CN106301274A - A kind of band filter - Google Patents
A kind of band filter Download PDFInfo
- Publication number
- CN106301274A CN106301274A CN201610671262.XA CN201610671262A CN106301274A CN 106301274 A CN106301274 A CN 106301274A CN 201610671262 A CN201610671262 A CN 201610671262A CN 106301274 A CN106301274 A CN 106301274A
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- China
- Prior art keywords
- coupling coil
- band filter
- coupling
- coil
- coupled pair
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 230000008878 coupling Effects 0.000 claims abstract description 142
- 238000010168 coupling process Methods 0.000 claims abstract description 142
- 238000005859 coupling reaction Methods 0.000 claims abstract description 142
- 230000002265 prevention Effects 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 9
- 239000003989 dielectric material Substances 0.000 claims description 7
- 239000000758 substrate Substances 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 4
- 229910000859 α-Fe Inorganic materials 0.000 claims description 4
- 230000033228 biological regulation Effects 0.000 claims description 2
- 238000010276 construction Methods 0.000 abstract description 6
- 230000001629 suppression Effects 0.000 abstract description 5
- 238000005516 engineering process Methods 0.000 description 3
- 238000003780 insertion Methods 0.000 description 3
- 230000037431 insertion Effects 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 239000004020 conductor Substances 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005538 encapsulation Methods 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000006247 magnetic powder Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000004899 motility Effects 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
- H03H7/01—Frequency selective two-port networks
- H03H7/0153—Electrical filters; Controlling thereof
- H03H7/0161—Bandpass filters
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
- H03H7/01—Frequency selective two-port networks
- H03H7/0138—Electrical filters or coupling circuits
Landscapes
- Filters And Equalizers (AREA)
Abstract
The invention discloses a kind of band filter, including: coupled pair, first coupled pair comprises the first coupling coil and the second coupling coil, second coupled pair comprises the 3rd coupling coil and the 4th coupling coil, 3rd coupled pair comprises the 5th coupling coil and the 6th coupling coil, and the 4th coupled pair comprises the 7th coupling coil and the 8th coupling coil.This band filter, it is not necessary to use electric capacity and the inductance element of high q-factor, and at low-frequency stop band frequency and high frequency stopband frequency, there is trap characteristic, specific frequency can be carried out trap suppression.Owing to without using electric capacity and inductance element, therefore reducing the complexity of structure, and without taking bigger chip area, there is simple in construction, with low cost, the advantage that is easily achieved.
Description
Technical field
The present invention relates to technical field of radio frequency integrated circuits, particularly relate to a kind of band filter.
Background technology
RF IC is the novel device of one occurred along with the improvement of IC technique since the mid-90 in 20th century
Part.Band filter is basic components conventional in RF IC, is used for by the frequency component in a certain frequency range,
And the frequency component of other frequency range is decayed to the wave filter of reduced levels.In high performance band filter requires passband
Insertion loss is low, flatness good, and in stopband, degree of suppression is high, and in view of reality application, usually requires that band filter has
Less chip size and relatively low cost.
Fig. 1 is the structure chart of the band filter used in prior art.As it is shown in figure 1, this band filter is by electricity
Sense and three rank band filters of electric capacity composition, comprise 3 electric capacity C1, C2, C3,3 inductance L1, L2, L3.The first of electric capacity C1
Hold the first prevention at radio-frequency port RF1 as band filter.Second end of electric capacity C3 is as the second prevention at radio-frequency port of band filter
RF2。
Based on the band filter shown in Fig. 1, when the parameter of electric capacity, inductance is respectively C1=80.37fF, C2=
12.73pF, C3=80.37fF, L1=15.92nH, L2=100.5pH, L3=15.92nH, it is possible to achieve passband is 4.2-
The band filter of 4.7GHz.Above-mentioned three rank band filters to realize that logical in-band insertion loss is low, flatness good, presses down in stopband
System is high, and this just requires that electric capacity and inductance have higher quality factor (Q-value).Half body technology realizes C1, C3, L1, L2,
The such value of L3 and the element with high q-factor are extremely difficult.In order to realize the lowest capacitance of C1, C3 and high q-factor
Electric capacity, it usually needs use the mode of multiple capacitances in series equivalence, add the complexity of structure；In order to realize L1, L3 so
High inductance value and the inductance of high q-factor, it usually needs occupy the biggest chip area；In order to realize the lowest inductance value of L2 and high Q
The inductance of value, is typically only capable to rely on the bonding gold wire in encapsulation to realize, and precision is difficult to ensure that；In order to improve stopband further
Interior degree of suppression, it usually needs the band filter of higher order, this will comprise more electric capacity and inductance element, it is achieved difficulty will more
High.
