Patent ID: 8174785

Claim:
A hard disk drive, comprising: a disk base; a spindle motor mounted on said disk base for rotating at least one disk to create at least one rotating disk surface with at least one track; a Voice Coil Motor (VCM) including a head stack assembly mechanically coupling a slider to a voice coil for responding to a voice coil control signal for positioning said slider over said track subject to disruption by a Rapid Off Track (ROT) event; an amplifier for amplifying a self-resonant frequency band of said voice coil control signal above an operational frequency band of said VCM used for predicting said ROT events before said head stack assembly delivers said disruption to said slider writing said track; and wherein: said amplifier configured for receiving said voice coil control signal for creating a ROT prediction signal for predicting said ROT event includes said amplifier is further configured for amplifying said voice coil control signal in said self-resonant frequency band for creating said ROT prediction signal.