IPC-4556 - Revision A - Global Electronics Association: Store
Deposited on top of the nickel layer. This acts as an anti-oxidation barrier, protecting the nickel from corroding during the subsequent gold immersion process.
The palladium layer acts as a barrier that prevents the aggressive immersion gold process from corroding the underlying nickel, a common failure point in standard ENIG finishes. ipc4556 pdf
The initial release established standard boundaries for ENEPIG processing. However, the 2016 Amendment 1 introduced an absolute cap of 0.070
More information on how IPC-4556 compares to IPC-4552 (ENIG). IPC-4556 - Revision A - Global Electronics Association:
ENEPIG is a multifunctional, three-layer surface finish plated over a copper base metal. Its primary components are:
The IPC-4556 PDF is a highly sought-after document in the electronics industry, particularly among manufacturers, assemblers, and quality control specialists. This document provides critical information on the "Requirements for Soldering of Printed Boards" and is an essential resource for ensuring the reliability and quality of electronic assemblies. Its primary components are: The IPC-4556 PDF is
The standard specifies the required thickness for each layer of the ENEPIG finish, which is critical for ensuring both performance and cost-effectiveness:
The addition of palladium provides a more robust shield against environmental corrosion compared to traditional finishes like immersion silver or tin. Quality Assurance and Testing