1:4 fanout at 250 MHz — the fanout ceiling for single-ended clock trees
The LMK1C1104DQFT is a 1:4 clock buffer from Texas Instruments, accepting a single LVCMOS or clock input and distributing it to four LVCMOS outputs at up to 250 MHz. The non-differential I/O (No/No) limits it to single-ended clock trees — it will not fan out a differential pair like LVDS or HCSL without an external converter. The 250 MHz ceiling is the maximum toggle rate the buffer can pass cleanly; the actual usable frequency in a design depends on the trace length and load capacitance on each output leg, but the buffer itself does not become the bottleneck below that limit.
The 8-WSON (2x2 mm) package with an exposed thermal pad requires a PCB land pattern that ties the pad to a ground plane for heat spreading — the datasheet's recommended footprint is the reference.
Active production — no last-time-buy pressure
Because the buffer is a single-supply, non-differential fanout part, it is a common BOM item with multiple second-source equivalents from other vendors — but no pin-compatible TI alternative is listed as a direct successor. The 1:4 ratio and 250 MHz ceiling are the two specs that define the drop-in fit.