雜談GaN技術

Written by Michael de Rooij and Alana Nakata - Efficient Power Conversion

Published in: PCIM Europe 2017; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management; Proceedings of

eGaN FETs, which are available in non-traditional chip scale packages (CSP) as land grid array (LGA) and/or ball grid array (BGA) formats, have repeatedly demonstrated higher power density and higher efficiency performance than equivalent MOSFETs across various applications ^{[1, 2]}. Those improvements are contingent upon proper layout practices documented extensively in ^{[1, 3]} that minimize unwanted parasitic elements. Over the seven years since eGaN FETs were first launched into the market there have been a total of 127 device failures out of a total of more than 17 billion hours in actual use in the field, 75 of which were a result of poor assembly technique or poor printed circuit board (PCB) design practices ^[4]. Designers are becoming more familiar with the PCB design rules that affect manufacturability and are less forgiving compared to MOSFETs due to their relatively smaller sizes. This paper will cover the various guidelines for PCB design that maximize the performance of eGaN FETs and reliability yet still rely on existing PCB manufacturing capabilities.

I don’t know about you, but in my house the number of mobile devices seems to multiply overnight, along with the ways they are used.  On any given night, you may find me on a GoToMeeting conference on my laptop, my husband on a video Skype chat from his phone with his dad in Florida, my oldest son turning in an assignment on Google Classroom from his laptop, my younger son streaming videos on his tablet, and my second grader recording and posting a music.ly on her phablet.  And when we travel, these devices come with us so they need to be small and lightweight enough to come along for ride! 

This all translates into ever-increasing power demands for computing and telecom systems and the conflicting desire for small, lightweight form factors, and extended battery life. To meet these demands, point-of-load (POL) DC-DC converters (the power engines) need to be designed to be small sized and as efficient as possible. These demands translate to ever faster switching frequencies of the transistors used in the power conversion running these devices. Notebook PCs, tablets, and phablets are especially sensitive to this need as our dependency on these devices and the demands we make on them continues to grow. 

I have yet to meet someone who likes power cords.

Take for example Keith. In figure 1 is a photo of all the power-related accessories Keith lugs around in his backpack to make certain he will be able to run his phone, tablet, and computer wherever he goes. What Keith and others may not realize is that the technology is available that can eliminate every one of these cords – today! So, why is it taking so long for wireless power solutions to become a household technology?

Certainly, wireless charging is not a new topic having been talked about for quite a while. But now, with a recently developed innovative approach to the design of transmission and receiver antennae (coils), ubiquitous wireless power is ready to be incorporated into our daily lives throughout furniture, walls, and floors to efficiently and economically power all the gadgets we need for our electronic lives.

This post was originally published May 26, 2017 on the PowerPulse.net web site . Learn more about eGaN technology and EPC GaN solutions for 48 V to Point-of-Load.

During last week’s PCIM Europe event in Nuremberg, Germany, direct 48V-to-1V power conversion architectures were a significant topic, mostly outside of the exhibit floor. Vicor was quietly showing its latest generation of 48V direct-to-chip power components. Ericsson Power Modules and Efficient Power Conversion were holding invitation-only meetings where future designs of 48V direct to load power conversion architectures were the focus of the discussions. By the end of 2017, several vendors are expected to be offering dc-dc converters delivering 48V-to-1V direct conversion.

Gallium nitride (GaN) power transistors designed for efficient power conversion have been in production for seven years. New markets, such as light detection and ranging, envelope tracking, and wireless charging, have emerged due to the superior switching speed of GaN. These markets have enabled GaN products to achieve significant volumes, low production costs, and an enviable reliability reputation. All of this provides adequate incentive for the more conservative design engineers in applications such as dc–dc converters, ac–dc converters, and automotive to start their evaluation process. So what are the remaining barriers to the conversion of the US$12 billion silicon power metal–oxide–semiconductor field-effect transistor (MOSFET) market? In a word: confidence. Design engineers, manufacturing engineers, purchasing managers, and senior management all need to be confident that GaN will provide benefits that more than offset the risk of adopting a new technology. Let’s look at three key risk factors: supply chain risk, cost risk, and reliability risk.

This post was originally published on TI’s TI E2E Community “Power House” Blog. Learn more about eGaN technology here and EPC GaN solutions here.

Televisions can get their content wirelessly, but there is one set of wires they still need: those in their power cord. The consumer electronics industry has floated ideas for freeing TVs from their power cords, but this goal remains elusive. There are several reasons, such as the difficultly of meeting high-power requirements for large-screen TVs and the need for identifying an economical technology. Nevertheless, eGaN FETs could play a role in making TVs truly cordless devices.