摘要 |
A driving circuit for a DC motor in which the accuracy of the voltage applied to the motor when it is driven with a fixed voltage is improved and the fixed voltage is continuously applied for fixed-speed rotation control. The emitter of a motor driving transistor is connected to the first terminal of the DC motor, the other terminal of which serves as a reference terminal. A voltage is supplied between the collector of the transistor and the reference terminal of the motor, and a bias current is supplied to the base of the transistor. A voltage source produces a voltage which is at a fixed level with respect to the potential of the reference terminal of the motor. A diode arrangement, preferably composed of serially connected transistors each of which has its collector and base connected together, passes current between the voltage source and the base of the driving transistor. |