High-frequency filter

Abstract

High-frequency filters, comprehensive: a first capacitive element comprising a first terminal and a second terminal; a second capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the second capacitive element is coupled to the second terminal of the first capacitive element; a third capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the third capacitive element is coupled to the second terminal of the second capacitive element; a fourth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the fourth capacitive element is coupled to the first terminal of the second capacitive element; a fifth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the fifth capacitive element is coupled to the second terminal of the second capacitive element; and a sixth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the sixth capacitive element is coupled to the second terminal of the third capacitive element; wherein the second connection of the fourth capacitive element, the second connection of the fifth capacitive element and the second connection of the sixth capacitive element are coupled to a first node.

Description

TECHNICAL AREA

[0001] The present disclosure relates to a high-frequency filter, in particular a high-frequency filter used for bandpass filtering. BACKGROUND

[0002] In newer communication systems, the n77 band (3300 MHz–4200 MHz) is frequently used for 5G testing and development due to its broad applicability and advantages. A critical goal of the 5G New Radio (NR) standard is to achieve wider bandwidths by combining continuous spectrum to provide high communication capacity for high data throughput. With a center frequency around 3.7 GHz, the n77 band has become a widely available option. Filters designed for this band are required to effectively allow signals to pass within the desired frequency range while attenuating unwanted signals outside the n77 band. Technologies such as film bulk acoustic wave resonators (FBARs) and low-temperature cofired ceramics (LTCCs) can be used for this purpose. However, difficulties associated with cost-effectiveness and integration complexity can pose challenges.Consequently, there is a need for high-performance, cost-effective radio frequency filters optimized for the n77 band. SUMMARY

[0003] A high-frequency filter according to the invention is defined in independent claim 1. The dependent claims define preferred embodiments thereof. One embodiment provides a high-frequency filter comprising a first capacitive element up to a sixth capacitive element, each comprising a first terminal and a second terminal. The first terminal of the second capacitive element is coupled to the second terminal of the first capacitive element. The first terminal of the third capacitive element is coupled to the second terminal of the second capacitive element. The first terminal of the fourth capacitive element is coupled to the first terminal of the second capacitive element. The first terminal of the fifth capacitive element is coupled to the second terminal of the second capacitive element.The first terminal of the sixth capacitive element is coupled to the second terminal of the third capacitive element. The second terminal of the fourth capacitive element, the second terminal of the fifth capacitive element, and the second terminal of the sixth capacitive element are coupled to a first node. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a circuit diagram of a high-frequency filter according to an embodiment of the present disclosure. Fig. Figure 2 is a diagram showing a frequency response of the high-frequency filter according to an embodiment of the present disclosure. Fig. Figure 3 is a schematic diagram representing the first substrate of the high-frequency filter according to an embodiment of the present disclosure. Fig. Figure 4 is a schematic diagram of the second substrate of the high-frequency filter according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0004] Exemplary embodiments are described in detail below with reference to the accompanying drawings, so that they can be easily implemented by a person skilled in the art. The inventive concept can be implemented in various forms without being limited to the exemplary embodiments presented herein. Descriptions of well-known parts have been omitted for clarity, and identical reference numerals refer to the same elements throughout.

[0005] The present invention can be understood with reference to the following detailed description in conjunction with the accompanying drawings. It should be noted that, for the sake of simplicity, the drawings may only depict a portion of the elements / steps and may not be drawn to scale. Each figure illustrates the general characteristics of the elements, methods, structures, and / or materials used in a specific embodiment. Furthermore, the number and size of each feature in the drawings are for illustrative purposes only and are not intended to limit the scope of the present invention. For example, for the sake of clarity, the size of each element, area, and / or structure may be reduced or increased, and / or its position may be changed. Directional terms used herein, such as "top," "bottom," "front," "back," "left," "right," "inside," "outside," etc., are for illustrative purposes only.are used to describe general relative positions and are not intended to limit the scope of the present invention.

