Searching for an typically means you need the official document for one of the following reasons:
This article is for informational purposes only and does not replace the official IPC-4556 document. Always refer to the latest standard for legally binding requirements. ipc4556 pdf
If your application involves very fine-pitch (below 0.3mm) or multiple reflow cycles, ENIG per IPC-4556 remains the gold standard—literally. Searching for an typically means you need the
In the high-stakes world of printed circuit board (PCB) manufacturing, surface finish is not merely an aesthetic choice—it is a critical determinant of solderability, reliability, and shelf life. Among the many standards governing these finishes, stands out as the definitive specification for Electroless Nickel / Immersion Gold (ENIG) . In the high-stakes world of printed circuit board
The IPC-4556 standard explicitly mandates that layer thickness be measured using X-Ray Fluorescence (XRF) methodology . During the standard's development, IPC used XRF extensively, establishing a detailed set of measurement criteria. XRF is the only IPC-approved non-destructive technique for this purpose. Key considerations for accurate XRF measurement include: