9ZX21901C

19-Output Differential Zbuffer for PCIe Gen2/3 and QPI 9ZX21901C DATASHEET General Description The 9ZX21901 is Intel DB1900Z Differential Buffer suitable for PCI-Express Gen3 or QPI applications. The part is backwards compatible to PCIe Gen1 and Gen2. A fixed external feedback maintains low drift for critical QPI applications. In bypass mode, the 9ZX21901 can provide outputs up to 400MHz. Recommended Application 19-output PCIe Gen3/QPI buffer with fixed feedback for Romley platforms Output Features 19 – 0.7V current mode differential HCSL output pairs Key Specifications Cycle-to-cycle jitter: < 50ps Output-to-output skew: <65ps Input-to-output delay: Fixed at 0 ps Input-to-output delay variation: <50ps Phase jitter: PCIe Gen3 < 1ps rms Phase jitter: QPI 9.6GB/s < 0.2ps rms Features/Benefits Fixed feedback path/ 0ps input-to-output delay 9 Selectable SMBus addresses; Multiple devices can share same SMBus segment 8 dedicated OE# pins; hardware control of outputs PLL or bypass mode; PLL can dejitter incoming clock Selectable PLL BW; minimizes jitter peaking in downstream PLL's Spread spectrum compatible; tracks spreading input clock for EMI reduction SMBus Interface; unused outputs can be disabled 100MHz & 133.33MHz PLL mode; legacy QPI support Undriven differential outputs in Power Down mode for maximum power savings Functional Block Diagram OE(12:5)# 8 DIF_IN DIF_IN# Z-PLL (SS Compatible) Bypass path HIBW_BYPM_LOBW# 100M_133M# CKPWRGD...