Vertically cross-coupled high-rectangular-coefficient broadband suppression high-speed differential filter chip

Abstract

The invention discloses a vertical cross coupling high-rectangular coefficient broadband suppression high-speed differential filter chip, belongs to the technical field of microwave passive devices, and solves the problem of how to design a high-speed differential filter chip with compact lumped element layout, high rectangular coefficient and broadband suppression. An input end transmission line, an output end transmission line, a pi-shaped resonator and an inverted L-shaped impedance matching branch knot are connected in series on a main circuit, a first cross coupling structure and a second cross coupling structure are connected in parallel on the main circuit, the main circuit is bent into a U shape to be vertically arranged, the length of the transmission line connecting capacitors Cd1 and Cd2 is effectively reduced, and lumped elements in topology are arranged more compactly; the capacitors Cd1 and Cd2 do not increase the order of the filter and add additional circuits, compared with a topology of transverse layout of a main path, the differential filter chip has the advantages that a lot of transverse dimensions are saved, the total area of the circuit is reduced, the integration level of the differential filter chip is improved, and the trend of miniaturization and high integration level of a current radio frequency system circuit is met.

Description

Technical Field

[0001] The present invention belongs to the technical field of microwave passive devices, and relates to a vertically cross-coupled high rectangularity coefficient broadband rejection high-speed differential filter chip. Background Art

[0002] The rapidly developing wireless communication technology today has greatly increased the demand for transmitting high-quality signals with high data rates. Due to its unique structure, the differential circuit has better anti-interference and anti-noise capabilities compared with the traditional single-ended circuit, so it is widely used to obtain a higher transmission data rate. However, on the other hand, it also brings serious common-mode (CM) interference noise radiation problems. The differential filter has the advantages of anti-noise, low electromagnetic interference, convenient connection with other differential circuits, and can filter CM noise. At the same time, the highly selective filter has always been the focus of attention in the field of high-speed circuits because of its high rectangularity coefficient, high out-of-band rejection, and good in-band matching. Moreover, due to the continuous increase in the working frequency spectrum range of high-speed communication, the transmission performance will be affected by spurious responses and accompanied by interference from nearby frequencies. Therefore, severe requirements are put forward for the performance of the designed differential filter. Therefore, it is necessary to design a high-speed differential filter with a high rectangularity coefficient and broadband rejection performance and capable of combating common-mode noise to filter out the influence of out-of-band noise and in-band common-mode signals.

[0003] Most of the studies on traditional high-speed differential filters are based on board-based designs, such as defective ground structures (DGS), transmission line resonators, and mushroom-shaped multimode resonators. However, the use of printed circuit boards (PCB) or low-temperature co-fired ceramics (LTCC) technology limits the miniaturized design of microwave circuit systems. In addition, the three-dimensional integrated IPD technology can provide circuit designs with low cost and ultra-compact physical sizes. The existing studies on differential filters based on IPD technology have broadband CM rejection and ultra-small physical sizes. However, due to the small number of zeros, the out-of-band rejection depth is limited. Moreover, the traditional topology filters designed using lumped elements with IPD technology can improve the out-of-band rejection and rectangularity coefficient by increasing the order, but at the same time, it will also increase the in-band insertion loss, and increasing the order will also greatly increase the size of the filter, and the non-compact topology layout will also waste a lot of circuit area, which is not conducive to the design of miniaturized and integrated microwave circuit systems.

[0004] Therefore, in the design of high-speed differential filters, how to reduce the circuit size while ensuring excellent performance of out-of-band rejection, rectangularity coefficient, and in-band insertion loss, and how to reasonably design a compact topology layout and improve the integration degree are urgent problems to be solved currently. Summary of the Invention

[0005] The technical solution of the present invention is used to solve the problem of how to design a high-speed differential filter chip with a compact layout of lumped elements, a high rectangularity coefficient, and broadband suppression.

