the antenna 101 to approximately 50 ohms throughout the entire operating frequency band of the antenna, thereby ensuring that the impedance of the RF module 1001 matches the impedance of the antenna 101. Using this π-type network provides better broadband matching compared to an L-type network. The LC low-pass filter circuit 1022 is a passive filter composed of an inductor (L) and a capacitor (C) connected in series between the touch controller 1021 and the antenna 101. The LC low-pass filter circuit 1022 is used to block high-frequency signals from the radio frequency module 1001 that are higher than a first preset frequency from entering the touch controller 1021.

[0030] It should be noted that the first preset frequency refers to a frequency value pre-set according to the circuit system 10 of the integrated touch controller and antenna. For high-frequency signals generated by the RF module 1001 above the first preset frequency, the LC low-pass filter circuit 1022 will block them. For example, the first preset frequency can be pre-set according to the frequency range of the RF signal generated by the RF module 1001. For instance, if the frequency range of the RF signal generated by the RF module 1001 is 2.4GHz to 2.5GHz, then the first preset frequency can be set to 2.4GHz.

[0031] In one possible design, the capacitance value of the LC low-pass filter circuit 1022 is determined based on the frequency value of the RF module 1001 and the capacitance range of the LC low-pass filter circuit 1022 itself, as well as the corresponding parasitic parameters.

[0032] Specifically, when designing the capacitance value of the LC low-pass filter circuit 1022, the center operating frequency of the touch controller 1021 and the target capacitive reactance of the LC low-pass filter circuit 1022 can be determined first. Then, the theoretical reference value of the capacitance value can be estimated according to the following formula: f = 1 / (2π×C×Xc) Where f is the center operating frequency of the touch controller output signal, C is the capacitance value of the LC low-pass filter circuit, and Xc is the capacitive reactance.

[0033] Furthermore, after obtaining the theoretical reference value, the detailed specifications of the capacitor can be consulted. The S11 parameter (return loss) provided in the specifications can intuitively reflect the actual impedance characteristics and reflection of the capacitor at different frequencies. The S11 parameter reveals the impedance matching of the capacitor, and its matching quality is directly affected by the capacitor's parasitic parameters, mainly the equivalent series inductance and equivalent series resistance. These parasitic parameters cause the capacitor's impedance to change with frequency and generate a self-resonant frequency. At the self-resonant frequency, the capacitor's impedance is minimum, and the S11 performance is optimal; once the operating frequency exceeds the self-resonant frequency, the capacitor becomes inductive, the impedance increases, the S11 parameter deteriorates, and reflection intensifies. Therefore, when selecting a specific capacitor, its self-resonant frequency should be ensured to be higher than the circuit's operating frequency, and a model with an S11 parameter that meets the return loss requirements (e.g., S11 < -10dB or better) within the operating frequency band of the RF module should be selected, and it must also meet the capacitance range of the LC low-pass filter circuit.

[0034] As one possible implementation, the LC low-pass filter circuit 1022 can be connected to an antenna via a connector. For example, the connector can be a spring and / or an RF coaxial connector (such as an IPEX connector).

[0035] The first series capacitor 1003 refers to the capacitor element connected in series between the radio frequency module 1001 and the antenna 101, used to block low-frequency signals generated by the touch controller 1021 that are lower than the second preset frequency.

[0036] The working principle of the first series capacitor 2002 is as follows: the series capacitor can selectively conduct signals flowing through it. For radio frequency signals from the radio frequency module 1001 that are higher than the first preset frequency, the first series capacitor 2002 allows the radio frequency signals to pass through efficiently; while for low-frequency signals generated by the touch controller 1021 that are lower than the second preset frequency, the first series capacitor 2002 blocks the low-frequency signals from entering the radio frequency module, so that the low-frequency signals generated by the touch controller 1021 only propagate along the antenna path and do not flow back into the radio frequency module, thus forming unidirectional isolation on the signal path.

[0037] Since the radio frequency module 1001 may generate low-frequency signals, which are usually noise signals and easily interfere with the antenna 101, the first series capacitor 1003 is set and connected between the radio frequency module 1001 and the antenna 101 to block the low-frequency signals generated by the radio frequency module 1001 that are lower than the second preset frequency, while ensuring that high-frequency signals can pass normally. In conjunction with the LC low-pass filter circuit 1003, a bidirectional purification channel is established for the antenna, reducing the interference of useless signals on the antenna operation and improving the overall system performance.

