Choose by pad function
Solder pads, contact fingers and wire-bonding surfaces have different needs. ENIG, ENEPIG, OSP and electrolytic gold constructions are not interchangeable. Confirm the process, compatibility and acceptance criteria for the actual application.
ENIG and hard gold serve different roles
ENIG uses an electroless nickel layer with immersion gold and is commonly selected for solderable surfaces. Electrolytic hard gold is often considered for wear-contact applications. Specifying only ‘gold finish’ leaves the construction and purpose ambiguous.
Write a measurable finish specification
State the finish system, thickness units, measurement locations and applicable acceptance document. The conversion is exact: 1 microinch equals 0.0254 micrometres. A unit conversion does not establish whether a thickness is suitable or compliant.
Use the converter, then review the requirement
The engineering tools page converts microinches and micrometres without recommending a plating target. Submit the pad purpose, mating cycle requirement and assembly process for a finish review.