Fallback function telecommunications device
US6980643B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 8, 2001 |
| Grant date | Dec 27, 2005 |
| Priority date | — |
| Expiry date | Jul 9, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M1/2535
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The invention herein is fallback function communications device comprised of a microprocessor, utilized to perform a predetermined operation and processing of a predetermined input signal and then output a corresponding signal, as well as a minimum of one relay circuit having an amplifier circuit and a relay. The terminal at the first side of the relay is connected to the telephone line tip/ring terminal, while the terminal at the second side of the relay is connected to the Public Services Telephone Network (PSTN) tip/ring terminal of the microprocessor. An off-hook detection circuit is connected to the PSTN tip/ring terminal and also connected to the ring detection terminal of the said microprocessor. A dummy load circuit is connected to the tip terminal and the ring terminal of the PSTN. As such, in the event of Voice Over Internet Protocol (VOIP) system failure, the present invention is capable of automatically switching to the PSTN and thereby maintain telephone system operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.