topology of the TPS54A20, a ferocious low voltage buck converter
the current is bucked back and forth through the series capacitor
notice the lack of output rectifier! switching the inductors at the correct time results in steady DC output. also the topology makes heavy use of the mosfet flywheel body diodes to conduct.
from here:
http://www.ti.com/product/tps54a20?HQS=pwr-dcs-swift-tps54a20-pr-pf-null-wwe
