Abstract: A rotation control apparatus for controlling a rotation of a recording medium in which a signal modulated in a run length limited code has been recorded in concentric or spiral information tracks at a constant linear velocity. An inversion time detecting circuit alternately detects a maximum or minimum transition interval of a reproduced digital signal from its rise transition to its fall transition, and a maximum or minimum transition interval of the reproduced digital signal from its fall transition to its rise transition, so as to thereby produce a transition interval signal corresponding to each of the detected maximum or minimum values. A motor drive circuit drives a motor in such a direction as to reduce a difference between the value of the transition interval signal and a predetermined value.