Specify more than a material family
A family name such as FR-4 does not identify a single laminate grade. State the required manufacturer and grade when fixed by the design. If alternatives are acceptable, identify the properties that must be preserved and who approves a substitution.
Connect electrical and mechanical requirements
List finished board thickness, intended layer structure, impedance requirements and the operating conditions that affect the selection. For transmission lines, specify the construction and frequency assumptions used by your design team rather than treating a single dielectric value as universally applicable.
Review the assembly thermal profile
Provide relevant component and board handling constraints. Laminate selection, storage and the intended assembly sequence should be reviewed together. Material availability and suitability must be confirmed for the actual fabrication package.
Record approved substitutions
If a proposed material changes stackup dimensions or electrical assumptions, resolve the change before fabrication. Release the approved drawing and stackup with a consistent revision; keep the approval with the manufacturing records.
Project review checklist
| Item | What to include |
|---|---|
| Source documents | Use the current design revision and approved part data |
| Consistency check | Resolve conflicting values before release |
| Manufacturing review | Submit remaining questions with the quotation request |