SMT007 Magazine


Issue link:

Contents of this Issue


Page 42 of 80

November 2014 • SMT Magazine 43 patterns. Both of these methods are employed when the physical dimensions or mounting hole patterns need to be changed on a PCB. conclusion There are a variety of PCB fixes which may need be made to the physical PCB due to errors in the board layout, part changes or PCB board fab errors. There are a variety of options avail- able, including but not limited to board respins, scrapping of the boards, and reworking the boards, whether they are already populated or not. The most common fixes to these errors in- clude cutting of the conductors, selective solder mask removal, addition of traces and pads or mechanical routing or drilling of holes. A vari- ety of proven industry methods, depending on the type of fix required, are available to make these adjustments. smt references 1. IPC-7711/7721 "Rework, Modification and Repair of Electronic Assemblies," Revision B. 2. "Lead-Free PTH Rework Process Challeng- es and Solutions for a Complex Server PCBA," Willie Davis, PK Pu, Wang Yong Kang, Alex Chen, Da, SMTAI July 2010. 3. "Laser – A flexible tool for PCB and device rework," Wettermann, Robert. SMTAI August 2008. 4. "PCB Pad Site Dress Methods on BGA and Socket Pad Arrays," James Wade and Raiyo Aspandiar; Don Naugler and Terry Leahy, IPC APEX EXPO 2010. Bob Wettermann is the quality manager of beST inc. and an MiT. he is the author of numer- ous articles and has presented at a variety of SMTa, aSQC, ipC and other international confer- ences on the topic of PCB rework, repair and assembly. CliCk To View Video Interview Tim Jensen, senior product manager with indium, discusses some of the newer lead-free solder alternatives that are suitable for high-temperature (and low-temperature) applications. alternative methodologies for High-temp bonds by Real Time with... SMTAI 2014 feaTure bare boarD ecos, ecns anD Design moDiFications continues

Articles in this issue

Links on this page

Archives of this issue

view archives of SMT007 Magazine - SMT-Nov2014