All GaN Power Integration: Devices to Functional Sub-circuits and Converter ICs

This article reports the Au-free GaN power integration platform and a complete integration scheme from devices to functional subcircuits and to application-oriented GaN converter ICs. The design and experimental demonstration of all-GaN dc–dc converter IC with high level of integration is presented. Through the developed GaN power integration platform, devices are monolithically integrated and functional subcircuits are demonstrated, which have realized expected application-oriented functions and are feasible for high-level integration. The all-GaN converter IC with monolithically integrated high-side gate driver, pulse-width modulation (PWM) feedback controller, and over-current protection circuits are proposed, numerically analyzed, experimentally demonstrated, and characterized. It can realize stable 10-V output with constant output ripples below 4% from 15–30-V input line voltage. Stable output with constant ripples can be maintained according to the designed feedback control when input and load conditions are abruptly changed. When subjected to over-current incident, the converter IC can be protected according to the desired over-current threshold values within one duty cycle period. The developed all-GaN power integration platform, together with functional subcircuits and dc–dc converter IC, can be a practical verification of all-GaN IC scheme oriented toward power conversion application, and a useful reference for all-GaN IC designs.