To provide a disc drive which stops rotation of a DC motor 2 by determining a failure due to short-circuit which happens in the DC motor of the rotation drive source of a disc as quickly as possible.
A control section 10 for controlling the entire system of a disc drive is provided with a rotational speed judging section 18 for judging the deviation of rotational speed from a reference rotational speed in which the linear speed becomes constant at the reading position of a disc 1 and outputting a judgment signal, a drive control means 21 for controlling the disc 1 to the reference rotational speed by controlling a driver IC 22 based on the judgment signal, a comparison means 19 for outputting a high-voltage detection signal when the input voltage to a DC motor 2 detected by a voltage detector 23 exceeds a threshold, and a failure judgment means 20 for commanding a drive control means 21 to stop rotation of the DC motor 2 by delivering a failure signal when the rotational speed judging means 18 is outputting a judgment signal that the rotational speed of the disc 1 is below the reference rotational speed under a state where the high-voltage detection signal is outputted.
KAJIKAWA KAZUNORI
FUKUI TOSHIAKI
KITAGAWA KAZUTO
TAKEDA DAIJI
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