CHARGING AND DISCHARGING CONTROL CIRCUIT AND CHARGING TYPE POWER SUPPLY DEVICE

摘要

PURPOSE: A charging and discharging control circuit and a charging type power supply device are provided to control charging/discharging of a battery unit with the secondary batteries connected in series. CONSTITUTION: A charging and discharging control circuit and a charging type power supply device comprises the following units. A constant current circuit of a circuit for detecting removal of a middle terminal(5) is installed in a terminal to which the secondary battery(3) of a charging/discharging control circuit is connected. The constant current circuit is made of a depletion type MOS transistor and a resistor connected between the gate and source terminals of the depletion MOS transistor.