发明名称 |
Balanced DC supply for telephone subscriber circuit - has complementary transistors in series with wires and controlled by differential amplifier with battery and inter wire voltage inputs |
摘要 |
<p>The DC supply circuit, for a telephone subscriber circuit, is located between the telephone line and the supply battery. It produces a constant current with the aid of two complementary transistors each in series with one of the wires in the 2-wire telephone line. The base current of these two transistors is modified by a correction circuit so that they operate close to their working point and are balanced. The correction circuit consists of a differential amplifier whose two inputs receive (via two resistive voltage dividers) the voltage across the battery's terminals and the voltage between the wires.</p> |
申请公布号 |
FR2335111(A1) |
申请公布日期 |
1977.07.08 |
申请号 |
FR19750038082 |
申请日期 |
1975.12.12 |
申请人 |
LABO CENTRAL TELECOMMUNICATIONS |
发明人 |
DANIEL MICHEL AUGUSTE FERNAND BOLUS, JEAN-PIERRE CHEVILLON ET PIERRE DENIS PAUL PHILIPPE;CHEVILLON JEAN-PIERRE;PHILIPPE PIERRE DENIS PAUL |
分类号 |
H04M19/00;(IPC1-7):04M19/00 |
主分类号 |
H04M19/00 |
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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