US4801905A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microstrip shielding system
Assignee: Agilent Technologies Inc
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Filing: 1987-04-23
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Granted: 1989-01-31
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Expires: 2007-04-23
Abstract
Abstract A shielded printed circuit board system is described in which a microstrip transmission line secured to the surface of a dielectric substrate between ground planes is shielded to isolate the microstrip and inhibit the escape of electromagnetic radiation. This system reduces crosstalk in printed circuit boards and also reduces coupling of external fields into the signal path, thus allowing more sensitive measurements. The shield member is conductive and includes a body section and downwardly depending leg members. The leg members are secured to ground planes on each side of the microstrip transmission line. In another embodiment a dimensionally stable support plate (e.g., an aluminum plate) is secured over the shield member.
Inventors
- 👤 Alvin G. Becker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:52
CPC Classifications
H; H01; H01P; H01P3/00; H01P3/02; H01P3/08; H01P3/081
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
159 words
A shielded printed circuit board system comprising: (a) a printed circuit board comprising a conductive microstrip transmission line secured to one surface of a dielectric substrate between ground planes separated from said microstrip line on said substrate; and (b) a conductive shield member spaced above said microstrip transmission line, wherein said shield member includes downwardly depending leg members secured to said ground planes; wherein said shield member includes an elongated body section having first and second edges; wherein said body section is generally planar and is disposed parallel to said microstrip transmission line; wherein there are a plurality of said downwardly depending leg members attached to said first edge of said body section and a plurality of said leg members attached to said second edge of said body section; wherein said leg members are integral with said body section and are springy; wherein said shield member is adapted to inhibit escape of electromagnetic radiation from said microstrip transmission line.
Claim 2
Dependent Claim
159 words
A shielded printed circuit board system comprising: (a) a printed circuit board comprising a conductive microstrip transmission line secured to one surface of a dielectric substrate between ground planes separated from said microstrip line on said substrate; and (b) a conductive shield member spaced above said microstrip transmission line, wherein said shield member includes downwardly depending leg members secured to said ground planes; wherein said shield member includes an elongated body section having first and second edges; wherein said body section is generally planar and is disposed parallel to said microstrip transmission line; wherein there are a plurality of said downwardly depending leg members attached to said first edge of said body section and a plurality of said leg members attached to said second edge of said body section; wherein said leg members are integral with said body section and are springy; wherein said shield member is adapted to inhibit escape of electromagnetic radiation from said microstrip transmission line.
Claim 3
Dependent Claim
22 words
A shielded printed circuit board system in accordance with claim 1, wherein said shield member comprises an alloy of beryllium and copper.
Claim 4
Dependent Claim
17 words
A shielded printed circuit board system in accordance with claim 1, wherein said shield member comprises tin.
Claim 5
Dependent Claim
37 words
A shielded print circuit board system in accordance with claim 1, wherein said shield member is composed of a metal selected from the group consisting of copper, tin, brass, steel, stainless steel, and aluminum, or alloys thereof.
Claim 6
Dependent Claim
41 words
A shielded printed circuit board system in accordance with claim 1 wherein said leg members include upper and lower ends, wherein said upper ends are attached to said body section; and wherein said lower ends are narrower than said upper ends.
Claim 7
Dependent Claim
24 words
A shielded printed circuit board system in accordance with claim 1, wherein the spacing between adjacent leg members is less than about 0.5 inch.
Claim 8
Dependent Claim
17 words
A shielded printed circuit board system in accordance with claim 5, wherein said leg members are triangular.
Claim 9
Dependent Claim
17 words
A shielded printed circuit board system in accordance with claim 1, wherein said leg members are rectangular.
Claim 10
Dependent Claim
27 words
A shielded printed circuit board system in accordance with claim 1, wherein said shield member has a thickness in the range of about 0.002 to 0.02 inch.
Claim 11
Dependent Claim
37 words
A shielded printed circuit board system in accordance with claim 1, wherein said body section of said shield member is spaced above said microstrip transmission line a distance in the range of about 0.02 to 0.025 inch.
Claim 12
Dependent Claim
32 words
A shielded printed circuit board system in accordance with claim 1, wherein said leg members comprise an alloy of beryllium and copper, and wherein said leg members bear an overlayer comprising tin.
Claim 13
Dependent Claim
19 words
A shielded printed circuit board system in accordance with claim 1, wherein said leg members comprise continuous wall sections.
Claim 14
Dependent Claim
57 words
A shielded printed circuit board system in accordance with claim 1, wherein said printed circuit board includes a plurality of said microstrip transmission lines parallel to each other; wherein each said microstrip transmission line is secured to said dielectric substrate between ground planes; and wherein each said microstrip transmission line is shielded by a said shield member.
Claim 15
Dependent Claim
38 words
A shielded printed circuit board system in accordance with claim 13, wherein each said shield member comprises a metal selected from the group consisting of beryllium-copper alloy, copper, brass, steel, stainless steel, tin, and aluminum, or alloys thereof.
Claim 16
Dependent Claim
31 words
A shielded printed circuit board system in accordance with claim 13, further comprising a dimensionally stable support member secured to said printed circuit board and being disposed over said shield member.
Claim 17
Dependent Claim
19 words
A shielded printed circuit board system in accordance with claim 15, wherein said support member comprises an aluminum plate.