[0038] It should be noted that the second preset frequency refers to a frequency value pre-set according to the integrated touch controller and antenna circuit system 10. For signals generated by the touch controller 1021 below the second preset frequency, the first series capacitor 1003 will block them. For example, the second preset frequency can be pre-set according to the frequency range of the touch signal of the touch controller. For instance, if the effective harmonic component of the touch signal of the touch controller 1021 is at most 1MHz, then the second preset frequency can be set to 1MHz.

[0039] As a feasible implementation, the value of the second preset frequency can be lower than the first preset frequency. This frequency relationship ensures that the LC low-pass filter circuit, the first series capacitor, and the second series capacitor can work together to form an effective signal isolation band between the signal band of the touch controller and the signal band of the radio frequency module, thereby achieving signal integrity when the two motherboards share an antenna.

[0040] For example, the second preset frequency of the touch controller is set to 1MHz, and the first preset frequency of the RF module is set to 2.4GHz. The frequency interval between the two allows the LC low-pass filter circuit to effectively suppress high-frequency RF noise, while the series capacitor blocks low-frequency touch signals, forming bidirectional isolation.

[0041] In one possible design, the capacitance value of the first series capacitor 1003 is determined based on the frequency value of the RF module 2001, the capacitance range of the first series capacitor 1003 itself, and the corresponding parasitic parameters. The determination method can be referenced in the preceding description of the capacitance determination method for the LC low-pass filter circuit 1022.

[0042] The connection relationship between the integrated touch controller and the antenna circuit system 10 is as follows: one end of the first series capacitor 1003 is connected to the radio frequency module 1001, and the other end is connected to the first matching circuit 1002. The other end of the first matching circuit 1002 is connected to the antenna 101; one end of the LC low-pass filter circuit 1022 is connected to the touch controller 1021, and the other end is connected to the antenna 101.

[0043] The working principle of the integrated touch controller and antenna circuit system 10 is as follows: Since the metal connecting the antenna 101 and the touch controller 1021 is made of the same material, conducted interference is easily generated during signal transmission. In addition, if the touch controller 1021, the radio frequency module 1001 and the antenna 101 are placed too close together in the layout, the electromagnetic waves emitted by the two when they are working will couple with each other through space, causing coupling interference. By incorporating a first matching circuit 1002 in the RF module 1001 and the antenna 101, the impedance of the RF module 1001 and the antenna 101 are matched, ensuring that the RF signal from the RF module 1001 can be efficiently transmitted to the antenna 101 and radiated out without excessive loss. By incorporating a first series capacitor 1003 between the RF module 1001 and the first matching circuit 1002, the touch signal generated by the touch controller 1021 is limited to propagating only along the path of the antenna 101, preventing it from flowing back into the RF module 1001. By incorporating an LC low-pass filter circuit 1022 between the touch controller 1021 and the antenna 101, the high-frequency signal from the RF module 1001 is blocked from entering the touch controller 1021. Through the coordinated design of the matching, filtering, and isolation circuits, mutual interference between the antenna 101, the touch controller 1021, and the touch controller 1021 is ensured.

[0044] In one possible design, antenna 101 is a radiator manufactured using any one of the following processes: flexible circuit board process, laser direct forming process, or metal stamping process.

[0045] In one possible design, the antenna 101 can be a monopole antenna.

[0046] It should be noted that this monopole antenna is a type of antenna that does not require grounding. Its antenna structure is relatively simple, typically consisting of a single radiator, and its resonant length can be one-quarter of the operating wavelength (λ / 4). This monopole antenna does not require the device's own flexible circuit board as a radiation ground plane; its radiation pattern mainly depends on the space around the antenna radiator, which makes its structural design more flexible.

[0047] In one possible design, the antenna 101 can also be a grounded antenna, including but not limited to any one or more of the following: PIFA antenna (Planar Inverted-F Antenna), LOOP antenna (Loop Antenna), and IFA antenna (Inverted-F Antenna).

[0048] When the antenna 101 is a grounded antenna, it includes an antenna feed pin and an antenna ground pin. The antenna feed pin is responsible for connecting to the radio frequency signal source, while the antenna ground pin is connected to the ground plane.

[0049] In one possible design, the maximum capacitance of the touch controller is 100pF. Those skilled in the art will understand that the maximum capacitance of touch controllers from different manufacturers may vary, and this application does not impose any limitations on this.

