CN219459030U - Topology structure, filter and communication equipment - Google Patents

Abstract

The embodiment of the utility model provides a topological structure, a filter and communication equipment, wherein the topological structure is suitable for the filter and comprises the following components: the serial branch comprises 4 serial stages, and the connection nodes of each serial stage are sequentially connected end to end; the parallel branch circuit comprises 5 parallel stages, the first end of each parallel stage is respectively connected with the connecting node of each serial stage, the second end is connected with the grounding inductance of the parallel branch circuit, and the second ends of at least two parallel stages are connected with the same grounding inductance. According to the topological structure, the filter and the communication equipment provided by the embodiment of the utility model, the out-of-band rejection and the insertion loss of the filter are balanced while the out-of-band rejection effect of the filter is improved through the arrangement of the number of the series-connected stages and the parallel-connected stages, and the out-of-band rejection and the insertion loss of the filter are balanced.

Description

Topology structure, filter and communication equipment

Technical Field

The embodiment of the application relates to the technical field of images, in particular to a topological structure, a filter and communication equipment.

Background

Filters are devices for eliminating interference in communication systems, and play an important role in communication systems, so that the improvement of the performance of the filters is of great importance to the improvement of the performance of the communication systems, and the topology is a main aspect affecting the performance of the filters. Therefore, how to provide a topology technical solution to improve the performance of the filter becomes a technical problem to be solved.

Disclosure of Invention

In view of this, embodiments of the present application provide a topology, a filter, and a communication device to improve the performance of the filter.

To solve the above problem, an embodiment of the present application provides a topology structure, which is applicable to a filter, including:

the series branch comprises 4 series stages, and the connecting nodes of the series stages are sequentially connected end to end;

the parallel branch circuit comprises 5 parallel stages, wherein the first end of each parallel stage is respectively connected with the connection node of each serial stage, the second end of each parallel stage is connected with the grounding inductance of the parallel branch circuit, and the second ends of at least two parallel stages are connected with the same grounding inductance.

Optionally, the number of the inductors to ground is 2, the second ends of two parallel stages are connected to the same inductor to ground, and the second ends of three parallel stages are connected to the other inductor to ground.

Optionally, the series branch further comprises at least one of an input series inductance connected between the input port of the topology and the first connection node of the connection node and an output series inductance connected between the output port of the topology and the fifth connection node of the connection node.

Optionally, the number of the input series inductors is at least two, and each input series inductor is connected end to end in sequence.

Optionally, the number of the output series inductors is at least two, and each output series inductor is connected end to end in sequence.

Optionally, the input series inductance has an inductance value in the range of 0.5nH-5nH.

Optionally, the output series inductor has an inductance value in the range of 0.5nH-5nH.

Optionally, the method further comprises:

and the metal connection structure is connected between the second end of the parallel stage and the ground inductance.

Optionally, the parallel stage and the series stage each comprise a resonator comprising:

an upper electrode with a thickness ranging from 250nm to 400nm;

a piezoelectric layer having a thickness in the range of 0.6 μm to 1 μm;

the lower electrode has a thickness in the range of 250nm to 400nm.

Optionally, the resonator includes a first resonator and a second resonator connected in series, and the series connection manner of the resonators includes:

the upper electrode of the first resonator is connected with the upper electrode of the second resonator;

the lower electrode of the first resonator is connected with the lower electrode of the second resonator;

the lower electrode of the first resonator is connected with the upper electrode of the second resonator through a conductive structure penetrating through the piezoelectric layer; and/or

The upper electrode of the first resonator is connected to the lower electrode of the second resonator through a conductive structure penetrating the piezoelectric layer.

Optionally, the resonator includes a first resonator and a second resonator connected in parallel, and the parallel connection manner of the resonators includes:

the upper electrode of the first resonator is connected with the upper electrode of the second resonator, and the lower electrode of the first resonator is connected with the lower electrode of the second resonator; and/or

The upper electrode of the first resonator is connected with the lower electrode of the second resonator through a conductive structure penetrating the piezoelectric layer, and the lower electrode of the first resonator is connected with the upper electrode of the second resonator through a conductive structure penetrating the piezoelectric layer.

To solve the foregoing problems, the present application further provides a filter comprising a topology as set forth in any one of the preceding claims.

Optionally, the filter has a passband center frequency in the range of 2.3GHz-2.7GHz.

Optionally, the insertion loss worst value in the pass band of the filter is-2.5 dB.

Optionally, the filter has a worst passband insertion loss ripple of-1.8 dB.

Optionally, the suppression value of the filter is less than-40 dB in the range from 250MHz reduction of the center frequency of the passband to 150MHz reduction of the center frequency of the passband;

the suppression value of the filter is smaller than-50 dB in the range from 150MHz reduction of the center frequency of the passband to 90MHz reduction of the center frequency of the passband;

the suppression value of the filter is smaller than-45 dB in the range from 90MHz reduction of the center frequency of the passband to 75MHz reduction of the center frequency of the passband;

the suppression value of the filter is smaller than-50 dB in the range from 65MHz to 110MHz of the center frequency of the passband;

the suppression value of the filter is smaller than-45 dB in the range from 110MHz to 130 MHz;

the suppression value of the filter is less than-40 dB in the range from 130MHz increase in the center frequency of the passband to 250MHz increase in the center frequency of the passband.

The present application also provides a communication device comprising a filter as claimed in any one of the preceding claims to solve the aforementioned problems.

Compared with the prior art, the technical scheme of the embodiment of the application has the following advantages:

the topological structure provided by the embodiment of the application comprises a series branch circuit, wherein the series branch circuit comprises 4 series stages, and the connection nodes of the series stages are sequentially connected end to end; the parallel branch circuit comprises 5 parallel stages, wherein the first end of each parallel stage is respectively connected with the connection node of each serial stage, the second end of each parallel stage is connected with the grounding inductance of the parallel branch circuit, and the second ends of at least two parallel stages are connected with the same grounding inductance.

