CN108233912B - Double-pole double-throw radio frequency switch - Google Patents
Double-pole double-throw radio frequency switch Download PDFInfo
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- CN108233912B CN108233912B CN201611149947.4A CN201611149947A CN108233912B CN 108233912 B CN108233912 B CN 108233912B CN 201611149947 A CN201611149947 A CN 201611149947A CN 108233912 B CN108233912 B CN 108233912B
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
Abstract
The invention provides a double-pole double-throw radio frequency switch, which comprises: a first arm (a1) connected between a first radio frequency terminal (RF1) and a first antenna terminal (ANT1), a second arm (a2) connected between the first antenna terminal (ANT1) and a second radio frequency terminal (RF2), a third arm (A3) connected between the second radio frequency terminal (RF2) and a second antenna terminal (ANT2), a fourth arm (a4) connected between the second antenna terminal (ANT2) and a first radio frequency terminal (RF1), a first inductance (L1) and a second inductance (L2) connected in series between the first antenna terminal (ANT1) and the second antenna terminal (ANT 2); the first to fourth arms (A1-A4) are identical in structure, and each arm includes: two capacitors and a switching device, the switching device being connected in series between the two capacitors. Compared with the prior art, the invention has the advantages of low insertion loss, high isolation performance and smaller device volume.
Description
Technical Field
The invention relates to the field of integrated circuits, in particular to a double-pole double-throw radio frequency switch.
Background
As modern communication technologies are increasingly developed towards miniaturization and low power consumption of communication devices, it is required that each component in the communication device be designed in a miniaturized manner, that the size and thickness of the device be controlled, and that the number of components and the power consumption of the components be reduced.
The radio frequency signal input and output module mainly can realize the functions of low-noise amplification of received radio frequency signals, power amplification of transmitted radio frequency signals and the like, and is an indispensable component in radio frequency communication equipment, wherein the double-pole double-throw switch is used for realizing the functions of signal flow direction control and the like of the radio frequency signals. In current microwave communication systems, the power switch generally takes several forms: (1) the PIN diode made of discrete silicon materials is realized by adopting a hybrid circuit, and has the defects of large volume, narrow working frequency and complex control circuit; (2) the gallium arsenide GaAs high electron mobility transistor pHEMT monolithic switch is adopted, and has the characteristics of small size, wide application frequency band and the like, but is not easy to be integrated with other radio frequency circuits in a single chip; (3) the switch adopting the MOS device has the advantages of price, suitability for on-chip integration with other parts of communication circuits, and limited voltage resistance and high power resistance. In addition, the existing power switch also needs to overcome the defects of large insertion loss, non-ideal isolation, large input-output standing wave ratio, long switch response time and the like urgently, and along with the continuous development of modern communication technology and increasingly harsh requirements of people on communication quality, the traditional double-pole double-throw switch cannot meet the requirements of practical use.
Fig. 1 shows a conventional double-pole double-throw rf switch structure. This structure can control the RF signal to be switched between four ports consisting of two RF terminals RF1 and RF2 and two antenna terminals ANT1 and ANT 2. However, since either path must pass through two switching devices, this configuration has the disadvantages of relatively large insertion loss, less than ideal isolation between ports, and limited device applicability.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a double-pole double-throw switch with low insertion loss and high isolation performance and smaller device volume compared with the prior art.
In order to solve the above technical problem, the present invention provides a double-pole double-throw radio frequency switch, including: a first radio frequency end RF1, a second radio frequency end RF2, first to fourth arms A1 to A4, first to third inductors L1 to L3, and first to second antenna ends ANT1 and ANT 2;
the first arm a1 is connected between the first radio frequency terminal RF1 and the first antenna terminal ANT1, the second arm a2 is connected between the first antenna terminal ANT1 and the second radio frequency terminal RF2, the third arm A3 is connected between the second radio frequency terminal RF2 and the second antenna terminal ANT2, the fourth arm a4 is connected between the second antenna terminal ANT2 and the first radio frequency terminal RF1, and the first inductance L1 and the second inductance L2 are connected in series between the first antenna terminal ANT1 and the second antenna terminal ANT 2;
wherein, the first to fourth arms A1-A4 are completely the same in structure, each arm comprises: two capacitors and a switching device, the switching device being connected in series between the two capacitors. When the switching device is turned on, the corresponding arm is turned on; when the switching device is turned off, the corresponding arm is turned off.
