Patent ID: 6104153
Filing Date: 2000-08-15
Classification: G11B

Abstract:
A method of operating a spindle motor in a disk drive connectable to a power supply having a fixed DC voltage, the spindle motor including a stator having a plurality of windings and a rotor rotatable at a variable spin-rate, the rotor having an angular position relative to the stator, the disk drive including switching elements coupled to the fixed DC voltage and the plurality of windings, the method comprising the steps of:controlling the switching elements to sequentially apply the fixed DC voltage across a selected combination of the windings to generate a negative torque on the rotor such that a controlled braking operation is performed to decelerate the rotor to a selected spin-rate .omega.1; andcontrolling the switching elements to apply the fixed DC voltage across at least one of the windings after the variable spin-rate is reduced to the selected spin-rate .omega.1 such that a controlled rotor-stopping operation is performed to control the angular position of the rotor when the rotor comes to a stop at the end of the controlled rotor-stopping operation.