To prevent a driver IC from being overheated by exactly detecting that an overcurrent flows into the driver IC in a disk device.
A disk device 1 is provided with a spindle motor 3 for rotating a disk 2, a driver IC 6 for supplying a drive voltage to the spindle motor 3, a control section 7 for instructing the driver IC 6 to supply the drive voltage to the spindle motor 3, and a power supply circuit 8 for supplying power to the driver IC 6. The control section 7 is provided with an external difference amplifier 12 which compares a voltage Va supplied from the power supply circuit 8 to the driver IC6 with a reference voltage Vs generated by the power supply circuit 8, and outputs a voltage drop signal b when the voltage Va drops to a value lower than the reference voltage Vs. The control section 7 judges the occurrence of a failure based on the voltage drop signal b output from the difference amplifier 12 and stops the drive voltage to be supplied from the driver IC 6 to the spindle motor 3 when a short circuit occurs in the spindle motor 3 and the overcurrent is generated in the driver IC 6.
KITAGAWA KAZUTO
TAKEDA DAIJI
KAJIKAWA KAZUNORI
ICHIKAWA KAZUHIRO
Katsumi Taguchi
Shinichi Mizuta
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