ENIG or lead-free HASL: how to choose a surface finish
Pad geometry, how the board is assembled, and where it will live — the inputs that pick a finish.
Start from the constraints that are actually fixed
Pad geometry, how the board is assembled, and where it will live — the inputs that pick a finish.
Board size, assembly method, and delivery terms differ on every job. Write the constraints down before debating options, so engineering and purchasing are looking at the same problem.
Put the review pack in one place
Use the latest design files, and mark the revision, the requirements that are settled, and the questions that are still open. If a note can be read two ways, add a sentence or a callout. Do not rely on the file name.
Keep supplier and factory feedback in that same pack, and check that every change landed in every file you will send.
Leave a record of what was agreed
After the review, keep the revision and the items that were confirmed. Before the next edit or a production release, check that those agreements still hold.
This article is sample copy for the layout. Process requirements for a real build come from that project's review, not from this page.
Sample copy for the layout. This is not a published guide and it is not a process specification.
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