Browse Prior Art Database

Air Board Controlled Impedance Package

IP.com Disclosure Number: IPCOM000078053D
Original Publication Date: 1972-Nov-01
Included in the Prior Art Database: 2005-Feb-25
Document File: 2 page(s) / 35K

Publishing Venue

IBM

Related People

Garcia, J: AUTHOR [+5]

Abstract

An air dielectric package, modules, cards, boards, provides the lowest possible dielectric constant insulator for isolation of signal wires and allows for individual processing of signal layers. The speed of the electric signals increases as the dielectric constant decreases and conductor spacings (plane-to-plane, line-to-line), for a given impedance and crosstalk, can be decreased. Cumulative tolerances are also avoided.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 2

Air Board Controlled Impedance Package

An air dielectric package, modules, cards, boards, provides the lowest possible dielectric constant insulator for isolation of signal wires and allows for individual processing of signal layers. The speed of the electric signals increases as the dielectric constant decreases and conductor spacings (plane-to-plane, line-to-line), for a given impedance and crosstalk, can be decreased.

Cumulative tolerances are also avoided.

The package (Fig. 1) comprises alternate layers of dielectric 10 and a metal 11 sufficiently rigid to maintain a given air-gap spacing between metallic conductors and their associated grounds planes, where a particularly high degree of impedance control is necessary. The number of layers is determined by the total need for signal wires and input/ output interconnections.

The layers (detailed in Fig. 2) include holes 12, 13 through which interlayer connections pass. In the metal layers the holes 12 have an insulating barrier 14 which isolates the interlayer connections 15 from the metal layer itself, except in the case where connection to the metal layer is desired. The metal layer may have a thin insulator over its entire surface, if desired. The dielectric layer serves as a support for signal wires 16. The layers 10 and 11 are attached to each other at the interlayer connections 15, in such a fashion that the separation of the signal wires 16 from the ground plane is determined by the height of the standoff 17 of the interlayer connection 15 from...