| 发明名称 |
Telephone subscriber line circuit |
| 摘要 |
A communication line interface circuit including a floating current source supplying a constant current substantially independent of loop length is disclosed. The line interface circuit is provided with circuitry for line supervision and the detection of dial pulse signaling.
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| 申请公布号 |
US4056691(A) |
申请公布日期 |
1977.11.01 |
| 申请号 |
US19770757006 |
申请日期 |
1977.01.05 |
| 申请人 |
BELL TELEPHONE LABORATORIES, INCORPORATED |
发明人 |
FREIMANIS, LAIMONS;MUSSMAN, HARRY EDWARD;SMITH, DEWITT PAUL |
| 分类号 |
H04Q1/32;H04M19/00;H04Q3/42;H04Q3/72;(IPC1-7):H04Q1/28 |
主分类号 |
H04Q1/32 |
| 代理机构 |
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代理人 |
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| 主权项 |
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| 地址 |
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