A PCB fails final test. Why? Was it the solder paste? The screen printer? The PCB assembly machine? The reflow oven or none of the above? Unplanned downtime is a costly fact of life. In order to minimize the length of downtime it is necessary to have clear details on exactly what the source of the problem is, not just the symptoms. This information allows operators and maintenance personnel to go directly to take corrective steps more quickly and minimize downtime. There are many machines and materials involved in the assembly of a complete PCB; screen printers, conveyors, pick and place systems, reflow ovens, Automated Optical Inspection (AOI), solder paste and components. Some of this equipment has the ability to check its results before, during or immediately after it has completed its task. Until now there have been few real-time tools for the pick and place systems. In many cases, high speed movement on these machines makes it extremely hard to "see" exactly what is happening. Components misplaced by the assembly system could be caused by many different factors. Without tools to provide a clear view of very high speed placement, it is difficult to the cause of misplacement. How much easier would this task be if operators and maintenance personnel are armed with detailed information on the nozzles, feeders, and actual images of the picking and placing of parts on the PCB? This paper will discuss tools available for the placement machine to assist in root cause failure analysis (RCFA).
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