Of equal concern for minor excessive temperatures, is that the bond strength of the copper on the PWB will be the first thing affected. The copper may pull away from the laminate due to thermal stresses and eventually result in high impedance connections. Such poor electrical connections could lead to the laminate decomposition mentioned by Bob DB or reduced clearances in a tight space.
Regards, Peter L. Tarver Nortel [email protected] >---------- >From: DenBleyker, R. (919-543-7251 TL 441)[SMTP:[email protected]] >Sent: Tuesday, September 16, 1997 4:41 AM > >In my opinion, the designer is responsible for the PC board temperature as >well as the semiconductor. The PC board is both a structural element of the >product maintaining creepage/clearance distances, and an insulator. PC board >failure can easily result in a safety problem. Overtemperature will lead to >decomposition of the epoxy binder and board faiure. > >Bobdb at vnet.ibm.com > >
