A pseudo-CCM buck converter with freewheel switching control

This paper presents a new switching buck converter operating in pseudo-CCM (continuous conduction mode) with freewheel switching control. Compared with conventional buck converters, it can handle large current stress with small current ripple. In addition, because there is only one low-frequency single pole in the power-stage transfer function, large loop-gain bandwidth and thus fast transient response become easily achievable by a proper compensation technique. Simulation results verify these features in frequency and time domains respectively. The design provides a good solution to high-current fast-transient power supplies.