As can be seen here, how providing a kind of simple in construction, band filter with low cost, that be easily achieved is this area skill
Art personnel's problem demanding prompt solution.
Summary of the invention
It is an object of the invention to provide a kind of band filter, there is simple in construction, with low cost, the spy that is easily achieved
Property.
For solving above-mentioned technical problem, the present invention provides a kind of band filter, including: coupled pair, the first coupling
Coil is to comprising the first coupling coil 31 and the second coupling coil 32, and the second coupled pair comprises the 3rd coupling coil 33 and
Four coupling coils 34, the 3rd coupled pair comprises the 5th coupling coil 35 and the 6th coupling coil 36, the 4th coupled pair
Comprise the 7th coupling coil 37 and the 8th coupling coil 38；
First end of described first coupling coil 31 is connected, as described band with the first end of described 4th coupling coil 34
First prevention at radio-frequency port RF1 of bandpass filter, the of the second end of described first coupling coil 31 and described 3rd coupling coil 33
First end of two ends, the first end of described 5th coupling coil 35 and described 7th coupling coil 37 connects；
First end of described second coupling coil 32 and the first end ground connection of described 3rd coupling coil 33, described second coupling
Second end of zygonema circle 32 and the second end of described 4th coupling coil 34, the first end of described 6th coupling coil 36 and described
First end of the 8th coupling coil 38 connects；
Second end of described 5th coupling coil 35 is as the second prevention at radio-frequency port RF2 of described band filter；
Second end of described 6th coupling coil 36 and the second end ground connection of described 7th coupling coil 37；
Second end open circuit of described 8th coupling coil 38.
Preferably, the second end of described first coupling coil 31 and the second end of described 3rd coupling coil 33 are by first
Electric capacity is connected with the first end of described 5th coupling coil 35 and the first end of described 7th coupling coil 37.
Preferably, the second end of described second coupling coil 32 and the second end of described 4th coupling coil 34 are by second
Electric capacity is connected with the first end of described 6th coupling coil 36 and the first end of described 8th coupling coil 38.
Preferably, the first end of described second coupling coil 32 and the first end of described 3rd coupling coil 33 are by the 3rd
Capacity earth.
Preferably, the second end of described 6th coupling coil 36 and the second end of described 7th coupling coil 37 are by the 4th
Capacity earth.
Preferably, described band filter uses the IPD technique with multi-layer metal wiring and High resistivity substrate.
Preferably, the resistivity of described High resistivity substrate is more than 1000ohm cm.
Preferably, the dielectric layer of described IPD technique is the dielectric material with regulation pcrmeability.
Preferably, described dielectric material is Ferrite Material.
The present invention provides a kind of band filter, is made up of 4 coupled pairs, the first coupling coil and the second coupling line
Circle constitutes first coupled pair, the 3rd coupling coil and the 4th coupling coil and constitutes second coupled pair, the 5th coupling
Zygonema circle and the 6th coupling coil constitute the 3rd coupled pair, and the 7th coupling coil and the 8th coupling coil constitute the 4th
Coupled pair.First end of the first end of the first coupling coil and the 4th coupling coil connects, as the of band filter
One prevention at radio-frequency port.Second end of the 5th coupling coil is as the second prevention at radio-frequency port of band filter.The of second coupling coil
The three-terminal link of one end and the 3rd coupling coil ground connection, the second end of the 6th coupling coil and the second of the 7th coupling coil
End connects and ground connection, the second end open circuit of the 8th coupling coil.Second end of the first coupling coil, the second of the 3rd coupling coil
First end of end, the first end of the 5th coupling coil and the 7th coupling coil connects.Second end of the second coupling coil, the 4th coupling
First end of the second end of zygonema circle, the first end of the 6th coupling coil and the 8th coupling coil connects.
