TPS61230 as BOOST, 4V input, 5.4V output, drive two 5V/500mA to USB HOST, the first way uses LDO (TPS73501) output 5V, the second way uses PMOS switch (SIS435DNT) direct output, each output will have a 220uF tantalum capacitor. TPS61230 was occasionally damaged during use, up to 50%.