The intent of IPC/PERM-2901 design guide is to assist design engineers in developing electronics that are completely Pb-free and meet the demanding requirements of Aerospace, Defense and High Performance (ADHP) systems and products.

IPC/PERM-2901, Pb-free Design and Assembly Implementation Guide

Coverage is given to Pb-free solders and solder joints, tin whiskers, printed board defects, product qualification, supply chain management, obsolescence management, and COTS assembly, selection and use.

1.2 SCOPE
1.2.1 The intent of this design guide is to assist design engineers in developing electronics that are completely Pb-free and meet the demanding requirements of ADHP systems and products. (For the present time, wiring/cabling is not included in the scope.) It is assumed that the design engineers using this guide are competent and experienced with SnPb based electronics but may not be fully conversant with the detailed vagaries of Pb-free materials, components or manufacturing processes or how these impact equipment reliability and longevity.
a. This guide has been generated to address those ‘delta’ differences between SnPb and Pb-free solder technologies. Information/guidance that pertain to both technologies are not necessarily included. Any redundant information may be the result of completion or context.
b. The “delta” differences are generally categorized as described in GEIA-HB-0005-3 as follows:
i) Typically poorer wetting ability
ii) Differences in appearance and inspection criteria
iii)Typically higher melting temperature
iv) Potential tighter process window for repair/rework

Preview the IPC/PERM-2901 table of contents .pdf file