It can be seen that, in the topology structure provided by the embodiment of the application, the number of serial stages is set to 4, and the number of parallel stages is set to 5, so that the number of parallel stages is more than that of serial stages, thereby increasing the number of parallel stages, improving the out-of-band rejection of a filter using the topology structure, improving the out-of-band rejection effect of the filter, and setting the number of serial stages and the number of parallel stages, and also considering the out-of-band rejection and the insertion loss of the filter, so that the out-of-band rejection and the insertion loss are more balanced, one of them is avoided to be very good, and the other is very bad; furthermore, in the topology structure provided by the embodiment of the utility model, the second ends of at least two parallel stages are connected to the same grounding inductor, so that the connection quantity of the grounding inductors in the topology structure can be reduced, and the inductance value of the grounding inductor and the use quantity of the grounding inductors are in direct proportion, so that the inductance value generated by the grounding inductor can be reduced, and the inductance value of the grounding inductor and the loss value of the inductor are in direct proportion, therefore, the loss of the grounding inductor can be reduced, the quality factor of the filter is improved, and the passband insertion loss of the filter is improved.

Therefore, the technical scheme provided by the embodiment of the application realizes the out-of-band rejection and insertion loss of the filter while improving the out-of-band rejection effect of the filter through the arrangement of the serial stages and the parallel stages, so that the out-of-band rejection and insertion loss are more balanced, and on the other hand, the connection quantity of the grounding sense can be reduced through the connection of the second ends of at least two parallel stages to the same grounding sense, and the total inductance value generated by the grounding sense is further reduced, so that the loss of the grounding sense can be reduced, the quality factor of the filter is improved, and the passband insertion loss of the filter is improved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present application, and that other drawings may be obtained according to the provided drawings without inventive effort to a person skilled in the art.

FIG. 1 is a schematic diagram of a topology of a filter

Fig. 2 is a first structural schematic diagram of a topology of a filter according to an embodiment of the present utility model;

FIG. 3 is a second schematic diagram of a topology of a filter according to an embodiment of the present utility model;

fig. 4 is a third structural schematic diagram of a topology of a filter according to an embodiment of the present utility model;

FIG. 5 is a fourth schematic diagram of a topology of a filter according to an embodiment of the present utility model;

FIG. 6 is a fifth schematic diagram of a topology of a filter according to an embodiment of the present utility model;

FIG. 7 is a sixth schematic diagram of a topology of a filter according to an embodiment of the present utility model;

fig. 8 is a seventh structural schematic diagram of a topology of a filter according to an embodiment of the present utility model;

fig. 9 is an eighth structural schematic diagram of a topology of a filter according to an embodiment of the present utility model;

FIG. 10 is a schematic diagram of a resonator of a filter according to an embodiment of the present utility model;

fig. 11 is a schematic diagram of a first structure in which resonators of a filter according to an embodiment of the present utility model are connected in series;

fig. 12 is a second schematic diagram of a series connection of resonators of a filter according to an embodiment of the present utility model;

fig. 13 is a schematic diagram of a third structure in which resonators of a filter according to an embodiment of the present utility model are connected in series;

Fig. 14 is a fourth schematic diagram of a series connection of resonators of a filter according to an embodiment of the present utility model;

fig. 15 is a schematic view of a fifth structure in which resonators of a filter according to an embodiment of the present utility model are connected in series;

fig. 16 is a sixth structural schematic diagram of a series connection of resonators of a filter provided by an embodiment of the present utility model;

fig. 17 is a first schematic structural view of a parallel connection of resonators of a filter according to an embodiment of the present utility model;

fig. 18 is a second schematic structural view of a parallel connection of resonators of a filter according to an embodiment of the present utility model;

fig. 19 is a transmission graph of a filter provided by an embodiment of the present utility model.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

The filter is a filter circuit composed of resonators, connection structures of the resonators and necessary matching elements, and the matching elements comprise passive devices such as inductors, capacitors and the like. The filter can effectively filter the frequency points of the specific frequency or the frequencies outside the frequency points in the power line to obtain a power signal of the specific frequency or eliminate the power signal of the specific frequency. Thus, the filter is one of the essential key components in the communication system and can be used to make frequency selection, i.e. pass the desired power signal frequency while reflecting the undesired interference signal frequency.

To facilitate understanding of the overall structure and functional implementation of the filter, in one example, embodiments of the present utility model are described in connection with the topology of the basic filter; referring to fig. 1, fig. 1 is a schematic diagram of a topology of a filter.

As shown in fig. 1, the topology structure of the filter includes an input port 01, an output port 02 and a ground port 03; a serial branch 04 connected to the input port 01 and the output port 02, and a parallel branch 05 connected to the serial branch 04; the serial branch 04 comprises a plurality of serial stages (Se) 041, and the parallel branch 05 comprises a plurality of parallel stages (Sh) 051; and a ground inductance 052 connected between the second end of each parallel stage 051 and the ground port 03; each of the series stage 041 or the parallel stage 051 may be formed by connecting a plurality of resonators in series, may be formed by connecting a plurality of resonators in parallel, or may be formed by connecting a plurality of resonators in series and connecting a plurality of resonators in parallel.

When the filter works, an electric signal is input to the serial branch 04 and the parallel branch 05 of the filter through the input port 01, so that resonators in the serial stage 041 and the parallel stage 051 can convert the input electric signal into an acoustic signal, and then convert the acoustic signal into an electric signal to be output. The structural arrangement of the resonator ensures that the resonator has different electrical impedance for signals with different frequencies, so that transmission and reflection of different frequencies are realized, and filter characteristics are formed.

