Browse Prior Art Database

Double-Sided Edge-Connector Interface

IP.com Disclosure Number: IPCOM000119910D
Original Publication Date: 1991-Mar-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 2 page(s) / 72K

Publishing Venue

IBM

Related People

Miersch, EF: AUTHOR

Abstract

A technique for connecting different levels of packaging by combining existing card-on-board technologies with wire bonding an interface solution between two packaging levels is described, which is equivalent to providing double-sided TAB (tape automated bonding) edge connectors. The technique includes the use of the PWB-card technology to package a first level thin film carrier with conducting substrate (TFCCS) into a second level package, where it replaces a double-sided flex-foil, when it is combined with wire bonding by using existing technologies.

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Double-Sided Edge-Connector Interface

      A technique for connecting different levels of packaging
by combining existing card-on-board technologies with wire bonding an
interface solution between two packaging levels is described, which
is equivalent to providing double-sided TAB (tape automated bonding)
edge connectors.  The technique includes the use of the PWB-card
technology to package a first level thin film carrier with conducting
substrate (TFCCS) into a second level package, where it replaces a
double-sided flex-foil, when it is combined with wire bonding by
using existing technologies.

      A structure is provided wherein a PWB Interface (PWBI) is glued
to a base plate.  Made in conventional card technology with a 50-mil
plated through-hole (PTH) pitch, ground plane and double-sided
surface wiring, it can provide as a ring or in single-sided pieces a
16-mil wire bond pitch with 3 rows of 50-mil PTH's.  Here 2
lines/channel (2L/C) are needed.  With four 50-mil PTH rows a
12.5-mil (250 mm) wire bond pitch (3L/C) seems possible.  Both
solutions provide more wire bonds than needed presently for the Monza
TFCCS requirements.  Better card technologies will improve the wire
bond pitch further and guarantee extendibility.

      The electrical situation is considerably better than the one
using pin-in-hole solutions, as the pins can be eliminated.  From a
cooling point of view and housing point of view, it is also much
better.  The base plate can be used in combination with fixtures in
the corner of the plate to press the TFCCS down, and this improves
the handling of the TFCCS during bonding, assembly and test (BAT).

      The distance piece made out of silicon rubber or springs
allows, due to its flexibility, an adequate thermal j...