Not so tumbelweed.
With Linear regulators, your Input current is the same with the output current! Beware of that! Plus the current of the regulator of course, though this is small enough.
The opposite happens with SMPS. In that case wattage is the same plus the losses in the regulator itself.
The voltage drop with increased load is called Load Regulation and is there in the specs. And of course it is different for every regulator, either linear or SMPS. Besides that spec, which is typically small enough (less that 1% for the TPS565208), the voltage will drop for many other reasons, like design of PCB, part selection, thickness of wires and the point where output voltage sample is taken for the regulator to compensate for. the drop.
More output current, more copper on PCB and thicker wires are needed. After all, the regulator will have the nominal voltage on the output but if your wire is 10 meters long, you will have voltage drop on the cable, right?
I think TPS565208 is one of the easiest to handle and very good in terms of cost, pcb estate, output noise and efficiency.
Ioannis
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