In-Circuit Testing for Production PCB Assemblies

Start with the circuit features and assembly faults that matter to the product. Opens, shorts, passive-value checks and selected device tests need suitable access and measurement conditions. A statement that a board receives ICT is useful only when the program scope and exclusions are also known.

Provide the controlled BOM, schematic and layout data with product variants identified as part of the PCB assembly release package. Ask for a review of component tolerances, parallel paths and inaccessible nodes. A percentage based on contacted nets cannot be treated as a measured percentage of all possible defects detected.

The test program depends on the electrical connections that the fixture can reliably make. Board support, contact locations, component clearance, alignment and the tester interface belong in one coordinated review. Confirm the actual platform and proposed capabilities for your order.

Program debug should distinguish a board fault from a contact, data or test-condition problem. Agree reference material and validation checks before release. Changes to limits, fixture wiring or program logic need controlled revision records so subsequent results remain interpretable.

Specify unit identity, board/BOM revision, program revision, measured parameter, result, limits and disposition where applicable. Failed records should make the location and measurement clear enough to guide investigation. Keep first-run and repeated results distinguishable.

A unit that passes after reseating or rerunning should not erase the initial observation. Define retry rules and when a test engineer must review the result. For a production issue, compare the product evidence with fixture maintenance and station checks before changing acceptance criteria.

Use the station-time tool with measured test and handling assumptions to discuss batch capacity. Include setup and additional executions explicitly. It models one sequential station and does not calculate the time needed for program development, diagnosis, repairs or production queues.

Review ICT alongside optical inspection, X-ray and functional testing according to the product requirements. Some platforms can combine functions, but the proposed configuration must be stated. For repeat contract manufacturing, send PCBSync the intended build quantity, forecast and required report to obtain a scope-specific quotation.