CN1581627A - Protective circuit - Google Patents
Protective circuit Download PDFInfo
- Publication number
- CN1581627A CN1581627A CN 03144086 CN03144086A CN1581627A CN 1581627 A CN1581627 A CN 1581627A CN 03144086 CN03144086 CN 03144086 CN 03144086 A CN03144086 A CN 03144086A CN 1581627 A CN1581627 A CN 1581627A
- Authority
- CN
- China
- Prior art keywords
- protective circuit
- circuit
- gas discharge
- silicon
- diode
- 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
Links
Images
Abstract
The protection circuit includes gas discharge tube and silicon protective circuit connected between two signal lines in parallel, and decoupler connected to signal line between gas discharge tube and silicon protective circuit. The said silicon protective circuit includes silicon protective diode and bridge circuit composed of diodes. Silicon protective diode is connected to two balanced connection points in bridge circuit. Other two balanced connection points of bridge circuit are connected to signal lines.
Description
Technical field
The present invention relates to the guard technology of communication equipment, particularly a kind of protective circuit.
Background technology
The signaling interface of using always on the communication equipment, as RS422, RS485, E1/T1 etc., transmission range is more than hundreds of rice, the cable of these interfaces is probably by the indoor open air that extends in actual use, as thunderstorm hour, electromagnetic pulse can be responded to bigger temporary overvoltage in these signal lines and loop thereof, easily signaling interface is damaged.Therefore, for the safe and reliable operation of maintain communications equipment, must take the overvoltage protection measure to the signal port circuit.
At present, the technical scheme of overvoltage protection adopts one-level gas discharge tube, one-level silicon protective circuit or gas discharge tube and silicon protective circuit that signaling interface is carried out differential mode, common mode protection.
Adopt one-level gas discharge tube protective circuit, its shortcoming is that the discharge tube response time is slow, and when action, the residual voltage ratio of generation is higher, and is unfavorable to the protection of back sensitive circuit.Adopt one-level silicon protective circuit, shortcoming is that tolerance lightning impulse discharge capacity is not enough.If adopt the big silicon protective circuit of discharge capacity, its junction capacitance will be very big, influences signal transfer quality in the circuit, and the transmission rate of signal does not just reach the maximum requirement of 20Mbit/s.If add the one-level gas discharge tube before increasing the silicon protective circuit in front, because back level silicon protective circuit through-current capacity is little, the resistance that cooperates between the two poles of the earth will be selected bigger value for use, will increase the decay of signal like this, influence the transmission range of signal.
Summary of the invention
The invention provides a kind of protective circuit, to solve in the prior art problem that can not protect signaling interface very effectively when the transient state differential mode that causes by lightning induction and common mode overvoltage, the overcurrent.
For addressing the above problem, technical scheme of the present invention is as follows:
A kind of protective circuit; comprise and be connected two gas discharge tube and silicon protective circuits between the parallel signal line; and be connected in gas and put the decoupling device on the holding wire between pipe and silicon protective circuit; wherein; described silicon protective circuit comprises silicon protection diode and the bridge circuit that is constituted by a diode; silicon protection diode is connected between the bridge circuit two balance tie points, and the two balance tie points in addition of bridge circuit are connected with holding wire.
When described silicon protective circuit is N, then form the protection of N level.
Described gas discharge tube can be two utmost point gas discharge tubes or three utmost point gas discharge tubes, is used to suppress the differential mode overvoltage.
Described two utmost point gas discharge tubes are one, and it is connected between two parallel signal lines.
Described two utmost point gas discharge tubes are a plurality of, and these a plurality of two utmost point gas discharge tubes are connected in parallel between two parallel signal lines and between holding wire and the ground.
Two balance tie points of described silicon protection diode and bridge circuit are respectively by diode ground connection.
The tie point that described bridge circuit is connected with holding wire is by silicon protection diode ground connection.
Described decoupling device is a resistance, perhaps inductance, and perhaps resistance is connected with inductance.
Because the present invention has adopted bridge circuit; can reduce the silicon protection diode capacitance value that is connected across the holding wire two ends largely; thereby under the prerequisite that does not influence signal transmission quality; make with signaling interface and can bear the impulse current that causes because of thunder and lightning up to 3KA (8/20us waveform); strengthen the ability of the anti-thunderbolt of signaling interface greatly, reduced the thunderbolt spoilage of the signaling interface of product.
