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MIDI-Master Homepage - by A.S. Software
MIDI-Master Homepage - by A.S. Software
However, specifying ENIG on your fabrication drawing is only the first step. To ensure that your boards meet rigorous quality standards, you need the definitive industry guideline: .
: Unlike standard ENIG (Electroless Nickel Immersion Gold), IPC-4556 focuses on the addition of the Palladium layer, which prevents the "black pad" defect and makes the board suitable for high-reliability military and medical applications. Where to Access the Document ipc-4556 pdf
A medical device manufacturer ordered ENIG boards but did not specify IPC-4556. The fabricator used a low-phosphorus nickel bath (5% P) to save costs. During assembly, multiple BGAs exhibited intermittent connections. Cross-sectioning revealed a "black pad"—a brittle, hyper-corrosive nickel layer that fractured under solder ball stress. The entire batch (500 boards) was scrapped. IPC-4556 would have prevented this by mandating 7-11% phosphorus. However, specifying ENIG on your fabrication drawing is