A method comprises during a first half cycle, configuring a first switch to operate as an always-on switch, turning on a second switch prior to turning on a third switch and turning off the third switch prior to turning off the second switch, wherein the first switch and the second switch are connected in series and further in parallel with the third switch between a first terminal of a power source and a filter and during a second half cycle, configuring a fourth switch to operate as an always-on switch, turning on a fifth switch prior to turning on a sixth switch and turning off the sixth switch prior to turning off the fifth switch, wherein the fourth switch and the fifth switch are connected in series and further in parallel with the sixth switch between a second terminal of the power source and the filter.