1.6 GHz fanout buffer in a 7x7 mm QFN
The LMK01020ISQX/NOPB is a 1:8 fanout buffer and divider from Texas Instruments, accepting a differential clock input and delivering eight LVPECL outputs at frequencies up to 1.6 GHz. The 1:8 ratio means a single clean clock source can feed eight downstream PLLs, ADCs, or FPGAs without adding a second distribution stage.
What the 1.6 GHz ceiling and LVPECL output mean for your clock tree
Rated for 1.6 GHz maximum input frequency, this buffer covers the full range of common telecom and data-converter reference clocks — 10 MHz to 1.6 GHz — without needing a different part for the lower end. The LVPECL output swing is a differential 800 mV typical into 50 Ω to VCC-2V, which is the standard level for driving high-speed ADC clock inputs and SiGe PLL reference pins. The differential input and output path (Yes/Yes per the spec) means the part preserves the common-mode rejection of the incoming clock — a single-ended clock requires an external balun or AC-coupling with a bias network before the input pins. The 3.15 V to 3.45 V supply rail is tighter than a typical 3.3 V ±10 %; the 300 mV window keeps the LVPECL output swing and the internal divider logic within their linear range, so the decoupling on the 3.3 V plane should be local and low-ESR.