Issue link: https://iconnect007.uberflip.com/i/1535183
MAY 2025 I DESIGN007 MAGAZINE 23 • Board details regarding layer stackup, thickness, copper weights, process- ing conditions, design con- cepts, and drill hole tables (TH and HDI details) • Tolerances (IPC Class), surface finish specifications, testing requirements, mark- ings, thieving if allowed, assembly multi-up array, and handling requirements • Component type, placement locations, and orientation indicators, polarity, refer- ence designators, special mounting and installation instructions, automated test equipment, electrical testing requirements, and fixtures • Workmanship specifications, conformal coating if required, cleanliness requirements, mechanical hardware, hard- ware torquing requirements, solder joint specifications, labeling, and soldering to include solder paste It's very important that the IPC class designations (e.g., Class 2 or Class 3) should be clearly noted to set expectations for inspection and quality levels. e IPC Standards Tree (Figure 1) is an excellent reference for identifying what IPC standard applies to what stage throughout the build process. Comprehensive Bill of Materials (BOM) A BOM should go beyond a list of parts. It must be supply-chain-aware, factoring in part availability, lifecycle status, and potential obso- lescence, and alternates. By integrating supply chain intelligence during the design phase at the point of design, known as design for sup- ply chain resilience, engineers can avoid costly late-stage redesigns or board respins. 3D CAD Models and Prototypes 3D models and prototypes support both vir- tual (aka digital twin) and physical validation of the design. With the rise of model-based systems engineering, using digital twins and simulation to ensure component fit, mechani- cal integration, and thermal management is becoming an industry standard. ® IPC STANDARDS — EVERYTHING YOU NEED FROM START TO FINISH End-Product Acceptability of Printed Boards IPC-A-600 Qualifications for Printed Boards IPC-6011, 6012, 6013, 6017, 6018 Base Materials for Printed Boards IPC-4101, 4103, 4104, 4202, 4203, & 4204 Design & Land Patterns IPC-2221, 2222, 2223, 2226 & 2228 + 7352 Repair IPC-7711/21 SMT Reliability IPC-9701–IPC-9704 IPC-9706–IPC-9709 Requirements for Soldered Electronic Assemblies IPC J-STD-001, IPC-HDBK-001, IPC-AJ-820 Acceptability of Electronic Assemblies IPC-A-610 Requirements and Acceptance for Cable and Wire Harness Assemblies IPC/WHMA-A-620, IPC-D-620, IPC-HDBK-620 Learn about IPC standards at www.ipc.org/standards Data Transfer and Electronic Product Documentation IPC-2581 Series, IPC-2610 Series Copper Foils IPC-4562 IPC Terms and Definitions IPC-T-50, IPC-T-51 Solder Mask IPC-SM-840 Assembly Materials IPC J-STD-004 IPC J-STD-005 IPC-HDBK-005 IPC J-STD-006 IPC-SM-817 IPC-CC-830 HDBK-830 HDBK-850 Stencil Design Guidelines IPC-7525 IPC-7526 IPC-7527 Solderability IPC J-STD-002 IPC J-STD-003 Acceptability Standard for Manufacture, Inspection, & Testing of Electronic Enclosures I IPC-A-630, IPC-HDBK-630 June 2023 Materials Declaration IPC-1751 IPC-1752 IPC-1755 Surface Finishes IPC-4552 IPC-4553 IPC-4554 IPC-4555 Electrical Test IPC-9252 Test Methods IPC-TM-650 IPC-9241 IPC-9631 IPC-9691 High Speed/ Frequency IPC-2141 IPC-2251 Advanced Packaging IPC J-STD-030 IPC-7091 IPC-7092 IPC-7093 IPC-7094 IPC-7095 Storage & Handling IPC J-STD-020 IPC J-STD-033 IPC J-STD-075 IPC-1602 IPC-4556 from Start to Finish 18 Figure 1: IPC standards contain all the information you need, from start to finish. (Source: IPC Checklist for Producing Printed Board Assemblies)