Timing Product Families Offer Sub-200-fs Phase Jitter For PCIe Clocks

Micrel’s PL6020xxx and PL6070xxx PCI Express (PCIe) clock generators feature one, two, four, or eight outputs with sub-200-fs phase jitter and 50-ps output-to-output skew. The PL6070xxx also supports spread-spectrum technology (SST) for electromagnetic-interference (EMI) reduction. The clock synthesizers accept a fundamental crystal or 25-MHz reference input, producing output frequencies ranging from 25 to 200 MHz with 100-MHz phase-noise performance of −135 dBc at 10-kHz offset. They support 2.5- and 3.3-V power-supply operation. Along with the synthesizers comes the new SY7557xL clock distribution family. The SY75576L and SY75578L clock buffers feature four and eight outputs, respectively. Additive phase jitter measures sub-150 fs with sub-50 ps output-to-output skew, which meets requirements for PCIe-based server, storage, and networking applications. Industrial temperature range for all devices is 40 to +85°C. Packaging options include a 6-pin SOT (one output), 16-pin 3- by 3-mm QFN (two outputs), 24-pin 4- by 4-mm QFN (four outputs), or 44-pin 7- by 7-mm QFN (eight outputs).

MICREL INC.