Compared with prior art, the band filter that the present invention provides, it is not necessary to use electric capacity and the inductance unit of high q-factor
Part, and at low-frequency stop band frequency and high frequency stopband frequency, there is trap characteristic, specific frequency can be carried out trap suppression.By
In without using electric capacity and inductance element, therefore reduce the complexity of structure, and without taking bigger chip area, tool
There are simple in construction, with low cost, the advantage that is easily achieved.
Accompanying drawing explanation
In order to be illustrated more clearly that the embodiment of the present invention, the accompanying drawing used required in embodiment will be done simply below
Introduce, it should be apparent that, the accompanying drawing in describing below is only some embodiments of the present invention, for ordinary skill people
From the point of view of Yuan, on the premise of not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the structure chart of the band filter used in prior art；
The structure chart of a kind of band filter that Fig. 2 provides for the present invention.
Detailed description of the invention
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete
Describe, it is clear that described embodiment is only a part of embodiment of the present invention rather than whole embodiment wholely.Based on this
Embodiment in invention, those of ordinary skill in the art are not under making creative work premise, and obtained is every other
Embodiment, broadly falls into scope.
The core of the present invention is to provide a kind of band filter, has simple in construction, with low cost, the spy that is easily achieved
Property.
In order to make those skilled in the art be more fully understood that the present invention program, below in conjunction with the accompanying drawings and detailed description of the invention
The present invention is described in further detail.
The structure chart of a kind of band filter that Fig. 2 provides for the present invention.
As in figure 2 it is shown, include 4 coupled pairs, the first coupled pair comprises the first coupling coil 31 and the second coupling
Zygonema circle 32, the second coupled pair comprises the 3rd coupling coil 33 and the 4th coupling coil 34, and the 3rd coupled pair comprises
5th coupling coil 35 and the 6th coupling coil 36, the 4th coupled pair comprises the 7th coupling coil 37 and the 8th coupling coil
38.Wherein, the first end of the first end of the first coupling coil 31 and the 4th coupling coil 34 connects, as the of band filter
One prevention at radio-frequency port RF1；Second end of the 5th coupling coil 35 is as the second prevention at radio-frequency port RF2 of band filter；First coupling
Second end of coil 31 and the second end of the 3rd coupling coil 33, the first end of the 5th coupling coil 35 and the 7th coupling coil 37
First end connect；First end of the second coupling coil 32 and the first end ground connection of the 3rd coupling coil 33, the second coupling coil
Second end of 32 and the of the second end of the 4th coupling coil 34, the first end of the 6th coupling coil 36 and the 8th coupling coil 38
One end connects；Second end of the 6th coupling coil 36 and the second end ground connection of the 7th coupling coil 37；8th coupling coil 38
Second end open circuit.
In a specific embodiment, the second end of the second end of the first coupling coil 31 and the 3rd coupling coil 33 is by the
First end of one electric capacity and the first end of the 5th coupling coil 35 and the 7th coupling coil 37 connects.The of second coupling coil 32
Second end of two ends and the 4th coupling coil 34 is by the second electric capacity and the first end of the 6th coupling coil 36 and the 8th coupling line
First end of circle 38 connects.Connected the purpose that can reach decoupling by electric capacity, be prevented effectively between coupling coil is the most dry
Disturb, improve the stability of band filter work.
First end of the second coupling coil 32 and the first end of the 3rd coupling coil 33 are by the 3rd capacity earth.6th coupling
Second end of zygonema circle 36 and the second end of the 7th coupling coil 37 are by the 4th capacity earth.Wherein electric capacity shields,
Prevent instantaneous surge voltage or electric current excessive damage components and parts.
