Clock fanout with signal-type translation
The LMK00101SQE/NOPB is a fanout buffer, multiplexer, and translator — it accepts one of three input signals and distributes it to up to ten output paths, while also translating between differential and single-ended logic families. Inputs accept HCSL, LVCMOS, LVDS, LVPECL, LVTTL, SSTL, or a crystal oscillator; outputs are LVCMOS or LVTTL. The differential input path is available, but the outputs are single-ended.
200 MHz ceiling and 3:10 fanout ratio
Maximum frequency is 200 MHz — this sets the upper limit for the clock distribution tree. For a 100 MHz reference, the device has margin; for a 156.25 MHz Ethernet clock, it still fits within the rated ceiling. The 3:10 input-to-output ratio means three input pins feed ten outputs. The multiplexer selects one of the three inputs; the selected signal is buffered and fanned out to all ten outputs.
The wide range allows the same BOM line to serve multiple board variants without a regulator change.
32-WQFN package and board integration
The 0.50 mm pitch requires a 4-layer board for fan-out of the inner rows.