| 摘要 |
PURPOSE:To reduce the number of parts and manufacturing steps of a brushless DC motor by controlling the operation of the second drive transistor group at the energizing state time so that the operating voltage of the first drive transistor group at the energizing state time becomes the prescribed value. CONSTITUTION:In the first distribution controller 102, the first drive transistor groups 26-28 are controlled in energization by a voltage/current converter 105 which responds to the outputs of Hall elements 15-17 and inputs a command signal correspondence voltage fed via a voltage/current converter 62 an a current mirror circuit 110 from a command signal 60 and the current detection voltage from a resistor 21, and a differential circuit 104. In the second distribution controller 103, the second drive transistor groups 46-48 are controlled in energization via a differential circuit 108 by the output of a detection comparator 106 which responds to the output of Hall elements 18-20 and compares the operation voltage at the energizing state time of the second drive transistor groups 46-48 with the reference voltage signal obtained from a current mirror circuit 110, and the reduction of the operating voltage is compensated. |
