DC Motor soft-start circuit

摘要

A DC motor driving circuit includes an exciting coil switching circuit for selecting from among polyphase exciting coils of a brushless motor those coils to be excited and their excitation directions. An excitation current control transistor is connected between a DC excitation current supply line and a DC power supply. A timing signal producing circuit including a time constant circuit is produced so as to limit starting current at the time of starting of the motor. The excitation current control transistor is controlled by the timing signal at the time of starting of the motor.