Telephonic communications – Subscriber line or transmission line interface
Patent
1994-11-14
1997-07-15
Zele, Krista M.
Telephonic communications
Subscriber line or transmission line interface
379398, 379413, 379414, H04M 1900
Patent
active
056490097
ABSTRACT:
A circuit and method for sensing and compensating for longitudinal (common mode) signals in a subscriber loop of a telephone system. The circuit and method may include a longitudinal amplifier for sensing a difference between a reference voltage, V.sub.BAT /2, and a longitudinal voltage in the subscriber loop, and for providing four currents, two to each of two current amplifiers in the telephone system subscriber line interface circuit (SLIC). The longitudinal amplifier includes two current mirrors, each for providing two currents of the same polarity and of the same magnitude. The magnitude of the difference between the two currents being provided to each of the current amplifiers is proportional to the voltage difference. When compensation of the longitudinal signals has been achieved, the two voltages are the same and the magnitudes of the four currents are the same.
REFERENCES:
patent: 4357494 (1982-11-01), Chambers, Jr.
patent: 4476350 (1984-10-01), Aull et al.
patent: 4617426 (1986-10-01), Johansson et al.
patent: 4656661 (1987-04-01), Carbrey
patent: 4677667 (1987-06-01), Burns
patent: 4782507 (1988-11-01), Siligoni et al.
patent: 4926473 (1990-05-01), Bahl et al.
patent: 4961219 (1990-10-01), Patel
patent: 5428682 (1995-06-01), Apfel
Enriquez Leonel Ernesto
Uscategui Gabriel Julio
Harris Corporation
Wolinsky Scott
Zele Krista M.
LandOfFree
Differential longitudinal amplifier for a subscriber line interf does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Differential longitudinal amplifier for a subscriber line interf, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Differential longitudinal amplifier for a subscriber line interf will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1497422