Transient response comparison of voltage mode and current mode control on output-inductorless two-stage DC-DC converter

The two-stage DC-DC converter is developed for power supply of telecommunication application. This converter consists of a buck topology in the first stage and a half-bridge topology in the second stage. In order to reduce the system order, the output inductor is removed form this topology, then this system can be treated as a second-order system in approximation. As a result, the stability and the transient response are improved. Further improvement is required. This paper presents the effect of current mode control on the transient response in an output-inductorless two-stage DC-DC converter. As a result, output voltage drop is reduced by around 25% and the settling time is reduced by around 36% when compared with the voltage feedback control, and the effectiveness of the current mode control is experimentally confirmed.