[0006] The person skilled in the art will understand that in the industry, different names or symbols may refer to the same element / step. The present disclosure does not intend to differentiate between elements / steps that have the same function but different names. When a component is described in the present disclosure as being selectively or optionally configured, this means that the component can be configured or removed as needed, and all such configurations fall within the scope of this disclosure.

[0007] In the following description, "capacitive elements" can include capacitors, acoustic wave devices, and other components with capacitive properties. For example, capacitors can include metal-insulator-metal (MIM) capacitors, metal-oxide-metal (MOM) capacitors, metal-oxide-semiconductor (MOS) capacitors, and the like. Furthermore, the two metal electrodes of the capacitor can be stacked vertically or horizontally, and the present disclosure is not particularly limited. Additionally, acoustic wave devices can include, for example, surface acoustic wave (SAW) devices, bulk acoustic wave (BAW) devices, and the like, such as thin-film bulk acoustic resonators (FBARs).

[0008] In the following description, "inductive elements" can include metal windings, metal bond wires, metal vias, and other elements with inductive properties. For example, inductive elements can be planar or three-dimensional, and the metals can be distributed on the same metal layer or on different metal layers.

[0009] In the following description, “essentially the same” may include situations where the difference between the values ​​of the two elements is less than 10%, preferably less than 5%. The above description is for illustrative purposes only and is not intended to limit the present disclosure.

[0010] Fig. Figure 1 is a circuit diagram of a high-frequency filter 100 according to an embodiment of the present disclosure. As shown, the high-frequency (HF) filter 100 in one embodiment may include a first transmit-receiver terminal RF1, a second transmit-receiver terminal RF2, and various elements coupled between them. The first transmit-receiver terminal RF1 may be configured to receive an RF input signal, and the second transmit-receiver terminal RF2 may be configured to transmit an RF output signal. The RF signal is sent from the first transmit-receiver terminal RF1 to the second transmit-receiver terminal RF2 and filtered by the RF filter 100, leaving behind an RF signal in a specific frequency band, such as band n77 (3300 MHz–4200 MHz). However, the present disclosure is not limited thereto.In other embodiments, the second transceiver port RF2 can be configured to receive an RF input signal, and the first transceiver port RF1 can be configured to transmit an RF output signal. Furthermore, the RF filter 100 can include a series path and at least one parallel path coupled between the first transceiver port RF1 and the second transceiver port RF2.

[0011] As shown, the series path of the RF filter 100 can include a first capacitive element C1, a second capacitive element C2, and a third capacitive element C3, each comprising a first terminal and a second terminal. The first capacitive element C1, the second capacitive element C2, and the third capacitive element C3 can be sequentially connected in series between the first transmit-receiver terminal RF1 and the second transmit-receiver terminal RF2. Specifically, the first terminal of the first capacitive element C1 can be connected to the first transmit-receiver terminal RF1. The first terminal of the second capacitive element C2 can be connected to the second terminal of the first capacitive element C1. The first terminal of the third capacitive element C3 can be connected to the second terminal of the second capacitive element C2.The second terminal of the third capacitive element C3 can be coupled to the second transmitter-receiver terminal RF2.

[0012] Furthermore, parallel paths of the RF filter 100 can include a fourth capacitive element C4, a fifth capacitive element C5, and a sixth capacitive element C6, each comprising a first terminal and a second terminal. Specifically, a first terminal of the fourth capacitive element C4 can be coupled to a first terminal of the second capacitive element C2, and a second terminal of the fourth capacitive element C4 can be coupled to a first node N1. A first terminal of the fifth capacitive element C5 can be coupled to a second terminal of the second capacitive element C2, and a second terminal of the fifth capacitive element C5 can be coupled to the first node N1.A first terminal of the sixth capacitive element C6 can be coupled to a second terminal of the third capacitive element C3, and a second terminal of the sixth capacitive element C6 can be coupled to the first node N1. In other words, the second terminal of the fourth capacitive element C4, the second terminal of the fifth capacitive element C5, and the second terminal of the sixth capacitive element C6 can be coupled to each other and together with the first node N1. In one embodiment, the first node N1 can be coupled to a reference voltage terminal, such as ground.

