CN117713024A - Protective circuit - Google Patents
Protective circuit Download PDFInfo
- Publication number
- CN117713024A CN117713024A CN202410170593.XA CN202410170593A CN117713024A CN 117713024 A CN117713024 A CN 117713024A CN 202410170593 A CN202410170593 A CN 202410170593A CN 117713024 A CN117713024 A CN 117713024A
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- Prior art keywords
- circuit
- protection
- diode
- parallel resonant
- resonant circuit
- 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.)
- Pending
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- 230000001681 protective effect Effects 0.000 title description 2
- 239000003990 capacitor Substances 0.000 claims description 19
- 230000000712 assembly Effects 0.000 claims 2
- 238000000429 assembly Methods 0.000 claims 2
- 230000003071 parasitic effect Effects 0.000 description 3
- 230000001052 transient effect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
- H02H9/045—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage adapted to a particular application and not provided for elsewhere
- H02H9/046—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage adapted to a particular application and not provided for elsewhere responsive to excess voltage appearing at terminals of integrated circuits
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- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention provides a protection circuit, which comprises: a first shield system including a first shield assembly; the first protection component comprises a first diode and a second diode; the first end of the first parallel resonance circuit is connected to the cathode of the first diode and the anode of the second diode respectively, and the second end of the first parallel resonance circuit is connected to the signal input end of the protected circuit; a second protection system comprising a second protection component comprising a third diode and a fourth diode; and the first end of the second parallel resonant circuit is connected to the cathode of the third diode and the anode of the fourth diode respectively, and the second end of the second parallel resonant circuit is connected to the signal input end of the protected circuit. The protection circuit can reduce the influence of the protection circuit on the radio frequency performance of the protected circuit.
Description
Technical Field
The invention relates to the technical field of wireless communication, in particular to a protection circuit.
Background
The ESD (electrostatic discharge) protection technology in the related art is mainly implemented by using electronic components such as a common diode, a resistor, a capacitor, a TVS (transient suppression diode), an SCR (silicon controlled rectifier), a BJT (bipolar junction transistor), a MOS (field effect transistor), and the like.
The ESD protection circuit composed of the above components is usually connected in parallel to the input terminal of the protected circuit, so as to introduce the transient current generated by the electrostatic discharge into the ground through the components, thereby protecting the electronic equipment using the protected circuit from damage.
However, the ESD protection circuit not only introduces a larger parasitic capacitance at the input end of the protected circuit, but also generates corresponding noise and nonlinearity due to the matching of the input of the pull-bias chip, and further damages the radio frequency performance of the protected circuit.
Therefore, a new protection circuit is needed to solve the above problems.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a protection circuit to solve the problem that the ESD protection circuit in the related art can affect the radio frequency performance of the protected circuit.
In order to solve the technical problems, the invention adopts the following technical scheme:
the invention provides a protection circuit, which is used for carrying out electrostatic discharge protection on a protected circuit, and comprises the following components:
a first shield system including a first shield assembly; the first protection component comprises a first diode and a second diode; the positive electrode of the first diode is connected to the working voltage, and the negative electrode of the second diode is connected to the working voltage;
a first parallel resonant circuit, wherein a first end of the first parallel resonant circuit is connected to the cathode of the first diode and the anode of the second diode respectively, and a second end of the first parallel resonant circuit is connected to the signal input end of the protected circuit;
a second guard system comprising a second guard assembly comprising a third diode and a fourth diode; the positive electrode of the third diode is grounded, and the negative electrode of the fourth diode is grounded; the second protection system and the first protection system are respectively used for carrying out electrostatic discharge protection on the protected circuit;
a second parallel resonant circuit, a first end of which is connected to the negative electrode of the third diode and the positive electrode of the fourth diode, respectively, and a second end of which is connected to the signal input end of the protected circuit; the second parallel resonant circuit and the first parallel resonant circuit are respectively used for resonating the radio frequency signal input to the protected circuit.
Preferably, the first protection system comprises a plurality of first protection components, and the plurality of first protection components are mutually connected in parallel.
