Controlled-Impedance 4-Layer + Heavy-Copper PCBA to IPC Class 3

An ISO 9001-certified OEM needed prototype and short-run boards — a 4-layer design with a non-standard controlled-impedance stackup and a heavier-copper 2-layer production board — all delivered with Certificate of Compliance documentation.

The 4-layer board required an exact non-standard layup with tight 100 Ω differential-impedance control; the customer asked us not to quote unless the custom stackup could be respected exactly. Both boards needed CoC documentation at IPC Class 3.

We confirmed our custom-stackup and impedance-control capability, worked through the customer's engineering questions on edge plating and surface finish, committed to the Certificate of Compliance, and quoted both the 4-layer custom boards and a short 3 oz-copper ENIG 2-layer production run.

The customer accepted and paid for the 2-layer production run; the 4-layer controlled-impedance boards proceeded to quotation with engineering questions resolved in dialogue.