Abstract: A data storage device comprises a disk; a spindle on which the disk is mounted; a spindle motor that rotates the spindle; an actuator arm configured with a recording head; and an actuator that rotates the actuator arm about a pivot to move the actuator arm radially across a disk surface. Control circuitry controls the actuator to move the actuator arm across the disk surface while simultaneously applying an active brake to decelerate the spindle by controlling a driver voltage to be out of phase with a back electromotive force (BEMF) voltage of the spindle motor.

Abstract: A data storage device comprises a disk; a spindle on which the disk is mounted; a spindle motor that rotates the spindle; an actuator arm configured with a recording head; and an actuator that rotates the actuator arm about a pivot to move the actuator arm radially across a disk surface. Control circuitry controls the actuator to move the actuator arm across the disk surface while simultaneously applying an active brake to decelerate the spindle by controlling a driver voltage to be out of phase with a back electromotive force (BEMF) voltage of the spindle motor.

Abstract: Various illustrative aspects are directed to a data storage device comprising one or more disks; a spindle motor for rotating the one or more disks, wherein the spindle motor comprises a plurality of magnetic pole-pairs, and wherein the spindle motor is configured to operate in a plurality of modes, including at least a first mode and a second mode; and one or more processing devices configured to select a reference point for spindle motor interrupt service routines (ISRs), determine a delay time, wherein the delay time is based at least in part on a number of magnetic pole-pairs and a mechanical revolution period of the spindle motor, start a timer at a first ISR, and when the timer is equal to the delay time, switch operation of the spindle motor from the first mode to the second mode.

Abstract: Various illustrative aspects are directed to a data storage device comprising one or more disks; a spindle motor for rotating the one or more disks, wherein the spindle motor comprises a plurality of magnetic pole-pairs, and wherein the spindle motor is configured to operate in a plurality of modes, including at least a first mode and a second mode; and one or more processing devices configured to select a reference point for spindle motor interrupt service routines (ISRs), determine a delay time, wherein the delay time is based at least in part on a number of magnetic pole-pairs and a mechanical revolution period of the spindle motor, start a timer at a first ISR, and when the timer is equal to the delay time, switch operation of the spindle motor from the first mode to the second mode.

Abstract: Various illustrative aspects are directed to a data storage device comprising: a voice coil motor (VCM) and one or more processing devices, configured to actuate the VCM, switch on measuring a back electromotive force (BEMF) from the VCM for intervals of an initial BEMF measurement that are free of spikes in the initial BEMF measurement, and process a measured BEMF signal from the intervals of the initial BEMF measurement that are free of spikes in a change of current term of the initial BEMF measurement.

Abstract: Various illustrative aspects are directed to a data storage device comprising: a voice coil motor (VCM) and one or more processing devices, configured to actuate the VCM, switch on measuring a back electromotive force (BEMF) from the VCM for intervals of an initial BEMF measurement that are free of spikes in the initial BEMF measurement, and process a measured BEMF signal from the intervals of the initial BEMF measurement that are free of spikes in a change of current term of the initial BEMF measurement.

Abstract: Methods and apparatus to reduce the stopping time of a spindle motor are disclosed. An example method includes detecting a dissipation current flowing in a spinning motor; determining when the dissipation current drops below a threshold value; and, in response to the dissipation current dropping below the threshold value, applying a voltage to the motor to increase the dissipation current for a duration. In some examples, the voltage is removed from the motor when the motor reaches a predetermined rotational velocity to avoid reverse rotation.

Abstract: Methods and apparatus to reduce the stopping time of a spindle motor are disclosed. An example method includes detecting a dissipation current flowing in a spinning motor; determining when the dissipation current drops below a threshold value; and, in response to the dissipation current dropping below the threshold value, applying a voltage to the motor to increase the dissipation current for a duration. In some examples, the voltage is removed from the motor when the motor reaches a predetermined rotational velocity to avoid reverse rotation.