A planar 75% efficient GaN 1.2-GHz DC-DC converter with self-synchronous rectifier

This paper presents the design and characterization of a DC-DC converter operating at 1.2GHz with a maximum efficiency of 75% at 4.6W output power, and with a maximum output power of 13W at 58% efficiency. The microwave converter consists of a GaN class-E power amplifier coupled to a GaN class-E rectifier. The circuit is planar and exhibits a power density of approximately 0.65W/cm
³
at the 75% efficiency point. The rectifier can be operated with input gate drive or selfsynchronously with a single RF input.