A Resonant Dual-Path Interleaved DC-DC Converter With Reduced Input RMS Current, 0.5 W/mm^2 Power Density and 91.6% Peak Efficiency

This paper presents a novel resonant DC–DC converter topology that combines dual-path power delivery with interleaved operation and capacitor soft charging to increase power density and power efficiency. Small-signal analysis based on a modular averaged model of the converter demonstrates that the duty cycle-to-output transfer function maintains an effective second-order response within the control bandwidth, facilitating robust closed-loop regulation using standard PID control. Fabricated in a 0.18-μm BCD technology, the chip is co-designed with a PCB interposer to enable vertical stacking of passive components and leverage parasitic inductance. The converter operates from a 4.0–5.0-V input and delivers up to 7A over a 0.75–1.2-V output range. Experimental results demonstrate a peak efficiency of 91.6% and a power density of 0.5W/mm2, achieving state-of-the-art performance for these conversion ratios.