A floppy disk control circuit enables a floppy disk apparatus to operate
at high speed while current consumption is suppressed to no more than 500
mA, i.e. the maximum allowed current of an apparatus using a USB
interface. The floppy disk control circuit outputs a reference clock to a
spindle motor drive circuit that drives the spindle motor in accordance
with the reference clock to rotate a floppy disk. The floppy disk control
circuit outputs a slow reference clock for a low rotational speed
corresponding to the maximum allowed current at the commencement of the
start-up of rotation of the floppy disk and outputs a fast reference
clock for a high rotational speed after lapse of a predetermined time
from the commencement of the start-up of rotation.