The Renesas 932SQ420DKLFT is a PLL-based clock synthesizer designed specifically for the Intel Romley server platform. It takes a single crystal input and generates up to 19 HCSL outputs at frequencies up to 146.7 MHz, making it the central clock distribution device on a Romley-generation motherboard or server blade. The 1:19 fanout ratio means one crystal reference feeds nearly two dozen differential clock lanes—saving multiple discrete buffers and reducing jitter accumulation.
Output type and differential signalling
All outputs are HCSL (High-Speed Current Steering Logic), the standard differential signalling for PCIe reference clocks. The input side is single-ended (crystal), while the output side is differential (Yes/No for input/output respectively). This is a common architecture: a clean crystal oscillator feeds the PLL, and the PLL generates multiple differential pairs. The differential outputs reduce common-mode noise coupling on long board traces to PCIe slots or chipset.