[0006] The present invention solves the above technical problems through the following technical solutions:

[0007] A vertical cross-coupled high-rectangularity coefficient broadband suppression high-speed differential filter chip, comprising: a microwave dielectric substrate (10), on which two symmetric filter circuits and two grounding capacitors C are attached x ; Each filter circuit includes: one π-shaped resonator, two Г-shaped impedance matching stubs, a first cross-coupling structure, a second cross-coupling structure, an input transmission line (11), and an output transmission line (12); The π-shaped resonator includes: one circular inductor L1, two circular inductors L2, two circular inductors L3, and two capacitors C2; The two Г-shaped impedance matching stubs respectively include: one circular inductor L4, one circular inductor L5, one capacitor C4, and one capacitor C5; The first cross-coupling structure includes: one capacitor C d1 ; The second cross-coupling structure includes: one capacitor C d2 ; One end of the two capacitors C5 is respectively connected to the corresponding grounding vias, the other ends of the two capacitors C5 are respectively connected to one end of the two circular inductors L5 correspondingly, the other ends of the two circular inductors L5 are respectively connected to one end of the two circular inductors L4 correspondingly, the other ends of the two circular inductors L4 are respectively connected to one end of the two capacitors C4 correspondingly, the other ends of the two capacitors C4 are respectively connected to one end of the two circular inductors L3 correspondingly, the other ends of the two circular inductors L3 are respectively connected to one end of the two circular inductors L1 correspondingly, the other ends of the two circular inductors L1 are respectively connected to one end of the two grounding capacitors C x correspondingly, and the other ends of the two grounding capacitors C x are connected to the corresponding grounding vias; The two ends of the capacitor C d2 are respectively connected to the connection microstrip line between the two circular inductors L4 and L5. One end of the input transmission line (11) is connected to one end of the capacitor C d2 , the other end of the input transmission line (11) is used as the signal input port of the filter circuit and is connected to the pad, one end of the output transmission line (12) is connected to the other end of the capacitor C d2 , and the other end of the output transmission line (12) is used as the signal output port of the filter circuit and is connected to the pad; The capacitor C d1Both ends are respectively connected to the connection microstrip lines of two circular inductors L3 and L4; both ends of the circular inductor L1 are respectively connected to the connection microstrip lines of two circular inductors L2 and L3, and one ends of two capacitors C2 are respectively connected to the corresponding ends of the circular inductor L1, and the other ends of two capacitors C2 are respectively connected to the corresponding ground vias.

[0008] Further, three circular inductors L1 and L2 are connected in series on the main path of the π-shaped resonator, and then two grounded parallel resonances formed by cascading the circular inductor L3 and the capacitor C2 are used to generate two poles to provide a passband for the subsequent parallel capacitor C d1 The resonator formed provides a passband, and the calculation formula for the generated poles is:

[0009]

[0010]

[0011] where f1 and f2 are the frequency points of the two poles generated by the π-shaped resonator respectively, and ω2 is the angular frequency.

[0012] Further, the capacitor C in the first cross-coupling structure d1 is connected to both ends of the π-shaped resonator to generate one zero point at each of the high-frequency and low-frequency bands outside the passband respectively. The calculation formulas for the two zero points generated by the first cross-coupling structure are:

[0013]

[0014] where f TZ3 and f TZ4 are the frequency points of the two generated zero points, and ω3 and ω4 are the angular frequencies.

[0015] Further, the Г-type impedance matching stub is connected in series at both ends of the π-shaped resonator to generate one pole in the passband to improve the flatness in the passband, and at the same time generate an additional zero point at the high-frequency band outside the passband to improve the out-of-band rejection width of the filter. The calculation formulas for the generated zero point and pole are:

[0016]

[0017] where f TZ5 is the frequency point of the zero point generated by the series resonance matching structure, and f3 is the frequency point of the pole generated by the series resonance matching structure.

[0018] Further, the second cross-coupling structure is connected between the signal input port and the signal output port of the filter circuit to generate one zero point at each of the high-frequency and low-frequency bands outside the passband respectively.

[0019] Further, two grounded capacitors Cx Two additional zeros are generated in the common - mode mode, and the calculation formula is:

[0020]

[0021] where f TZ0 、f TZ1 are the frequency points of the two additional zeros generated in the common - mode mode respectively.

[0022] Preferably, the material of the microwave dielectric substrate (10) is GaAs, the dielectric constant is 12.9, the loss tangent value is 0.001, and the thickness is 0.1 mm.

