Overview
IEC 61191-2:2017 - "Printed board assemblies - Part 2: Sectional specification - Requirements for surface mount soldered assemblies" - defines requirements and acceptance criteria for surface mount (SMT) soldered connections on printed board assemblies. It applies to assemblies that are entirely surface mounted and to surface-mount portions of mixed-technology assemblies (e.g., through‑hole, chip mounting, terminal mounting). This third edition (2017), including the September 2019 corrigendum, updates terminology, corrects IEC references, adds five termination styles, and aligns acceptance criteria with IPC‑A‑610F.
Key topics and technical requirements
- General requirements and process control: alignment, placement tolerances, and process monitoring for reliable SMT assembly.
- Component mounting and lead formation: rules for gull‑wing, J‑lead, flat ribbon, coined/rounded leads, P‑style, castellation and other terminations.
- Solder joint acceptance: criteria for fillet height, heel and toe fillets, wetting, dewetting, leaching, voids, pits, solder wicking, bridging and solder spikes.
- Package families covered: guidance for BGAs (collapsing and non‑collapsing balls), column grid arrays, leadless chip carriers, MELFs (cylindrical end‑cap devices) and bottom‑terminated components (including D‑Pak style thermal planes).
- Post‑soldering conditions: inspection criteria for component tilt, marking degradation, disturbed joints, open circuits and non‑wetting.
- Rework and repair: allowable defects and corrective actions; Table of reworkable defects included.
- Placement requirements (Annex A): normative details on component positioning, overhang limits, lead height prior to soldering, and castellated carrier registration.
Practical applications
IEC 61191-2:2017 is used to:
- Establish in-house acceptance criteria and inspection checklists for SMT production lines.
- Define quality gates for incoming and outgoing inspection in contract manufacturing.
- Support process development for soldering, reflow profiling and automated optical inspection (AOI) rule‑sets.
- Guide failure analysis, repair and rework decision-making to distinguish reworkable vs. non‑reworkable defects.
Who should use this standard
- PCB assembly engineers and process engineers
- Quality managers and production supervisors in electronics manufacturing
- Contract manufacturers, OEMs and CMs implementing SMT production controls
- Inspectors, test engineers and standards compliance auditors
Related standards
- IPC‑A‑610F (acceptance criteria alignment)
- Other parts of the IEC 61191 series and referenced IEC standards (corrected in this edition)
Using IEC 61191-2:2017 helps manufacturers ensure consistent, industry‑recognized acceptance and inspection of SMT solder joints, improving reliability and reducing rework in electronic assemblies.