Opto-coupler interfacing circuit
US4558183A · kind A · utility
14Cited by
8References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1983 |
| Grant date | Dec 10, 1985 |
| Priority date | — |
| Expiry date | Oct 3, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M19/026
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A circuit for interfacing a telephone system, such as a cordless telephone, to telephone lines by the use of opto-couplers, arranged to establish a telephone line loop upon detecting a ringing signal on the telephone lines. Preferably, three opto-couplers are used in varying combinations to provide a standby condition, ringing detection, ringing detection shut-off, telephone line loop connection, incoming audio, and outgoing audio functions. Such a circuit eliminates the use of transformers and relays, while meeting regulations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.