[0023] The advantages of the present invention are as follows:

[0024] The differential filter chip of the present invention uses two high - performance filter circuits arranged symmetrically up and down. After being excited by differential - mode and common - mode signals, the symmetry plane is equivalent to a magnetic wall and an electric wall respectively. Only the magnetic wall can excite two parallel - grounded capacitors on the symmetry plane, forming two zeros in the passband to suppress the in - band common - mode signal; each band - pass filter is composed of a π - type topology circuit in parallel with a capacitor, Γ - type impedance - matching stubs with filtering effects at both left and right ends, and a capacitor connecting the input and output ports. The π - type topology circuit has a band - pass effect and is beneficial to compact layout; the two capacitors introduce two - stage cross - coupling, introducing four additional zeros without increasing the filter order to improve the rectangularity coefficient and increase the out - of - band rejection ratio; the Γ - type impedance - matching stubs can improve the in - band flatness, and can also increase the rectangularity coefficient and the out - of - band rejection ratio; in order to reduce the size of the filter, a vertical network topology is adopted to reduce the lateral area. Compared with the traditional topology, this topology greatly reduces the transmission - line length and the lateral area of the filter, achieving topological compactness while ensuring a high rectangularity coefficient and wide - band suppression. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is the three - dimensional front view of the vertical cross - coupling high - rectangularity - coefficient wide - band - suppression high - speed differential filter chip of the present invention;

[0026] Figure 2 is the three - dimensional front view of the upper half of the vertical cross - coupling high - rectangularity - coefficient wide - band - suppression high - speed differential filter chip of the present invention;

[0027] Figure 3 is the differential - mode equivalent half - circuit schematic diagram of the vertical cross - coupling high - rectangularity - coefficient wide - band - suppression high - speed differential filter chip of the present invention;

[0028] Figure 4 is the design principle block diagram of the vertical cross - coupling high - rectangularity - coefficient wide - band - suppression high - speed differential filter chip of the present invention;

[0029] Figure 5 Schematic differential S-parameter comparison between the π-type topology and the π-type topology with cross-coupling of the present invention;

[0030] Figure 6 S in the differential S-parameters of the π-type topology with cross-coupling, the differential filter without cross-coupling, and the differential filter with cross-coupling of the present invention dd21 Comparison;

[0031] Figure 7 S in the differential S-parameters at different values of C in the vertical cross-coupled high rectangularity coefficient broadband rejection high-speed differential filter chip of the present invention d1 Comparison; dd21 Comparison;

[0032] Figure 8 S in the differential S-parameters at different values of C in the vertical cross-coupled high rectangularity coefficient broadband rejection high-speed differential filter chip of the present invention d2 Comparison; dd21 Comparison;

[0033] Figure 9 In the full-wave simulation differential S-parameters of the vertical cross-coupled high rectangularity coefficient broadband rejection high-speed differential filter chip of the present invention;

[0034] Figure 10 Common-mode half-circuit full-wave simulation differential S-parameters of the vertical cross-coupled high rectangularity coefficient broadband rejection high-speed differential filter chip of the present invention

[0035] Figure 11 Full-wave simulation differential S-parameters of the vertical cross-coupled high rectangularity coefficient broadband rejection high-speed differential filter chip of the present invention. Detailed implementation manners

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings of the specification and specific embodiments:

[0038] 1. Composition structure

[0039] As Figure 1As shown in the figure, it is the three-dimensional front view of a vertical cross-coupled high rectangular coefficient broadband suppression high-speed differential filter chip according to an embodiment of the present invention. It can be seen that a vertical cross-coupled high rectangular coefficient broadband suppression high-speed differential filter chip according to an embodiment of the present invention is a centrosymmetric structure; specifically, a vertical cross-coupled high rectangular coefficient broadband suppression high-speed differential filter chip according to an embodiment of the present invention includes: a microwave dielectric substrate 10, and two identical left-right symmetric filter circuits and two grounding capacitors C are pasted on the microwave dielectric substrate 10 x .

[0040] Preferably, the material of the microwave dielectric substrate 10 is GaAs, the dielectric constant is 12.9, the loss tangent value is 0.001, and the thickness is 0.1 mm.

[0041] As Figure 2 and Figure 3 shown, each filter circuit includes: one π-shaped resonator, two Г-shaped impedance matching stubs, a first cross-coupling structure, a second cross-coupling structure, an input transmission line 11, and an output transmission line 12. The π-shaped resonator includes: one circular inductor L1, two circular inductors L2, two circular inductors L3, and two capacitors C2; the two Г-shaped impedance matching stubs respectively include: one circular inductor L4, one circular inductor L5, one capacitor C4, and one capacitor C5; the first cross-coupling structure includes: one capacitor C d1 ; the second cross-coupling structure includes: one capacitor C d2 .