Preferably, said first protection system comprises two of said first protection components.
Preferably, the first parallel resonant circuit includes a first capacitor and a first inductor; the first end of the first capacitor is connected with the first end of the first inductor and is used as the first end of the first parallel resonant circuit together; the second end of the first capacitor is connected with the second end of the first inductor and is used as the second end of the first parallel resonance circuit together.
Preferably, the second protection system comprises a plurality of second protection components, and the plurality of second protection components are mutually connected in parallel.
Preferably, said second protection system comprises two of said second protection components.
Preferably, the second parallel resonant circuit includes a second capacitor and a second inductor; the first end of the second capacitor is connected with the first end of the second inductor and is used as the first end of the second parallel resonant circuit together; the second end of the second capacitor is connected with the second end of the second inductor and is used as the second end of the second parallel resonant circuit together.
Preferably, the first parallel resonant circuit includes a first electrostatic discharge device and a third inductance; the first end of the first electrostatic discharge device and the first end of the third inductor are used as the first end of the first parallel resonant circuit together; the second end of the first electrostatic discharge device and the second end of the third inductor are used as the second end of the first parallel resonance circuit together.
Preferably, the second parallel resonant circuit includes a second electrostatic discharge device and a fourth inductance; the first end of the second electrostatic discharge device and the first end of the fourth inductor are used as the first end of the second parallel resonant circuit together; the second end of the second electrostatic discharge device and the second end of the fourth inductor are used as the second end of the second parallel resonant circuit together.
Compared with the related art, the protection circuit combines the first parallel resonant circuit and the second parallel resonant circuit with the first protection system and the second protection system respectively, so that the first parallel resonant circuit and the second parallel resonant circuit can work at required frequencies by adjusting proper resonant frequencies, and parasitic capacitance and nonlinearity introduced by the first protection system and the second protection system are effectively blocked by utilizing high impedance generated when the first parallel resonant circuit and the second parallel resonant circuit resonate, thereby reducing the influence of the protection circuit on the radio frequency performance of the protected circuit and improving the signal quality.
Drawings
The present invention will be described in detail with reference to the accompanying drawings. The foregoing and other aspects of the invention will become more apparent and more readily appreciated from the following detailed description taken in conjunction with the accompanying drawings. In the accompanying drawings:
fig. 1 is a block diagram of an overall circuit of a protection circuit according to an embodiment of the present invention.
Detailed Description
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the applications herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description and claims of the present application and in the description of the figures above are intended to cover non-exclusive inclusions. The terms first, second and the like in the description and in the claims or in the above-described figures, are used for distinguishing between different objects and not necessarily for describing a sequential or chronological order.
Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.
The following description of the embodiments of the present invention 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 invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
An embodiment of the present invention provides a protection circuit 100, as shown in fig. 1, which includes: a first protection system 1, a first parallel resonant circuit 2, a second protection system 3 and a second parallel resonant circuit 4.
The protection CIRCUIT 100 (electrostatic discharge protection CIRCUIT or ESD protection CIRCUIT) is used for performing electrostatic discharge protection on the protected CIRCUIT 5 (COTE ciruict); the signal INPUT terminal INPUT of the protected circuit 5 is connected to the output terminal of the external circuit, the power supply terminal of the protected circuit 5 is connected to the operating voltage VDD, and the load terminal of the protected circuit 5 is grounded.
The first protection system 1 comprises a first protection component; the first protection component comprises a first diode and a second diode; the positive pole of the first diode is connected to the working voltage VDD, and the negative pole of the second diode is connected to the working voltage VDD.
The first end of the first parallel resonant circuit 2 is connected to the cathode of the first diode and the anode of the second diode, respectively, and the second end of the first parallel resonant circuit 2 is connected to the signal INPUT terminal INPUT of the protected circuit 5.
