CONSTANT CURRENT CIRCUIT FOR CHARGE, AND CHARGING APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a low cost constant current circuit for charge where temperature dependence of a charging current is small, and a charging apparatus provided with an overcharge preventing function using the constant current circuit for charge.

SOLUTION: There are provided: a first transistor and second transistor having the same polarity where a base and an emitter are connected with each other, and a collector and the base are connected with each other; a diode of which one end is connected to the base of the first transistor in the forward direction; a first resistance element connected in series between the other end of the diode and the emitter of the first transistor; and a second resistance element of which one end is connected to a node between the collector of the first transistor and the base of the second transistor. A temperature change of a voltage between the base and emitter of the first transistor is canceled by a temperature change of the diode.

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