PCB electronic assembly joins components to a manufactured board according to a released design. It can be used for prototypes as well as production; a fully validated product is not a prerequisite for every development assembly. The important requirement is that the build’s purpose and configuration are clear.
Inspect the material package
Check the exact component identities, quantities and packaging against the approved BOM. Preserve labels needed for traceability. Separate unavailable or disputed parts from material already approved for the build so a purchasing question does not become an undocumented substitution.
Identify components with special handling requirements early. Their requirements may affect storage, the order of assembly or which cleaning and coating operations are permissible.
Use component-specific handling instructions
Texas Instruments’ humidity-sensor guidance provides a useful example: an exposed sensing element can require protection from contaminants, and some package variants include a removable protective cover. This means a generic board-wash instruction is not appropriate for every component.
Review the documentation for the actual order code. Do not transfer an instruction from another sensor, package or material without checking its relevance. Where multiple suppliers’ requirements interact, have the assembler resolve the process before production.
Build a handling map
| Component concern | Process question |
|---|---|
| Moisture sensitivity | What storage and exposure records are required? |
| Exposed sensing surface | Which materials or operations must be kept away? |
| Mechanical sensitivity | How will the part be supported and handled? |
| Programming | When and how is the intended software loaded? |
| Protection after assembly | Which areas may be coated or encapsulated? |
Connect handling to the assembly sequence
Agree when sensitive components are installed and when protective materials are removed. Identify inspections needed before an area becomes hidden or inaccessible. Record these decisions in the work instructions rather than relying on an operator’s memory.
Check the fitted configuration before soldering where the process permits. Resolve orientation and part identity questions before continuing to a step that makes correction more difficult.
Preserve the evaluated configuration
Record rework, component replacements and accepted deviations. A prototype’s test results should be connected to the assembly that actually underwent evaluation. Otherwise, a handling-related issue can be mistaken for a design problem or vice versa.
For repeat production, carry accepted improvements into the controlled release and handling instructions. The goal is a reproducible process appropriate to the actual component set. Include handling notes when introducing an approved replacement part.
Primary reference: Texas Instruments humidity-sensor handling considerations. See the assembly documentation guide.
Move from reading to a build-ready project
Use the fabrication and assembly checklists to prepare drawings, production files and test requirements.
Open the DFM checklist