[0013] In one embodiment, the RF filter 100 can further include a parasitic inductance LP, which may have a first terminal and a second terminal. The parasitic inductance LP can be coupled between the first node N1 and the reference voltage terminal, wherein the first terminal of the parasitic inductance LP is coupled to the first node N1 and the second terminal is coupled to the reference voltage terminal. In another embodiment, the first node N1 can also be directly coupled to the reference voltage terminal, i.e., the parasitic inductance LP is omitted.

[0014] In another embodiment, the parallel paths of the RF filter 100 can further include a first inductive element L1, which may have a first terminal and a second terminal. The first terminal can be coupled to the second transceiver terminal RF2, and the second terminal can be coupled to the reference voltage terminal. In this case, the first inductive element L1 can provide various advantages, such as improved frequency response at the low-frequency outer band of the RF filter 100 and protection against electrostatic discharge (ESD).

[0015] In one embodiment, the series path of the RF filter 100 can further include a seventh capacitive element C7, an eighth capacitive element C8, and a second inductive element L2, each of which can have a first terminal and a second terminal. For example, the seventh capacitive element C7 can be coupled between the first transceiver terminal RF1 and the first capacitive element C1. The first terminal of the seventh capacitive element C7 can be coupled to the first transceiver terminal RF1, and the second terminal can be coupled to the first terminal of the first capacitive element C1. The eighth capacitive element C8 and the second inductive element L2 can be coupled in series, and the series connection comprising the eighth capacitive element C8 and the second inductive element L2 can be coupled in parallel with the seventh capacitive element C7.For example, the first terminal of the second inductive element L2 can be connected to the first terminal of the seventh capacitive element C7, the first terminal of the eighth capacitive element C8 can be connected to the second terminal of the second inductive element L2, and the second terminal of the eighth capacitive element C8 can be connected to the second terminal of the seventh capacitive element C7. In other embodiments, the connection sequence of the second inductive element L2 and the eighth capacitive element C8 can be different.

[0016] In one embodiment, the RF filter 100 may additionally include an eleventh capacitive element C11 and a twelfth capacitive element C12, each of which may have a first terminal and a second terminal. The first terminal of the eleventh capacitive element C11 may be coupled to the first terminal of the seventh capacitive element C7, and the second terminal of the eleventh capacitive element C11 may be coupled to the reference voltage terminal. The first terminal of the twelfth capacitive element C12 may be coupled to the second terminal of the seventh capacitive element C7, and the second terminal of the twelfth capacitive element C12 may be coupled to the reference voltage terminal.

[0017] In one embodiment, the parallel paths of the RF filter 100 can further include a ninth capacitive element C9, a third inductive element L3, a tenth capacitive element C10, and a fourth inductive element L4, each of which can have a first terminal and a second terminal. The first terminal of the ninth capacitive element C9 can be coupled to the second terminal of the first capacitive element C1. The first terminal of the third inductive element L3 can be coupled to the second terminal of the ninth capacitive element C9, and the second terminal of the third inductive element L3 can be coupled to the reference voltage terminal. For example, the first terminal of the ninth capacitive element C9 can be coupled between the first capacitive element C1 and the second capacitive element C2.Furthermore, the first terminal of the tenth capacitive element C10 can be connected to the second terminal of the second capacitive element C2. The first terminal of the fourth inductive element L4 can be connected to the second terminal of the tenth capacitive element C10, and the second terminal of the fourth inductive element L4 can be connected to the reference voltage terminal. For example, the first terminal of the tenth capacitive element C10 can be connected between the second capacitive element C2 and the third capacitive element C3.

[0018] Fig. Figure 2 is a diagram showing the frequency response of a high-frequency filter according to an embodiment of the present disclosure. The RF filter can be used, for example, for band n77 of 5G, i.e., 3300 MHz to 4200 MHz.

