Clock cleaning and fan-out in a 7×7 QFN
The LMK03001CISQX/NOPB is a clock conditioner, not a PLL synthesizer — it takes an existing reference clock, jitter-cleans it, and fans it out to eight differential outputs. The 1.57 GHz maximum frequency sets the upper bound for the output clock; the actual rate is the input frequency divided by an integer (the part has a divider, no internal multiplier). Packaged in a 48-WQFN with an exposed pad (7×7 mm), the thermal land must be soldered to a matching copper pad on the PCB — the datasheet's recommended footprint is the reference for both thermal dissipation and ground return. The 3.15 V to 3.45 V supply rail means the board's 3.3 V regulator must hold within 300 mV tolerance; this is not a wide-VIN part. Input interfaces cover LVCMOS, LVDS, and LVPECL — a single-ended reference is accepted but converted to differential internally before conditioning. Outputs are differential only (LVDS or LVPECL); the downstream device must accept a differential clock. No single-ended LVCMOS output option exists.
1:8 fan-out for multi-ASIC clock trees
The 1:8 input-to-output ratio drives eight differential clock lines from one conditioned reference — enough to clock multiple ASICs, FPGAs, or SerDes transceivers on a line card without external fan-out buffers. The differential outputs (LVDS or LVPECL) keep signal integrity across backplane or long PCB traces. The industrial temperature grade is the selection gate for these environments.
Tape-and-reel packaging supports automated assembly.