Quad 4A/2A step-down — load allocation and rail assignment
The TPS65400RGZT from Texas Instruments is a four-output synchronous buck regulator that delivers 4 A on two channels and 2 A on the other two, all from a single 4.5 V to 18 V input rail. The adjustable outputs down to 0.6 V make it a direct fit for powering FPGAs, SoCs, and multi-rail processor cores where each voltage domain needs its own regulator with independent sequencing.
Switching frequency range — inductor sizing vs efficiency trade-off
Running at the low end minimises switching losses and lets you use a larger inductor with lower DCR for better efficiency at heavy loads. At the high end, you shrink the inductor footprint and output capacitor bank — useful when board area is tight, though at the cost of slightly higher FET switching losses.
For a quad-rail power management IC that often gets designed into multi-year industrial or telecom platforms, this means you can commit the BOM without worrying about a last-time-buy window opening mid-production.