SE7807783L - ELECTRONIC CIRCUIT IN A TELEPHONE SWITCH FOR POWER SUPPLY OF TELEPHONE CIRCUITS - Google Patents
ELECTRONIC CIRCUIT IN A TELEPHONE SWITCH FOR POWER SUPPLY OF TELEPHONE CIRCUITSInfo
- Publication number
- SE7807783L SE7807783L SE7807783A SE7807783A SE7807783L SE 7807783 L SE7807783 L SE 7807783L SE 7807783 A SE7807783 A SE 7807783A SE 7807783 A SE7807783 A SE 7807783A SE 7807783 L SE7807783 L SE 7807783L
- Authority
- SE
- Sweden
- Prior art keywords
- line
- telephone
- power supply
- electronic circuit
- senses
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M19/00—Current supply arrangements for telephone systems
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Amplifiers (AREA)
- Interface Circuits In Exchanges (AREA)
- Devices For Supply Of Signal Current (AREA)
Abstract
An electric circuit arrangement which is part of a telephone exchange and is connected to a power source for supplying current to the telephone sets connected to the exchange. The circuit arrangement contains two differential amplifiers OP1, OP2, one of which OP1 senses the feed current I to the line by detecting the voltage drop across a resistance r, directly connected to the line. The second differential amplifier OP2 senses any voltage changes across the line Le and sends a control quantity to an emitter sensor T connected in series between the power source so that the line current changes in dependence on the voltage change across the line. The circuit thus acts as a simulated impedance for the transverse line signals. <IMAGE>
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE7807783A SE420039B (en) | 1978-07-13 | 1978-07-13 | Electronic circuit arrangement in a telephone exchange for current supply |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE7807783A SE420039B (en) | 1978-07-13 | 1978-07-13 | Electronic circuit arrangement in a telephone exchange for current supply |
Publications (2)
Publication Number | Publication Date |
---|---|
SE7807783L true SE7807783L (en) | 1980-01-14 |
SE420039B SE420039B (en) | 1981-09-07 |
Family
ID=20335439
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
SE7807783A SE420039B (en) | 1978-07-13 | 1978-07-13 | Electronic circuit arrangement in a telephone exchange for current supply |
Country Status (1)
Country | Link |
---|---|
SE (1) | SE420039B (en) |
-
1978
- 1978-07-13 SE SE7807783A patent/SE420039B/en not_active IP Right Cessation
Also Published As
Publication number | Publication date |
---|---|
SE420039B (en) | 1981-09-07 |
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