Description of drawings
Fig. 1 is the schematic diagram of lightning protection circuit of the present invention;
Fig. 2 removes the lightning protection circuit principle of common mode protection for the present invention;
Fig. 3 is used for the lightning protection circuit schematic diagram of coaxial line for the present invention.
Fig. 4 increases the lightning protection circuit schematic diagram of back level decoupling resistance for the present invention.
Embodiment
Consult shown in Figure 1, lightning protection circuit by be connected holding wire to discharge tube G, silicon protective circuit and decoupling resistance R1 and the R2 that is connected on the holding wire form, this discharge tube G is three utmost point gas discharge tubes.The silicon protective circuit comprises silicon protection diode VD and the bridge circuit of being made up of fast recovery diode D1, D2, D3, D4, D5, D6.Silicon protection diode is connected between the bridge circuit two balance tie points, and the two balance tie points in addition of bridge circuit are connected with holding wire.Gas discharge tube G and silicon protective circuit constitute the differential mode and the common mode protective circuit of a two-stage.
The gas discharge tube G of the first order is used for the bypass big electric current of transient state of releasing, and can suppress the common mode overvoltage, can suppress the differential mode overvoltage again.Partial silicon protection diode VD is used for the clamp pressure limiting, by cooperating with fast recovery diode D1, D2, D3, D4, D5, D6, suppresses remaining differential mode and common mode overvoltage that gas discharge tube G action back produces, the device of protection back.For second level protective circuit, the path that difference is touched protection is D2 → VD → D3 and D4 → VD → D1, and the path of common mode protection is D2 → VD → D5 and D6 → VD → D1 and D4 → VD → D5 and D6 → VD → D3.
The first order often is called thick protection, and the second level often is called thin protection.Resistance R 1 between these the two poles of the earth, R2 work to improve the operating characteristics of gas discharge tube G and promote the two-stage protective feature to cooperate.After the temporary overvoltage ripple arrived protection circuit along the signal line transmission, because gas discharge tube G has higher discharge voltage and long response time, it can not very fast discharge conducting.Before gas discharge tube G does not discharge as yet; silicon protection diode VD will at first puncture; and flow through transient current; increase along with this branch road transient current; pressure drop on resistance R 1, the R2 also correspondingly increases; this pressure drop is added on gas discharge tube G two ends, just impels gas discharge tube G to move discharge as early as possible.After gas discharge tube G discharge, the passage that it will provide a bypass to release the big electric current of transient state, it also can play over-voltage simultaneously, and implements the protection to back resistance R 1, R2, silicon protection diode VD and fast recovery diode.
Than higher signaling interface,, need the silicon protection diode that adopts through-current capacity bigger for transmission rate (reaching 20Mbit/s) in order to guarantee lightning protection effect.And the bigger silicon of existing through-current capacity protects diode junction capacitance also relatively big, and being used on the circuit to influence signal transfer quality.Therefore the bridge circuit that adopts diode D1, D2, D3, D4 to form can reduce the silicon protection diode capacitance value that is connected across the holding wire two ends largely, thereby reach the purpose that does not influence signal transmission quality.When the impedance of diode D2 and D3, D1 and D4 equated, when promptly the opposite end of bridge reached balance, the impedance phase of silicon protection diode VD was zero to the two ends of holding wire, and the influence of its electric capacity can be ignored.At this moment the electric capacity between line is the capacitances in series of electric capacity and the diode D3 of diode D2, and the capacitances in series of the electric capacity of diode D1 and diode D4, and the forward electric capacity of fast recovery diode D1, D2, D3, D4 is all little, therefore this moment, line capacitance was smaller, can satisfy the requirement of high speed transmission of signals quality fully.
Consult shown in Figure 2ly, change the gas discharge tube G among Fig. 1 into the secondary gas discharge tube, prime only differs from touches protection, and perhaps diode removes D5, D6, and a back level protective circuit is only carried out the differential mode protection.
Also three utmost point gas discharge tube G among Fig. 1 can be changed into the two poles of the earth gas discharge tube that adopts varying number and realize the protection of differential mode, common mode, change resistance R into inductance or resistance and inductance series system.
