Sourcing PCBA: RFQ, Sample Controls and Import Handover

PCBA sourcing is not a component purchase. You are buying a manufacturing service applied to a board, and the quotation only becomes meaningful once the process window, test coverage and handover points are stated. The following focuses on the request for quotation, sample-to-order controls, packing and document handover, delivery responsibility and import preparation.

What the RFQ must contain

Send Gerber or ODB++ data, the bill of materials with manufacturer part numbers and acceptable alternates, the assembly drawing, and a clear statement of which side is populated. State the board finish, layer count, material, thickness and panelisation preference. Specify the solder alloy and whether lead-free processing is required. For mixed technology, say which through-hole parts are hand-soldered and which are wave- or selective-soldered. If the design includes fine-pitch or BGA devices, say so, because that changes stencil, reflow profile and inspection needs. Ask the supplier to confirm which BOM lines they will source, which they will not, and how they handle obsolete or long-lead items. A quotation that does not separate bare-board cost, component cost, assembly labour, tooling, test and packing is hard to compare with another.

Process, test and acceptance

Agree on the inspection standard before production, not after. Typical acceptance language covers solder joint quality, placement accuracy, polarity, cleanliness and marking. State whether you require automated optical inspection, X-ray for hidden joints, in-circuit test, functional test or a combination. If functional test is required, define who supplies the fixture and the test programme. Ask for first-article approval with photographs and measurement records. Where the board carries firmware, state whether programming and version control are part of the order.

Sample-to-order controls

Treat the sample as a controlled reference. Record the sample serial or date code, the revision of Gerber and BOM used, and the firmware version if applicable. Keep the approved sample and the signed specification at your end as well as the supplier's. Before mass production, confirm that the production BOM and Gerber revision match the approved sample. Ask how engineering changes are raised and who signs them off. If the supplier proposes a substitute component, require the datasheet, the reason for substitution and written approval before it is fitted.

Packing, documents and delivery responsibility

PCBA is moisture- and static-sensitive. State the required packing: anti-static bagging, desiccant, humidity indicator, board separators, and carton stacking limits. Ask for the packing list format and whether carton labels carry part number, revision, quantity and date code. Agree which documents travel with the shipment: packing list, invoice, and any test or conformity records the supplier can actually provide. When the supplier claims a certification or test report, ask for the document and check that its scope matches your board; do not assume a general certificate covers your assembly. Settle the trade term explicitly and write down where risk passes: at the supplier's dock, at origin port, or at destination. State who books freight, who arranges insurance, and who handles customs formalities at each end.

Hypothetical scenario

A buyer needs 2,000 controller boards with a mix of 0402 passives, one QFN and a handful of through-hole connectors. The first quotation looks low, but it excludes stencil tooling, X-ray and functional test. A second supplier quotes higher with tooling and test included and names the BOM lines it will not source. The buyer requests a sample built to the production revision, approves it against a written specification, and requires the same revision for the order. At packing stage the buyer asks for anti-static bagging with humidity indicator and a packing list keyed to date code. The trade term is agreed as FOB, so the buyer books freight and insurance and confirms with the import broker which documents are needed. The higher quote turns out to be the more comparable one because it prices the same scope.

Import-preparation questions

Confirm the correct commodity description with your broker rather than relying on the supplier's label. Ask what origin the supplier will declare and on what basis. Check whether the shipment needs any specific handling, and confirm the incoterm with your forwarder before the order is placed. Keep the approved sample, specification and revision records together so that an incoming inspection has something to compare against.

Actionable checklist

- Issue a written RFQ with Gerber, BOM, assembly drawing and process requirements.
- Require a cost breakdown by board, components, assembly, tooling, test and packing.
- Fix the inspection standard, test coverage and first-article approval in writing.
- Control the sample: serial, revision, firmware and signed specification.
- Approve any substitute component in writing before fitting.
- Specify anti-static and moisture-controlled packing and the packing list format.
- Agree the trade term, risk transfer point, freight, insurance and customs responsibilities.
- Confirm commodity description and origin declaration with your import broker.
- Involve a qualified electronics or compliance specialist where the board's end use requires it.