It can be seen that the use of filters is very important in communication systems. Thus, as the performance of the communication system increases, the requirements for the performance improvement of the filter become higher and higher. The performance of a filter can be generally described by performance metrics such as order (number of stages), absolute or relative bandwidth, out-of-band rejection, passband insertion loss, return loss (passband echo), etc. The out-of-band rejection refers to attenuation outside the passband frequency range of the filter, and specifies how many decibels (dB) of frequencies (Hz) outside the passband of the filter are reduced, so that the selectivity of the filter to unwanted frequency signals can be represented, and the size of the out-of-band rejection has a great influence on the performance of the filter; while passband insertion loss refers to the loss of power caused by the filter in decibels (dB), it is readily understood that the smaller the passband insertion loss, the better, i.e., the closer to 0.

In designing a filter, to ensure out-of-band rejection of the filter, the out-of-band rejection of the filter is typically improved by adding more electrical devices, increasing the device area of the filter, or adding more complex packaging or design structures.

However, the design method of the filter cannot obtain better performance, or under the condition of obtaining the same out-of-band rejection, indexes such as passband insertion loss and the like are required to be sacrificed; it is therefore an urgent need to provide a suitable filter design structure to improve the performance of the filter.

In order to improve the performance of the filter, the embodiment of the utility model provides a topological structure of the filter, and the aim of effectively improving the performance of the filter is fulfilled by improving the topological structure of the filter.

Referring to fig. 2-6, fig. 2 is a schematic diagram of a first structure of a topology of a filter according to an embodiment of the utility model; FIG. 3 is a second schematic diagram of a topology of a filter according to an embodiment of the present utility model; fig. 4 is a third structural schematic diagram of a topology of a filter according to an embodiment of the present utility model; FIG. 5 is a fourth schematic diagram of a topology of a filter according to an embodiment of the present utility model; fig. 6 is a fifth structural schematic diagram of a topology of a filter according to an embodiment of the present utility model.

As shown in the figure, the topology structure of the filter provided by the embodiment of the utility model includes:

a serial branch 04 comprising 4 serial stages 041, wherein the connection nodes of the serial stages 041 are connected end to end in turn;

the parallel branch 05 comprises 5 parallel stages 051, a first end of each parallel stage 051 is respectively connected to the connection node of each serial stage 041, a second end 053 is connected to a ground inductance 052 of the parallel branch 05, and second ends 053 of at least two parallel stages 051 are connected to the same ground inductance 052.

It will be readily appreciated that the series stage (Se) 041 described herein includes series stage 1 (Se 1), series stage 2 (Se 2), series stage 3 (Se 3) and series stage 4 (Se 4) shown in the figures, and of course, each series stage (Se) 041 may be formed by a plurality of resonators in series, a plurality of resonators in parallel, or a plurality of resonators in series plus a plurality of resonators in parallel; the connection nodes of the serial stages (Se) 041 are connected end to end in sequence, which means that the serial stages (Se) 041 are connected in sequence, but the specific order of the serial stages 1, 2, 3 and 4 is not limited, and the order of the serial stages can be shown in the figure or changed; the parallel stage (Sh) 051 described herein includes a parallel stage 1 (Sh 1), a parallel stage 2 (Sh 2), a parallel stage 3 (Sh 3), a parallel stage 4 (Sh 4) and a parallel stage 5 (Sh 5) shown in the figure, and the setting sequence of each parallel stage 051 is not limited and can be adjusted as required; the second terminal 053 of the parallel stage (Sh) 051 described herein, which may also be referred to as a ground terminal, is denoted as G1, G2, G3 or G4.

It should be noted that "the second ends of the at least two parallel stages 051 are connected to the same ground inductor 052", which includes:

1), as shown in fig. 2, the second ends of two parallel stages 051 in 5 parallel stages 051 are connected to the same ground inductor 052, the other 3 parallel stages 051 are respectively connected to different ground inductors 052, of course, the second ends of the two parallel stages 051 connected to the same ground inductor 052 may be any two of the 5 parallel stages 051, may be adjacent or not adjacent, as long as the connection requirement can be achieved, the adjacent parallel stages 1 and parallel stages 2 are connected to the ground inductor 1 (LG 1) through the second end G1 (i.e. the ground end G1), the parallel stages 3 are connected to the ground inductor 2 (LG 2) through the second end G2 (i.e. the ground end G2), the parallel stages 4 are connected to the ground inductor 3 (LG 3) through the second end G3 (i.e. the ground end G4), and the parallel stages 5 are connected to the ground inductor 4 (LG 4) through the second end G4 (i.e. the ground end G4) for illustration;

2) As shown in fig. 3, the second ends of three parallel stages 051 of the 5 parallel stages 051 are connected to the same ground inductor 052, the other 2 parallel stages are respectively connected to different ground inductors 052, of course, the three parallel stages of the 5 parallel stages 051, which are connected to the same ground inductor 052, may be any three of the 5 parallel stages 051, may be adjacent or not adjacent, as long as the connection requirement can be achieved, and the adjacent parallel stages 2, 3 and 4 are connected to the ground inductor 2 (LG 2) through the second end G2 (i.e. the ground end G2) jointly, while the parallel stage 1 is connected to the ground inductor 1 (LG 1) through the second end G1 (i.e. the ground end G1), and the parallel stage 5 is connected to the ground inductor 3 (LG 3) through the second end G3 (i.e. the ground end G3) for illustration.

