Issue link: https://iconnect007.uberflip.com/i/1527613
8 DESIGN007 MAGAZINE I OCTOBER 2024 Sometimes, a little technology is all you need. Star Trek's Borg character only needs a funky eyepiece contraption to access all e Collective's data, like an outer space Wi-Fi. Like the Borg's eyepiece, we may only need a little bit of HDI in one corner of the board. We might only need partial HDI. As the name suggests, partial HDI refers to the targeted use of HDI, usually on one section of one layer of the board. It offers designers an avenue for escape routing from BGAs with a pitch of 0.5 mm or less, when a mechanically drilled plated through-hole is impossible. With HDI relegated to one layer of the board, fab- ricators can avoid the expense of sequential lamination cycles. is process doesn't cost much, nor does it have a long learning curve. However, design- ers using partial HDI must navigate a variety of signal integrity and DFM trade-offs. e ultra- thin layer of laminate that this option demands is unreinforced, which can create challenges. The Shaughnessy Report by Andy Shaughnessy, I-CONNECT007 Are You Partial to Partial HDI?