| 摘要 |
PROBLEM TO BE SOLVED: To start or stop rotation of a recording medium at high speed. SOLUTION: A DSP 10 outputs an SPSB signal being a start signal of a spindle motor 2 to a spindle driver 15 and a monomulti vibrator 16. The mono- multi vibrator 16 outputs a rectangular wave of low of a prescribed period to a base of an NPN transistor 17. In the NPN transistor 17, as voltage inputted to the base is reduced, impedance between a collector and an emitter is made larger. Then, in the spindle motor 2, as a current inputted from the spindle driver 15 is made smaller, the motor is rotated with low acceleration. And when a signal outputted to the base of the NPN transistor 17 from the mono- multi vibrator 16 is restored to high, the impedance between the collector and the emitter is made smaller, and as the current inputted from the spindle driver 15 is made larger, the spindle motor 2 is rotated with the high acceleration. |
