Decide the scope of identification
Determine whether traceability is needed by lot, panel, assembly, or individual circuit. Consider the product’s investigation and service needs rather than asking for maximum records without a purpose. Connect identifiers to the released part revision. Define any marking location with regard to available space, insulation, terminal cleanliness, and the mechanical duty of the region.
Traceability chain
| Investigation item | Question | Evidence to retain |
|---|---|---|
| Design | Which approved definition produced the part? | Board and assembly revisions |
| Material | Which specified and accepted materials were used? | Lot-linked supplier and substitution records |
| Process | What relevant build or repair history applies? | Controlled manufacturing records |
| Acceptance | Which results cover the delivered item? | Inspection, test and disposition linkage |
Link materials and processes to results
Identify the laminate, coverlay, reinforcement, adhesives, finishes, and populated components whose records matter to the agreed scope. Include accepted substitutions and relevant process or rework history. Use the inspection plan to tie measurements and test reports to those identifiers. A certificate without a clear relationship to the delivered lot may be difficult to use during an investigation.
Agree retrieval and change handling
State who retains records, how long the contract requires retention, and what can be supplied with the shipment or on request. Define how mixed lots, replacement parts, and deviations are documented. Trial the traceability chain on a sample record before routine production: start from a delivered identifier and check whether the relevant construction and acceptance evidence can actually be found.
Before you release the design
- Specify identification granularity before panel and marking design.
- Keep approved material substitutions traceable.
- Agree report availability and retention with the supplier.
- Check the chain using an actual representative delivered identifier.
Watch points
- A date code alone may not identify the exact material or design revision.
Practical questions
Does every small flex need a printed serial number?
Not necessarily. Choose a traceability method suited to the circuit and product. Packaging, panel position, assembly identifiers, or other controlled records may form the agreed chain.
Can traceability be added after a failure occurs?
You can recover existing records, but missing material or process links cannot always be reconstructed. Define and exercise the needed record system before the build.
Technical references
References support the material or design context. Check the exact grade, part number, document revision and project conditions before release.Updated 27 September 2026 · Technical content policy · Engineering guidance supports project review; the agreed drawing defines the build.