3) As shown in fig. 4, the second ends of four parallel stages 051 in the 5 parallel stages 051 are connected to the same ground inductor 052, the other 1 parallel stages are respectively connected to different ground inductors 052, of course, the second ends of the four parallel stages 051 connected to the same ground inductor 052 may be any four of the 5 parallel stages 051, may be adjacent or not adjacent, as long as the connection requirement can be achieved, the adjacent parallel stages 1, parallel stages 2, parallel stages 3 and parallel stages 4 are commonly connected to the ground inductor 1 (LG 1) through the second end G1 (namely, the ground end G1), and the parallel stages 5 are exemplified by the connection of the ground inductor 2 (LG 2) through the second end G2 (namely, the ground end G2).

4) As shown in fig. 5, the second ends of the 5 parallel stages 051 are all connected to the same grounding inductor 052, namely, the parallel stage 1, the parallel stage 2, the parallel stage 3, the parallel stage 4 and the parallel stage 5 are commonly connected to the grounding inductor 1 (LG 1) through the second end G1 (namely, the grounding end G1);

5) As shown in fig. 6, the second ends of two parallel stages 051 in 5 parallel stages 051 are connected to the same grounding inductor 052, the second ends of the parallel stages 051 in any two of the remaining 3 parallel stages 051 are connected to the same grounding inductor 052, the second ends of the remaining one parallel stage 051 are connected to the separate grounding inductor 052, of course, two groups of second ends 053 are connected to two parallel stages 051 of the same grounding inductor 052 and may or may not be adjacent, so long as the connection requirement can be met, the adjacent parallel stages 1 and parallel stages 2 are connected to the grounding inductor 1 (LG 1) through the second end G1 (i.e. the grounding end G1) jointly, the parallel stages 3 are connected to the grounding inductor 2 (LG 2) through the second end G2 (i.e. the grounding end G2), and the adjacent parallel stages 4 and 5 are connected to the grounding inductor (LG 3) through the second end G3 (i.e. the grounding end G3) jointly for illustration;

6) As shown in fig. 7 and 8, the number of the grounding inductors is 2, the second ends of two parallel stages 051 are connected to the same grounding inductor 052, the second ends of three parallel stages 051 are connected to the same grounding inductor 052, of course, two groups of second ends 053 are connected to two parallel stages 051 of the same grounding inductor 052 and may or may not be adjacent, so long as the connection needs can be achieved, the adjacent parallel stages 1 and parallel stages 2 in fig. 7 are connected to the grounding inductor 1 (LG 1) through the second end G1 (i.e. the grounding end G1) in common, the adjacent parallel stages 3, parallel stages 4 and parallel stages 5 are connected to the grounding inductor 2 (LG 2) through the second end G2 in common, and the adjacent parallel stages 1, parallel stages 2 and parallel stages 3 are connected to the grounding inductor 1 (i.e. the grounding end G1) through the second end G1 (i.e. the grounding end G1) in common, and the adjacent parallel stages 4 are connected to the grounding inductor 2 (LG 2) through the second end G1 (i.e. the grounding end G1) in common, respectively, and the adjacent parallel stages 4 and the grounding inductor 2 (LG 2) are connected to the common through the second end G1 (i.e. the grounding end G2) in fig. 2).

Through the arrangement mode, on one hand, the use quantity of the ground inductance 052 can be reduced, and the quality factor of the ground inductance 052 is improved so as to improve the out-of-band suppression effect of the filter; on the other hand, since the parallel stage 051 includes a plurality of resonators connected in series or in parallel, by combining the parallel stages 051 in two groups, parallel resonant circuits with different resonant frequencies can be formed, and the parallel resonant circuits with different resonant frequencies can form scattered transmission zeros (only by setting different frequencies or capacitance values of the two parallel resonant circuits) outside the band, thereby improving the out-of-band suppression; the 5 parallel stages 051 are connected with different grounding inductors 052 in two groups, so that an inductance-capacitance circuit (LC circuit) is formed between each parallel stage 051 and the corresponding grounding inductor 052, and the LC circuit can enhance the out-of-band suppression effect of the filter, so that the formation quantity of the LC circuits is increased in the filter while the use quantity of the grounding inductors 052 is reduced, and the out-of-band suppression effect of the filter is the best.

As can be seen, in the topology structure provided by the embodiment of the application, the number of the serial stages 041 of the serial branch 04 is set to 4, the number of the parallel stages of the parallel branch 05 is set to 5, so that the number of the parallel stages 051 is more than that of the serial stages 041, the number of the parallel stages 051 is increased, the out-of-band rejection of the filter using the topology structure can be improved, the out-of-band rejection effect of the filter is improved, the specific numbers of the serial stages 041 and the parallel stages 051 are set, the out-of-band rejection and the insertion loss of the filter can be simultaneously considered, the out-of-band rejection and the insertion loss are more balanced, one of the out-of-band rejection and the insertion loss caused by unreasonable number setting is avoided, and the other is poor; furthermore, in the topology structure provided by the embodiment of the present utility model, the second ends of at least two parallel stages 051 are connected to the same ground inductor 052, so that the connection number of the ground inductor 052 in the topology structure can be reduced, and the inductance value generated by the ground inductor 052 can be reduced due to the proportional relationship between the inductance value of the ground inductor 052 and the use number of the ground inductor 052, and the inductance value of the ground inductor 052 and the loss value of the inductance are proportional relationship, so that the loss of the ground inductor 052 can be reduced, the quality factor of the filter can be improved, and the passband insertion loss of the filter can be improved.

Therefore, the technical scheme provided by the embodiment of the application realizes that the out-of-band rejection and the insertion loss of the filter are balanced while improving the out-of-band rejection effect of the filter through the arrangement of the serial stages 041 and the parallel stages 051, so that the out-of-band rejection and the insertion loss are more balanced, and on the other hand, the connection quantity of the grounding sense can be reduced through the connection of the second ends of at least two parallel stages 051 to the same grounding sense, and then the total inductance value generated by the grounding sense is reduced, so that the loss of the grounding sense can be reduced, the quality factor of the filter is improved, and the passband insertion loss of the filter is improved.

