Reply to:   RE>>FWD>RE>ASSY revision J-STD-

Jeff,

The concern I would have about soldering directly to a chip components
electrical terminal is the bond strength of the electrical termination to the
ceramic.  In my experience, I've observed quite a variation in bond strength
(tensile and clevage forces) between the metallizations and ceramic.  If the
stress/strains can be eliminated/controlled, then I don't see any reason not
to do a direct component attach to a suitable area on the surface of the
printed board.

I wouldn't recommend doing the component attach to a solder resist over
conductors because (IMO) solder resist shouldn't be used as a primary
dielectric --- too many process variables.

IMO, it can/could be done --- go for it.
Ralph

--------------------------------------
Date: 7/18/96 9:11 AM
To: Ralph Hersey
From: [log in to unmask]
Ralph,
Your modification illustration assumes surface copper lands from which the
addedcomponent must be isolated.  For small chip components and a little bit
of open real estate, what are your thoughts on bonding the component directly
to the
"main" pwb and then soldering the jumper wires to the component terminations?

Jeff

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