A buck converter uses flying capacitors and cross coupling. The flying capacitors reduce the voltage stress across the inductors and the devices, and may provide high efficiency at very low duty cycle ratios. In addition to the high efficiency performance, the converters may provide a significant reduction in area, since smaller inductors can be used compared to typical buck converters. An example of realization shows up to 90% efficiency at 0.5V output and 10 A load from a 3.6V input with small flying capacitors, compared to what is typically used in a switched capacitor converter.