In a specific embodiment, please continue to refer to fig. 2-8, in order to further eliminate the influence of the capacitor formed in the topology structure, to achieve matching of the capacitor, the serial branch 04 of the topology structure provided in this embodiment of the present application may further include at least one of an input serial inductor 042 and an output serial inductor 043, where the input serial inductor 042 is connected between the input port 01 of the topology structure and the first connection node of the connection node, and the output serial inductor 043 is connected between the output port 02 of the topology structure and the fifth connection node of the connection node.

It is to be readily understood that the first connection node of the connection nodes described herein refers to the connection node closest to the input port 01 after the 4 serial stages 041 are connected in sequence; the fifth connection node of the connection nodes refers to the connection node which is closest to the input/output port 02 after the 4 serial stages 041 are connected in sequence; the "the series leg 04 may further include at least one of the input series inductance 042 and the output series inductance 043" described herein includes: the series branch 04 includes only the input series inductance 042, only the output series inductance 043, and both the input series inductance 042 and the output series inductance 043.

Specifically, if the inductance value is too small, the elimination effect on the capacitance is limited, the capacitance of the circuit is large, and better impedance matching cannot be realized; the inductance value is too large, the circuit inductance is large, and the good impedance matching can not be realized. Thus, in one embodiment, the input series inductance may have an inductance value in the range of 0.5nH to 5nH.

In another embodiment, the output series inductor may have an inductance value in the range of 0.5nH-5nH for the same reasons as previously described.

In this way, by setting at least one of the input series inductor 042 and the output series inductor 043 in the series branch 04, not only the corresponding capacitance can be eliminated, but also the series inductance required to be matched is smaller than the parallel inductance required to be matched when one end of the input series inductor 042 is connected with the input port 01, the other end is grounded, and the output series inductor 043 is connected with the output port 02, and compared with the other end which is grounded, the required inductance value of the inductance is smaller, because the topological structure can be equivalent to a capacitance network structure, and comprises a series equivalent capacitance and a parallel equivalent capacitance to the ground, the series equivalent capacitance is relatively larger, and the capacitance-inductance matching is required to ensure that the inductance-capacitance product is a constant, therefore, for the same frequency, the series equivalent capacitance is larger than the parallel equivalent capacitance required to be matched, and the series inductance required to be matched is smaller than the parallel inductance required to be matched, so that the elimination effect on the capacitance can be realized by only needing inductance with smaller inductance value, and easy integration; of course, it is easy to understand that when the input series inductor 042 and the output series inductor 043 are simultaneously set, the elimination of the capacitance can be better realized at the input end and the output end, and the performance of the filter using the topological structure is improved.

In order to obtain a better capacitance cancellation effect under the same inductance value, in a specific embodiment, when the topology structure includes the input series inductors 042, the number of the input series inductors 042 may be at least two, and each input series inductor is connected end to end in sequence.

When the sum of the inductance values of the plurality of input series inductors 042 with small inductance values is equal to the inductance value of the input series inductor 042 with large inductance value, the capacitance eliminating effect generated by the plurality of input series inductors 042 with small inductance values is better than the capacitance eliminating effect generated by the input series inductor 042 with large inductance value, so that the plurality of input series inductors 042 can be arranged to obtain better capacitance eliminating effect when the inductance values are the same.

In another embodiment, for the same reasons as described above, when the topology includes the output series inductor 043, the number of the output series inductors may be at least two, and each of the output series inductors is connected in order from the beginning to the end.

In another specific implementation manner, please refer to fig. 9, fig. 9 is an eighth structural schematic diagram of a topology structure of a filter provided by an embodiment of the present utility model, where the topology structure provided by the embodiment of the present application further includes:

And the metal connection structure 06 is connected between the second end of the parallel stage 051 and the ground inductance 052.

The arrangement of the metal connecting structure 06 can more flexibly adjust the zero point of out-of-band suppression, and is helpful for further improving the suppression level at the required frequency band.

Referring to fig. 10, fig. 10 is a schematic structural diagram of a resonator of a filter according to an embodiment of the utility model.

In a specific implementation manner, the parallel stage 051 and the series stage 041 of the topology structure provided in the embodiments of the present application each include a resonator 1, where the resonator 1 includes:

an upper electrode 10 having a thickness in the range of 250nm to 400nm;

a piezoelectric layer 11 having a thickness in the range of 0.6 μm to 1 μm;

the lower electrode 12 has a thickness in the range of 250nm to 400nm.

Of course, as shown in the drawing, the lower electrode 12 is located on the substrate 14, the piezoelectric layer 11 covers the lower electrode 12, the upper electrode 10 covers the piezoelectric layer 11, and a mirror 13 may be provided between the lower electrode 12 and the substrate 14.

During operation of the resonator 1, bulk acoustic waves are excited in the piezoelectric layer 11 by applying radio frequency signals to the lower electrode 12 and the upper electrode 10, thereby completing resonance.

The substrate 14 is used to provide a process platform for the fabrication of bulk acoustic wave resonators. The substrate 14 may be a semiconductor material substrate such as single crystal silicon, gallium arsenide, sapphire, quartz, silicon carbide, SOI, or an inorganic material substrate such as glass, an organic material substrate such as resin, or a single substrate of any type or a composite substrate having a plurality of layers of a plurality of materials. In a specific embodiment, the substrate 14 is a wafer-level substrate, and by manufacturing the resonator 1 on a wafer, the process cost can be reduced, and mass production can be realized, which is beneficial to improving the reliability of the resonator and improving the manufacturing efficiency.

