Browse Prior Art Database

Cable Flat PAC Connector with Two-Piece Metal Faraday Cage and Latches Via Transfer Molding

IP.com Disclosure Number: IPCOM000115379D
Original Publication Date: 1995-Apr-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 4 page(s) / 137K

Publishing Venue

IBM

Related People

Crosby, EG: AUTHOR [+5]

Abstract

Disclosed is an improved design and construction technique for the flat pac high speed signal connector (commonly referred to as the Harcon connector system) used to distribute data and/or clock signals internal to the computer. The improvements focus on RF shielding and ESD tolerance of the connector/cable assembly, while introducing reliability and manufacturability enhancements due to the disclosed unique design implementation of a "Faraday Cage" which is an internal overmolded structure that shields the terminations of the high speed cable to printed circuit card inside of the connector. Metal latches provide improved connector retention in the Harcon Grouper (which is metallized to provide frame ground path, and a reliable path to frame ground for the shielding by being an integral part of the Faraday Cage.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 40% of the total text.

Cable Flat PAC Connector with Two-Piece Metal Faraday Cage and Latches
Via Transfer Molding

      Disclosed is an improved design and construction technique for
the flat pac high speed signal connector (commonly referred to as the
Harcon connector system) used to distribute data and/or clock signals
internal to the computer.  The improvements focus on RF shielding and
ESD tolerance of the connector/cable assembly, while introducing
reliability and manufacturability enhancements due to the disclosed
unique design implementation of a "Faraday Cage" which is an internal
overmolded structure that shields the terminations of the high speed
cable to printed circuit card inside of the connector.  Metal latches
provide improved connector retention in the Harcon Grouper (which is
metallized to provide frame ground path, and a reliable path to frame
ground for the shielding by being an integral part of the Faraday
Cage.  ESD tolerance is improved by utilizing static dissipative high
speed cable and by providing a means to ground the static dissipative
jacket to the Faraday Cage.  Transfer molding is employed as a
manufacturability gain to encapsulate the cage shield connector
assembly and provide structural integrity of the cable assembly, as
opposed to ultrasonic bonding of thin plastic housings or attempted
injection overmolding of fragile cable/pcb subassemblies.

      Higher performance processors require improved RF shielding and
noise immunity design of signal cables, logic and clock, among other
requirements.  A related concern is ESD tolerance of the signal
system (e.g., to enable concurrent maintenance activities that
involve unplugging and plugging of cables with power to the boards)
which can be improved by the use of a static dissipative cable jacket
with proper frame grounding.  A recently established technique and
strategy is to incorporate metal plating onto the two plastic housing
halves of the current cable flat pac connector, which when assembled
sandwich the terminated cables (and PC card) within a "Faraday Cage"
shield.  A Faraday Cage can be defined as a 360 degree   metal
enclosure surrounding the open wire areas of the cable connector
terminations.  In order for this design to optimally work
electronically, the following ground-rules are required:
  1.  Use of high resistance static dissipative "black" jacket or use
       of an electrically isolated braided wire shield.  The "black"
       high speed trilead design (logic cable) satisfies the former;
and
       the "black" triaxial design (clock cable) satisfies the
latter.
  2.  Electrical termination of the static dissipative jacket and/or
       the braided wire shield to the platings.
  3.  Grounding of the metallized platings to frame ground.  This is
       easily accomplished in conjunction with the use of plated
       super-groupers (which package the plated cable flat pac
       connectors) which in...