1.6 GHz clock fanout — what the 2:8 ratio means for your clock tree
The LMK01000ISQX/NOPB is a fanout buffer (distribution) and divider from Texas Instruments, designed to take one or two differential clock inputs and distribute them to up to eight LVDS or LVPECL outputs. The 2:8 input-to-output ratio means you can route a clean reference clock to multiple destinations — ADCs, FPGAs, or SerDes transceivers — without loading the source oscillator. With a maximum frequency of 1.6 GHz, this buffer handles high-speed serial links (Gigabit Ethernet, PCIe Gen 1/2, or 10G backplane clocks) where edge jitter matters more than the absolute frequency. The differential input and output path (yes/yes) preserves signal integrity across the distribution network.
Supply rails and temperature grade
The device operates from a 3.15 V to 3.45 V supply — a tight window that demands a clean rail. A low-noise LDO feeding this buffer is standard practice; the 48-WFQFN exposed pad (7x7 mm) provides a thermal path to the ground plane, which also serves as the return for the high-frequency outputs.