The VSC8163 is a 16:1 multiplexer with integrated clock generator for use in SONET/SDH systems operating at a 2.48832Gb/s data rate. The internal clock generator uses a Phase-Locked Loop (PLL) to multiply either a 77.76MHz or 155.52MHz reference clock in order to provide the 2.48832GHz clock for internal logic and output retiming. The 16-bit parallel interface incorporates an on-board FIFO, eliminating loop timing design issues by providing a flexible parallel timing architecture. The device operates using a +3.3V power supply, and is packaged in a thermally-enhanced plastic package. The thermal performance of the 128PQFP allows the use of the VSC8163 without a heat sink under most thermal conditions.