In a further improvement, the inductor further comprises a third inductor L3 and a ninth capacitor C9, one end of the third inductor L3 is connected between the first inductor L1 and the second inductor L2, and the other end is internally grounded; the ninth capacitor C9 is connected in parallel with the third inductor L3.
In a further improvement, the switching devices S1-S4 are PMOS, NMOS, HEMT or LDMOS.
When a radio frequency signal passes between the first radio frequency terminal RF1 and the first antenna terminal ANT1, the first arm a1 and the third arm A3 are turned on, and the second arm a2 and the fourth arm a4 are turned off.
When a radio frequency signal passes between the second radio frequency terminal RF2 and the first antenna terminal ANT1, the second arm a2 and the fourth arm a4 are turned on, and the first arm a1 and the third arm A3 are turned off.
When a radio frequency signal passes between the second radio frequency terminal RF2 and the second antenna terminal ANT2, the first arm a1 and the third arm A3 are turned on, and the second arm a2 and the fourth arm a4 are turned off.
When a radio frequency signal passes between the first radio frequency terminal RF1 and the second antenna terminal ANT2, the second arm a2 and the fourth arm a4 are turned on, and the first arm a1 and the third arm A3 are turned off.
Further improved, all capacitance values of the capacitors forming the first arm A1-A4 are the same and are marked as C; the inductance values of the first inductor L1 and the second inductor L2 are the same and are marked as L; the frequency used by the double-pole double-throw radio frequency switch is marked as f; and C and 2L can resonate at f, i.e.
The capacitance C 'of the ninth capacitor C9 and the inductance L' of the third inductor L3 can resonate at f, i.e., the capacitance C 'and the inductance L' are tuned to each other
The working principle of the double-pole double-throw radio frequency switch provided by the invention is explained below.
Fig. 3 shows an equivalent circuit when a radio frequency signal passes between the first radio frequency terminal RF1 and the first antenna terminal ANT1, and the ninth capacitor C9 and the third inductor L3 are omitted for simplicity of analysis. At this time, the first arm a1 and the third arm A3 are turned on, the second arm a2 and the fourth arm a4 are turned off, the first and third switching devices S1 and S3 are turned on to be short-circuited, and the second and fourth switching devices S2 and S4 are turned off to be one capacitor, which is denoted as Coff.
Fig. 4 shows an equivalent circuit further simplified from that shown in fig. 3, assuming that C1-C8 in fig. 3 are all large enough that they can be considered as an alternating current short (AC short) at the operating frequency at which the double pole double throw rf switch is used. In this case, the first arm a1 and the third arm A3 become short-circuited branches, and the second arm a2 and the fourth arm a4 are equivalent to Coff. The first RF terminal RF1 is short-circuited to the first antenna terminal ANT1, the second RF terminal ANT2 is short-circuited to the second RF terminal RF2, the connection between them is equivalent to two coffs in parallel, and an inductor with an equivalent inductance value of L1+ L2, which can generate parallel resonance at the operating frequency used by the double pole double throw RF switch, thereby generating high isolation between RF1/ANT1 and RF2/ANT2 and providing low insertion loss between RF1 and ANT 1.
When radio frequency signals are transmitted between any other two ports, the working principle of the double-pole double-throw radio frequency switch provided by the invention is similar. Compared with the existing double-pole double-throw radio frequency switch, the structure provided by the invention has the advantages that the insertion loss between the conducted ports is low (only through one switching device), and higher isolation degree is generated between the disconnected ports (due to parallel resonance).