[0019] As shown, the solid line S1 represents a curve of the transfer parameter of the RF filter 100, and the dashed line S2 represents a curve of the reflection parameter of the RF filter 100. For example, the index m1 can correspond to a first frequency f1, e.g., 3300 MHz, and the index m2 can correspond to a second frequency f2, e.g., 4200 MHz, with a center frequency fc being essentially 3750 MHz (the average of the first frequency f1 and the second frequency f2). The range between the index m1 and the index m2 corresponds essentially to the band n77. In some embodiments, the passband of the RF filter 100 can be a frequency band between the first frequency f1 and the second frequency f2.As shown by the solid line S1, the transmission parameter of RF filter 100 approaches 0 dB between indices m1 and m2, indicating that the RF signal can pass through RF filter 100 between the first frequency f1 and the second frequency f2 with essentially no loss. Furthermore, as shown by the dashed line S2, the reflection parameter of RF filter 100 is at a low level (e.g., less than -20 dB) between indices m1 and m2, indicating that when the RF signal is input to RF filter 100 between the first frequency f1 and the second frequency f2, a relatively small portion of the RF signal is reflected.

[0020] Furthermore, the index m3 can correspond to the third frequency f3, e.g., 2690 MHz, and the index m4 can correspond to the fourth frequency f4, e.g., 5150 MHz. In some embodiments, the third frequency f3 and the fourth frequency f4 may be outside the passband. As shown by the solid line S1, for indices m3 and m4, the transfer parameters of the RF filter 100 are both less than -20 dB, indicating that the RF signals at the third frequency f3 and the fourth frequency f4 are essentially suppressed.

[0021] The reflection parameters (as shown by the dashed line S2) at frequencies between the first frequency f1 and the second frequency f2 are less than -20 dB, indicating that a well-matched impedance for the RF filter 100 is achieved between the first frequency f1 (3300 MHz) and the second frequency f2 (4200 MHz). Therefore, RF signals propagating to the second transmit / receive port RF2 (or the first transmit / receive port RF1) are subject to less reflection. The passband of the RF filter 100 can, for example, be between 3300 MHz and 4200 MHz, which is the frequency range that can be passed through the RF filter 100 with significantly less reflection loss.As shown by the solid line S1, the transmission parameters to the left of index m3 (2690 MHz) are less than -20 dB, and the transmission parameters to the right of index m4 (5150 MHz) are also less than -20 dB, indicating that the low-frequency and high-frequency out-of-band signals are effectively suppressed by the RF filter 100. In one embodiment, the third frequency f3 can be lower than the first frequency f1, the first frequency f1 can be lower than the second frequency f2, and the second frequency f2 can be lower than the fourth frequency f4.

[0022] Fig. Figure 2 shows four zeros: zero1, zero2, zero3, and zero4. For example, the frequencies of the first zero1 and the second zero2 can be lower than the first frequency f1 and further lower than the third frequency f3, for example, lower than 2690 MHz. That is, the first zero1 and the second zero2 can be located to the left of the passband, i.e., in the low-frequency outer band. Furthermore, the frequency of the second zero2 can be higher than the frequency of the first zero1. In some embodiments, the ratio of the frequency of the first zero1 relative to the center frequency fc can be, for example, in the range of 0 to 0.88. For example, the frequency of the first zero1 can be 2160 MHz, and its ratio relative to the center frequency fc (approximately 3750 MHz) is 0.576. The ratio of the frequency of the second zero2 relative to the center frequency fc can also be, for example, in the range of 0 to 0.88.For example, the frequency of the second zero zero2 can be 2430 MHz and its ratio relative to the center frequency fc is 0.648.

[0023] Additionally, the frequencies of the third zero-zero3 and the fourth zero-zero4 can be higher than the second frequency f2 and can furthermore be higher than the fourth frequency f4, for example, higher than 5150 MHz. That is, the third zero-zero3 and the fourth zero-zero4 can be located to the right of the passband, i.e., the high-frequency outer band. Furthermore, the frequency of the fourth zero-zero4 can be higher than the frequency of the third zero-zero3. In some embodiments, the ratio of the frequency of the third zero-zero3 relative to the center frequency fc can be, for example, greater than 1.12. For example, the frequency of the third zero-zero3 can be 5730 MHz and its ratio relative to the center frequency fc can be 1.528. The frequency of the fourth zero-zero4 relative to the center frequency fc can also be, for example, greater than 1.12.For example, the frequency of the fourth zero, zero4, can be 8951 MHz, and its ratio relative to the center frequency, fc, can be 2.387. It should be noted that the positions of the zeros mentioned above are for illustrative purposes only and are not intended to limit the present disclosure. In other embodiments, for example, the frequency of the fourth zero, zero4, can be approximately 10 GHz.

