Patent ID: 6498698
Filing Date: 2002-12-24
Classification: G11B

Abstract:
A method of unlatching an actuator arm from a latch restraining the actuator arm in a head disk assembly connected to a servowriter that includes a first node and a second node, the head disk assembly including a voice coil motor (VCM) coupled to the actuator arm, the VCM including a coil connected between the first node and the second node, the method comprising the steps of:a. applying a voltage between the first node and the second node to cause current to flow through the coil in order to move the actuator arm away from the latch at an actuator arm velocity; b. temporarily activating a VCM velocity control signal to enable a VCM voltage limiting circuit connected in parallel with the coil between the first node and the second node; and c. clamping the voltage applied across the coil to a predetermined VCM voltage level with the enabled VCM voltage limiting circuit in order to decelerate the actuator arm toward a selected actuator arm velocity.