The third inductor L3 shown in fig. 2 is used to ensure that the first antenna terminal ANT1 and the second antenna terminal ANT2 have a discharge path to ground at the same time, which plays a very important role in ESD performance of the rf chip product. However, to ensure that the introduction of L3 does not affect the series circuit structure of L1 and L2, a ninth capacitor C9 is introduced at the same time. When the ninth capacitor C9 and the third inductor L3 generate parallel resonance at the operating frequency used by the double-pole double-throw rf switch, the network formed by the ninth capacitor C9 and the third inductor L3 generates a high impedance between the first inductor L1 and the first inductor L2, so that the rf signal is not affected by the introduction of the ninth capacitor C9 and the third inductor L3, thereby ensuring the ESD performance of the first antenna terminal ANT1 and the second antenna terminal ANT2, and maintaining the low insertion loss and high isolation performance of the double-pole double-throw rf switch.
Drawings
The invention will be described in further detail with reference to the following detailed description and accompanying drawings:
fig. 1 is a schematic structural diagram of a conventional double-pole double-throw rf switch.
Fig. 2 is a schematic structural diagram of a first embodiment of the present invention.
Fig. 3 is a simplified circuit diagram of the structure of the first embodiment of the present invention.
Fig. 4 is an equivalent circuit diagram of the structure of the first embodiment of the present invention.
Description of the reference numerals
RF1, RF2 are the first to the second RF terminals
ANT1 and ANT2 represent first to second antenna terminals
A1-A4 are the first to fourth arms
L1-L3 first-third inductors
C1-C9 are the first to ninth capacitors
S1-S4 represent the first to fourth switching devices
Detailed Description
As shown in fig. 2, an embodiment of the double-pole double-throw rf switch of the present invention includes: a first radio frequency end RF1, a second radio frequency end RF2, first to fourth arms A1 to A4, first to third inductors L1 to L3 and first to second antenna ends ANT1 to ANT 2;
the first arm a1 is connected between the first radio frequency terminal RF1 and the first antenna terminal ANT1, the second arm a2 is connected between the first antenna terminal ANT1 and the second radio frequency terminal RF2, the third arm A3 is connected between the second radio frequency terminal RF2 and the second antenna terminal ANT2, the fourth arm a4 is connected between the second antenna terminal ANT2 and the first radio frequency terminal RF1, and the first inductance L1 and the second inductance L2 are connected in series between the first antenna terminal ANT1 and the second antenna terminal ANT 2;
wherein, the first to fourth arms A1-A4 are completely the same in structure, each arm comprises: two capacitors and a switching device, the switching device being connected in series between the two capacitors. When the switching device is turned on, the corresponding arm is turned on; when the switching device is turned off, the corresponding arm is turned off.
The first arm includes: a first capacitor C1, a second capacitor C2 and a first switching device S1, the first switching device S1 being connected in series between the first capacitor C1 and the second capacitor C2.
The second arm includes: a third capacitor C3, a fourth capacitor C4 and a second switching device S2, the second switching device S2 being connected in series between the third capacitor C3 and the fourth capacitor C4.
The third arm includes: a fifth capacitor C5, a sixth capacitor C6 and a third switching device S3, the third switching device S3 being connected in series between the fifth capacitor C5 and the sixth capacitor C6.
The fourth arm includes: a seventh capacitor C7, an eighth capacitor C8, and a fourth switching device S4, the fourth switching device S4 being connected in series between the seventh capacitor C7 and the eighth capacitor C8.
In a further improvement, the inductor further comprises a third inductor L3 and a ninth capacitor C9, one end of the third inductor L3 is connected between the first inductor L1 and the second inductor L2, and the other end is internally grounded; the ninth capacitor C9 is connected in parallel with the third inductor L3.
In a further improvement, the switching devices S1-S4 are PMOS, NMOS, HEMT or LDMOS.
When a radio frequency signal passes between the first radio frequency terminal RF1 and the first antenna terminal ANT1, the first arm a1 and the third arm A3 are turned on, and the second arm a2 and the fourth arm a4 are turned off.
