| 摘要 |
PROBLEM TO BE SOLVED: To supply common constant currents which are not affected by the wiring resistance of a power supply line in the middle to one or more loads in a remote place. SOLUTION: A remote circuit is provided with a plurality of load drive circuits where resistances and PNP transistors whose one ends are connected to a power supply line are serially connected, and the collector currents of the circuit are supplied to each load. The remote circuit is provided with one extra load drive circuit whose output current can be feeded back to a circuit in hand as feedback currents. The circuit in hand makes the feedback currents flow through a reference resistance to generate a feedback voltage, and the amounts of currents to be sucked from a base signal line to which the bases of the transistors of the load drive circuits are commonly connected are controlled by an error amplifying circuit so that the feedback voltage can be matched with the reference voltage generated by a reference voltage generating circuit. COPYRIGHT: (C)2004,JPO&NCIPI
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