This post was originally published by M. Di Paolo Emilio on the Power Electronic News web site.

Power switching devices based on gallium nitride technology (GaN) are in volume production now and delivering high efficiency and power density in real-world power applications. This article will examine how to implement high-power solutions with GaN technology, presenting application examples that demonstrate how GaN devices can effectively work even beyond 600 volts.

GaN devices differ from best-in-class field-effect transistors (FETs) and other silicon-based components in several important respects. GaN devices enable solutions that increase power density by two or more times over silicon-based approaches. As a result, component and package size can be reduced, yielding a solution with a smaller PCB footprint. GaN devices also offer higher efficiency than their silicon predecessors, albeit at a comparably higher overall system cost.

eGaN® FET-based power conversion systems offer higher efficiency, increased power density, and lower overall system cost than Si-based alternatives. These advantageous characteristics have spurred the presence of an ever increasing ecosystem of power electronics components such as gate drivers, controllers, and passive components that specifically enhance eGaN FET performance. Some examples of eGaN FETs are shown in figure 1.

The latest generation of 100 V GaN devices increase the efficiency, shrink the size, and reduce system cost for 48 V power conversion. The EPC2045, shown in figure 1, is rated at 100 V with 7 mΩ on- resistance that can carry a continuous current of 16 A. The EPC2045 is nearly one-tenth the footprint of a comparable Si MOSFET and has lower parasitic capacitances and can switch much faster than equivalent silicon devices, yielding lower switching loss even at higher switching frequency.

The EPC2053, shown in figure 2, is rated at 100 V with 4 mΩ on-resistance that can carry a continuous current of 32 A. The EPC2053 has lower parasitic capacitances and on-resistance than its silicon counterparts, yielding faster switching speed and lower power losses even at higher switching frequencies. These characteristics enable increasing the output power while shrinking the volume of the converter.

Motivation

The rapid expansion of the computing and telecommunication market is demanding an ever more compact, efficient and high power density solution for intermediate bus converters. The LLC resonant converter is a remarkable candidate to provide a high power density and high-efficiency solution. eGaN^® FETs with their ultra-low on-resistance and parasitic capacitances, benefit LLC resonant converters by significant loss reduction that is challenging when using Si MOSFETs. A 48 V to 12 V, 900 W, 1 MHz LLC DC to DC transformer (DCX) converter employing eGaN FETs such as EPC2053 and EPC2024 is demonstrated, yielding a peak efficiency of 98.4% and a power density exceeding 1500 W/in³.

The rapid expansion of the computing and telecommunication market is demanding an ever more compact, efficient and high power density solution for intermediate bus converters. The LLC resonant converter is a remarkable candidate to provide a high power density and high efficiency solution. eGaN® FETs with their ultra-low on-resistance and parasitic capacitances, benefit LLC resonant converters by significant loss reduction that is challenging when using Si MOSFETs. A 48 V to 6 V, 900 W, 1 MHz LLC DC to DC transformer (DCX) converter employing eGaN FETs such as EPC2053 and EPC2023 is demonstrated, yielding a peak efficiency of 98.1% with a specific power of 48 W/cm2 (308 W/in2) and power density of 69 W/cm3 (1133 W/in3).

As the new year starts, it is worth spending a few minutes to review the successes of 2018 and look ahead to expectations for 2019. 

Over the past year, the applications taking advantage of GaN’s superior performance continued to expand and the knowledge base of GaN users continued to broaden.  The world has seen in operation the autonomous vehicles that GaN enables. Digital communications have been vastly improved with the use of GaN FETs and ICs in high speed, energy saving envelope tracking power supplies. The dream of a wireless world is coming closer to reality with the emergence of large surface area wireless power.

World-changing innovations such as the first video cassette recorder (VCR) in 1970 to the world’s first laptop that can charge wirelessly have been announced at CES, the worlds gathering place for innovation.

World-changing innovations and Gallium Nitride (GaN), a critical building-block component behind many of today’s new and exciting consumer technology innovations such as self-driving cars, robots, drones, wireless power solutions, world-class audio and cutting-edge automotive solutions go hand in hand.

eGaN FETs and ICs enable very high-density power converter design, owing to their compact size, ultra-fast switching, and low on-resistance. The limiting factor for output power in most high-density converters is junction temperature, which prompts the need for more effective thermal design. The chip-scale packaging of eGaN also offers six-sided cooling, with effective heat extraction from the bottom, top, and sides of the die. This application note presents a high-performance thermal solution to extend the output current capability of eGaN-based converters.

This post was originally published by Bill Kleyman on November 5, 2018 on the Data Center Frontier  web site. Learn more about eGaN technology and EPC GaN solutions for the Data Center.

The data center is an ever-changing entity and part of our technological landscape. But sometimes the biggest changes in the colocation industry happen at the core of what makes a data center tick, and may not be visible at first glance. In this instance, we’re talking about data center power, and the potential of creative solutions on the market, such as using Gallium nitride (GaN) in power conversion equipment.

Minimal invasive surgery using surgical robots gives unprecedented control to surgeons looking to achieve the next level of precision, thereby reducing risk and trauma to the patient and speeding recovery. Many motors are required to control the various robotic appendages, such as arms, joints, and tool control, that give the surgical robot the required degrees of freedom (DOF) and dexterity to perform extremely delicate tasks. Weight and size of motor control circuitry are thus important factors in the design of such robots as they directly impact the size of the motor that manipulates the robot’s appendages during surgery.

The motor of choice for robotic surgery is the 3-phase brushless DC (BLDC) motor These motors are compact for their power rating, can be precisely controlled, offer high electro-mechanical efficiency, and can operate with minimal vibration when properly controlled. The choice of motor voltage lies in the range of 24 V to 48 V with balancing power conductor thickness and weight with insulation thickness and stiffness for optimum performance and dexterity being the determining factors.