The second protection system 3 comprises a second protection assembly comprising a third diode and a fourth diode; the positive electrode of the third diode is grounded, and the negative electrode of the fourth diode is grounded; the second protection system 3 and the first protection system 1 are respectively used for performing electrostatic discharge protection on the protected circuit 5. Specifically, the first protection system 1 achieves electrostatic discharge protection of the operating voltage VDD to the protected circuit 5, and the second protection system 3 achieves electrostatic discharge protection of the protected circuit 5 to ground.
The first end of the second parallel resonant circuit 4 is connected to the cathode of the third diode and the anode of the fourth diode, respectively, and the second end of the second parallel resonant circuit 4 is connected to the signal INPUT end INPUT of the protected circuit 5; the second parallel resonant circuit 4 and the first parallel resonant circuit 2 are respectively configured to resonate a radio frequency signal inputted to the protected circuit 5.
Specifically, the first protection system 1 includes a plurality of first protection components, and a plurality of the first protection components are connected in parallel, and of course, according to actual requirements, the first protection system 1 may also be designed to include one first protection component; the second protection system 3 comprises a plurality of second protection components, and a plurality of the second protection components are mutually connected in parallel, and of course, the second protection system 3 can also be designed to comprise one second protection component according to actual requirements.
In this embodiment, the first protection system 1 includes two first protection components, namely a first sub-protection component 11 and a second sub-protection component 12, which have the same circuit structure. Wherein the first sub-protection component 11 comprises a first diode D1 and a second diode D2, and the second protection component 12 comprises a first diode D3 and a second diode D4.
The positive electrode of the first diode D1 in the first sub-protection component 11 and the positive electrode of the first diode D3 in the second protection component 12 are respectively connected to the working voltage VDD, and the negative electrode of the second diode D2 in the first sub-protection component 11 and the negative electrode of the second diode D4 in the second protection component 12 are respectively connected to the working voltage VDD; correspondingly, the first end of the first parallel resonant circuit 2 is connected to the cathode of the first diode D1 and the anode of the second diode D2 in the first sub protection assembly 11, and the cathode of the first diode D3 and the anode of the second diode D4 in the second protection assembly 12, respectively.
In this embodiment, the first parallel resonant circuit 2 includes a first capacitor C1 and a first inductor L1; the first end of the first capacitor C1 and the first end of the first inductor L1 are used together as the first end of the first parallel resonance circuit 2; the second terminal of the first capacitor C1 and the second terminal of the first inductor L1 together serve as the second terminal of the first parallel resonant circuit 2.
In this embodiment, the second protection system 3 includes two second protection components, namely a third sub-protection component 31 and a fourth sub-protection component 32, which have the same circuit structure. Wherein the third sub-protection component 31 comprises a third diode D5 and a fourth diode D6, and the fourth sub-protection component 32 comprises a first third diode D7 and a fourth diode D8;
the positive electrode of the third diode D5 in the third sub-protection component 31 and the positive electrode of the fourth diode D7 in the fourth sub-protection component 32 are respectively grounded, and the negative electrode of the third diode D6 in the third sub-protection component 31 and the negative electrode of the fourth diode D8 in the fourth sub-protection component 32 are grounded; correspondingly, the first end of the second parallel resonant circuit 4 is connected to the cathode of the third diode D5 and the anode of the fourth diode D6 in the third sub-protection assembly 31, and the cathode of the third diode D7 and the anode of the fourth diode D8 in the fourth sub-protection assembly 32, respectively.
In the present embodiment, the second parallel resonant circuit 4 includes a second capacitor C2 and a second inductance L2; the first end of the second capacitor C2 and the first end of the second inductor L2 are used together as the first end of the second parallel resonant circuit 4; the second end of the second capacitor C2 and the second end of the second inductance L2 together serve as the second end of the second parallel resonant circuit 4.
