3.1 GHz fanout buffer — universal clock translation in one package
The Texas Instruments LMK00301SQ/NOPB is a 3:10 fanout buffer, multiplexer, and level translator that handles the widest set of differential clock standards on the input side — CML, HCSL, HSTL, LVDS, LVPECL, SSTL, and even a crystal — and outputs HCSL, LVCMOS, LVDS, or LVPECL. That means a single device can replace a rack of dedicated translators on a multi-protocol clock tree, whether you're distributing a 100 MHz reference to ten FPGA banks or a 3.1 GHz SerDes clock to multiple transceivers. The 3:11 input-to-output ratio gives three selectable input muxes feeding ten outputs (the datasheet counts it as 3:10 in the description), which is enough to fan out a master clock to every PLL and SerDes on a dense board without adding external dividers or redrivers.
3.15V–3.45V supply — plan the rail
The supply range is 3.15V to 3.45V, which is a ±4.5% window around a nominal 3.3V rail. That's tighter than the ±10% many logic parts tolerate, so the 3.3V rail feeding this buffer needs a regulator with good load regulation — a standard 3.3V LDO with 1% accuracy is fine, but don't try to run it off a 3.0V or 3.6V rail without checking the margin. The device draws its current from this single rail; there's no separate core or I/O supply.
The 7x7 mm 48-WQFN with exposed pad is a standard QFN package, but the thermal pad underneath is the main heat path — and the main rework challenge. The exposed paddle needs a via-stitched thermal land on the PCB; without it, the junction temperature climbs fast above 400 mA continuous output drive.
The base product number is LMK00301, so any future variants (different package or temperature grade) would carry that prefix.
If you're dual-sourcing for supply resilience, the closest functional peer is the CDCLVP1204RGTR, but note that part tops out at 2.0 GHz and only outputs LVPECL, so it's not a pin-for-pin drop-in; the LMK00301's wider frequency range and multi-standard output flexibility are the differentiators for a high-speed mixed-signal clock tree.