| 摘要 |
Serial regulation module for telephone lines. The module which is the subject of the invention, for use on analogue lines of the switched telephone network, is for the purpose of guaranteeing a minimum voltage between two specific points of this network for any loop current and independently of the load connected at the subscriber end, including when faced with the existence of a short circuit. This is achieved by means of the functional combination of two circuits, a series regulator circuit 1 and a voltage sensor circuit 2 which checks the first one, both produced by means of discrete components. In practice, in the case of the series regulator 1, two transistors T1 and T2 connected to a capacitor C1 and resistor R1 as fundamental components and a set of de- polarisation diodes D1 to D4 in addition to a bidirectional device Z1 for protection of the circuit against electrical discharges. As for the sensor circuit 2, in addition to a voltage divider R7-R8 it incorporates a thermal compensation, R2- R3, and NTC, R4, network, a fine voltage adjustment P1-R5 and a limiter limiting the current of the transistor T3 for actuating the current-regulator circuit 1 formed by transistor T4 and resistor R6. <IMAGE>
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