| 摘要 |
PURPOSE:To compensate the temperature of a counterelectromotive force of a motor while preferably maintaining voltage reducing characteristic and load characteristic by preparing a reference voltage by combining a forward voltage of a temperature compensating diode and a constant output voltage from a constant-voltage source. CONSTITUTION:A voltage drop produced by flowing to a resistor 23 the sum of the collector current of a transistor 18 driven by a voltage applied to a constant- voltage circuit 24 and a temperature compensating diode 20 of the transistor 18, and the collector current of a transistor 17 driven by a voltage applied to an external diode 13 and a temperature compensating diode 19 of the transistor 17 is applied as a reference voltage to a comparator 9. The comparator 9 compares the counterelectromotive force of a motor 8 input to an input 92 with a reference voltage, and applies a control signal to an output circuit 7 to control the rotating speed of the motor 8. |
