A Comparison between Conventional Buck and 2-pscB DC-DC Converters

Compared to conventional Buck, the automatic current sharing mechanism is one technical advantage of the two-phase series capacitor buck converter (2-pscB), but this benefit is generally not enough to justify the limitation of output load potential. The other very important advantage is the simplified control scheme with fewer current sensing loops, as claimed in the previous publication. To fill in the gap and better understand the differences between these two topologies, this paper provides a complete comparison. Theoretical and experimental analysis of 2-pscB with a signal-variation model and the parasitic component linearization are developed to design a robust controller and to satisfy the stability and performance of the converter. The current sharing tolerance mechanism and switching node voltages in the frequency domain were as predicted. Heat distribution was not that good due to the circuit layout.