The substrate 14 has a piezoelectric acoustic resonance stack formed thereon, and specifically, the piezoelectric acoustic resonance stack includes a lower electrode 12, a piezoelectric layer 11, and an upper electrode 10, which are sequentially stacked from bottom to top.

In some embodiments, the resonator also comprises a mirror 13 as shown in the figures. The substrate 14, the reflecting mirror 13, the lower electrode 12, the piezoelectric layer 11, and the upper electrode 10 are stacked in this order, and overlapping portions of the reflecting mirror 13, the lower electrode 12, the piezoelectric layer 11, and the upper electrode 10 collectively form an effective region of the resonator.

The reflecting mirror 13 is used as a reflecting structure for reflecting the radio frequency signals in the sandwich structure of the upper electrode/piezoelectric layer/upper electrode back to form a high-Q-value resonant structure, and specifically, the reflecting mirror 13 has larger acoustic impedance difference with the structures of the lower electrode 12, the piezoelectric layer 11, the upper electrode 10 and the like, and can reflect the radio frequency signals in the resonator back to form resonance.

As an example, the reflecting mirror 13 is an air cavity, the reflecting mirror 13 is located below the lower electrode 12, a recess is formed on a surface of the substrate 14, which is close to the lower electrode 12, and the reflecting mirror 13 is a cavity surrounded by the lower electrode 12 and the recess. It will be appreciated that the mirror 13 may also be a bragg reflective layer or other multi-layer structure or the like for achieving an effective reflection of the acoustic signal.

The lower electrode 12, also referred to as a bottom electrode, is positioned on the substrate 14, at least partially covering the substrate 14. The material of the lower electrode 12 may be a metal material such as molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium, or an alloy or a composite structure formed of at least two of the foregoing metals.

The piezoelectric layer 11 includes, but is not limited to, any piezoelectric material such as aluminum nitride, aluminum nitride doped with rare earth elements, zinc oxide, PZT, and the like. The lower electrode 12 and the mirror 13 may include 1 or more layers of insulating materials such as silicon oxide, silicon nitride, aluminum nitride doped with rare earth elements, and the like.

The upper electrode 10 covers the piezoelectric layer 11, and the material thereof is also a metal material, including but not limited to any metal material such as molybdenum, platinum, tungsten, aluminum, titanium, etc., and may be a combination of various materials and a composite material.

Setting the thickness range of the upper electrode 10 of the resonator to 250nm-400nm, the thickness range of the piezoelectric layer 11 to 0.6 μm-1 μm, and the thickness range of the lower electrode 12 to 250nm-400nm, specific frequency range and bandwidth characteristics can be obtained, and the thicknesses of the three-layer structure are relatively balanced, thereby improving the performance indexes such as loss, bandwidth, and the like of the filter.

As mentioned above, each parallel stage 051 and each series stage 041 are connected by at least one of parallel connection and series connection of the resonators 1, for clarity of explanation of the specific connection, please refer to fig. 11-15, for understanding of the series connection, wherein fig. 11 is a schematic diagram of a first structure of the series connection of the resonators of the filter according to the embodiment of the present utility model; fig. 12 is a second schematic diagram of a series connection of resonators of a filter according to an embodiment of the present utility model; fig. 13 is a schematic diagram of a third structure in which resonators of a filter according to an embodiment of the present utility model are connected in series; fig. 14 is a fourth schematic diagram of a series connection of resonators of a filter according to an embodiment of the present utility model; fig. 15 is a schematic view of a fifth structure in which resonators of a filter according to an embodiment of the present utility model are connected in series; fig. 16 is a schematic diagram of a sixth configuration of a series connection of resonators of a filter according to an embodiment of the present utility model.

As shown in the figure, the resonator 1 includes a first resonator and a second resonator connected in series, and the series connection manner of the resonator 1 may include:

the upper electrode 10 of the first resonator is connected to the upper electrode 10 of the second resonator;

The lower electrode 12 of the first resonator is connected to the lower electrode 12 of the second resonator;

the lower electrode 12 of the first resonator is connected to the upper electrode 10 of the second resonator by a conductive structure 15 penetrating the piezoelectric layer 11; and/or

The upper electrode 10 of the first resonator is connected to the lower electrode 12 of the second resonator by a conductive structure 15 penetrating the piezoelectric layer 11.

Specifically, the connection of the upper electrode 10 of the first resonator and the upper electrode 10 of the second resonator may be in the manner shown in fig. 11 and 12, in which the upper electrode 10 may be connected by a unitary structure, the piezoelectric layers 11 may be separate from each other or may be a single piece of piezoelectric layers 11 connected to each other, and when the first resonator is closer to the input port 01, the transmission path of the signal is the lower electrode 12 of the first resonator, the piezoelectric layers 11, the upper electrode 10, the piezoelectric layers 11, and the lower electrode 12 of the second resonator.

The connection of the lower electrode 12 of the first resonator and the lower electrode 12 of the second resonator may be in the manner shown in fig. 13 and 14, wherein the lower electrode 12 may be connected by a unitary structure, the piezoelectric layers 11 may be separated from each other or may be a single piece of piezoelectric layers 11 connected to each other, and when the first resonator is closer to the input port 01, the transmission path of the signal is the upper electrode 10 of the first resonator, the piezoelectric layers 11, the lower electrode 12, the piezoelectric layers 11, and the upper electrode 10 of the second resonator.

The connection between the lower electrode 12 of the first resonator and the upper electrode 10 of the second resonator through the conductive structure 15 penetrating the piezoelectric layer 11 may be as shown in fig. 15, wherein the conductive structure 15 is formed in a through hole formed in the piezoelectric layer 11, and the lower electrode 12 of the first resonator and the upper electrode 10 of the second resonator are both extended to the position of the conductive structure 15 and electrically connected to the conductive structure 15. When the first resonator is closer to the input port 01, the transmission path of the signal is the upper electrode 10 of the first resonator, the piezoelectric layer 11, the lower electrode 12 of the first resonator, the conductive structure 15, the upper electrode 10 of the second resonator, the piezoelectric layer 11, and the lower electrode 12 of the second resonator.

