General Description
The ICS9DB423B is compatible with the Intel DB400Q
Differential Buffer Specification. This buffer provides 4
PCI-Express SRC or 4 QPI clocks. The ICS9DB423B is
driven by a differential output pair from a CK410B+ or
CK509B main clock generator.
Recommended Application
DB400Q compatible part with PCIe Gen1, Gen 2 and QPI
support
Key Specifications
• Output cycle-cycle jitter < 50ps
• Output to Output skew <50ps
• Phase jitter: PCIe Gen1 < 86ps peak to peak
• Phase jitter: PCIe Gen2 < 3.0/3.1ps rms
• Phase jitter: QPI < 0.5ps rms

Features/Benefits
• Spread spectrum modulation tolerant, 0 to -0.5% down
spread and +/- 0.25% center spread
• Supports undriven differential outputs in Power Down
and DIF_STOP# for modes for power management.
Output Features
• 4 - 0.7V current-mode differential output pairs
• Supports zero delay buffer mode and fanout mode
• Bandwidth programming available
• 50-133 MHz operation in PLL mode
• 33-400 MHz operation in Bypass mode