Hi Werner,

Are you referring to the differing thermal coefficients contributing to
unreliability?

-----Original Message-----
From: Werner Engelmaier [mailto:[log in to unmask]]
Sent: Thursday, August 26, 1999 6:02 AM
To: [log in to unmask]
Subject: Re: [TN] Advice on solder pad design


Hi Eric,
Get a copy of IPC-SM-782.
But why are you considering LCCs (leadless ceramic chip carriers)? Are you
mounting them on ceramic? If you are using FR-4 or any other polymer-based
substrates you can forget about reliabilty in any environment other then a
really benign one, such as sub-ocean cable repeaters. You could of course
put
solder columns on the component.

Werner Engelmaier
Engelmaier Associates, L.C.
Electronic Packaging, Interconnection and Reliability Consulting
7 Jasmine Run
Ormond Beach, FL  32174  USA
Phone: 904-437-8747, Fax: 904-437-8737
E-mail: [log in to unmask], Website: www.engelmaier.com

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