Issue link: https://iconnect007.uberflip.com/i/1050827
18 PCB007 MAGAZINE I NOVEMBER 2018 Rome Was Not Built in a Day They say that "Rome was not built in a day." Similarly, develop- ing advanced addendums with sev- eral parameters to fulfill is not com- pleted by just snapping your fin- gers either. After several webinars and meet- ings, the task group found that ad- dendums in the industry for med- ical device applications require a different approach than automo- tive. The demands and specifica- tions that need to be considered are quite dif- ferent. The challenge is to define what speci- fications can apply and work for PCBs in both small sensors on and under the skin, to larger medical equipment. We have identified that PCBs used in sev- eral applications—such as implants and hear- ing aids—have line widths, thicknesses, hole sizes, and other features below current tol- erances and limits in today's design, perfor- mance, and acceptability standard. Imper- fections in the material that in a typical PCB would be acceptable may cause application failures in these products. Volume manufac- turers of standard PCBs accept a waiver of IPC's test frequency requirements, while sup- pliers of these small PCBs must exceed the standards! IPC Design Producibility Levels "Micro PCB" is a new term recently used in discussion with members of the IPC TAEC (Technical Activities Executive Committee). We ended up with a completely new termi- nology, which we now call "design produc- ibility level D." We are pushing IPC design standards (the IPC-2220 series) to be more up to date. This will take time to implement globally within IPC, but thanks to the min- iaturization in some medical device applica- tions, these standards will be the first to use the new term. In the IPC-2220 series, IPC refers to de- sign producibility levels of features, toleranc- es, measurements, assembly, testing of com- pletion, and verification of the manufacturing In an industry where failures can be fatal, the development of rigid standards is neces- sary. My thoughts the entire way, and the idea behind the addendum, was to find a consen- sus in the jungle of corporate specifications— a common document describing basic PCB re- quirements for medical device applications. We collected all learnings from developing the addendum for the automotive industry and tried to do the same with medical. When developing a new standard, experienc- es from the complete production chain is vital, which is why it is so important to have prod- uct owners in the task group. The task group has met on a regular basis to discuss and solve challenges, discover new ones, and sometimes argue before finally agreeing. Working with standards like this often provides the feeling of one step forward, two steps back. It's hard work, but it's important. When the new standards are approved, man- ufacturers of PCBs can rely on specific stan- dards for production. The requirements and parameters for building and supplying PCBs for the medical device applications will then increase in reliability and transparency. In the development of these two standards, we have come to a point where we have agreed on most of the requirements and are ready to write a draft document for each of the two standards for the industry to review. We have recently been working in two subgroups focus- ing on important segments that soon will be presented for the larger group where a consen- sus will hopefully be reached.