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90 SMT007 MAGAZINE I JULY 2018 requires having the product's chemical compo- sition data, and unfortunately there is no magic to manage this complexity other than a materi- als and substances database or spreadsheets to manage the list of ingredients to be reported. Some of the major CAD systems are offering functionality to select raw materials from a database coupled to the CAD system, which is logical since the designer is specifying the materials in the first place. More about how to develop basic "what's in the product" docu- mentation may be a good topic for another report, since by some accounts this is still the greatest obstacle to begin any FMD. Next, we briefly highlight important func- tional requirements for any tool used to gener- ate FMDs from materials and substance data. Ability to select substances from a list by 00 number prevents errors, since CAS (chemi- cal abstract service) number is a key for many receiving systems and is the authority tag spec- ified in the IPC standard. A CAS number lookup list should be provided in the tool, which has the advantage of speeding up data entry and selecting matches quickly from valid selections provided by the tool. The tool may also validate the format of the CAS number format itself, which must be 10 digits separated into three groups by hyphens, with the last digit being a check digit. These rules are published by CAS. This type of validation may be useful to allow newer, valid CAS numbers that are not in the lookup table to still be entered. The problem of "wildcard" or declarable/reportable substance lists will be covered in the next section, since it remains a problem in the industry. A lookup of substance names can also expe- dite entering substances data, again by ensur- ing that a valid substance name is used and a valid CAS number goes along with it. The advantage is that a substance name may be more easily recognized and used by a human than a CAS number. This approach to valida- tion has the disadvantage that compounds and even pure elements may have many differ- ent synonyms, in which case the direct CAS number lookup would be more useful. The input screen for materials and substances data may look something like Figure 2. This kind of table is the heart of an FMD, where each material is composed of its constitu- ent substances, all with reported weights in the product. Optionally, data like attachment files and concentration ranges may be accom- modated. If exemptions apply at the material level, they may also be selected. Direct entry into a reporting tool is likely to be of interest to suppliers making raw materi- als or simple components, rather than OEMs. But this data becomes the basis of creating FMDs for more complex products. Suppliers of the following kinds of items might be in the best position to take advantage of the kinds of tools being discussed here. • Solder and solder flux (separately or in paste or wire) • Bulk material like sheets, or parts made of a homogenous material • Metal alloys, or parts made from them • Wire • Mold compound; molded parts • Underfill • Conformal coating • Plating, painted or dipped coating, or other types of coating • Adhesives, lubricants or sealants FMDs for these items can allow the next tier customer to use it for reporting at the next assembly level. Companies on the more complex end of the supply chain may need to use larger enterprise systems to collect this data and run final reports, so the more basic FMD generating tools may be of less interest to them. Figure 3 shows how the data cascade Figure 2: Example of material and substance input screen. [3]