Protection circuit for use with a telephone appliance and method

Details Protection circuit for use with a telephone appliance and method Protection circuit for use with a telephone appliance and method

1998-05-06

2000-07-11

Isen, Forester W.

Telephonic communications

Subscriber line or transmission line interface

Protective circuit

379399, 379413, 361 94, H04M 1100, H02H 326

Patent

active

060884460

ABSTRACT:
Protection circuitry for use with a modem is provided that detects excessive voltage between the tip and ring lines of a telephone subscriber loop when the modem is off-hook. When the over-voltage condition is detected, a switch is active, creating a circuit path that directs current away from the DC-holding circuit of the modem, thereby protecting the modem. The protection circuit of the present invention may be implemented using a minimal number of simple and inexpensive components.

REFERENCES:
patent: 3903375 (1975-09-01), DeWit
patent: 4317964 (1982-03-01), Biggs et al.
patent: 4408248 (1983-10-01), Bulley et al.
patent: 4456940 (1984-06-01), Hammerberg et al.
patent: 4603234 (1986-07-01), Huet et al.
patent: 4644437 (1987-02-01), Robe
patent: 4709296 (1987-11-01), Hung et al.
patent: 4723267 (1988-02-01), Jones et al.
patent: 4758920 (1988-07-01), McCartney
patent: 4862309 (1989-08-01), Tojo et al.
patent: 4876620 (1989-10-01), Borkowicz
patent: 4947426 (1990-08-01), Montano
patent: 4947427 (1990-08-01), Rosch et al.
patent: 4958371 (1990-09-01), Damoci et al.
patent: 5042065 (1991-08-01), Kim
patent: 5125027 (1992-06-01), Blaszykowski et al.
patent: 5140631 (1992-08-01), Stahl
patent: 5369687 (1994-11-01), Farkas
patent: 5532898 (1996-07-01), Price
patent: 5675640 (1997-10-01), Tappert et al.
patent: 5696660 (1997-12-01), Price
patent: 5777836 (1998-07-01), Price et al.
patent: 5802151 (1998-09-01), Bevill, Jr. et al.
patent: 5809068 (1998-09-01), Johnson

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