Issue link: https://iconnect007.uberflip.com/i/1470111
88 DESIGN007 MAGAZINE I JUNE 2022 standard grid was some- thing that just made sense to me. us, the idea of sol- derless assembly was tied together and accompanied by a notion that all SMT IC packaging industry (which had allowed lead pitches and formats to explode in the conversion to SMT) in the future could/should minimize the number of lead pitches, preferably to a single, standard base grid pitch akin to the beauty and simplicity of the ear- lier 100 mil pitch. From a single base, the package developer could depopu- late to meet the majority of IC package needs. e suggestion was 0.5 mm and that all package designs have terminations on that grid—making design lay- out much simpler. Fur- ther, it was suggested that all terminations be simply copper (i.e., no solderable finishes such as solder, nickel-gold, or the like). Because no solder would be used in assembly (all connections would be made by copper plating), the devices would not be subjected to high temperature processes associated with first attaching solder balls at high temperature, then mounting them to a PCB with one or more additional thermal cycles, which cumu- latively reduce device and substrate reliability. Several years ago, I wrote a short, simple book on the Occam Process titled Solderless Assembly for Electronics—the SAFE Approach 2 . While, it did not make the New York Times best-seller list, it has nevertheless enjoyed decent circulation for a technical book. But it occurred to me that I could simplify my mes- sage further and set my sights on creating a one-page comparison of Occam with tradi- tional PCB manufacture and assembly that anyone might be able to understand. I am providing that list (Table 1) along with a pic- ture of a LEGO "module" that Vern Solberg, my long-time friend and colleague, created at my request with the LEGOs and my simple instructions to visually illustrate the idea in a way anyone might understand. e purpose was to help the customers of Tessera, the pio- neering chip-scale packaging company where we both worked in the mid-1990s, to visual- ize and appreciate the huge potential value of using a common pitch for all devices. Darren Smith, the brilliant electronic interconnect designer and colleague, went a step further to demonstrate the potential 3 by reducing his Figure 1: Photo of a mock electronic module created using LEGO bricks in 1995 to visually illustrate the compelling advantage of using components all having standard grid pitch for terminations—making the potential for design layout and routing much simpler.