Claim 18
Dependent Claim
139 words
A shielded printed circuit board system comprising: (a) a printed circuit board comprising a conductive microstrip transmission line secured to one surface of a dielectric substrate between ground planes separated from said microstrip line on said substrate; (b) a conductive shield member spaced above said microstrip transmission line for inhibiting escape of electromagnetic radiation from said microstrip transmission line; wherein said shield member comprises an elongated, generally planar body section having first and second opposite side edges; wherein said body section is disposed parallel to said microstrip transmission line; wherein downwardly projecting leg members are integral with each of said side edges of said body section; wherein said leg members are springy and are secured to said ground planes; and (c) a dimensionally stable support plate secured to said printed circuit board and being disposed over said shield member.
Claim 19
Dependent Claim
139 words
A shielded printed circuit board system comprising: (a) a printed circuit board comprising a conductive microstrip transmission line secured to one surface of a dielectric substrate between ground planes separated from said microstrip line on said substrate; (b) a conductive shield member spaced above said microstrip transmission line for inhibiting escape of electromagnetic radiation from said microstrip transmission line; wherein said shield member comprises an elongated, generally planar body section having first and second opposite side edges; wherein said body section is disposed parallel to said microstrip transmission line; wherein downwardly projecting leg members are integral with each of said side edges of said body section; wherein said leg members are springy and are secured to said ground planes; and (c) a dimensionally stable support plate secured to said printed circuit board and being disposed over said shield member.
Claim 20
Dependent Claim
34 words
A shielded printed circuit board system in accordance with claim 17, wherein said shield member comprises a metal selected from the group consisting of beryllium-copper alloy, copper, brass, steel, stainless steel, tin, and aluminum.
Claim 21
Dependent Claim
31 words
A shielded printed circuit board system in accordance with claim 17, wherein said leg members include upper and lower ends, and wherein said upper ends are attached to said body section.
Claim 22
Dependent Claim
17 words
A shielded printed circuit board system in accordance with claim 19, wherein said leg members are triangular.
Claim 23
Dependent Claim
57 words
A shielded printed circuit board system in accordance with claim 17, wherein said printed circuit board includes a plurality of said microstrip transmission lines parallel to each other; wherein each said microstrip transmission line is secured to said dielectric substrate between ground planes; and wherein each said microstrip transmission line is shielded by a said shield member.
Claim 24
Dependent Claim
27 words
A shielded printed circuit board system in accordance with claim 17, wherein said shield member has a thickness in the range of about 0.002 to 0.02 inch.
Claim 25
Dependent Claim
44 words
A shielded printed circuit board system in accordance with claim 17, wherein said body section of said shield member is disposed parallel to said microstrip transmission line and is spaced above said line a distance in the range of about 0.02 to 0.25 inch.
Claim 26
Dependent Claim
19 words
A shielded printed circuit board system in accordance with claim 17, wherein said leg members comprise continuous wall sections.
Claim 27
Dependent Claim
32 words
A shielded printed circuit board system in accordance with claim 17, wherein said support plate comprises an aluminum plate which is secured to said printed circuit board by means of threaded fasteners.
Claim 28
Dependent Claim
30 words
A shielded printed circuit board system in accordance with claim 25, wherein said aluminum plate includes downwardly projecting spacer members which contact said ground planes on said printed circuit board.
Claim 29
Independent Claim
129 words
A method for shielding a conductive microstrip transmission line secured to one surface of a dielectric substrate between ground planes separated from said microstrip line on said substrate wherein said shield member inhibits escape of electromagnetic radiation from said microstrip transmission line, said method comprising the steps of: (a) providing a conductive shield member which comprises an elongated, generally planar body section having first and second opposite side edges and downwardly depending leg members integral with said first and second side edges of said body section; wherein said leg members are springy; and (b) securing said leg members of said shield member to said ground planes on each side of said microstrip transmission line in a manner such that said body section is disposed parallel to said transmission line.
Claim 30
Independent Claim
129 words
A method for shielding a conductive microstrip transmission line secured to one surface of a dielectric substrate between ground planes separated from said microstrip line on said substrate wherein said shield member inhibits escape of electromagnetic radiation from said microstrip transmission line, said method comprising the steps of: (a) providing a conductive shield member which comprises an elongated, generally planar body section having first and second opposite side edges and downwardly depending leg members integral with said first and second side edges of said body section; wherein said leg members are springy; and (b) securing said leg members of said shield member to said ground planes on each side of said microstrip transmission line in a manner such that said body section is disposed parallel to said transmission line.
Claim 31
Dependent Claim
25 words
A method in accordance with claim 27, wherein there are a plurality of said leg members attached to each said edge of said body section.
Claim 32
Dependent Claim
30 words
A method in accordance with claim 27, wherein said shield member comprises a metal selected from the group consisting of beryllium-copper alloy, copper, tin, brass, steel, stainless steel, and aluminum.
Claim 33
Dependent Claim
39 words
A method in accordance with claim 27, wherein said printed circuit board includes a plurality of said microstrip transmission lines and a plurality of said shield members, and wherein each said line is shielded by a said shield member.
Claim 34
Dependent Claim
13 words
A method in accordance with claim 28, wherein said leg members are triangular.
Claim 35
Dependent Claim
24 words
A method in accordance with claim 27, further comprising securing a dimensionally stable support plate to said printed circuit board over said shield member.
Claim 36
Dependent Claim
23 words
A method in accordance with claim 32, wherein said support plate is secured to said printed circuit board by means of threaded fasteners.
Claim 37
Dependent Claim
13 words
A method in accordance with claim 32, wherein said support plate comprises aluminum.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-31 | 1992-08-01 | 1993-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-31 | 1996-08-01 | 1997-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-31 | 2000-08-01 | 2001-01-31 | $7700.00 | Window Closed / Lapsed |