Digital controlled dead-time for tri-mode buck-boost DC-DC converters

This paper introduces a unique digital controller for a tri-mode non-inverting buck-boost DC-DC converter that optimizes the switching dead-times to eliminate the cross-conductions and body-diode conductions. A hybrid digital pulse width modulator (DPWM) is developed to implement trailing-edge, leading-edge modulation at high switching frequencies. An improvement in peak power conversion efficiency of 4% in the boost mode is observed, with output current ranging from 0 to 6A.