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
$(C_{\mathrm{ F}})$
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 brief are three folds: 1) a hybrid converter topology with well-reduced inductor DC
$(I_{L,DC})$
current and
$C_{\mathrm{ F}}$
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
$(I_{\mathrm{ LOAD}})$
of 0.8A. It retains an efficiency of 83.9% at 2.5A
$I_{\mathrm{ LOAD}}$
. The ADT control improves light-load efficiency by ~1%. When
$I_{\mathrm{ LOAD}}$
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\times $
and reduces output overshoot by 46mV.