Caller ID device with a power saving function
US6195421A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 27, 1999 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | May 27, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M2215/0164
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Disclosed is a caller ID device with a power saving function according to the invention. The caller ID device, electrically coupled to a pair of telephone lines together with a telephone, includes a CAS receiver, a current limiting circuitry, an FSK receiver, an FSK mark or space tone detector, a controller and a DC battery. At an off-hook state, the current limiting circuitry can directs an operating current from the pair of telephone lines to the CAS receiver through the telephone for power supply. At an on-hook state, the FSK mark or space tone detector can detect an FSK mark or space signal from the pair of the telephone lines and then output an FSK mark or space detecting signal in response to the received FSK mark or space signal, thereby enabling the controller to activate the FSK receiver ready to receive an FSK demodulate signal from the pair of the telephone lines. As a result, the DC battery used in the inventive caller IC device can have a longer life time even though no additional AC adaptor is installed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.