Implementing of above-mentioned band filter, can use be manufactured in substrate, IPD chip or other any suitably half
Coupling coil on conductor chip.As a kind of optimal way, in the present invention, band filter uses and has multi-layer metal wiring
And the IPD technique of High resistivity substrate.Wherein, multi-layer metal wiring has advantages such as packaging density height, little, the light weight of volume, each group
Line between part reduces, and improves reliability, and along with the increase of the wiring number of plies, makes design more motility.High resistivity substrate
Resistivity more than 1000ohm cm, there is good microwave device performance, the insertion loss of device can be reduced, improve work
Make efficiency.
The dielectric layer of IPD technique uses the dielectric material with higher magnetic permcability.Wherein, the kind of dielectric material has multiple
Such as stalloy, ferrum nickel magnetic powder core, Ferrite Material etc..As a kind of optimal way, the dielectric material used in the present invention is ferrum
Ferrite, can improve the coefficient of coup of coupled pair, improves the performance of band filter and reduces its physical size.Need
It is noted that the present invention is not limited in this material.
The band filter that the present invention provides, it is not necessary to use electric capacity and the inductance element of high q-factor, and at low-frequency stop band
Frequency and high frequency stopband frequency have trap characteristic, specific frequency can be carried out trap suppression.Due to without use electric capacity and
Inductance element, therefore reduces the complexity of structure, and without taking bigger chip area, has simple in construction, cost
Advantage cheap, that be easily achieved.
Above a kind of band filter provided by the present invention is described in detail.In description, each embodiment is adopted
Describing by the mode gone forward one by one, what each embodiment stressed is the difference with other embodiments, each embodiment it
Between identical similar portion see mutually.For device disclosed in embodiment, method disclosed in itself and embodiment
Corresponding, so describe is fairly simple, relevant part sees method part and illustrates.It should be pointed out that, and this technology is led
For the those of ordinary skill in territory, under the premise without departing from the principles of the invention, it is also possible to the present invention is carried out some improvement and
Modifying, these improve and modify in the protection domain also falling into the claims in the present invention.
Claims (9)
1. a band filter, it is characterised in that including: coupled pair, the first coupled pair comprises the first coupling line
Circle 31 and the second coupling coil 32, the second coupled pair comprises the 3rd coupling coil 33 and the 4th coupling coil 34, the 3rd coupling
Zygonema circle is to comprising the 5th coupling coil 35 and the 6th coupling coil 36, and the 4th coupled pair comprises the 7th coupling coil 37 He
8th coupling coil 38；
First end of described first coupling coil 31 is connected with the first end of described 4th coupling coil 34, as the logical filter of described band
First prevention at radio-frequency port RF1 of ripple device, the second end of described first coupling coil 31 and the second end of described 3rd coupling coil 33,
First end of described 5th coupling coil 35 and the first end of described 7th coupling coil 37 connect；
First end of described second coupling coil 32 and the first end ground connection of described 3rd coupling coil 33, described second coupling line
Second end of circle 32 and the second end of described 4th coupling coil 34, first end and the described 8th of described 6th coupling coil 36
First end of coupling coil 38 connects；
Second end of described 5th coupling coil 35 is as the second prevention at radio-frequency port RF2 of described band filter；
Second end of described 6th coupling coil 36 and the second end ground connection of described 7th coupling coil 37；
Second end open circuit of described 8th coupling coil 38.
2. band filter as claimed in claim 1, it is characterised in that the second end of described first coupling coil 31 and described
Second end of the 3rd coupling coil 33 is coupled with first end and the described 7th of described 5th coupling coil 35 by the first electric capacity
First end of coil 37 connects.
3. band filter as claimed in claim 1, it is characterised in that the second end of described second coupling coil 32 and described
Second end of the 4th coupling coil 34 is coupled with first end and the described 8th of described 6th coupling coil 36 by the second electric capacity
First end of coil 38 connects.
4. band filter as claimed in claim 1, it is characterised in that the first end of described second coupling coil 32 is with described
First end of the 3rd coupling coil 33 passes through the 3rd capacity earth.
5. band filter as claimed in claim 1, it is characterised in that the second end of described 6th coupling coil 36 is with described
Second end of the 7th coupling coil 37 passes through the 4th capacity earth.
6. band filter as claimed in claim 1, it is characterised in that described band filter uses has muti-layered metallic
The IPD technique of line and High resistivity substrate.
