IDT's PLL-based clock generators offer sub-picosecond jitter, low-skew clock outputs, and edge rates that meet the ever-growing demands of today's networking solutions. The 871S1022 is a PLL-based clock generator specifically designed for PCI Express® Clock Generation applications. The device generates 100MHz, 125MHz, 250MHz or 500MHz from either a 25MHz fundamental mode crystal or a 100MHz recovered clock. The 871S1022 has two modes of operation: (1) high frequency jitter attenuator and (2) high performance clock synthesizer mode. When in jitter attenuator mode, the 871S1022 is able to both suppress high frequency noise components and function as a frequency translator. Designed to receive a jittery and noisy clock from an external source, the 871S1022 uses FemtoClock® technology to clean up the incoming clock and translate the frequency to one of the four common PCI Express® frequencies. When in synthesizer mode, the device is able to generate high performance SSC and non-SSC clocks from a low cost external, 25MHz, fundamental mode crystal. The 871S1022 uses FemtoClock® technology to generate low noise clock outputs capable of providing the seed frequencies for the common PCI Express® link rates.