> specially an SoC, that contains DRAM that must get refreshed, IO controllers that must drive peripheral lines with to-spec line voltage, etc. I'm just nitpic

> specially an SoC, that contains DRAM that must get refreshed, IO controllers that must drive peripheral lines with to-spec line voltage, etc. I'm just nitpicking your otherwise great post here but wouldn't the IO voltages be entirely separate from the core voltage? Or do they all need to be kept within a certain range of each other?