What the 800 MHz ceiling and dual PLL mean for a timing tree
The LMK05318RGZR is a clock synchronizer and jitter cleaner that accepts LVCMOS or standard clock inputs and synthesises up to eight outputs in CML, HCSL, LVCMOS, LVDS, or LVPECL formats. Its 800 MHz maximum output frequency covers the common SerDes reference clock range — 156.25 MHz, 312.5 MHz, and 625 MHz — with margin for the PLL loop bandwidth to attenuate upstream jitter before the signal reaches the transceiver. The dual PLLs with bypass let one path clean a noisy reference while the other generates a separate frequency domain, or bypass the PLL entirely for a clean-through mode when the input is already low-jitter.
The base product number LMK05318 covers multiple output-format and package variants — confirm the full RGZR suffix matches the BOM line before committing.