When a radio frequency signal passes between the second radio frequency terminal RF2 and the first antenna terminal ANT1, the second arm a2 and the fourth arm a4 are turned on, and the first arm a1 and the third arm A3 are turned off.
When a radio frequency signal passes between the second radio frequency terminal RF2 and the second antenna terminal ANT2, the first arm a1 and the third arm A3 are turned on, and the second arm a2 and the fourth arm a4 are turned off.
When a radio frequency signal passes between the first radio frequency terminal RF1 and the second antenna terminal ANT2, the second arm a2 and the fourth arm a4 are turned on, and the first arm a1 and the third arm A3 are turned off.
Further improved, all capacitance values of the capacitors forming the first arm A1-A4 are the same and are marked as C; the inductance values of the first inductor L1 and the second inductor L2 are the same and are marked as L; the frequency used by the double-pole double-throw radio frequency switch is marked as f; and C and 2L can resonate at f, i.e.
The capacitance C 'of the ninth capacitor C9 and the inductance L' of the third inductor L3 can resonate at f, i.e., the capacitance C 'and the inductance L' are tuned to each other
The present invention has been described in detail with reference to the specific embodiments and examples, but these are not intended to limit the present invention. Many variations and modifications may be made by one of ordinary skill in the art without departing from the principles of the present invention, which should also be considered as within the scope of the present invention.
Claims (8)
1. A double pole double throw radio frequency switch, comprising: a first radio frequency terminal (RF1), a second radio frequency terminal (RF2), first to fourth arms (A1 to A4), first to third inductors (L1 to L3), and first to second antenna terminals (ANT1, ANT 2);
a first arm (a1) connected between a first radio frequency terminal (RF1) and a first antenna terminal (ANT1), a second arm (a2) connected between the first antenna terminal (ANT1) and a second radio frequency terminal (RF2), a third arm (A3) connected between the second radio frequency terminal (RF2) and a second antenna terminal (ANT2), a fourth arm (a4) connected between the second antenna terminal (ANT2) and a first radio frequency terminal (RF1), a first inductance (L1) and a second inductance (L2) connected in series between the first antenna terminal (ANT1) and the second antenna terminal (ANT 2);
wherein the first to fourth arms (A1-A4) have the same structure, each arm includes: two capacitors and a switching device, the switching device being connected in series between the two capacitors;
the antenna also comprises a third inductor (L3) and a ninth capacitor (C9), wherein one end of the third inductor (L3) is connected between the first inductor (L1) and the second inductor (L2), and the other end of the third inductor is internally grounded to form a discharge path from the first antenna end (ANT1) and the second antenna end (ANT2) to the ground; the ninth capacitor (C9) is connected in parallel with the third inductor (L3).
2. The double-pole double-throw radio frequency switch of claim 1, wherein: the switching devices (S1-S4) are PMOS, NMOS, HEMT or LDMOS.
3. The double-pole double-throw radio frequency switch of claim 1, wherein: when a radio frequency signal passes between the first radio frequency terminal (RF1) and the first antenna terminal (ANT1), the first arm (a1) and the third arm (A3) are turned on, and the second arm (a2) and the fourth arm (a4) are turned off.
4. The double-pole double-throw radio frequency switch of claim 1, wherein: when a radio frequency signal passes between the second radio frequency terminal (RF2) and the first antenna terminal (ANT1), the second arm (a2) and the fourth arm (a4) are turned on, and the first arm (a1) and the third arm (A3) are turned off.
5. The double-pole double-throw radio frequency switch of claim 1, wherein: when a radio frequency signal passes between the second radio frequency terminal (RF2) and the second antenna terminal (ANT2), the first arm (a1) and the third arm (A3) are turned on, and the second arm (a2) and the fourth arm (a4) are turned off.
6. The double-pole double-throw radio frequency switch of claim 1, wherein: when a radio frequency signal passes between the first radio frequency terminal (RF1) and the second antenna terminal (ANT2), the second arm (a2) and the fourth arm (a4) are turned on, and the first arm (a1) and the third arm (A3) are turned off.