Adopt the coaxial cable transmission for signaling interface, protective circuit can be changed to shown in Figure 3.The effect of two utmost point gas discharge tube G of ground connection mainly is the lightning overvoltage of screen induction of releasing, and the back level connects a silicon protection diode over the ground, can further reduce the residual voltage of back level.
Also the back level among Fig. 1 can be increased decoupling resistance R3, R4, protective circuit can be changed to shown in Figure 4, can better carry out the lightning protection energy with the protected circuit part of back like this and cooperate.
For the present invention, the silicon among Fig. 1 protection diode VD and fast recovery diode D1, D2, D3, D4, D5, D6 can be integrated in the integrated circuit, but its reduce electric capacity and restriction differential mode, the superpotential method of common mode is same as described above.
Lightning protection circuit of the present invention can not design in equipment, but is designed to the effect that an external lightning protection device reaches the guard signal interface.
Claims (10)
1, a kind of protective circuit comprises being connected two gas discharge tube and silicon protective circuits between the parallel signal line, and is connected in gas and puts the decoupling device on the holding wire between pipe and silicon protective circuit; It is characterized in that described silicon protective circuit comprises silicon protection diode and the bridge circuit that is constituted by a diode, silicon protection diode is connected between the bridge circuit two balance tie points, and the two balance tie points in addition of bridge circuit are connected with holding wire.
2, protective circuit as claimed in claim 1 is characterized in that, when described silicon protective circuit is N, then forms the protection of N level.
3, protective circuit as claimed in claim 1 is characterized in that, described gas discharge tube can be two utmost point gas discharge tubes or three utmost point gas discharge tubes, is used to suppress the differential mode overvoltage.
4, protective circuit as claimed in claim 3 is characterized in that, described two utmost point gas discharge tubes are one, and it is connected between two parallel signal lines.
5, protective circuit as claimed in claim 3 is characterized in that, described two utmost point gas discharge tubes are a plurality of, and these a plurality of two utmost point gas discharge tubes are connected in parallel between two parallel signal lines and between holding wire and the ground.
As the arbitrary described protective circuit of claim 1 to 6, it is characterized in that 6, two balance tie points of described silicon protection diode and bridge circuit are respectively by diode ground connection.
As the arbitrary described high speed signal mouth lightning protection circuit of claim 1 to 6, it is characterized in that 7, the tie point that described bridge circuit is connected with holding wire is by silicon protection diode ground connection.
8, protective circuit as claimed in claim 1 is characterized in that, described decoupling device is a resistance, perhaps inductance, and perhaps resistance is connected with inductance.
9, protective circuit as claimed in claim 1 is characterized in that, described silicon protection diode and bridge circuit are integrated in the integrated circuit.
10, protective circuit as claimed in claim 1 is characterized in that, the back level of described silicon protective circuit also is connected with back level decoupling device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03144086 CN1581627A (en) | 2003-07-31 | 2003-07-31 | Protective circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03144086 CN1581627A (en) | 2003-07-31 | 2003-07-31 | Protective circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1581627A true CN1581627A (en) | 2005-02-16 |
Family
ID=34579585
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 03144086 Pending CN1581627A (en) | 2003-07-31 | 2003-07-31 | Protective circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1581627A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101764399A (en) * | 2009-12-21 | 2010-06-30 | 浙江恒丰光电技术有限公司 | Cable television signal lightning arrester |
| CN102623530A (en) * | 2011-01-26 | 2012-08-01 | 常熟市福莱德连接器科技有限公司 | Antistatic photovoltaic connector |
| CN102684181A (en) * | 2012-05-14 | 2012-09-19 | 江苏中科梦兰电子科技有限公司 | Anti-static and lightning-prevention dual protection circuit |
