Wafer-Level Chip-Scale Package (WLCSP) is a micro-SMD technology that has further advanced the miniaturization of chips
and packages. The connection concept of the Wafer-Level Chip-Scale Package (WLCSP) differs from the other BGA packages and CSP packages
inthat no additional underlay material is required. The
actual chip is bonded directly face down onto the PCB using flip-chip technology. This minimizes the inductances between the chip and the PCB. Other advantages include package size reduction, manufacturing time reduction and improved thermal conductivity. Small WLCSP package sizes are 0.65 mm x 0.44 mm and have a thickness of only 0.2 mm.