Patent ID: 8179640

Claim:
A hard disk drive, comprising: a disk; a spindle motor for rotating said disk and for generating a back-emf voltage and a back-emf current; a head coupled to said disk; an actuator arm coupled to said head; a voice coil motor coupled to said actuator arm, said voice coil motor for moving said head off of said disk; and, a drive circuit coupled to said voice coil motor for: providing a portion of said back-emf current at a first acceleration value to said voice coil motor when a head velocity is between a first predetermined value and a second predetermined value, and providing a portion of said back-emf current at a second acceleration value to said voice coil motor when the head velocity exceeds the second predetermined value, and providing a portion of said back-emf current at a first deceleration value to said voice coil motor when the head velocity is between a third predetermined value and a fourth predetermined value, and providing a portion of said back-emf current at a second deceleration value to said voice coil motor when the head velocity exceeds the fourth predetermined value.