As electronic devices continue to shrink while demand for reliability grows, the transition from traditional rigid boards to Rigid-Flex assemblies has become a critical skill for designers and engineers. However, navigating the complexities of merging rigid materials with flexible films is no small task.
Released in late 2020 by IPC, IPC-7093A, Design and Assembly Process Implementation for Bottom Termination Components, is an update to the original IPC-7093 standard. It specifically addresses the challenges of BTCs, which are surface-mount components where the terminations are located on the underside of the package (e.g., QFN, DFN, and LGA packages).
Myth 2: “AOI can replace x-ray.”
Truth: Automated Optical Inspection (AOI) only sees the peripheral edge of a BTC. The ipc-7093a pdf explicitly states that AOI alone is insufficient for Class 3 assemblies.
standard is a comprehensive overhaul of the original IPC-7093, specifically focusing on the design and assembly process implementation for Bottom Termination Components (BTCs) like QFN, DFN, and LGA packages I-Connect007 Key Features of IPC-7093A BTC-Specific Guidance
Voiding Control: Gases trapped in the large thermal pad during reflow can create "voids" (holes), which are only detectable via X-ray and can impact performance. Key Updates in the Revision A "PDF"