[0042] One ends of the two capacitors C5 are respectively connected to the corresponding grounding vias through microstrip lines, the other ends of the two capacitors C5 are respectively connected to one ends of the two circular inductors L5 through microstrip lines, the other ends of the two circular inductors L5 are respectively connected to one ends of the two circular inductors L4 through microstrip lines, the other ends of the two circular inductors L4 are respectively connected to one ends of the two capacitors C4 through microstrip lines, the other ends of the two capacitors C4 are respectively connected to one ends of the two circular inductors L3 through microstrip lines, the other ends of the two circular inductors L3 are respectively connected to one ends of the two circular inductors L1 through microstrip lines, the other ends of the two circular inductors L1 are respectively connected to one ends of the two grounding capacitors C x correspondingly, and the other ends of the two grounding capacitors C x are connected to the corresponding grounding vias through microstrip lines. Both ends of the capacitor C d2 are respectively connected to the connection microstrip line between the two circular inductors L4 and L5. One end of the input transmission line 11 is connected to one end of the capacitor C d2 through a microstrip line, the other end of the input transmission line 11 is used as the signal input port of the filter circuit and is connected to the pad through a microstrip line, and one end of the output transmission line 12 is connected to the capacitor Cd2 The other end is connected through a microstrip line, and the other end of the output transmission line 12 is used as the signal output port of the filter circuit and is connected to the pad through a microstrip line. Capacitor C d1 Both ends of it are respectively connected to the connecting microstrip line between two circular inductors L3 and L4. Both ends of the circular inductor L1 are respectively connected to the connecting microstrip line between two circular inductors L2 and L3. One ends of two capacitors C2 are respectively connected to both ends of the circular inductor L1 through microstrip lines in a corresponding manner, and the other ends of the two capacitors C2 are respectively connected to the corresponding grounding vias through microstrip lines.

[0043] 2. Working principle

[0044] A vertical cross-coupled high rectangular coefficient broadband suppression high-speed differential filter chip according to an embodiment of the present invention is a centrosymmetric structure. When the high-speed differential filter is respectively excited by differential-mode and common-mode signals, the xoz symmetry plane is equivalent to a magnetic wall and an electric wall respectively. Only the magnetic wall can excite two shunt grounding capacitors C on the xoz symmetry plane x ; when a differential-mode signal with a phase difference of 180° is input to the differential filter, the xoz symmetry plane is equivalent to a short circuit, and the two grounding capacitors C x are short-circuited, and the filter circuit exhibits the band-pass filtering characteristics of high rectangular coefficient and broadband suppression; when a common-mode signal with a phase difference of 0° is input to the differential filter, the xoz symmetry plane is equivalent to an open circuit, and the two grounding capacitors C x are incorporated into two filter circuits, forming two series resonances, generating two zeros in the passband to suppress in-band signals, and the filter circuit exhibits a band-stop characteristic to perform broadband suppression on the input signal. Therefore, broadband suppression of common-mode noise and band-pass filtering with high rectangular coefficient and broadband suppression of differential-mode signals are simultaneously achieved.

[0045] As Figures 2 to 4 shown, three circular inductors L1 and L2 are connected in series on the main path of the π-type resonator, and then two grounded parallel resonances (two grounded parallel resonances formed by the circular inductor L3 and the capacitor C2) are cascaded to generate two poles, providing a passband for the resonator formed by the subsequent shunt capacitor C d1 . The calculation formula for the generated poles is as follows:

[0046]

[0047] where f1 and f2 are the frequency points of the two poles generated by the π-type resonator respectively, and ω2 is the angular frequency.

[0048] The capacitor C in the first cross-coupling structure d1Connected to both ends of the π-shaped resonator, it is used to generate one zero point at high frequency and low frequency outside the passband respectively, achieving the improvement of the rectangular coefficient and out-of-band suppression of the filter without increasing the filter order. Compared with the traditional method of increasing the filter order, adding coupling capacitors can effectively avoid the increase in insertion loss and circuit size caused by increasing the filter order, which is beneficial to reducing the circuit area and ensuring the miniaturization of the circuit.

[0049] The calculation formulas for the two zero points generated by the first cross-coupling structure are:

[0050]

[0051] Among them, f TZ3 、f TZ4 are the frequency points of the two generated zero points, and ω3 and ω4 are angular frequencies.

[0052] The Г-type impedance matching stub is connected in series at both ends of the π-shaped resonator, which can generate a pole in the passband to improve the flatness in the passband, and at the same time generate an additional zero point at high frequency outside the passband to further improve the out-of-band suppression width of the filter. The topology of the Г-type impedance matching stub is suitable for layout in the vertical direction, which is beneficial to the compact layout of components in the circuit, reduces the circuit size, and improves the circuit integration.