[0050] In one possible design, the first motherboard 100 and the second motherboard 102 may be the same motherboard or different motherboards.

[0051] When the first motherboard 100 and the second motherboard 102 are the same motherboard, that is, the radio frequency module 1001 and the touch controller 1021 are configured on the same motherboard, the integration level of the circuit system can be further improved and the size of the circuit system can be reduced.

[0052] As can be seen, in the embodiment shown in this application, the integrated touch controller and antenna circuit system includes a first motherboard, a second motherboard, and an antenna. The first motherboard includes a radio frequency module, a first series capacitor, and a first matching circuit. The second motherboard includes a touch controller and an LC low-pass filter circuit. One end of the first series capacitor is connected to the radio frequency module, and the other end is connected to the first matching circuit. The other end of the first matching circuit is connected to the antenna. One end of the LC low-pass filter circuit is connected to the touch controller, and the other end is connected to the antenna. The first matching circuit is used to match the impedance of the radio frequency module with the impedance of the antenna. The LC low-pass filter circuit is used to block high-frequency signals from the radio frequency module that are higher than a first preset frequency from entering the touch controller. The first series capacitor is used to block low-frequency signals generated by the touch controller that are lower than a second preset frequency. By configuring corresponding filter circuits, series capacitors, and matching circuits between the radio frequency module, the touch controller, and the antenna, it is ensured that the radio frequency module, the touch controller, and the antenna can still work together without interference even when tightly integrated.

[0053] Please refer to the following: Figure 2 This is a schematic diagram of another integrated touch controller and antenna circuit system provided in this application. Figure 2 The integrated touch controller and antenna circuit system 20 shown includes: a first motherboard 200, an antenna 201, and a second motherboard 202. Wherein: The first motherboard 200 includes an RF module 2001, a first series capacitor 2002, a first matching circuit 2003, and a second matching circuit 2006. The first motherboard 200 is equipped with a ground point 2004.

[0054] The second motherboard 202 includes a touch controller 2021 and an LC low-pass filter circuit 2022.

[0055] Antenna 201 includes an antenna ground pin 2011 and an antenna feed pin 2012. In some feasible embodiments, Figure 2The antenna 2011 shown is an antenna that needs to be grounded and may include a PIFA antenna and / or a LOOP antenna.

[0056] Figure 2 The connection relationship of the integrated touch controller and antenna circuit system 20 shown is as follows: one end of the first series capacitor 2002 is connected to the radio frequency module 2001, and the other end is connected to the first matching circuit 2003. The other end of the first matching circuit 2003 is connected to the antenna feed pin 2012. One end of the second matching circuit 2006 is connected to the ground point 2004, and the other end is connected to the antenna ground pin 2011. One end of the LC low-pass filter circuit 2022 is connected to the touch controller 2021, and the other end is connected to the antenna feed pin 2012.

[0057] It should be noted that the second matching circuit 2006 refers to a network composed of passive components such as capacitors and inductors connected between the antenna ground pin 2011 and the grounding point 2004.

[0058] The working principle of the second matching circuit 2006 is as follows: Since there may be common ground interference between the antenna ground pin 2011 and the grounding point 2004 of the first motherboard, which could interfere with the quality of the communication signal, the second matching circuit 2006 is set between the antenna ground pin 2011 and the grounding point 2004 to match the path impedance from the antenna ground pin 2011 to the grounding point. This reduces the energy loss due to high-frequency signal reflection within the circuit caused by impedance mismatch, ensuring that the RF signal of the RF module 2001 can smoothly pass through the grounding loop. Simultaneously, it can work in conjunction with the first matching circuit 202 to ensure that the RF signal is transmitted from the RF module 2001 to the antenna 201 and radiated out most effectively.

[0059] As one feasible implementation, the second matching circuit 2006 can employ a single series inductor, a single series capacitor, a single parallel capacitor, a parallel inductor, an L-shaped network, a π-shaped network, a T-shaped network, or a matching topology composed of more components. The choice of topology depends on the impedance characteristics of the antenna ground loop: if the antenna ground loop only has high inductive reactance, a series capacitor can be selected; if the antenna ground loop impedance is capacitive, a series inductor can be selected; if the ground loop impedance is complex (containing both resistive and reactive components) and low impedance needs to be achieved over a wide bandwidth, then complex networks with multiple components and multiple degrees of freedom, such as L-shaped, π-shaped, or T-shaped networks, can be used for precise impedance transformation and tuning.

