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Lidar time-of-flight distance measurement has become the primary means of high-speed, accurate mapping of 3-D space. It has uses in diverse applications from surveying to real-time autonomous vehicle navigation. A key lidar subsystem is the pulsed laser transmitter, which must generate high power optical pulses with duration < 10 ns. This work describes a laser driver using commercial GaN FETs to achieve a high power, high speed pulse laser driver capable of operating from an 80 V bus, and can generate current pulses into a laser diode of 60 A peak current with a 5 ns duration.

With the power architecture transition from a 12 V to 48 V rack in modern data centers there is an increased interest in improving 48 V power conversion efficiency and power density. In this paper, we will explore system optimization of 48 V to 12 V non-isolated, fully regulated, intermediate bus converters (IBC) to maximize efficiency and power density. A GaN-based three level converter provides a 50% reduction in inductor volume and a 25% reduction in converter power loss.

Higher power density GaN FETs have traditionally relied on cooling from junction-to-board into the PCB. This paper explores a thermal cooling method suitable for eGaN FETs that eliminates mechanical stresses during assembly and yields excellent thermal performance using a liquid thermal interface material. A 140 V to 28 V Buck converter, capable of delivering 34 A (1kW) was designed and built. Tests were performed using forced air cooling on the PCB and repeated with the proposed thermal solution that resulted in more than a 4x increase in output current capability.

In this paper, high output impedance eGaN FETs based class E amplifiers are investigated for suitability in coupled transmit coil wireless power systems. Experimental results show evidence that high output impedance class E amplifiers are inherently isolated from each other in this configuration and therefore also balance load sharing for receivers that straddle across two or more coils. Furthermore, only eGaN FET based class E amplifiers can simultaneously achieve high efficiency and high output impedance making them ideal for this application.