IPC-4671 and IPC-7351B法規 問題請教

hlperng

IPC 4761_2006, Design Guide for Protection of Printed Board Via Structures

May be seen at Website: https://docs.google.com/viewer?url=http%3A%2F%2Fhitech.com.mk%2FResources%2FDocuments%2FIPC-4761.pdf
3.4 Long-Term Reliabiity Concern
Single-sided via protection (Types I-1, II-a, and III-a) should not be used with bare copper hole walls.  Any attempt to apply a surface finish to a hole wall that is not protected by the plug maerial resulting from a partial penetration into the via will result in a bare copper area at the plug material/hole barrel interface. This bare copper area will be attacked by any chemicals entrapped within the hole during board fabrication, as well as those trapped during assembly process (the partial plug process may have gaps between the plug material and the hole wall allowing entrapment of chemicals).  The resulting contamination can combine with moisture and corrode the thickness of the hole wall plating to a degree where the plating is no longer able to withstand the stresses of operating temperature common in assembly processes as shown in Figure 3-5.  Final finishes should be applied prior to pluging.

IPC-7351B_2010, Generic Requirements for Surface Mount Design and Land Pattern Standard
TOC see at Website: https://docs.google.com/viewer?url=http%3A%2F%2Fwww.hytekaalborg.dk%2Ffiles%2Findholdsfortegnelser%2FIPC-7351B.pdf

IPC-7351_2005, Generic Requirements for Surface Mount Design and Land Pattern Standard
See at Website: http://pcbget.ru/Files/Standarts/IPC_7351.pdf