[0060] The second matching circuit 2006 can ensure that the path impedance from the antenna ground pin 2011 to the ground point 2004 is matched by configuring the component values ​​of the inductor and / or capacitor in the second matching circuit 2006 to adjust the complex impedance presented by the antenna ground loop at the operating frequency to a stable state close to zero impedance, thereby providing a high-quality grounding path for the radio frequency signal.

[0061] For example, the second matching circuit 2006 is implemented using an L-shaped network, meaning it consists of a capacitor and an inductor connected in series. If the measured impedance of the antenna ground loop at 2.4 GHz is (0.8 + j18) ohms, and it is desired to adjust it to a near-ideal low impedance state close to zero impedance, simulation software can be used to calculate and set the parallel capacitor in the second matching circuit 2006 to 1.5 picofarads (pF) and the series inductor to 2.7 nanohenries (nH). This parameter combination can effectively transform the aforementioned ground loop impedance at 2.4 GHz to close to (0.8 + j0.2) ohms, thereby establishing a stable low-impedance grounding path for the radio frequency signal.

[0062] In one embodiment, the first motherboard 200 may further include a second series capacitor 2005. The second series capacitor 2005 is connected between the ground point 2004 and the second matching circuit 2006 to provide a low-impedance grounding loop for the radio frequency signal of the antenna within a preset frequency range and to block DC signals to prevent the antenna from short-circuiting.

[0063] The second series circuit 2005 works as follows: Since the radio frequency module 2001 on the first motherboard 200 generates low-frequency signals, these signals may crosstalk to the antenna 2011 through the grounding point, thus interfering with the antenna 2011. By placing the second series capacitor 2005 between the grounding point and the second matching circuit 2006, a low-impedance grounding loop can be provided for the radio frequency signals of the antenna within a preset frequency range, and signals below the second preset frequency of the touch controller can be blocked, preventing the touch controller signal from short-circuiting to ground.

[0064] In one possible design, the capacitance value of the second series capacitor 2005 is determined based on the frequency value of the RF module 2001 and the parasitic parameters corresponding to the second series capacitor 2005.

[0065] In one possible design, the capacitance value of the second series capacitor 2005 ranges from 27pF to 80pF.

[0066] Specifically, when designing the capacitance value of the second series capacitor 2005, the center operating frequency of the RF module 2001 and the target capacitive reactance of the second series capacitor 2005 can be determined, and then the theoretical reference value of the capacitance value can be estimated according to the following formula: f = 1 / (2π×C×Xc) Where f is the center operating frequency of the RF module 2001, C is the capacitance value of the second series capacitor 2005, and Xc is the capacitive reactance.

[0067] Furthermore, after obtaining the theoretical reference value, the detailed datasheet of the capacitor can be consulted. The S11 parameter (return loss), especially the parasitic parameters, provided in the datasheet determine the capacitance value of the second series capacitor 2005.

[0068] In one possible design, the second series capacitor 2005 and the first series capacitor 2002 can have the same model and capacitance value.

[0069] As can be seen from the embodiments shown in this application, when the antenna is a grounded antenna, in Figure 1 Based on the illustrated embodiment, by adding a second matching circuit and a second series capacitor, one end of the second matching circuit is connected to the antenna ground pin and the other end is connected to the ground point of the first motherboard. One end of the second series capacitor is connected to the second matching circuit and the other end is connected to the ground point of the first motherboard. This optimizes the impedance of the grounding path and, through the characteristics of the second series capacitor, blocks the portion of low-frequency signals from the second motherboard that are coupled to the antenna through the ground path, suppressing common ground interference. This further improves the anti-interference level between the antenna and the touch controller and RF module, and enhances the overall performance optimization and stability of the integrated touch controller and antenna circuit system.

[0070] Please refer to the following: Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 3 The electronic device 01 shown includes a circuit system that integrates a touch controller and an antenna.

[0071] In one possible design, the electronic device 01 can be a miniaturized and thin electronic device, such as a wearable device, specifically smart glasses, a smart ring, etc. The electronic device 01 is equipped with a circuit system integrating a touch controller and an antenna. The structure, connection relationships, and main functions of this integrated touch controller and antenna circuit system can be found in the foregoing. Figure 1 and Figure 2 The corresponding descriptions of the embodiments shown are not repeated here.

