Apparatus for controlling spindle motor of compact disc utilizing appliance

An apparatus for controlling a spindle motor of a compact disc utilizing appliance, comprising:

• rotation speed detecting means for detecting an actual rotation speed of the spindle motor and outputting a signal having a frequency proportional thereto;
• means for shaping the waveform of the signal output from the rotation speed detecting means to form a rotation speed frequency signal;
• a microcomputer for outputting a reference frequency signal in response to said rotation speed frequency signal and for outputting a control signal to control an input to said spindle motor depending on operating modes of said apparatus, said reference frequency signal being such that, during a track search mode of said apparatus, said reference signal is utilized in forming a signal to the spindle motor, the spindle motor is driven at a determined speed which causes a target track to move at a constant linear velocity with respect to a pick-up;
• means for comparing the reference frequency signal outputted from the microcomputer and the rotation speed frequency signal outputted from the waveform shaping means and outputting control signals;
• means for amplifying and subtracting said control signals so as to output an amplified control signal;
• and
• spindle motor drive control signal switching means for selecting, as the input to said spindle motor under the control of the control signal from the microcomputer, said amplified control signal when said apparatus is in a track search mode, versus selecting as said input a normal mode operation drive control signal when said apparatus is in the normal operation mode to thereby cause the spindle motor to be rotating at said determined speed upon entering said normal operation mode from said track search mode, thus permitting rapid accessing of information immediately upon entering said normal operation mode from said track search mode.