7. band filter as claimed in claim 6, it is characterised in that the resistivity of described High resistivity substrate is more than
1000ohm·cm。
Band filter the most as claimed in claims 6 or 7, it is characterised in that the dielectric layer of described IPD technique is for having regulation
The dielectric material of pcrmeability.
9. band filter as claimed in claim 8, it is characterised in that described dielectric material is Ferrite Material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610671262.XA CN106301274A (en) | 2016-08-16 | 2016-08-16 | A kind of band filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610671262.XA CN106301274A (en) | 2016-08-16 | 2016-08-16 | A kind of band filter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106301274A true CN106301274A (en) | 2017-01-04 |
Family
ID=57672111
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610671262.XA Pending CN106301274A (en) | 2016-08-16 | 2016-08-16 | A kind of band filter |
Country Status (1)
| Country | Link |
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| CN (1) | CN106301274A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110048735A (en) * | 2017-12-07 | 2019-07-23 | 英飞凌科技股份有限公司 | System and method for radio-frequency filter |
| CN116190947A (en) * | 2022-12-26 | 2023-05-30 | 北京邮电大学 | High-frequency-ratio microwave millimeter wave cross-band filter circuit and chip |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61159715A (en) * | 1985-01-07 | 1986-07-19 | Matsushita Electric Ind Co Ltd | Balun coil |
| JPS6210910A (en) * | 1985-07-05 | 1987-01-19 | Matsushita Electric Ind Co Ltd | Balun coil |
| JPH07321588A (en) * | 1994-05-24 | 1995-12-08 | Ge Yokogawa Medical Syst Ltd | Impedance matching circuit |
| JP2006140765A (en) * | 2004-11-12 | 2006-06-01 | Toko Inc | Balun transformer |
| JP2010021630A (en) * | 2008-07-08 | 2010-01-28 | Nippon Antenna Co Ltd | Wide-band balun |
| WO2010058892A2 (en) * | 2008-11-19 | 2010-05-27 | Electronics And Telecommunications Research Institute | 3-way balun for planar-type double balanced mixer |
| CN204332583U (en) * | 2011-11-04 | 2015-05-13 | 株式会社村田制作所 | Common mode choke and high-frequency electron device |
| CN104767021A (en) * | 2015-05-04 | 2015-07-08 | 中国电子科技集团公司第五十四研究所 | A Broadband Highly Balanced On-Chip Transformer Balun |
-
2016
- 2016-08-16 CN CN201610671262.XA patent/CN106301274A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61159715A (en) * | 1985-01-07 | 1986-07-19 | Matsushita Electric Ind Co Ltd | Balun coil |
| JPS6210910A (en) * | 1985-07-05 | 1987-01-19 | Matsushita Electric Ind Co Ltd | Balun coil |
| JPH07321588A (en) * | 1994-05-24 | 1995-12-08 | Ge Yokogawa Medical Syst Ltd | Impedance matching circuit |
| JP2006140765A (en) * | 2004-11-12 | 2006-06-01 | Toko Inc | Balun transformer |
| JP2010021630A (en) * | 2008-07-08 | 2010-01-28 | Nippon Antenna Co Ltd | Wide-band balun |
| WO2010058892A2 (en) * | 2008-11-19 | 2010-05-27 | Electronics And Telecommunications Research Institute | 3-way balun for planar-type double balanced mixer |
| CN204332583U (en) * | 2011-11-04 | 2015-05-13 | 株式会社村田制作所 | Common mode choke and high-frequency electron device |
| CN104767021A (en) * | 2015-05-04 | 2015-07-08 | 中国电子科技集团公司第五十四研究所 | A Broadband Highly Balanced On-Chip Transformer Balun |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110048735A (en) * | 2017-12-07 | 2019-07-23 | 英飞凌科技股份有限公司 | System and method for radio-frequency filter |
| CN110048735B (en) * | 2017-12-07 | 2023-02-14 | 英飞凌科技股份有限公司 | System and method for radio frequency filter |
| CN116190947A (en) * | 2022-12-26 | 2023-05-30 | 北京邮电大学 | High-frequency-ratio microwave millimeter wave cross-band filter circuit and chip |
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