[0072] In one possible design, when the electronic device is smart glasses, the circuitry integrating the touch controller and antenna is configured in one temple of the smart glasses.

[0073] For example, the integrated touch controller and antenna circuitry can be configured on the outer side of one temple of the smart glasses. Users can control functions such as volume or page turning by sliding the touch controller area on the outer side of the temple.

[0074] For example, the touch controller can be a pressure sensor. When the touch controller is a pressure sensor, the integrated touch controller and antenna circuitry can be configured on the inside of one temple of the smart glasses to detect whether the glasses are being worn (when the pressure sensor is triggered, it is considered that the glasses are being worn).

[0075] In summary, the integrated touch controller and antenna circuit system and electronic device of this application, by setting a first matching circuit in the integrated touch controller and antenna circuit system to match the output impedance of the RF module with the input impedance of the antenna, setting an LC low-pass filter circuit to block high-frequency signals of the RF module higher than the first preset frequency from entering the touch controller, and setting a first series capacitor to establish a bidirectional purification channel between the RF signal of the antenna and the signal of the touch controller, ensures that the touch controller, RF module and antenna can still work together without interference even when tightly integrated.

[0076] The above-disclosed embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of this application. Therefore, any equivalent variations made in accordance with the claims of this application shall still fall within the scope of this application.

Claims

1. A circuit system integrating a touch controller and an antenna, characterized in that, Including the first motherboard, the second motherboard, and the antenna; The first motherboard includes an RF module, a first series capacitor, and a first matching circuit; The second motherboard includes a touch controller and an LC low-pass filter circuit; One end of the first series capacitor is connected to the radio frequency module, and the other end is connected to the first matching circuit. The other end of the first matching circuit is connected to the antenna. One end of the LC low-pass filter circuit is connected to the touch controller, and the other end is connected to the antenna; The first matching circuit is used to match the impedance of the radio frequency module with the impedance of the antenna, the LC low-pass filter circuit is used to block high-frequency signals from the radio frequency module that are higher than a first preset frequency from entering the touch controller, and the first series capacitor is used to block low-frequency signals generated by the touch controller that are lower than a second preset frequency.

2. The circuit system integrating a touch controller and an antenna according to claim 1, characterized in that, The antenna includes an antenna ground pin and an antenna feed pin, and the other end of the first matching circuit is connected to the antenna feed pin; The first motherboard also includes: a second matching circuit; One end of the second matching circuit is connected to the antenna ground pin, and the other end is connected to the ground point of the first motherboard. The second matching circuit is used to match the path impedance from the antenna ground pin to the ground point of the first motherboard.

3. The circuit system integrating a touch controller and an antenna according to claim 2, characterized in that, The first motherboard also includes: a second series capacitor; One end of the second series capacitor is connected to the ground pin of the antenna, and the other end is connected to the grounding point of the first motherboard. The second series capacitor is used to provide a grounding path for the radio frequency signal of the antenna within a preset frequency range, and to block signals below the second preset frequency of the touch controller, so as to prevent the signal of the touch controller from being short-circuited to ground.

4. The circuit system integrating a touch controller and an antenna according to claim 3, characterized in that, The capacitance values ​​of the first series capacitor and the second series capacitor are determined based on the frequency value of the radio frequency module, the capacitance value range of the first series capacitor and the second series capacitor, and the corresponding parasitic parameters.

5. The circuit system integrating a touch controller and an antenna according to claim 2, characterized in that, The antenna is a grounded antenna, which includes any one or more of the following: PIFA antenna, LOOP antenna, and IFA antenna.

6. The circuit system integrating a touch controller and an antenna according to claim 1, characterized in that, The antenna is a monopole antenna.

7. The circuit system integrating a touch controller and an antenna according to claim 1, characterized in that, The antenna is a radiator manufactured using any one of the following processes: flexible circuit board process, laser direct forming process, or metal stamping process.

8. The circuit system integrating a touch controller and an antenna according to claim 1, characterized in that, The first motherboard and the second motherboard are the same motherboard.

9. An electronic device, characterized in that, The electronic device includes a circuit system with an integrated touch controller and antenna as described in any one of claims 1 to 8.

10. The electronic device as claimed in claim 9, characterized in that, The electronic device is a smart glasses; wherein, at least one temple of the smart glasses is provided with a circuit system integrating a touch controller and an antenna as described in any one of claims 1 to 8.

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