The protection circuit 100 of the present embodiment combines the first parallel resonant circuit 2 and the second parallel resonant circuit 4 with the first protection system 1 and the second protection system 3 respectively, so that the first parallel resonant circuit 2 and the second parallel resonant circuit 4 can work at a required frequency (specific frequency) by adjusting the capacitance value of the first capacitor C1 and the second capacitor C2 and the inductance value of the first inductor L1 and the second inductor L2, and when the signal frequency of the protected circuit 5 matches the resonance frequency of the first parallel resonant circuit 2 and the second parallel resonant circuit 4, the parasitic capacitance and the nonlinearity introduced by the first protection system 1 and the second protection system 3 are effectively blocked or weakened by utilizing the high impedance generated when the signal frequency of the protected circuit 5 matches the resonance frequency of the first parallel resonant circuit 2 and the second parallel resonant circuit 4, so that the influence of the protection circuit 100 on the radio frequency performance of the protected circuit 5 is reduced, thereby improving the signal quality and providing good electrostatic discharge protection. In addition, when the low-frequency electrostatic discharge occurs, the first parallel resonant circuit 2 and the second parallel resonant circuit 4 operate in a low-impedance state, and effective discharge of the transient current can be realized.
Example two
The embodiment of the present invention provides a protection circuit, which has substantially the same circuit structure as the protection circuit 100 in the first embodiment, and is different from the first parallel resonant circuit 2 and the second parallel resonant circuit 4 of the protection circuit 100 in the first embodiment.
The first parallel resonant circuit in this embodiment includes a first electrostatic discharge device and a third inductance; the first end of the first electrostatic discharge device and the first end of the third inductor are used as the first end of the first parallel resonant circuit together; the second end of the first electrostatic discharge device and the second end of the third inductor are used as the second end of the first parallel resonance circuit together.
The second parallel resonant circuit in this embodiment includes a second electrostatic discharge device and a fourth inductance; the first end of the second electrostatic discharge device and the first end of the fourth inductor are used as the first end of the second parallel resonant circuit together; the second end of the second electrostatic discharge device and the second end of the fourth inductor are used as the second end of the second parallel resonance circuit together.
Since the protection circuit in the present embodiment is substantially the same as the protection circuit 100 in the first embodiment, the technical effects achieved by the protection circuit 100 in the first embodiment can be achieved, and the description thereof is omitted herein; in addition, the protection circuit in the present embodiment can further improve the esd protection effect by designing the first parallel resonant circuit and the second parallel resonant circuit different from the protection circuit in the first embodiment.
It should be noted that the above embodiments described above with reference to the drawings are only for illustrating the present invention and not for limiting the scope of the present invention, and it should be understood by those skilled in the art that modifications or equivalent substitutions to the present invention are intended to be included in the scope of the present invention without departing from the spirit and scope of the present invention. Furthermore, unless the context indicates otherwise, words occurring in the singular form include the plural form and vice versa. In addition, unless specifically stated, all or a portion of any embodiment may be used in combination with all or a portion of any other embodiment.
Claims (9)
1. A protection circuit for performing electrostatic discharge protection on a protected circuit, the protection circuit comprising:
a first shield system including a first shield assembly; the first protection component comprises a first diode and a second diode; the positive electrode of the first diode is connected to the working voltage, and the negative electrode of the second diode is connected to the working voltage;
a first parallel resonant circuit, wherein a first end of the first parallel resonant circuit is connected to the cathode of the first diode and the anode of the second diode respectively, and a second end of the first parallel resonant circuit is connected to the signal input end of the protected circuit;
a second guard system comprising a second guard assembly comprising a third diode and a fourth diode; the positive electrode of the third diode is grounded, and the negative electrode of the fourth diode is grounded; the second protection system and the first protection system are respectively used for carrying out electrostatic discharge protection on the protected circuit;
a second parallel resonant circuit, a first end of which is connected to the negative electrode of the third diode and the positive electrode of the fourth diode, respectively, and a second end of which is connected to the signal input end of the protected circuit; the second parallel resonant circuit and the first parallel resonant circuit are respectively used for resonating the radio frequency signal input to the protected circuit.
2. The protection circuit of claim 1, wherein the first protection system comprises a plurality of the first protection components, the plurality of the first protection components being connected in parallel with one another.
