5. Electrical Test: ICT, FCT, boundary scan
A visually perfect solder joint is insufficient if the circuit malfunctions. Electrical testing serves as a mandatory verification point before an assembly leaves the PCBA line.
This chapter details distinct roles of In-Circuit Testing, Functional Testing, and Boundary Scan methodologies. Strategic deployment isolates faults to the component level, supporting production flow without creating bottlenecks.
- 5.1 Strategy & Coverage
When designing a manufacturing process, electrical test serves not just as a final checklist item, but as an essential technical and quality safeguard. A well-planned test strategy achieves two primary goals: it provides high Defect Coverage (support...
- 5.2 ICT & Fixture Design
In-Circuit Test (ICT) is a fast and cost-effective method capable of identifying a large majority of common structural defects—such as opens, shorts, and incorrect component values—in high-volume production. The success of an ICT strategy, however, b...
- 5.3 Boundary Scan Essentials: JTAG
As component packaging has evolved from traditional through-hole pins to high-density Ball Grid Arrays (BGAs) and Chip-Scale Packages (CSPs), physical solder joints are increasingly hidden beneath the component bodies. This physical reality makes tra...
- 5.4 Functional Test Design
Functional Test (FCT) is the final safeguard before a product leaves the manufacturing facility. While In-Circuit Testing (ICT) and Boundary Scan excel at finding structural issues—confirming that components are present and correctly soldered—they ca...
- 5.5 Data Logging & Repair Tickets
In a high-volume manufacturing environment, conducting tests is only part of the process; managing the data those tests generate is equally important. A test station that simply flashes a green "PASS" or a red "FAIL" light does not provide enough ins...