I don't think I've ever seen any design that didn't have decoupling caps across the power lines. I mean, the Murata parts I use have dozens of megaohms of resi

I don't think I've ever seen any design that didn't have decoupling caps across the power lines. I mean, the Murata parts I use have dozens of megaohms of resistance at DC, and the chip is off 90% of the time anyway so there's no energy loss keeping the E-field charges in the cap when the SoC is only drawing whatever miniscule amount of power it needs when it's asleep. Anyway, TI has stuff like this specifically designed for these applications, so it's kind of a nonissue these days: http://www.ti.com/lit/ds/symlink/tps62730.pdf http://www.ti.com/lit/ds/symlink/tps62730.pdf I think Mouser had them for like $0.50 or something.