Disk device with multi-layer flexible printed wiring board mounted to actuator block

A disk device comprising:

• a disk-shaped recording medium including a recording layer;
• a magnetic head configured to process information on the recording medium;
• and
• an actuator assembly supporting the magnetic head to be movable relative to the recording medium,
• wherein the actuator assembly comprises a rotatable actuator block, a plurality of suspension assemblies extending from the actuator block and at least one of the suspension assemblies supporting the magnetic head, and a flexible printed wiring board mounted on the actuator block;
• the flexible printed wiring board comprises:
• a base insulation layer;
• a plurality of first wirings on the base insulation layer;
• an intermediate insulation layer overlapped with the first wirings and the base insulation layer;
• a plurality of connection pads on the intermediate insulation layer;
• a cover insulation layer overlapped with the connection pads and the intermediate insulation layer and including a plurality of openings through which the connection pads are exposed to the cover insulation layer;
• and
• conductive vias electrically connecting the first wirings to at least a part of the connection pads respectively, the conductive vias being arranged to overlap with the connection pads in a thickness direction of the flexible printed wiring board.