[0024] With reference to Fig. 1 and Fig. In RF filter 100, the ninth capacitive element C9 and the third inductive element L3 can correspond to the first zero zero1. The tenth capacitive element C10 and the fourth inductive element L4 can correspond to the second zero zero2. The second inductive element L2, the eighth capacitive element C8, and the seventh capacitive element C7 can correspond to the third zero zero3. The fourth capacitive element C4, the fifth capacitive element C5, the sixth capacitive element C6, and the parasitic inductance Lp can correspond to the fourth zero zero4. The parasitic inductance Lp can be generated, for example, by metal vias in a multilayer substrate or by solid metal conductors on the substrate.In some embodiments, different zero positions can be adjusted by changing parameters of their corresponding elements, and the parameters can be, for example, the capacitance, inductance, and coupling positions of the elements mentioned above.

[0025] In the embodiment described above, the RF filter 100 can suppress signals in the low-frequency outer band (e.g., frequencies below 2690 MHz) by generating the first zero zero1 and the second zero zero2, thereby avoiding interference resulting from signals in the low-frequency outer band (e.g., 4G signals). By generating the third zero zero3 and the fourth zero zero4, the RF filter 100 can suppress signals in the high-frequency outer band (e.g., frequencies above 5150 MHz), thereby avoiding interference resulting from signals in the high-frequency outer band (e.g., second harmonics). Therefore, RF signals in the low-frequency outer band (e.g., 4G signals) and the high-frequency outer band (e.g., second harmonic) are essentially suppressed, and the desired RF signal (3300 MHz–4200 MHz) can essentially pass through the RF filter 100, thus achieving an optimal bandpass filter for the n77 band.

[0026] Fig. Figure 3 is a schematic diagram representing the first substrate 300 of the high-frequency filter 100 according to one embodiment of the present disclosure. The first to twelfth capacitive elements C1-C12 can be arranged on the first substrate 300. In one embodiment, some capacitive elements (e.g., capacitive element C8) can have a relatively large capacitance, which can be implemented by connecting a plurality of capacitors in parallel. For example, the capacitive elements can be implemented as capacitors, such as metal-insulator-metal (MIM) capacitors.

[0027] In one embodiment, the first substrate 300 can be manufactured using an integrated passive device (IPD) process. For example, the dimensions of the first substrate 300 can be 1000 µm × 500 µm. Fig. 3 also represents a variety of compounds P1-P7.

[0028] Fig. Figure 4 is a schematic diagram of the second substrate 400 of the high-frequency filter 100 according to one embodiment of the present disclosure. The first to fourth inductive elements L1-L4 and the parasitic inductance LP can be arranged on the second substrate 400. In one embodiment, the second substrate 400 can be a multilayer substrate (e.g., a six-layer substrate). For example, the second substrate 400 can comprise at least two material layers. The second inductive element L2, the third inductive element L3, and the fourth inductive element L4 can be arranged in the first material layer. The first inductive element L1 can be arranged in the second material layer.Additionally, as described above, the parasitic inductance LP can be generated by metal through-holes in the multilayer substrate or by some bulk metal conductors on the substrate, and can be arranged in a single material layer or multiple material layers. As shown, when viewed in a direction perpendicular to the second substrate 400, the parasitic inductance LP can be located between the second inductive element L2 and the first inductive element L1. This configuration can help reduce the coupling between different transceiver terminals (e.g., the first transceiver terminal RF1 and the second transceiver terminal RF2), thereby essentially maintaining the outband suppression effect.In another embodiment, the first inductive element L1, the second inductive element L2, the third inductive element L3 or the fourth inductive element L4 can be three-dimensional inductors that can be arranged in several metal layers, but the present disclosure is not limited thereto.

