The MK1491-06 is a low cost, low jitter, high performance clock synthesizer for National Semiconductor CS5530 based computer and portable appliance applications. Using patented analog Phase-Locked Loop (PLL) techniques, the device accepts a 14.318 MHz crystal input to produce multiple output clocks. It provides selectable PCI local bus and AC97 audio clocks, 24 MHz and 48 MHz clocks for Super I/O and USB, as well as multiple Reference outputs.