3. The guard circuit of claim 2, wherein the first guard system comprises two of the first guard assemblies.
4. The protection circuit of claim 1, wherein the first parallel resonant circuit comprises a first capacitance and a first inductance; the first end of the first capacitor is connected with the first end of the first inductor and is used as the first end of the first parallel resonant circuit together; the second end of the first capacitor is connected with the second end of the first inductor and is used as the second end of the first parallel resonance circuit together.
5. The protection circuit of claim 1, wherein the second protection system comprises a plurality of the second protection components, the plurality of the second protection components being connected in parallel with one another.
6. The guard circuit of claim 5 wherein the second guard system comprises two of the second guard assemblies.
7. The protection circuit of claim 1, wherein the second parallel resonant circuit comprises a second capacitance and a second inductance; the first end of the second capacitor is connected with the first end of the second inductor and is used as the first end of the second parallel resonant circuit together; the second end of the second capacitor is connected with the second end of the second inductor and is used as the second end of the second parallel resonant circuit together.
8. The protection circuit of claim 1, wherein the first parallel resonant circuit comprises a first electrostatic discharge device and a third inductance; the first end of the first electrostatic discharge device and the first end of the third inductor are used as the first end of the first parallel resonant circuit together; the second end of the first electrostatic discharge device and the second end of the third inductor are used as the second end of the first parallel resonance circuit together.
9. The protection circuit of claim 1, wherein the second parallel resonant circuit comprises a second electrostatic discharge device and a fourth inductance; the first end of the second electrostatic discharge device and the first end of the fourth inductor are used as the first end of the second parallel resonant circuit together; the second end of the second electrostatic discharge device and the second end of the fourth inductor are used as the second end of the second parallel resonant circuit together.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410170593.XA CN117713024A (en) | 2024-02-06 | 2024-02-06 | Protective circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410170593.XA CN117713024A (en) | 2024-02-06 | 2024-02-06 | Protective circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117713024A true CN117713024A (en) | 2024-03-15 |
Family
ID=90155690
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410170593.XA Pending CN117713024A (en) | 2024-02-06 | 2024-02-06 | Protective circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117713024A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005102139A (en) * | 2003-08-26 | 2005-04-14 | Yazaki Corp | High frequency switching circuit, on-vehicle communication system using the same, and band width adjustment method for the same |
| CN1662113A (en) * | 2004-02-27 | 2005-08-31 | 联华电子股份有限公司 | Protective circuit of electrostatic discharge suitable to integrated circuit in radio frequency |
| US20090195946A1 (en) * | 2008-02-05 | 2009-08-06 | Zerog Wireless, Inc. | Electrostatic Discharge Protection Using an Intrinsic Inductive Shunt |
| WO2011021411A1 (en) * | 2009-08-21 | 2011-02-24 | 株式会社村田製作所 | Esd protection device |
| CN103795053A (en) * | 2014-02-25 | 2014-05-14 | 中国人民解放军理工大学 | Novel lightning protection device for antenna port |
| CN106329037A (en) * | 2015-06-30 | 2017-01-11 | 展讯通信（上海）有限公司 | Passive signal separation integrated circuit |
-
2024
- 2024-02-06 CN CN202410170593.XA patent/CN117713024A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005102139A (en) * | 2003-08-26 | 2005-04-14 | Yazaki Corp | High frequency switching circuit, on-vehicle communication system using the same, and band width adjustment method for the same |
| CN1662113A (en) * | 2004-02-27 | 2005-08-31 | 联华电子股份有限公司 | Protective circuit of electrostatic discharge suitable to integrated circuit in radio frequency |
| US20090195946A1 (en) * | 2008-02-05 | 2009-08-06 | Zerog Wireless, Inc. | Electrostatic Discharge Protection Using an Intrinsic Inductive Shunt |
| WO2011021411A1 (en) * | 2009-08-21 | 2011-02-24 | 株式会社村田製作所 | Esd protection device |
| CN103795053A (en) * | 2014-02-25 | 2014-05-14 | 中国人民解放军理工大学 | Novel lightning protection device for antenna port |
| CN106329037A (en) * | 2015-06-30 | 2017-01-11 | 展讯通信（上海）有限公司 | Passive signal separation integrated circuit |
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