A 90.4% Peak Efficiency 48V/1V Three-Level Hybrid Dickson Converter with Gradient Descent Run-Time Optimizer and GaN/Si Hybrid Conversion

Abstract

This work presents a 48V/1V DC-DC Point-of-Load (POL) converter for efficient high voltage conversion in data centers. The converter includes (1) a three-level hybrid Dickson topology with GaN/Si hybrid conversion achieving efficient flying capacitor (CF) utilization. (2) A gradient descent run-time optimizer finding optimal switching frequency (fSW) and number of fingers turned on (NF) during converter's operation. (3) A 10bit hybrid ADC for current sensing. The test chip is fabricated in 0.18m BCD process and shows a 90.4% peak efficiency at 48V-1V conversion with a 240 A/inch3 current density.