It was created to address the growing need for a standardized ENIG process that ensures:

June 2025. Specification for Electroless Nickel/Electroless Palladium Immersion Gold (ENEPIG) Plating for Printed Boards. Accuris Standards Store

: Compatible with both leaded and lead-free (SAC305) reflow cycles.

Published by the IPC (Association Connecting Electronics Industries), is titled "Specification for Electroless Nickel/Electroless Palladium/Immersion Gold (ENEPIG) Plating for Printed Boards."

The IPC‑4556 PDF is a and must be purchased from authorized sources. Free downloads from unauthorized websites are illegal and may contain outdated, incomplete, or incorrect versions of the standard.

Using the specification to audit and select PCB suppliers.

The best source for the most up-to-date, authorized PDF copy.