CN2149733Y - Joint element for telephone exchange - Google Patents
Joint element for telephone exchange Download PDFInfo
- Publication number
- CN2149733Y CN2149733Y CN 93214955 CN93214955U CN2149733Y CN 2149733 Y CN2149733 Y CN 2149733Y CN 93214955 CN93214955 CN 93214955 CN 93214955 U CN93214955 U CN 93214955U CN 2149733 Y CN2149733 Y CN 2149733Y
- Authority
- CN
- China
- Prior art keywords
- impedance
- resistance
- amplifier
- utility
- model
- 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.)
- Expired - Lifetime
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- Interface Circuits In Exchanges (AREA)
- Amplifiers (AREA)
Abstract
The utility model relates to a joint element for two input impedance telephone exchangers, which is composed of an impedance network which is composed of an operational amplifier and a plurality of resistors. The utility model is characterized in that two input terminals of the operational amplifier are respectively connected with a pair of resistance impedance networks with an equal resistance value. A circuit can enhance the ring current intercepting effect, and does not influence the input impedance in normal conversation. The utility model is suitable for thick-film circuit designs.
Description
The utility model relates to a kind of two input impedance parts that are used for the exchange interface parts.
Existing exchange interface parts have two amplifiers to form an impedance before amplifier, form two impedance interfaces parts of another impedance after the amplifier.When shortcoming is second impedance after forming amplifier because a part of signal is through amplifier, another partly signal therefore produce distorted signals without amplifier, simultaneously the frequency response of amplifier etc. is required relatively stricter.
The purpose of this utility model is to provide a kind of two input impedance formula interface units that have only an amplifier, both can improve subscriber line circuit greatly and cut the ringing-current effect, the input impedance when not influencing normal talking again simultaneously, the deficiency of improvement prior art.
The purpose of this utility model is to realize as follows: two inputs at operational amplifier connect pairing in twos and resistive impedance lattice network that resistance equates, and wherein resistance is R
1=R
1', R
2=R
2', R
3=R
3', R
4=R
4', R
5=R
5', R
4Be the negative feedback resistor of amplifier 3, resistance R
4The normal phase input end of ' UNICOM amplifier 3 and ground, input impedance R
XDifference UNICOM resistance R
2And R
2'.
Employing has good detection ring off-hook work effect at the two input impedance formula interface units that utility model provides.
The utility model is described in further detail below in conjunction with accompanying drawing.
Accompanying drawing is circuit theory diagrams of the present utility model.
With reference to accompanying drawing, resistance R
1', meet output audio signal source V
1, relay R EL one end connection electrical resistance R
1, R
5, R
3, the other end can connect 1 end or 2 ends respectively, can connect feed dc signal source V respectively
3Or bell signal source V
2, the output V of amplifier 3
OutWhen relay R EL connects 1 end, as resistance R
1, R
2, R
3, R
4During for a certain determined value, then input impedance resistance R
XIt also is certain value.When relay R EL connected 2 ends, at this moment circuit had two impedances, and working impedance is thousands of ohms, is normal operating conditions when relay R EL connects 1 end, and impedance is 600 ohm.
The utility model is through test of many times, and electrical quantity is good, and reliable operation and cost are very low.
Claims (1)
1, a kind of two input impedance telephone exchange interface units, it comprises the impedance network circuit that operational amplifier (3), some resistance constitute, it is characterized in that: two inputs at operational amplifier connect pairing in twos and resistive impedance lattice network that resistance equates, and wherein resistance is (R
1)=(R
1'), (R
2)=(R
2'), (R
3)=(R
3'), (R
4)=(R
4'), (R
5)=(R
5'), (R
4) be the negative feedback resistor of amplifier (3), resistance (R
4') normal phase input end of UNICOM's amplifier (3) and ground, input impedance (R
x) the difference resistance (R of UNICOM
2) and (R
2').
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 93214955 CN2149733Y (en) | 1993-06-08 | 1993-06-08 | Joint element for telephone exchange |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 93214955 CN2149733Y (en) | 1993-06-08 | 1993-06-08 | Joint element for telephone exchange |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2149733Y true CN2149733Y (en) | 1993-12-15 |
Family
ID=33795593
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 93214955 Expired - Lifetime CN2149733Y (en) | 1993-06-08 | 1993-06-08 | Joint element for telephone exchange |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2149733Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111917920A (en) * | 2020-08-12 | 2020-11-10 | 上海剑桥科技股份有限公司 | Intelligent loop holding device |
-
1993
- 1993-06-08 CN CN 93214955 patent/CN2149733Y/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111917920A (en) * | 2020-08-12 | 2020-11-10 | 上海剑桥科技股份有限公司 | Intelligent loop holding device |
| CN111917920B (en) * | 2020-08-12 | 2022-02-08 | 上海剑桥科技股份有限公司 | Intelligent loop holding device |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C53 | Correction of patent for invention or patent application | ||
| COR | Change of bibliographic data |
Free format text: CORRECT: PATENTEE ADDRESS; FROM: BEIJNG CITY LEIMING ELECTRONICS ENGINEERING CO.,LTD TO: TIANJIN CITY MINGDA SERVICE ENGINEERING CO., LTD. |
|
| CP01 | Change in the name or title of a patent holder |
Patentee after: Tianjin Mingda service engineering company Patentee before: Beijing thunderous Engineering Electronics Company |
|
| C53 | Correction of patent for invention or patent application | ||
| COR | Change of bibliographic data |
Free format text: CORRECT: PATENTEE; FROM: TIANJIN CITY MINGDA SERVICE ENGINEERING CO., LTD. TO: BEIJING HAIKUO ELECTRONIC CO., LTD |
|
| CP03 | Change of name, title or address |
Address after: 100085 room 509, building 5, Fu Lou Road, 11, Haidian District Patentee after: Beijing haikuo electronic Limited by Share Ltd Address before: No. 436 West Nankai District Road, Anshan Patentee before: Tianjin Mingda service engineering company |
|
| C56 | Change in the name or address of the patentee |
Owner name: LIU HAIXIAN Free format text: FORMER NAME OR ADDRESS: BEIJING SEA-WIDE E-CO., LTD. |
|
| CP03 | Change of name, title or address |
Address after: 100041 Beijing Shijingshan Haite garden building 205 room 44 Patentee after: Liu Haixian Address before: 100085, Haidian District Development Zone, 11 Rd Road, Fu Fu Road, building 5, room 509 Patentee before: Beijing haikuo electronic Limited by Share Ltd |
|
| C17 | Cessation of patent right | ||
| CX01 | Expiry of patent term |