| 摘要 |
PURPOSE: To prolong the life of a battery by providing a spindle motor equipped with a first pole, spindle driver, voice coil motor equipped with a second pole, and a head actuator. CONSTITUTION: In the case of failure of a battery 105, a back electro motive force is generated that takes the form of an AC signal imparted to a spindle motor 110, so that a diode P2 is inversely biased avoiding from flowing in MOFET 136, 146, 141. Instead of it, it is imparted to diodes 161, 162, 163, flowing towards a head actuator 170. Diodes 161, 162, 163 are forward biased until a spindle motor 120 is slowed down to the extent below the threshold value of these diodes. Simultaneously, with the loss of V battery detected by the head saving circuit 171 of the head actuator 170, it occurs that the pole corresponding to the voice coil motor 120 supplies H and L signals, rotating the motor 120, and retreating a read/write head to a safety sector. |
