On the operating speed and energy efficiency of GaN-based monolithic complementary logic circuits for integrated power conversion systems

Abstract

Gallium nitride (GaN)-based power conversion systems exhibit striking competitiveness in realizing compact and high-efficiency power management modules. Recently emerging GaN-based p-channel field-effect transistors (FETs) and monolithic integration techniques enable the implementation of GaN-based complementary logic (CL) circuits and thereby offer an additional pathway to improving the system-level energy efficiency and functionality. In this article, holistic analyses are conducted to evaluate the potential benefits of introducing GaN CL circuits into the integrated power systems, based on the material limit of GaN and state-of-the-art experimental results. It is revealed that the propagation delay of a single-stage CL gate based on the commercial p-GaN gate power HEMT (high-electron-mobility transistor) platform could be as short as sub-nanosecond, which sufficiently satisfies the requirement of power conversion systems typically with operating frequencies less than 10 MHz. With the currently adopted n-FET-based logic gates (e.g., directly coupled FET logic) replaced by CL gates, the power consumption of peripheral logic circuits could be substantially suppressed by more than 103 times, mainly due to the elimination of the pronounced static power loss. Consequently, the energy efficiency of the entire system could be substantially improved.