Patent Leaderboard
USPTO Patent Rankings Data through Dec 31, 2025
Home › Subscriber line interface circuit for a telephone line

Subscriber line interface circuit for a telephone line

US Patent 4275277 · Granted Jun 23, 1981

Estimated economic value: $538,000 ⓘ

Assignee

Inventors

View full patent text on Google Patents →

More Patents by These Inventors

Echo canceller using delta modulation1989
Anti-larsen-effect arrangement in a telephone station equipped with a loudspeake1984
Current mirror circuit1984
Hands free telephone with switchable gain in the two speech signal paths1984
Arrangement for avoiding annoying sustained oscillations in a closed-loop system1984
Electronic subscriber line interface circuit having means to equalize current th1983
Automatic sound level control of telephone station1983
Electronic subscriber junctor1982
Apparatus for detecting the closure of a subscriber's line during ringing1982
Subscriber's connecting network comprising a symmetrical power amplifier for fee1982
Arrangement for processing a delta modulation signal, in particular for decoding1980
Subscriber's circuit with a symmetrical amplifier1980