Hi Van

Per IPC 610C page A-1
Electrical Clearance  
The minimum spacing between conductors between conductive patterns, layer to layer conductive spaces ( z axis ) and between conductive materials ( such as conductive markings or mounting hardware )  and conductors shall be in accordance with Table 6-1.
If needed let me know and I'll fax it to you.

Again from 610c page 6-23
Entrapped / encapsulated / attached is intended to mean normal service environment of the product will not cause a solder ball to become dislodged.
Testing would be a customer standard.
As: vibration, reliability. shipping................ so on so on.
Please remember the words
entrap and encapsulate and what they  mean.
Hope this helped
There's  my two cents again
Nancy T




>>> Van Hoang Dinh <[log in to unmask]> 03/20/00 04:16PM >>>
Good morning all,

1.Anyone known where can I look for a definition of ELECTRICAL DESIGN CLEARANCE ?

2.How we define or experiment test to prove that the solder balls are entrapped and not cause a solder ball to become dislodged?

THANKS ALL

VAN 

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