[0053] The calculation formulas for the generated zero points and poles are:

[0054]

[0055]

[0056] Among them, f TZ5 is the frequency point of the zero point generated by the series resonance matching structure, and f3 is the frequency point of the pole generated by the series resonance matching structure.

[0057] The second cross-coupling structure is connected between the signal input port and the signal output port of the filter circuit, and is used to generate one zero point at high frequency and low frequency outside the passband respectively, improving the rectangular coefficient and out-of-band suppression of the filter without increasing the filter order.

[0058] Two grounded capacitors C x generate two additional zero points in the common-mode mode, and the calculation formula is:

[0059]

[0060] Among them, f TZ0 、f TZ1 are the frequency points of the two additional zero points generated in the common-mode mode respectively.

[0061] 3. Performance Analysis

[0062] As Figure 1 and Figure 2 shown, the main path of the filtering circuit of the high-speed differential filter of the present invention adopts a vertical network topology layout. The input transmission line, output transmission line, π-shaped resonator, and Г-shaped impedance matching stub are connected in series on the main path. Moreover, the first and second cross-coupling structures are connected in parallel on the main path. Bending the main path into a U shape for vertical layout can effectively reduce the connection lengths of the two coupling capacitors C d1 and C d2 to the main path. Reducing the lengths of the transmission lines will reduce the generation of additional high-frequency parasitic parameters, making the arrangement of the lumped elements in the topology more compact; and the two added capacitors C d1 and C d2 do not increase the order of the filter and add additional circuits, which is beneficial to improving the miniaturization of the circuit and the integration of RF passive devices; compared with the topology with a horizontal layout of the main path, it saves a lot of horizontal dimensions and also reduces the overall area of the circuit, improving the integration of the proposed differential filter chip, which is in line with the current trend of miniaturization and high integration of RF system circuits.

[0063] As Figure 5 shown, the π-shaped resonator with the added parallel coupling capacitor C d1 can form one zero at both high frequency and low frequency without adding additional circuits and filter order, greatly improving the rectangularity coefficient of the band-pass filter.

[0064] As Figure 6 shown, after adding the Г-shaped impedance matching stub, the filter not only has a flatter in-band response and an improved rectangularity coefficient, but also forms one zero at high frequency, greatly improving the out-of-band rejection.

[0065] As Figure 7 shown, the capacitor C d1 controls the second and fifth zeros. As the value of C d1 increases, the two zeros move towards high frequency, and the out-of-band rejection width becomes wider while the out-of-band rejection becomes weaker.

[0066] As Figure 8 shown, after adding the capacitor C d2 , the filter forms one zero at both high frequency and low frequency without increasing the order and additional circuits, improving the out-of-band rejection width of the band-pass filter. The capacitor C d2 controls the first and fifth zeros. As the value of C d2 increases, the two zeros move towards high frequency, and the out-of-band rejection width becomes wider while the out-of-band rejection becomes weaker.

[0067] As Figure 9As shown, when processing differential-mode signals, the differential filter proposed by the present invention can form two zeros at low frequencies, three zeros at high frequencies, and four poles in the passband. This differential filter has good out-of-band rejection depth and width, as well as good rectangularity coefficient and in-band flatness.

[0068] As Figure 10 shown, when processing common-mode signals, the differential filter proposed by the present invention can form two zeros in the passband, and cooperate with three zeros outside the passband to achieve wideband suppression of common-mode signals.

[0069] As Figure 11 shown, it can be seen from the figure that the differential filter of the present invention not only has good selectivity for differential-mode signals, but also has good rectangularity coefficient and out-of-band rejection width with small insertion loss in the passband. It suppresses common-mode signals in the passband and also has wideband suppression for common-mode signals outside the passband.

