Circuit for detecting current variations

Details Circuit for detecting current variations Circuit for detecting current variations

1987-03-24

1988-03-15

Ng, Jin F.

Telephonic communications

Supervisory or control line signaling

Using line or loop condition detection

379377, H04M 322

Patent

active

047318295

ABSTRACT:
The circuit of the present invention detects variations of a current I.sub.L flowing in a telephone line LL. A low-value resistor r is connected in series with line LL. A constant voltage generator is connected across this resistor. The current Is applied to resistor r by the contant voltage generator varies as a function of I.sub.L. This being so, a measurement of the variations of Is will reflect variations of I.sub.L and, therefore, can be used to detect both amplitude and directional variations of I.sub.L.

REFERENCES:
patent: 3835258 (1974-09-01), Le Cardonnel
patent: 4127747 (1978-11-01), Levi
patent: 4287393 (1981-09-01), Reuvekamp
patent: 4429186 (1984-01-01), Gartner
patent: 4454477 (1984-06-01), Joffe
patent: 4490580 (1984-12-01), Nagashima
patent: 4524246 (1985-06-01), Meza
patent: 4591663 (1986-05-01), Sullivan

Affiliated with

Also associated with

Rating

Circuit for detecting current variations does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Circuit for detecting current variations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Circuit for detecting current variations will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1930672