7. The double-pole double-throw radio frequency switch of claim 1, wherein: all the capacitance values of the capacitors forming the first to fourth arms (A1-A4) are the same and are marked as C; the inductance values of the first inductor (L1) and the second inductor (L2) are the same and are marked as L; the frequency used by the double-pole double-throw radio frequency switch is marked as f; and C and 2L can resonate at f, i.e.
8. The double-pole double-throw radio frequency switch of claim 1, wherein: the frequency of the double-pole double-throw RF switch is denoted as f, and the capacitance C 'of the ninth capacitor (C9) and the inductance L' of the third inductor (L3) can resonate at f, i.e., the RF switch has a frequency of f
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611149947.4A CN108233912B (en) | 2016-12-13 | 2016-12-13 | Double-pole double-throw radio frequency switch |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611149947.4A CN108233912B (en) | 2016-12-13 | 2016-12-13 | Double-pole double-throw radio frequency switch |
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| CN108233912A CN108233912A (en) | 2018-06-29 |
| CN108233912B true CN108233912B (en) | 2021-07-06 |
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| CN201611149947.4A Active CN108233912B (en) | 2016-12-13 | 2016-12-13 | Double-pole double-throw radio frequency switch |
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| CN111181539B (en) * | 2020-01-16 | 2023-08-11 | 上海闻泰电子科技有限公司 | Double-pole double-throw radio frequency switch, production test method thereof and mobile communication terminal |
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| CN101098135A (en) * | 2006-06-29 | 2008-01-02 | 株式会社瑞萨科技 | Semiconductor integrated circuit device and RF moudle |
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| CN106612106A (en) * | 2015-10-27 | 2017-05-03 | 湖南格兰德芯微电子有限公司 | Composite transistor radio frequency power amplifier |
| CN107005264A (en) * | 2015-12-31 | 2017-08-01 | 华为技术有限公司 | The antenna switching control method of wireless terminal and wireless terminal |
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| US7254371B2 (en) * | 2004-08-16 | 2007-08-07 | Micro-Mobio, Inc. | Multi-port multi-band RF switch |
| WO2009095815A2 (en) * | 2008-01-31 | 2009-08-06 | Nxp B.V. | Antenna interface circuit and method for transmitting and receiving signals in collocated wireless communication systems |
| US20090253384A1 (en) * | 2008-04-04 | 2009-10-08 | Stmicroelectronics, Ltd. | Dual Mode Radio Frequency Front End Circuit |
| CN201577079U (en) * | 2010-01-19 | 2010-09-08 | 惠州市恒睿电子科技有限公司 | Two terminal full solid-state switch using wireless radio frequency identification technology |
| CN101958704B (en) * | 2010-09-25 | 2012-07-04 | 陈清尧 | Four-path remote control switch controller |
| CN202513882U (en) * | 2012-02-21 | 2012-10-31 | 京信通信系统（中国）有限公司 | Multi-carrier power amplifier |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101098135A (en) * | 2006-06-29 | 2008-01-02 | 株式会社瑞萨科技 | Semiconductor integrated circuit device and RF moudle |
| CN104659469A (en) * | 2015-02-28 | 2015-05-27 | 深圳市中兴移动通信有限公司 | Antenna assembly and control method thereof |
| CN205017288U (en) * | 2015-08-07 | 2016-02-03 | 康希通信科技（上海）有限公司 | Single pole single throw RF switch and RF switch is thrown to single -pole double throw RF switch and hilted broadsword that constitute more thereof |
| CN106612106A (en) * | 2015-10-27 | 2017-05-03 | 湖南格兰德芯微电子有限公司 | Composite transistor radio frequency power amplifier |
| CN107005264A (en) * | 2015-12-31 | 2017-08-01 | 华为技术有限公司 | The antenna switching control method of wireless terminal and wireless terminal |
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