Patent ID: 7660067

Claim:
A disk drive comprising: a disk; a head coupled to a distal end of an actuator arm; a voice coil motor (VCM) operable to rotate the actuator arm about a pivot to actuate the head radially over the disk, the VCM comprising a coil; a ramp; and control circuitry operable to: measure a load resistance of the coil prior to executing a load operation, wherein the load operation moves the actuator arm off the ramp to load the head onto the disk; measure a calibrated ambient temperature (Tcal_amb) using a temperature sensor; measure a calibrated ambient resistance (Rcal_amb) of the coil at the calibrated ambient temperature (Tcal_amb); and convert the load resistance of the coil into an initial coil temperature estimate according to: 1 α ⁢ ( Rcoil - R ⁢ cal ⁢ _ ⁢ amb ) + T ⁢ cal_amb where: α is a coefficient; and Rcoil is the load resistance of the coil.