The connection between the upper electrode 10 of the first resonator and the lower electrode 12 of the second resonator through the conductive structure 15 penetrating the piezoelectric layer 11 may be as shown in fig. 16, wherein the conductive structure 15 is formed in a through hole formed in the piezoelectric layer 11, and the upper electrode 10 of the first resonator and the lower electrode 12 of the second resonator are both extended to the position of the conductive structure 15 and electrically connected to the conductive structure 15. When the first resonator is closer to the input port 01, the transmission path of the signal is the lower electrode 12 of the first resonator, the piezoelectric layer 11, the upper electrode 10 of the first resonator, the conductive structure 15, the lower electrode 12 of the second resonator, the piezoelectric layer 11, and the upper electrode 10 of the second resonator.

Through the various series connection modes, the series connection requirements of different resonators under various conditions can be met, and the resonators can be conveniently connected in series.

In addition to the serial connection, please refer to fig. 17 and fig. 18, fig. 17 is a schematic diagram showing a first structure of parallel connection of resonators of a filter according to an embodiment of the present utility model; fig. 18 is a first schematic diagram of parallel connection of resonators of a filter according to an embodiment of the present utility model

As shown in the figure, the resonator 1 includes a first resonator and a second resonator connected in parallel, and the parallel connection manner of the resonator 1 includes:

the upper electrode 10 of the first resonator is connected with the upper electrode 10 of the second resonator, and the lower electrode 12 of the first resonator is connected with the lower electrode 12 of the second resonator (referred to as a first parallel connection for convenience of description); and/or

The upper electrode 10 of the first resonator is connected to the lower electrode 12 of the second resonator through a conductive structure 15 penetrating the piezoelectric layer 11, and the lower electrode 12 of the first resonator is connected to the upper electrode 10 of the second resonator through a conductive structure 15 penetrating the piezoelectric layer (referred to as a second parallel connection mode for convenience of description).

Specifically, as shown in fig. 17, the first parallel connection manner is shown, in which the upper electrode 10 may be connected by a monolithic structure, the piezoelectric layers 11 may be separated from each other, or may be a monolithic piezoelectric layer 11 connected to each other, and the lower electrode 12 may be connected by a monolithic structure, and when the upper electrode 10 is closer to the input port 01, the signal transmission path is: the upper electrode 10 of the first resonator, the piezoelectric layer 11 and the lower electrode 12 of the first resonator, and the upper electrode 10 of the second resonator, the piezoelectric layer 11 and the lower electrode 12 of the second resonator.

The second parallel connection is shown in fig. 18, in which the dotted lower electrode 12 and the solid lower electrode 12 are not different in thickness, but are not shown for the sake of showing the connection relationship, and the connection relationship is not shown because the solid and the dotted lines overlap. The conductive structure 15 is formed in a through hole formed in the piezoelectric layer 11, the lower electrode 12 of the first resonator and the upper electrode 10 of the second resonator extend to the position of the conductive structure 15 and are electrically connected to the conductive structure 15, and the upper electrode 10 of the first resonator and the lower electrode 12 of the second resonator also extend to the position of the conductive structure 15 and are electrically connected to the conductive structure 15. When the upper electrode 10 is closer to the input port 01, the transmission paths of signals are two of the upper electrode 10 of the first resonator, the conductive structure 15 of the piezoelectric layer 11, and the lower electrode 12 of the second resonator, and the upper electrode 10 of the second resonator, the conductive structure 15 of the piezoelectric layer 11, and the lower electrode 12 of the first resonator.

Through the various parallel connection modes, the parallel connection requirements of different resonators under various conditions can be met, and the resonators can be conveniently connected in parallel.

Of course, the embodiment of the present application further provides a filter, including a topology structure as in any one of the foregoing embodiments, so that on one hand, by setting the number of the series-connection stages 041 and the parallel-connection stages 051, it is possible to achieve that out-of-band suppression and insertion loss of the filter are considered while improving out-of-band suppression effect of the filter, so that out-of-band suppression and insertion loss are more balanced, on the other hand, by connecting the second ends of at least two parallel-connection stages 051 to the same ground inductance, the number of connections to the ground inductance can be reduced, further the total inductance value generated to the ground inductance is reduced, the loss to the ground inductance is reduced, the quality factor of the filter is improved, and the passband insertion loss of the filter is improved.

Referring to fig. 19, fig. 19 is a transmission graph of a filter according to an embodiment of the present utility model, wherein the horizontal axis represents frequency, the vertical axis represents a suppression value, and the frequency region represented by the dashed box 7 refers to a passband.

As shown in the figure, in a specific implementation manner, the filter provided in the embodiment of the present application may implement a passband center frequency range of 2.3GHz-2.7GHz, so as to meet the use requirement of the filter.

The passband center frequency is defined as the sum of the leftmost frequency and the rightmost frequency of the passband divided by 2, and is a single frequency point, where the range of the passband center frequency is 2.3GHz-2.7GHz, which means that the single point frequency of the passband center frequency can be located at any point between 2.3GHz and 2.7GHz, and the passband is the range shown by the dashed box 7 in fig. 19.

In a specific implementation manner, the filter with the topological structure shown in any embodiment further has the characteristic that the insertion loss worst value in the passband is-2.5 dB, has lower insertion loss, and ensures that the performance of the filter meets the performance requirement of signal transmission.

In another specific implementation manner, the filter with the topological structure shown in any embodiment further has the characteristic that the worst value of passband insertion loss fluctuation is-1.8 dB, and due to the arrangement of the structure, the filter has lower passband insertion loss fluctuation, and the performance of the filter is ensured to meet the performance requirement.