[0029] With reference to Fig. 4. For example, when viewed from top to bottom in a direction perpendicular to the second substrate 400, if the first transmitter-receiver terminal RF1 acts as the input terminal and the second transmitter-receiver terminal RF2 acts as the output terminal, the current flows through the first inductive element L1, the second inductive element L2, the third inductive element L3, and the fourth inductive element L4 in a counterclockwise direction. If the first transmitter-receiver terminal RF1 acts as an output terminal and the second transmitter-receiver terminal RF2 acts as an input terminal, the current flows through the first inductive element L1, the third inductive element L3, and the fourth inductive element L4 in a counterclockwise direction, while the current flows through the second inductive element L2 in a clockwise direction.

[0030] In one embodiment, the second substrate 400 can be produced using a Land Grid Array (LGA) process. Fig. Figure 4 also shows the first transceiver connection RF1, the second transceiver connection RF2, and a variety of connections P1-P7. When the second substrate 400 is combined with the first substrate 300, the connections P1-P7 of the second substrate 400 can each be coupled with the connections P1-P7 of the first substrate 300.

[0031] In summary, the present disclosure provides an embodiment of a high-frequency filter 100, which can be implemented, for example, using a first substrate 300 and a second substrate 400. A plurality of capacitive elements and a plurality of inductive elements are provided in the high-frequency filter 100, thereby providing a bandpass filter suitable for the n77 band of 5G. This bandpass filter can effectively suppress signals in the low-frequency outer band (<2690 MHz) and / or signals in the high-frequency outer band (>5150 MHz). The size of the device and the manufacturing costs can also be reduced.

[0032] The person skilled in the art will readily recognize that numerous modifications and alterations to the apparatus and the method can be made while retaining the teachings of the invention. Accordingly, the above disclosure should be interpreted as being limited only by the scope and boundaries of the appended claims.

Claims

[1] High-frequency filters, comprising: a first capacitive element comprising a first terminal and a second terminal; a second capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the second capacitive element is coupled to the second terminal of the first capacitive element; a third capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the third capacitive element is coupled to the second terminal of the second capacitive element; a fourth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the fourth capacitive element is coupled to the first terminal of the second capacitive element; a fifth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the fifth capacitive element is coupled to the second terminal of the second capacitive element; and a sixth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the sixth capacitive element is coupled to the second terminal of the third capacitive element; wherein the second connection of the fourth capacitive element, the second connection of the fifth capacitive element and the second connection of the sixth capacitive element are coupled to a first node. [2] High-frequency filter according to claim 1, wherein the first capacitive element, the second capacitive element and the third capacitive element are sequentially coupled in series; and the first node is coupled to a reference voltage terminal. [3] High-frequency filter according to claim 1 or 2, further comprising: a first transceiver connection that is coupled to the first connection of the first capacitive element; a second transceiver terminal coupled to the second terminal of the third capacitive element; and a first inductive element comprising a first terminal and a second terminal, wherein the first terminal of the first inductive element is coupled to the second transceiver terminal and the second terminal of the first inductive element is coupled to the reference voltage terminal. [4] High-frequency filter according to claim 3, further comprising a seventh capacitive element coupled between the first transceiver connection and the first capacitive element. [5] High-frequency filter according to claim 4, further comprising: a second inductive element comprising a first terminal and a second terminal, wherein the first terminal of the second inductive element is coupled to the first transceiver terminal; and an eighth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the eighth capacitive element is coupled to the second terminal of the second inductive element and the second terminal of the eighth capacitive element is coupled to the second terminal of the seventh capacitive element. [6] High-frequency filter according to claim 5, further comprising: a ninth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the ninth capacitive element is coupled to the second terminal of the first capacitive element; and a third inductive element comprising a first terminal and a second terminal, wherein the first terminal of the third inductive element is coupled to the second terminal of the ninth capacitive element and the second terminal of the third inductive element is coupled to the reference voltage terminal. [7] High-frequency filter according to claim 6, further comprising: a tenth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the tenth capacitive element is coupled to the first terminal of the third capacitive element; and a fourth inductive element comprising a first terminal and a second terminal, wherein the first terminal of the fourth inductive element is coupled to the second terminal of the tenth capacitive element and the second terminal of the fourth inductive element is coupled to the reference voltage terminal. [8] High-frequency filter according to claim 7, wherein: In a frequency response of the high-frequency filter, the high-frequency filter has a passband between a first frequency and a second frequency, the first frequency is smaller than the second frequency, and a center frequency is an average of the first frequency and the second frequency; The ninth capacitive element and the third inductive element generate a first zero; The tenth capacitive element and the fourth inductive element generate a second zero; and a frequency of the second zero is higher than a frequency of the first zero. [9] High-frequency filter according to claim 8, wherein: the frequency of the second zero is lower than the first frequency. [10] High-frequency filter according to claim 8 or 9, wherein: The second inductive element, the eighth capacitive element, and the seventh capacitive element generate a third zero; The fourth capacitive element, the fifth capacitive element, and the sixth capacitive element produce a fourth zero; a frequency of the fourth zero is higher than a frequency of the third zero. [11] High-frequency filter according to claim 10, wherein: the frequency of the third zero is higher than the second frequency. [12] High-frequency filter according to any one of claims 8 to 11, wherein the ratio of the frequency of the first zero to the center frequency is substantially 0.

