Ultra-fine pitch devices pose new PCB design issues
Ball-grid array (BGA) packages come in a variety of pitches and sizes. As device complexity increases and OEMs continue their drive toward smaller components, ball pitches of 0.5 mm and lower are becoming more popular.
Pitch is defined as the space between the center of one BGA ball to the center of the next one. Today, you find 0.4 mm pitch BGAs in virtually every smartphone, and 0.3 mm ultra-fine pitch BGAs are the next generation. Currently, the major transition taking place with a move from 0.5mm to 0.4m, initially in ASICs (application specific integrated circuits) and WLCSPs (wafer level chip scale packages).