In another specific embodiment, the filter having the topology shown in any of the foregoing embodiments further has the following features: the suppression value of the filter is smaller than-40 dB in the range from 250MHz reduction of the center frequency of the passband to 150MHz reduction of the center frequency of the passband; the suppression value of the filter is smaller than-50 dB in the range from 150MHz reduction of the center frequency of the passband to 90MHz reduction of the center frequency of the passband; the suppression value of the filter is smaller than-45 dB in the range from 90MHz reduction of the center frequency of the passband to 75MHz reduction of the center frequency of the passband; the suppression value of the filter is smaller than-50 dB in the range from 65MHz to 110MHz of the center frequency of the passband; the suppression value of the filter is smaller than-45 dB in the range from 110MHz to 130 MHz; in the range from 130MHz to 250MHz, the suppression value of the filter is smaller than-40 dB, so that the filter provided by the utility model has a good out-of-band suppression effect.

In addition, the utility model also provides communication equipment comprising the filter in the previous embodiment.

The foregoing describes a number of embodiments provided by embodiments of the present application, and the various alternatives presented by the various embodiments may be combined, cross-referenced, with each other without conflict, extending beyond what is possible, all of which may be considered embodiments disclosed and disclosed by embodiments of the present application.

Although the embodiments of the present application are disclosed above, the present application is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the utility model, and the scope of the utility model shall be defined by the appended claims.

Claims (17)

1. A topology, adapted for use in a filter, comprising:

the series branch comprises 4 series stages, and the connecting nodes of the series stages are sequentially connected end to end;

the parallel branch circuit comprises 5 parallel stages, wherein the first end of each parallel stage is respectively connected with the connection node of each serial stage, the second end of each parallel stage is connected with the grounding inductance of the parallel branch circuit, and the second ends of at least two parallel stages are connected with the same grounding inductance.

2. The topology of claim 1, wherein the number of said inductors to ground is 2, the second ends of two of said parallel stages are connected to one of said inductors to ground, and the second ends of three of said parallel stages are connected to another of said inductors to ground.

3. The topology of claim 1, wherein said series leg further comprises at least one of an input series inductance connected between an input port of said topology and a first connection node of said connection nodes, and an output series inductance connected between an output port of said topology and a fifth connection node of said connection nodes.

4. A topology as recited in claim 3, wherein the number of said input series inductances is at least two, each of said input series inductances being connected end-to-end in turn.

5. A topology as recited in claim 3, wherein the number of said output series inductances is at least two, each of said output series inductances being connected end-to-end in turn.

6. A topology as recited in claim 3, wherein the input series inductor has an inductance value in the range of 0.5nH-5nH.

7. A topology as recited in claim 3, wherein the output series inductor has an inductance value in the range of 0.5nH-5nH.

8. The topology of any of claims 1-7, further comprising:

and the metal connection structure is connected between the second end of the parallel stage and the ground inductance.

9. The topology of any of claims 1-7, wherein the parallel stage and the series stage each comprise a resonator comprising:

an upper electrode with a thickness ranging from 250nm to 400nm;

a piezoelectric layer having a thickness in the range of 0.6 μm to 1 μm;

the lower electrode has a thickness in the range of 250nm to 400nm.

10. The topology of claim 9, wherein said resonator comprises a first resonator and a second resonator connected in series, said resonators being connected in series in a manner comprising:

the upper electrode of the first resonator is connected with the upper electrode of the second resonator;

the lower electrode of the first resonator is connected with the lower electrode of the second resonator;

the lower electrode of the first resonator is connected with the upper electrode of the second resonator through a conductive structure penetrating through the piezoelectric layer; and/or

The upper electrode of the first resonator is connected to the lower electrode of the second resonator through a conductive structure penetrating the piezoelectric layer.

11. The topology of claim 9, wherein said resonator comprises a first resonator and a second resonator connected in parallel, said resonators being connected in parallel in a manner comprising:

the upper electrode of the first resonator is connected with the upper electrode of the second resonator, and the lower electrode of the first resonator is connected with the lower electrode of the second resonator; and/or

The upper electrode of the first resonator is connected with the lower electrode of the second resonator through a conductive structure penetrating the piezoelectric layer, and the lower electrode of the first resonator is connected with the upper electrode of the second resonator through a conductive structure penetrating the piezoelectric layer.

12. A filter comprising a topology according to any of claims 1-11.

13. The filter of claim 12, wherein the filter has a passband center frequency in the range of 2.3GHz-2.7GHz.

14. The filter of claim 12 wherein the insertion loss worst value within the filter passband is-2.5 dB.

15. The filter of claim 12 wherein the filter has a passband insertion loss ripple with a worst value of-1.8 dB.

16. The filter of claim 12, wherein the filter is configured to filter the filter,

the suppression value of the filter is smaller than-40 dB in the range from 250MHz reduction of the center frequency of the passband to 150MHz reduction of the center frequency of the passband;

the suppression value of the filter is smaller than-50 dB in the range from 150MHz reduction of the center frequency of the passband to 90MHz reduction of the center frequency of the passband;

the suppression value of the filter is smaller than-45 dB in the range from 90MHz reduction of the center frequency of the passband to 75MHz reduction of the center frequency of the passband;

the suppression value of the filter is smaller than-50 dB in the range from 65MHz to 110MHz of the center frequency of the passband;

the suppression value of the filter is smaller than-45 dB in the range from 110MHz to 130 MHz;

the suppression value of the filter is less than-40 dB in the range from 130MHz increase in the center frequency of the passband to 250MHz increase in the center frequency of the passband.

17. A communication device comprising a filter according to any of claims 10-15.