A 24/48V to 0.8V-1.2V All-Digital Synchronous Buck Converter with Package-Integrated GaN power FETs and 180nm Silicon Controller IC

This paper presents a 24V/48V input, 0.8V- 1.2V output, two-phase, single-stage point-of-load (PoL) synchronous buck converter with enhanced-mode Gallium Nitride (GAN) N-FET based output stage and 180nm HV BCD silicon based all-digital control. The GaN devices, silicon controller chip and bootstrapping (BST) capacitors are heterogeneously integrated on an organic package substrate, thus providing a System in Package (SiP) solution, to enable high efficiency (>76% for 48:1, >86% for 24:1) while delivering 10.52W at 1V at a switching frequency of 5MHz, with a net Figure of Merit (FoM) of 11,520 MHz•V - a 13% improvement over the state-of-the art (SoA).