[0070] 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 for some of the technical features. However, such modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vertical cross-coupled high rectangularity coefficient broadband rejection high-speed differential filter chip, characterized in that, Including: Microwave dielectric substrate (10), with two symmetric filter circuits and two grounding capacitors C attached to the microwave dielectric substrate (10). x ; Each filter circuit includes: one π-shaped resonator, two Г-shaped impedance matching stubs, a first cross-coupling structure, a second cross-coupling structure, an input transmission line (11), and an output transmission line (12); The π-shaped resonator includes: one circular inductor L1, two circular inductors L2, two circular inductors L3, and two capacitors C2; The two Г-shaped impedance matching stubs respectively include: one circular inductor L4, one circular inductor L5, one capacitor C4, and one capacitor C5; The first cross-coupling structure includes: one capacitor C d1 ; The second cross-coupling structure includes: one capacitor C d2 ; One end of each of the two capacitors C5 is respectively connected to the corresponding grounding via hole, the other ends of the two capacitors C5 are respectively connected to one end of the two circular inductors L5 correspondingly, the other ends of the two circular inductors L5 are respectively connected to one end of the two circular inductors L4 correspondingly, the other ends of the two circular inductors L4 are respectively connected to one end of the two capacitors C4 correspondingly, the other ends of the two capacitors C4 are respectively connected to one end of the two circular inductors L3 correspondingly, the other ends of the two circular inductors L3 are respectively connected to one end of the two circular inductors L1 correspondingly, the other ends of the two circular inductors L1 are respectively connected to one end of the two grounding capacitors C x correspondingly, and the other ends of the two grounding capacitors C x are connected to the corresponding grounding via holes; The two ends of the capacitor C d2 are respectively connected to the connection microstrip line between the two circular inductors L4 and L5. One end of the input transmission line (11) is connected to one end of the capacitor C d2 , and the other end of the input transmission line (11) serves as the signal input port of the filter circuit and is connected to the pad. One end of the output transmission line (12) is connected to the other end of the capacitor C d2 , and the other end of the output transmission line (12) serves as the signal output port of the filter circuit and is connected to the pad; The two ends of the capacitor C d1 are respectively connected to the connection microstrip line between the two circular inductors L3 and L4; The two ends of the circular inductor L1 are respectively connected to the connection microstrip line between the two circular inductors L2 and L3. One end of each of the two capacitors C2 is respectively connected to the two ends of the circular inductor L1 correspondingly, and the other ends of the two capacitors C2 are respectively connected to the corresponding grounding via holes.

2. The vertical cross-coupled high rectangularity coefficient wideband rejection high-speed differential filter chip according to claim 1, wherein Three circular inductors L1 and L2 are connected in series on the main path of the π-shaped resonator, and then two grounded parallel resonances formed by cascading the circular inductor L3 and the capacitor C2 are used to generate two poles, providing a passband for the subsequent parallel capacitor C d1 The resonator formed provides a passband, and the calculation formula for the generated poles is as follows: Among them, f1 and f2 are the frequency points of the two poles generated by the π-shaped resonator respectively, and ω2 is the angular frequency.

3. The vertical cross-coupled high rectangularity coefficient wideband rejection high-speed differential filter chip according to claim 1, wherein Capacitor C in the first cross-coupling structure d1 Connected to both ends of the π-shaped resonator to generate a zero point at each of the high frequency and low frequency outside the passband respectively. The calculation formulas for the two zero points generated by the first cross-coupling structure are as follows: where f TZ3 and f TZ4 are the frequency points of the two generated zeros, and ω3 and ω4 are angular frequencies.

4. The vertically cross-coupled wideband suppression high rectangularity coefficient high-speed differential filter chip according to claim 1, wherein The Г-shaped impedance matching stub is connected in series at both ends of the π-shaped resonator to generate a pole in the passband to improve the flatness in the passband. At the same time, an additional zero is generated at the high frequency outside the passband to improve the out-of-band rejection width of the filter. The calculation formulas for the generated zero and pole are: Among them, f TZ5 is the frequency point of the zero point generated by the series resonance matching structure, and f3 is the frequency point of the pole generated by the series resonance matching structure.

5. The vertical cross-coupled high rectangularity coefficient broadband rejection high-speed differential filter chip according to claim 1, characterized in that, The second cross-coupling structure is connected between the signal input port and the signal output port of the filter circuit to generate one zero at each of the high frequency and low frequency outside the passband respectively.

6. The vertical cross-coupled high rectangularity coefficient wideband rejection high-speed differential filter chip according to claim 1, wherein Two grounding capacitors C x Generate two additional zeros in the common - mode mode, and the calculation formula is: where f TZ0 and f TZ1 are the frequency points of two additional zeros generated in the common mode, respectively.

7. The vertical cross-coupled high rectangularity coefficient wideband rejection high-speed differential filter chip according to claim 1, wherein The material of the microwave dielectric substrate (10) is GaAs, the dielectric constant is 12.9, the loss tangent value is 0.001, and the thickness is 0.1 mm.

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