GaN Talk Blog

Efficient Power Conversion (EPC) is doubling the performance distance between the aging silicon power MOSFET and eGaN® transistors with 200 V ratings.  The new fifth-generation devices are about half the size of the prior generation.  This performance boost comes from two main design differences, as shown in figure 1.  On the left is a cross-section of the fourth generation 200 V enhancement-mode GaN-on-Si process.  The cross-section on the right is the fifth-generation structure with reduced distance between gate and source electrodes and an added thick metal layer. These improvements, plus many others not shown, have doubled the performance of the new-generation FETs.

Packaged SEE Immune and Radiation Hardened enhancement mode gallium nitride (eGaN) devices offer dramatically improved performance over the aging Rad Hard silicon MOSFET, enabling a new generation of power converters in space operating at higher frequencies, higher efficiencies, and greater power densities than ever achievable before.

GaN FETs can switch significantly faster than Si MOSFETs causing many system designers to ask − how does higher switching speeds impact EMI?

This blog discusses simple mitigation techniques for consideration when designing switching converter systems using eGaN^® FETs and will show why GaN FETs generate less EMI than MOSFETs, despite their fast-switching speeds.

Beyond just performance and cost improvement, the most significant opportunity for GaN technology to impact the power conversion market comes from its intrinsic ability to integrate multiple devices on the same substrate. GaN technology, as opposed to standard silicon IC technology, allows designers to implement monolithic power systems on a single chip in a more straightforward and cost-effective way.

Today, the most common building block used in power conversion is the half bridge. In 2014, EPC introduced a family of integrated half-bridge devices which became the starting point for the journey towards a power system-on-a-chip. This trend was expanded with the introduction of the EPC2107 and EPC2108, which integrated half bridges with integrated synchronous bootstrap. In 2018 we further continued the integration path with the introduction of eGaN ICs combining gate drivers with high-frequency GaN FETs in a single chip for improved efficiency, reduced size, and lower cost. Now, the ePower™ Stage IC family redefines power conversion by integrating all functions in a single GaN-on-Si integrated circuit at higher voltages and higher frequency levels beyond the reach of silicon.

Dear Friends, colleagues and partners of EPC,

Happy New Year to you and your family from all of us at EPC!

2019 was a year to remember for EPC’s GaN innovations and the multiple use cases for GaN that have come to fruition. EPC’s latest generation of GaN products have enabled engineers to gain power stage advantages due to their low R_DS(on) characteristics, higher efficiency, enhanced thermal properties, small size and low cost. Now, more than ever, power system designers are switching from silicon devices to higher performance GaN components.

This post was originally published by Dr. John Glaser & Dr. David Reusch on June 13, 2016 on the Power Systems Design web site.

Comparing Dead-time Losses for eGaN FETs and Silicon MOSFETs in Synchronous Rectifiers

There have been several comparisons of eGaN FETs with silicon MOSFETs in a variety of applications, including hard-switched, soft-switched, and high-frequency power conversion. These studies have shown that eGaN FETs have large efficiency and power density advantages over silicon MOSFETs. Here we’ll focus on the use of eGaN FETs in synchronous rectifier (SR) applications and the importance of dead-time management. We show that eGaN FETs can dramatically reduce loss due to dead-time in synchronous rectifiers above and beyond the benefits of low R_DS(on)and charge.

Silicon has been around long enough. It’s time for a younger and far more fit challenger to take over semiconductor material dominance.

When I first started developing power devices 44 years ago, the “king of the hill” was the silicon power bipolar transistor.  In 1978 International Rectifier (IRF) launched power MOSFETs as a faster alternative to the slower and aging bipolar devices.  The early adopters of the power MOSFET were applications where the bipolar just was not fast enough.  The signature example for its adoption was the switching power supply for the desktop computer; first at Apple, and then at IBM. 

With advancements in motor technology, power densities have increased; motors are built in smaller form factors and designed for higher speeds, and higher precision, which requires higher electrical frequencies.

3-phase brushless DC (BLDC) motors are compact for their power ratings, can be precisely controlled, offer high electro-mechanical efficiency, and can operate with minimal vibration when properly controlled. These motors are increasingly or exclusively used in precision applications like servo drives, robotics, such as surgical robots, and drones, such as quadcopters. To keep current ripple within a reasonable range, these motors – given their low inductance – require switching frequencies up to 100kHz. A FET that can operate efficiently at high frequency is required to minimize losses and offset the torque ripple in the motor which creates vibrations, reduces drive precision and decreases efficiency.

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.