576. [13] High-frequency filter according to any one of claims 8 to 12, wherein the ratio of the frequency of the second zero to the center frequency is substantially 0.

648. [14] High-frequency filter according to claim 10 or one of claims 11 to 13 in direct or indirect dependence on claim 10, wherein the ratio of the frequency of the third zero to the center frequency is substantially 1.

528. [15] High-frequency filter according to claim 10 or 14 or one of claims 11 to 13 in direct or indirect dependence on claim 10, wherein the ratio of the frequency of the fourth zero to the center frequency is substantially 2.

387. [16] High-frequency filter according to any one of claims 7 to 15, further comprising: an eleventh capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the eleventh capacitive element is coupled to the first terminal of the seventh capacitive element and the second terminal of the eleventh capacitive element is coupled to the reference voltage terminal; and a twelfth capacitive element comprising a first terminal and a second terminal, wherein the first terminal of the twelfth capacitive element is coupled to the second terminal of the seventh capacitive element and the second terminal of the twelfth capacitive element is coupled to the reference voltage terminal. [17] High-frequency filter according to claim 16, wherein: the first to twelfth capacitive elements are arranged on a first substrate; and the first to fourth inductive elements are arranged on a second substrate. [18] High-frequency filter according to claim 17, wherein: the second substrate comprises a first material layer and a second material layer, the second inductive element, the third inductive element and the fourth inductive element are arranged at least in the first layer of material, and the first inductive element is located at least in the second layer of material. [19] High-frequency filter according to claim 18, further comprising: a parasitic inductance comprising a first terminal and a second terminal, wherein the first terminal of the parasitic inductance is coupled to the first node and the second terminal of the parasitic inductance is coupled to the reference voltage terminal; wherein the parasitic inductance is located at least in the first layer of material; and When viewed in a direction perpendicular to the second substrate, the parasitic inductance is located between the second inductive element and the first inductive element. [20] High-frequency filter according to any one of claims 7 to 19, wherein: If the first transmitter-receiver terminal is a signal input terminal and the second transmitter-receiver terminal is a signal output terminal, a current flows through the first inductive element, the second inductive element, the third inductive element, and the fourth inductive element in a counterclockwise direction; If the first transmitter-receiver terminal is a signal output terminal and the second transmitter-receiver terminal is a signal input terminal, a current flows through the first inductive element, the third inductive element and the fourth inductive element along a counterclockwise direction and a current flows through the second inductive element along a clockwise direction.

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