A 12V-to-1V Outphase-Interleaved SC Hybrid Converter With Enhanced Inductor De-Energizing Slew Rate and Adaptive Deadtime Control

This brief presents a high step-down outphase-interleaved switched-capacitor hybrid converter with enhanced inductor DC current reduction and flying-capacitor (CF) inrush current suppression for 12V-to-1V voltage conversion, which is appealing in automotive and date center applications. The main novelties and contribution of this work are three folds: 1) a hybrid converter topology with well-reduced inductor DC (IL,DC) current and CF inrush current to achieve high conversion efficiency and power density for high step-down conversions, 2) an adaptive dead-time (ADT) controller for minimizing the body diode conduction loss adaptive to different load condition, and 3) a body diode series conduction (BDSC) technique for enhancing heavy-to-light load transient response. Implemented in a 180-nm Bipolar-CMOS-DMOS (BCD) process alongside total power passive components in a 4.84 mm3 volume, the proposed converter achieves a peak efficiency of 91.1% for 12V-to-1V conversion at a load current (ILOAD) of 0.8A. It retains an efficiency of 83.9% at 2.5A ILOAD. The ADT control improves light-load efficiency by ~1%. When ILOAD steps from a 2.5A to 0.5A under 12V-to-0.6V conversion, the proposed BDSC technique boosts the inductor de-energizing SR by 1.8× and reduces output overshoot by 46mV.