Shielded flex cable for use in a disk drive

Patent metadata

Field	Value
Publication number	US-9275664-B2
Application number	US-201314106308-A
Country	US
Kind code	B2
Filing date	Dec 13, 2013
Priority date	Dec 13, 2013
Publication date	Mar 1, 2016
Grant date	Mar 1, 2016

Abstract

A flex cable with a shielding layer for use in a disk drive is described. The flex cable connects the actuator to the system electronics. The flex cable has a shielding layer that provides RF shielding for the embedded signal traces. In embodiments the shielding layer is connected to the baseplate or device enclosure ground at one or more selected points on the bracket end of the flex cable that are separated from the signal paths. Embodiments of the shielding layer include rows of apertures or windows that are aligned with selected signal traces such as the read and write signal traces and serve to maintain the desired impedance in the read and write signal traces. In one embodiment the shielding layer extends over a selected portion of the flex cable that includes the bracket end and the area under the first stiffener.

First claim

The invention claimed is:

1. A disk drive comprising:
a baseplate;
a disk rotatably mounted on a spindle attached to the baseplate;
system electronics attached to the baseplate;
a stationary bracket having electrical connections to the system electronics and being attached to the baseplate;
a pivoting actuator that includes a rigid arm mounted on a pivot point and a flexible suspension attached to the rigid arm with a slider mounted on the flexible suspension so that the slider is selectably positionable over the disk by pivoting movement of the actuator; and
a flexible wiring cable connecting the pivoting actuator to the system electronics through the stationary bracket, the flexible wiring cable having first and second ends and being attached to the stationary bracket at the first end and being attached to the pivoting actuator at the second end, the flexible wiring cable having a set of conductive signal traces that are encapsulated inside flexible encapsulation material and are connected to the system electronics and include a signal return trace and a shielding layer of conductive material extending over at least a selected portion of the flexible wiring cable that includes the first end which is attached the stationary bracket, the shielding layer being electrically isolated from the set of conductive signal traces and being electrically connected to the baseplate to provide radio-frequency interference shielding for the set of conductive signal traces.

2. The disk drive of claim 1 wherein the shielding layer includes at least one row of windows that are aligned with a selected signal trace.

3. The disk drive of claim 1 wherein the shielding layer includes at least first and second rows of windows with each row including a plurality of windows arranged in a selected pattern and wherein the first row of windows is aligned with a pair of signal traces for a write signal and the second row of windows is aligned with a pair of signal traces for a read signal.

4. The disk drive of claim 3 wherein the selected pattern of windows contributes to an impedance of the pair of signal traces for the read signal.

5. The disk drive of claim 3 wherein the impedance of the pair of signal traces for the read signal is approximately 100 ohms.

6. The disk drive of claim 1 wherein the shielding layer extends over the selected portion of the flexible wiring cable that includes the first end, a trace pad area and an area under a first stiffener that is attached to the flexible wiring cable adjacent to the stationary bracket, the shielding layer ending before reaching the second end of the flexible wiring cable that is attached to the pivoting actuator and the shielding layer having no electrical connection to the pivoting actuator.

7. The disk drive of claim 1 wherein the shielding layer extends over the selected portion of the flexible wiring cable that includes the first end, and an area under a first metallic stiffener that is attached to the flexible wiring cable adjacent to the stationary bracket, the shielding layer ending before reaching the second end of the flexible wiring cable that is attached to the pivoting actuator and the shielding layer having no electrical connection to the pivoting actuator and wherein the shielding layer provides shielding for the set of conductive signal traces from radio-frequency interference coupled by the first metallic stiffener.

8. The disk drive of claim 1 wherein the shielding layer includes at least one row of apertures that are aligned with a selected signal trace and wherein the apertures have a rectangular shape with rounded corners.

9. The disk drive of claim 1 wherein the shielding layer includes at least first and second rows of windows with each row including a plurality of windows arranged in a selected pattern, wherein the windows have a rectangular shape with rounded corners and wherein the first row of windows is aligned with a pair of signal traces for a write signal and the second row of windows is aligned with a pair of signal traces for a read signal.

10. The disk drive of claim 1 wherein the shielding layer is copper and has a thickness of approximately 10 microns.

Assignees

• HGST Netherlands BV

Inventors

• Contreras John
• Nishiyama Nobumasa
• Wallash Albert

Classifications

• G11B5/486

  with provision for mounting or arranging electrical conducting means or circuits on or along the arm assembly · CPC title

• G11B5/4846 Primary

  Constructional details of the electrical connection between arm and support · CPC title