Patterned ground structure filter designs with improved performance

Patent metadata

Field	Value
Publication number	US-10244618-B2
Application number	US-201715631336-A
Country	US
Kind code	B2
Filing date	Jun 23, 2017
Priority date	Oct 29, 2015
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

Disclosed herein are printed circuit boards (PCBs) with patterned ground structure filters and data storage devices comprising such PCBs. Each PCB comprises a resonator having an L-shape or a zig-zag shape in a plane of the printed circuit board and at least one signal trace. The resonator has a first dimension and a second dimension in the plane of the printed circuit board. A portion of the at least one signal trace is situated over the resonator and is separated by a distance from the resonator by a dielectric material. In some embodiments, at least part of the portion of the at least one signal trace extends in a same direction as the first dimension (in the case of an L-shaped resonator) or tracks the zig-zag shape of the resonator (in the case of a zig-zag-shaped resonator).

First claim

What is claimed is:

1. A printed circuit board, comprising:
a resonator in a first plane of the printed circuit board, the resonator having an L-shape in the first plane, the resonator having a first dimension in a first direction and a second dimension in a second direction in the first plane; and
a signal trace in a second plane of the printed circuit board, the second plane being parallel to and over the first plane, wherein:
a portion of the signal trace is situated over the resonator,
the portion of the signal trace is separated by a distance from the resonator by a dielectric material,
a first part of the portion of the signal trace extends in the first direction, and
a second part of the portion of the signal trace extends in the second direction.

2. The printed circuit board recited in claim 1 , wherein the signal trace is a differential signal trace.

3. The printed circuit board recited in claim 1 , wherein the signal trace is a single-ended signal trace.

4. The printed circuit board recited in claim 1 , wherein the distance is between approximately 30 μm and 100 μm.

5. The printed circuit board recited in claim 1 , wherein the first dimension is between approximately 4 mm and 9 mm.

6. The printed circuit board recited in claim 1 , wherein a length of the portion of the signal trace situated over the resonator is between approximately 4 mm and 9 mm.

7. The printed circuit board recited in claim 1 , wherein the dielectric material is a first dielectric material, and wherein the resonator comprises:
a first shield layer comprising a first conductive material;
a second shield layer that is spaced from the first shield layer by a second dielectric material, the second shield layer comprising a second conductive material, wherein the second shield layer has a first outer portion and a first middle portion, the first middle portion being spaced from the first outer portion on all sides by the second dielectric material when viewed from a top view;
a first anchor element extending between and coupled to the first shield layer and the second shield layer, wherein the first anchor element extends through the first middle portion of the second shield layer; and
a second anchor element extending between and coupled to the first shield layer and the second shield layer, wherein the first anchor element extends through the first middle portion of the second shield layer.

8. A data storage device comprising the printed circuit board recited in claim 1 .

9. A printed circuit board, comprising:
a first resonator in a first plane of the printed circuit board, the first resonator having an L-shape in the first plane, the first resonator having a first dimension in a first direction and a second dimension in a second direction in the first plane;
a signal trace in a second plane of the printed circuit board, the second plane being parallel to and over the first plane;
a second resonator in a third plane of the printed circuit board, the second resonator being identical to the first resonator and positioned directly above or below the first resonator such that an orientation of the second resonator in the third plane is identical to an orientation of the first resonator in the first plane; and
a via connecting the first resonator to the second resonator,
wherein:
a portion of the signal trace is situated over the first resonator,
the portion of the signal trace is separated by a distance from the first resonator by a dielectric material,
at least part of the portion of the signal trace extends in the first direction, and
the second plane is situated between the first and third planes.

10. The printed circuit board recited in claim 9 , wherein the part of the portion of the signal trace includes all of the portion of the signal trace situated over the resonator.

11. The printed circuit board recited in claim 9 , wherein the part is a first part, and wherein a second part of the portion of the signal trace situated over the resonator extends in the second direction.

12. The printed circuit board recited in claim 9 , wherein the dielectric material is a first dielectric material, and wherein each of the first and second resonators comprises:
a first shield layer comprising a first conductive material;
a second shield layer that is spaced from the first shield layer by a second dielectric material, the second shield layer comprising a second conductive material, wherein the second shield layer has a first outer portion and a first middle portion, the first middle portion being spaced from the first outer portion on all sides by the second dielectric material when viewed from a top view;
a first anchor element extending between and coupled to the first shield layer and the second shield layer, wherein the first anchor element extends through the first middle portion of the second shield layer; and
a second anchor element extending between and coupled to the first shield layer and the second shield layer, wherein the first anchor element extends through the first middle portion of the second shield layer.

13. A data storage device comprising the printed circuit board recited in claim 9 .

Assignees

• Western Digital Tech Inc

Inventors

• Wallash Albert
• Contreras John
• Nakamura Satoshi
• He Hui

Classifications

• H05K1/0224

  Patterned shielding planes, ground planes or power planes (H05K1/0253 takes precedence) · CPC title

• H01P1/2013

  Coplanar line filters · CPC title

• G11B33/1493

  Electro-Magnetic Interference [EMI] or Radio Frequency Interference [RFI] shielding; grounding of static charges · CPC title

• H05K1/0245 Primary

  Lay-out of balanced signal pairs, e.g. differential lines or twisted lines · CPC title

• H05K1/0225

  Single or multiple openings in a shielding, ground or power plane (H05K1/0227 takes precedence) · CPC title