I am looking into different methods of power supply's when I found out about switch mode power supply's. These are the type of supply's that you have in your phone charger (or at least i believe so). The type of supply I need, is something that can supply a voltage of 2.5 volts @ 70 amps, and plugs right into the wall. To do this, I would use whats called a buck converter (because it lowers the voltage). So I was looking on amazon for things that would work for me, and I found nothing anywhere. so I decided to lower my expectations, and just look for any buck converter that would work with a input of 120 volts dc from the wall, after it was rectified, and filtered, and I could find nothing. Then I tried looking into building my own power supply, given a switch ic, which I looked for, and still found nothing, that could handle an input of 120 volts. What I was wondering, was how come basically every single thing powered by the wall outlet is powered by these, if none of them can handle an input of 120 volts? And how do I find one that can. Also, how would I create my power source that can step down the main wall outlet power to 2.5 volts @ over 30 amps at least? Also, why is it that I could not find any switch ic that could handle 120 volts, if every phone charger has one that can? Do they not sell them to the public? Why is it that I could not find a Built buck converter on amazon that could handle an input of 120 volts? Could I modify a 30 volt one to work with 120 volts, or put something between the filtered dc wall current and the buck converter to do this? Thanks for the help, it is really appreciated.