| WO2016034121A1 (en) * | 2014-09-03 | 2016-03-10 | 烽火通信科技股份有限公司 | Lightning protection circuit and method for direct-current power supply port of communication device |
| CN108110743A (en) * | 2017-12-20 | 2018-06-01 | 中国航空工业集团公司洛阳电光设备研究所 | A kind of high speed signal indirect stroke electric transient susceptibility protective device and design method |
| CN110138189A (en) * | 2018-02-02 | 2019-08-16 | 安雷科技股份有限公司 | For the protection circuit of Ethernet and with the power supply end equipment for protecting circuit |
| CN111211550A (en) * | 2020-01-13 | 2020-05-29 | 杭州迪普科技股份有限公司 | Protection circuit |
| CN112910484A (en) * | 2021-01-21 | 2021-06-04 | 睿高(广州)通信技术有限公司 | Lightning protection system for communication port of airborne power amplifier equipment |
-
2003
- 2003-07-31 CN CN 03144086 patent/CN1581627A/en active Pending
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101764399A (en) * | 2009-12-21 | 2010-06-30 | 浙江恒丰光电技术有限公司 | Cable television signal lightning arrester |
| CN102623530A (en) * | 2011-01-26 | 2012-08-01 | 常熟市福莱德连接器科技有限公司 | Antistatic photovoltaic connector |
| CN102684181A (en) * | 2012-05-14 | 2012-09-19 | 江苏中科梦兰电子科技有限公司 | Anti-static and lightning-prevention dual protection circuit |
| WO2016034121A1 (en) * | 2014-09-03 | 2016-03-10 | 烽火通信科技股份有限公司 | Lightning protection circuit and method for direct-current power supply port of communication device |
| CN108110743A (en) * | 2017-12-20 | 2018-06-01 | 中国航空工业集团公司洛阳电光设备研究所 | A kind of high speed signal indirect stroke electric transient susceptibility protective device and design method |
| CN108110743B (en) * | 2017-12-20 | 2019-04-16 | 中国航空工业集团公司洛阳电光设备研究所 | A kind of high speed signal indirect stroke electric transient susceptibility protective device and design method |
| CN110138189A (en) * | 2018-02-02 | 2019-08-16 | 安雷科技股份有限公司 | For the protection circuit of Ethernet and with the power supply end equipment for protecting circuit |
| CN110138189B (en) * | 2018-02-02 | 2021-09-03 | 安雷科技股份有限公司 | Protection circuit for Ethernet and power supply end equipment with protection circuit |
| CN111211550A (en) * | 2020-01-13 | 2020-05-29 | 杭州迪普科技股份有限公司 | Protection circuit |
| CN112910484A (en) * | 2021-01-21 | 2021-06-04 | 睿高(广州)通信技术有限公司 | Lightning protection system for communication port of airborne power amplifier equipment |
| CN112910484B (en) * | 2021-01-21 | 2023-02-28 | 睿高(广州)通信技术有限公司 | Lightning protection system for communication port of airborne power amplifier equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102185698B (en) | Ethernet power supply port protective circuit and ethernet power supply equipment | |
| CN101227087B (en) | PoE port and lightning protection device thereof | |
| CN100470992C (en) | Thunder proof protective circuit for Ethernet interface | |
| CN200950537Y (en) | Protective circuit | |
| CN1581627A (en) | Protective circuit | |
| CN202749808U (en) | Signal lightning protection circuit | |
| CN214174440U (en) | Lightning protection ultrasonic wave anemorumbometer | |
| CN103414177A (en) | Electromagnetic protection circuit of analog signal input line | |
| CN203481808U (en) | Lightning protection circuit protecting RS232 communication signal | |
| CN203261026U (en) | Mbps network surge protection device with POE function | |
| CN202856345U (en) | Direct current lightning prevention electrostatic prevention protection circuit | |
| CN203933004U (en) | A kind of without leakage current the large discharge capacity surge protector without afterflow | |
| CN2596644Y (en) | IGBT over current protective circuit | |
| CN208623329U (en) | One kind having the compatible immunity to interference mould group of lightning protection EMC multifunction electromagnetic | |
| CN200983499Y (en) | Thunder-prevention circuit of monitoring and collection device network interface | |
| CN214850474U (en) | Surge protection circuit for preventing lightning stroke of RF port | |
| CN2664252Y (en) | A lightning protector | |
| CN209344773U (en) | Surging protection circuit | |
| CN209488171U (en) | A kind of 485 communication bus lightning protection circuits for mqtt gateway | |
| CN2682711Y (en) | A protective device | |
| CN206807003U (en) | A kind of follow-on RJ45 interfaces surging protection circuit | |
| CN112952785A (en) | Surge protection circuit | |
| CN203261018U (en) | Lightning protection device for mega-byte network | |
| CN1043417A (en) | Telephone protection circuit | |
| CN213151905U (en) | Protection circuit, lightning protection device and electronic equipment of weak current power supply port |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |