-
Researchers at the Indian Institute of Science (IISc) have developed a fully indigenous gallium nitride (GaN) power switch that can have potential applications in systems like power converters for electric vehicles and laptops, as well as in wireless communications. The entire process of building the switch – from material growth to device fabrication to packaging – was developed in-house at the Centre for Nano Science and Engineering (CeNSE), IISc.
Due to their high performance and efficiency, GaN transistors are poised to replace traditional silicon-based transistors as the building blocks in many electronic devices, such as ultrafast chargers for electric vehicles, phones and laptops, as well as space and military applications such as radar.
“It is a very promising and disruptive technology,” says Digbijoy Nath, Associate Professor at CeNSE and corresponding author of the study published in Microelectronic Engineering. “But the material and devices are heavily import-restricted … We don’t have gallium nitride wafer production capability at commercial scale in India yet.” The know-how of manufacturing these devices is also a heavily-guarded secret with few studies published on the details of the processes involved, he adds.
Power switches are used to control the flow of power to – essentially turn on or off – electronic devices. To design the GaN power switch, the IISc team used a metal organic chemical vapour deposition technique developed and optimised over a decade by researchers in the lab of Srinivasan Raghavan, Professor and Chair, CeNSE. It involves growing GaN alloy crystals layer by layer on a two-inch silicon wafer to fabricate a multi-layered transistor.
The entire process needs to be carried out carefully in a clean room to ensure that no defects arise due to environmental conditions like humidity or temperature, which can affect device performance. The team also took the help of Kaushik Basu, Associate Professor in the Department of Electrical Engineering (EE), and his lab, to build an electrical circuit using these transistors and test their switching performance.
GaN transistors typically operate in what is called a “depletion mode” – they are on all the time unless a negative voltage is applied to turn them off. But power switches used in chargers and adapters need to work the other way around – they normally need to be off and not carrying current, and should only turn on when a positive voltage is applied (“enhancement mode”). To achieve this operation, the team combined the GaN transistor with a commercially available silicon transistor to keep the device normally off.
“The packaging of the device was also indigenously developed,” explains Rijo Baby, PhD student at CeNSE and first author of the study. After packaging and testing, the team found the device performance to be comparable to state-of-the-art switches available commercially, with a switching time of about 50 nanoseconds between on and off operations.
Going forward, the researchers plan on scaling up the device dimensions so that it can operate at high currents. They also plan to design a power converter that can step up or step down voltages.
“If you look at strategic organisations in India, they have a hard time procuring GaN transistors … It is impossible to import them beyond a certain quantity or power/frequency rating,” says Nath. “This is essentially a demonstration of indigenous GaN technology development.”
Original – Indian Institute of Science (IISc)
-
Innoscience Technology has shipped more than 300 million pieces of its InnoGan gallium nitride chips as of August 2023, helping customers achieve small size, high energy efficiency, and low loss product design.
This is in response to phenomenal market demand across multiple sectors multiple applications in the consumer category – fast charging, mobile phones, LEDs – as well as automotive LIDAR, data centres, and renewable energy and energy storage systems, which has seen analysts such as TrendForce’s in its 2023 GaN Power Semiconductor Market Analysis Report, state that “the global GaN power device market will grow from US$180 million in 2022 to US$1.33 billion in 2026, with compound growth rate of 65%”.
In November 2017, Innoscience began the world’s first 8-inch GaN-on-Si mass production line, adopting the Integrated Device Manufacturer (IDM) whole industry chain model, and launched its first low-voltage GaN power device in May 2018. By June 2019, Innoscience’s 650V high-voltage GaN device had passed JEDEC approval, and subsequently, Innoscience has been the only semiconductor company in the world that simultaneously mass-produces high-voltage and low-voltage GaN.
Market acceptance of Innoscience’s high quality, high performance GaN devices has been swift. Following its 2019 entry into the fast charging market, Innoscience’s 650V parts have been adopted in 30W-120W designs by leading brands including ASUS, Anker, Nubia, Baseus, Greenlink, and Flash.
In 2020, Innoscience’s 100V low-voltage GaN was successfully used by Hesai in mass-production LIDAR designs, allowing lasers to achieve image transmission in a shorter time.
In March 2021, the Tencent×Nubia Red Magic mobile phone 6Pro was released. It comes equipped as standard with industry’s first 120W Black Rubik’s Cube GaN fast charge, which is based on Innoscience’s 650V chip. With the successive adoption by Oppo, Vivo, Lenovo and other manufacturers, it has become an industry trend for mobile phones to be equipped with GaN fast charging as standard.
March 2021 saw the mass-production of Innoscience’s bi-directional conduction chip V-GaN officially begin; this device is the only GaN chip in the world that can be applied to high-voltage side load switches, smartphone USB/wireless charging ports with built-in OVP protection, multi-power supply system switch circuits, and other scenarios:one V-GaN replaces two Si MOSFETs in load switching applications resulting in a smaller and more efficient solution.
In October of the same year, Innoscience scored another industry first, as OPPO used the company’s self-developed bi-directional conduction VGaN IC as the internal power switch in its latest smart phone. Other mobile phone makers such as Realme, OnePlus, Lenovo, and Motorola have also successively adopted VGaN for charging protection.
In May 2022, Shounuo released the world’s smallest 45W/65W PD car charger, using Innoscience’s 40V low-voltage INN040FQ043A.
Then in July, Anker and Innoscience jointly released the world’s first 65W full-GaN fast charger. This design uses GaN power chips at both the AC and DC ends for the first time, taking system power density and efficiency to a whole new level.
Later, in October 2022, Innoscience achieved mass production of GaN products targeting industrial power supplies – again an industry first – comprehensively improving energy conversion efficiency and reducing system energy consumption.
In November 2022, Innoscience’s INN100W032A won the IIC World Electronics Achievement Award. The gate charge of this product is only 20% of a traditional silicon MOSFET, and its Ciss is only 40% of its silicon counterpart. It can be widely applied in motor drive, Class D, data centre, motor-driver, communication base station and other product fields. In January 2023, Innoscience launched the SolidGaN ISG3201, a 100V highly-integrated half-bridge drive packaged solution, further improving the overall system performance of 48V power supply of data centre module power supplies, motor drives, class D power amplifiers, photovoltaic inverters and light hybrid electric vehicles.
The move to GaN as the premium power semiconductor technology is driven both by new GaN products and market demands. As an example, in April this year, Innoscience’s IATF 16949 automotive-grade low-voltage parts successfully expanded from industrial to automotive applications, with use in autonomous vehicle LIDAR systems.
Then in July 2023, Innoscience began to apply GaN in the field of renewable energy, reducing the size and improving the efficiency of photovoltaic modules.
By the end of August 2023, Innoscience had successfully mass-produced 54 different types of high-voltage GaN chips (650V-700V) and 20 types of medium-low voltage GaN chips (30V-150V). Products span three chip categories: wafers, discrete devices and integrated solutions.
Commented Dr Denis Marcon, Innoscience’s General Manager, Europe: “We are just at the start of the GaN story. The first applications were all in consumer, but GaN is undoubtedly the key to reducing costs and increasing efficiency in the industrial field as well. And according to automotive industry forecasts, GaN may enter automotive market already this year penetrating applications such as low-power OBC and DC-DC applications in 2025.
With such rapid growth in market demand, the reliability of devices, price competitiveness and stable supply in large quantities are now the major concerns of users. Based on an advanced Innoscience’s 8-inch GaN-on-Si IDM manufacturing platform, Innoscience’s current production capacity has reached 15,000 wafers per month, providing tremendous advantages in scale, reliability and cost.”
Original – Innoscience Technology
-
IQE plc, the leading supplier of compound semiconductor wafer products and advanced material solutions to the global semiconductor industry, announced a strategic collaboration with VisIC Technologies, a global leader in the provision of GaN (Gallium Nitride) power solutions to the automotive sector, to develop the highest reliability gallium nitride D-Mode (D-Mode GaN) power products for use in electric vehicles inverters.
IQE and VisIC Technologies will collaborate to develop 200mm (8”) D-Mode GaN power epiwafers that will be developed at IQE’s UK facilities, leveraging IQE’s well-established expertise in GaN technology.
VisIC Technologies, with its ground-breaking D3GaN technology (Direct Drive D-Mode GaN), brings the future of EV inverters into focus. This technology promises to reduce power consumption, increase reliability and enhance performance in electric vehicles. By combining VisIC Technologies’ innovative Power Electronics solutions with IQE’s epitaxy excellence, this partnership aims to accelerate the adoption of GaN-on-Silicon technology in EVs, significantly contributing to the evolution of sustainable transportation.
The collaboration marks another important milestone in IQE’s strategy of diversification into the high-growth Power market, first announced at its 2022 Capital Markets Day. IQE sees significant opportunities in the GaN Power epiwafer market in particular, which is forecast to reach a $632m value by 2027.
Original – VisIC Technologies
-
Navitas Semiconductor announced the world-wide launch of GaNSafe™, a new, high-performance wide bandgap power platform at a special customer, partner and press event in Taiwan. Navitas has optimized its 4th-generation gallium nitride technology for demanding, high-power applications in data centers, solar / energy storage and EV markets, where efficiency, power density and robust & reliable operation are critical.
At the worldwide launch event at the Marriot Taipei, Navitas’ David Carroll, Sr. VP Worldwide Sales, and Charles Bailley, Sr. Director Business Development will introduce Navitas and the new GaNSafe platform to an invited VIP audience of over 50 high-ranking customer attendees, plus industry partners and international media.
The new 4th-generation GaN power ICs are manufactured in Hsinchu, by long-term Navitas partner TSMC. Navitas is grateful to Dr. RY Su, Manager of GaN Power Technology at TSMC, who will make a special presentation on the future of GaN at the GaNSafe launch.
Navitas’ GaNFast™ power ICs integrate gallium nitride (GaN) power and drive, with control, sensing, and protection to enable faster charging, higher power density, and greater energy savings, with over 100,000,000 units shipped, and an industry-first 20-year warranty. Now, the new GaNSafe platformhas been engineered with additional, application-specific protection features, functions and new, high-power packaging to deliver enabling performance under grueling high-temperature, long-duration conditions.
The initial, high-power 650/800 V GaNSafe portfolio covers a range of RDS(ON) from 35 to 98 mΩ in a novel, robust, and cool-running surface-mount TOLL package, to address applications from 1,000 to 22,000 W. GaNSafe integrated features and functions include:
- Protected, regulated, integrated gate-drive control, with zero gate-source loop inductance for reliable high-speed 2 MHz switching capability to maximize application power density.
- High-speed short-circuit protection, with autonomous ‘detect and protect’ within 50 ns – 4x faster than competing discrete solutions.
- Electrostatic discharge (ESD) protection of 2 kV, compared to zero for discrete GaN transistors.
- 650 V continuous, and 800 V transient voltage capability to aid survival during extraordinary application conditions.
- Easy-to-use, complete, high-power, high-reliability, high-performance power IC with only 4 pins, to accelerate customer designs.
- Programmable turn-on and turn-off speeds (dV/dt) to simplify EMI regulatory requirements.
Unlike discrete GaN transistor designs, with voltage spikes, undershoot and specification breaches, GaNSafe delivers an efficient, predictable, reliable system. GaNSafe’s robust 4-pin TOLL package has achieved the tough IPC-9701 mechanical reliability standard, and delivers simple, strong, dependable performance as compared to multi-chip modules which require 3x as many connections, and have poor cooling capability.
Navitas’ market-specific system design centers offer complete platform designs with benchmark efficiency, density and system cost using GaNSafe products to accelerate customer time-to-revenue and maximize chance of first-time-right designs. These system platforms include complete design collateral with fully-tested hardware, embedded software, schematics, bill-of-materials, layout, simulation and hardware test results. Examples of system platforms enabled by GaNSafe technology include:
- Navitas’ CRPS185 data center power platform, that delivers a full 3,200 W of power in only 1U (40 mm) x 73.5mm x 185 mm (544 cc), achieving 5.9 W/cc, or almost 100 W/in3 power density. This is a 40% size reduction vs, the equivalent legacy silicon approach and reaches over 96.5% efficiency at 30% load, and over 96% stretching from 20% to 60% load, creating a ‘Titanium Plus’ benchmark.
- Navitas’ 6.6 kW 3-in-1 bi-directional EV on-board charger (OBC) with 3 kW DC-DC. This 96%+ efficient unit has over 50% higher power density, and with efficiency over 95%, delivers up to 16% energy savings as compared to competing solutions.
“Our original GaNFast and GaNSense technologies have set the industry standard for mobile charging, establishing the first market with high-volume, mainstream GaN adoption to displace silicon,” said Gene Sheridan, CEO and co-founder. “GaNSafe takes our technology to the next level, as the most protected, reliable and safe GaN devices in the industry, and now also targeting 1-22 kW power systems in AI-based data centers, EV, solar and energy storage systems. Customers can now achieve the full potential of GaN in these multi-billion dollar markets demanding the highest efficiency, density and reliability.”
The GaNSafe portfolio is available immediately to qualified customers with mass production expected to begin in Q4 2023. 40 customer projects are already in progress with GaNSafe in data center, solar, energy storage and EV applications, contributing to Navitas’ $1 billion customer pipeline.
Original – Navitas Semiconductor
-
Shin-Etsu Chemical Co., Ltd. has determined that QST® (Qromis Substrate Technology) substrate is an essential material for the social implementation of high-performance, energy-efficient GaN (gallium nitride) power devices, and the company will promote the development and launching on the market of these products.
Since QST® substrate is designed to have the same coefficient of thermal expansion (CTE) as GaN, it enables suppression of warpage and cracking of the GaN epitaxial layer and resultant large-diameter, high-quality thick GaN epitaxial growth. Taking advantage of these characteristics, it is expected to be applied to power devices and RF devices (5G and beyond 5G), which have been rapidly growing in recent years, as well as in such areas as MicroLED growth for MicroLED displays.
In addition to sales of QST® substrates, Shin-Etsu Chemical will also sell GaN grown QST® substrates upon customer request. We currently have a line-up of 6″ and 8″ diameter substrates, and we are working on 12″ diameter substrates. Since 2021, for each respective application for power devices, RF devices and LEDs, sample evaluation and device development are continuing with numerous customers in Japan and globally. Especially for power devices, continuous evaluation is underway for devices in the wide range of 650V to 1800V.
So far, Shin-Etsu Chemical has repeatedly made many improvements with regard to its QST® substrates. One example is the significant improvement in lowering defects originating from the bonding process, which has enabled the supply of high-quality QST® substrates. In addition, for the thicker GaN films that many of our customers have requested, we have promoted the provision of template substrates with optimized buffer layers, which enables our customers to realize stable epitaxial growth of more than 10 μm thickness. Furthermore, various successful results have been produced and reported on, including the achievement of thick-film GaN growth exceeding 20 μm using QST® substrates and the achievement of 1800V breakdown voltage in power devices.
Moreover, Shin-Etsu Chemical and Oki Electric Industry Co., Ltd. have jointly succeeded in developing a technology to exfoliate GaN from QST® substrates and bond it to substrates made of different materials using Crystal Film Bonding (CFB) technology. Until now, most GaN power devices have been lateral devices, but CFB technology takes advantage of the characteristics of QST® substrates to realize vertical power devices that can control large currents by exfoliating a thick layer of high-quality GaN from an insulating QST® substrate (see figure below).
To customers who manufacture GaN devices, Shin-Etsu Chemical will provide QST® substrates or GaN grown QST® substrates and Oki Electric Industry will provide its CFB technology through partnering or licensing. In this way, the two companies hope to contribute to the advancement of vertical power devices.
Based on these development results and also based on business situation inquiries from customers, Shin-Etsu Chemical will continue to increase production to meet customer demand.
Shin-Etsu Chemical will contribute to the realization of a sustainable society that can use energy efficiently by further promoting the social implementation of GaN devices that have characteristics that are absolutely essential for the future society.
Original – Shin-Etsu Chemical
-
EPC Space announced the introduction of two new rad-hard GaN transistors with ultra-low on-resistance and high current capability for high power density solutions that are lower cost and more efficient than the nearest comparable radiation-hardened silicon MOSFET. These devices come packaged in hermetic packages in very small footprints.
The EPC7020G is a 200 V, 14.5 mΩ, 200 Apulsed radiation-hardened gallium nitride transistor and the EPC7030G is a 300 V, 32 mΩ, 200 Apulsed radiation-hardened gallium nitride transistor. These devices join the 40 V, 4.5 mΩ EPC7019G and the 100 V, 4.5 mΩ EPC7018G to cover applications including power supplies for satellites and space mission equipment, motor drives for robotics, instrumentation and reaction wheels, and deep space probes. This product family comes packaged in a compact hermetic package in a footprint less than 45 mm2.
Part Number Drain to Source Voltage (VDS) Drain to Source Resistance (RDS(on)) Single-Pulse Drain Current (IDM) EPC7019G 40 V 4 mΩ 530 A EPC7018G 100 V 6 mΩ 345 A EPC7020G 200 V 14.5 mΩ 200 A EPC7030G 300 V 32 mΩ 200 A With higher breakdown strength, lower gate charge, lower switching losses, better thermal conductivity, and lower on-resistance, power devices based on GaN significantly outperform silicon-based devices and enable higher switching frequencies resulting in higher power densities, higher efficiencies, and more compact and lighter weight circuitry for critical spaceborne missions.
“The G-Package family offers the lowest on-resistance of any packaged rad hard transistor currently on the market,” said Bel Lazar, CEO of EPC Space. “These devices offer mission-critical components with superior figure of merit, significantly smaller size, and lower cost for the space and other high-reliability markets than alternative rad hard silicon solutions”.
Original – EPC Space
-
Navitas Semiconductor will reveal a new, high-performance wide bandgap power platform as part of its display at one of Asia’s most prestigious electronics exhibitions – sponsored by Navitas – SEMICON Taiwan 2023, from September 6th-8th.
Visitors will discover the latest gallium nitride (GaN) GaNFast™ power ICs integrate gallium nitride (GaN) power and drive, with control, sensing, and protection to enable faster charging, higher power density, and greater energy savings. Complementary GeneSiC™ power devices are optimized high-power, high-voltage, and high-reliability silicon carbide (SiC) solutions.
Additionally, Navitas will showcase cutting-edge, power-system platforms to dramatically accelerate customer developments, minimize time-to-market, and set new industry benchmarks in energy efficiency, power density and system cost. These system platforms include complete design collateral with fully-tested hardware, embedded software, schematics, bill-of-materials, layout, simulation and hardware test results. Examples include:
- Navitas’ CRPS185 data center power platform, that delivers a full 3,200 W of power in only 1U (40 mm) x 73.5mm x 185 mm (544 cc), achieving 5.9 W/cc, or almost 100 W/in3 power density. This is a 40% size reduction vs, the equivalent legacy silicon approach and reaches over 96.5% efficiency at 30% load, and over 96% stretching from 20% to 60% load, creating a ‘Titanium Plus’ benchmark.
- Navitas’ 6.6 kW 3-in-1 bi-directional EV on-board charger (OBC) with 3 kW DC-DC. This 96%+ efficient unit has over 50% higher power density, and with efficiency over 95%, delivers up to 16% energy savings as compared to competing solutions.
As part of SEMICON’s Power and Opto Semiconductor Forum, Navitas’ Charles Bailley, Senior Director of Business Development, will present “GaN Power ICs Increase Power Density in EV Power Systems”. The presentation is at 2pm, on September 6th, in room 402, 4F, TaiNEX 1.
“Breakthrough high efficiency, high reliability, and high power density – all from the new GaN power IC platform,” said Kevin 汪時民 Wang, Manager of Navitas Taiwan. “The new platform announcement matches SEMICON’s theme of ‘Innovating the World through Semiconductors’ and our own mission to ‘Electrify Our World™’.”
Original – Navitas Semiconductor
-
Transphorm, Inc. announced that its GaN platform powers the world’s first integrated photovoltaic (PV) systems from DAH Solar Co., Ltd. (Anhui Daheng New Energy Technology Co., LTD/subsidiary of DAH Solar). The PV systems are used in DAH Solar’s new SolarUnit product line. DAH Solar credits Transphorm’s GaN FETs with enabling it to produce smaller, lighter, and more reliable solar panel systems that also offer higher overall power generation with lower energy consumption.
The design achievements continue to demonstrate Transphorm’s One Core GaN Platform, Crossing the Power Spectrum leadership position by solidifying its value proposition in the renewables market, which currently represent a GaN TAM of more than $500M.
DAH Solar uses Transphorm’s 150 mΩ and 70 mΩ GaN FETs in the SolarUnits’ design architecture (both DC-to-DC and DC-to-AC power stages). The SolarUnits are available in three models with power outputs of 800 W, 920 W, or 1500 W and peak efficiencies of 97.16%, 97.2%, and 97.55% respectively. The GaN devices deliver higher switching frequencies and power density versus incumbent silicon solutions. Notably, the two FETs are available in PQFN88 performance packages that pair with commonly-used gate drivers—features that helped DAH Solar quicken its design time.
“We have a strong legacy of producing innovative PV products. As such, we consistently look for ways to advance our products with state-of-the-art technologies to create a better, more efficient end user experience,” said Yong Gu, GM, DAH Solar. “We view Transphorm as an authority in the field of GaN production and found their advanced GaN FETs to be the optimal devices for our new SolarUnit line. The devices are easy to design in and offer performance advantages that enable us to continue building on our legacy.”
Transphorm today supports the largest range of power conversion requirements (45 W to 10+ kW) across the widest range of power applications. The company’s FET portfolio includes 650 V and 900 V devices with 1200 V devices in development. These FETs are JEDEC and AEC-Q101 qualified, making them optimal solutions for power adapters and computer PSUs through to broad industrial UPSs and electric vehicle mobility systems.
The company’s technology innovations continue to set new benchmarks across the GaN power semiconductor industry. In parallel, they help customers bring to market new, disruptive applications in their own markets—such as DAH Solar’s PV systems.
These achievements are due to Transphorm’s normally-off SuperGaN® platform, which uses the cascode d-mode configuration to harness GaN’s intrinsic advantages. The superior physics of this high performance GaN platform design delivers competitively unmatched benefits such as easier drivability, easier designability, higher reliability, and greater manufacturability.
“The value Transphorm’s GaN platform brings to a variety of applications continues to be demonstrated by market leaders like DAH Solar,” Kenny Yim, Vice President of Asia Sales, Transphorm. “Solar inverters as well as other high-power applications require highly reliable, high performing power semiconductors that can withstand decades of operation in harsh environments.
Using Transphorm’s SuperGaN technology helps reduce power loss thereby minimizing thermal stress on other designed-in components. That’s a phenomenal achievement over alternative GaN and Silicon solutions underscoring the benefits our GaN brings to next generation power systems.”
Original – Transphorm
-
MACOM Technology Solutions Holdings, Inc. announced that it has entered into a definitive agreement to acquire the radio frequency business of Wolfspeed, Inc. The RF Business includes a portfolio of Gallium Nitride (“GaN”) on Silicon Carbide (“SiC”) products used in high performance RF and microwave applications.
The business services a broad customer base of leading aerospace, defense, industrial and telecommunications customers and most recently generated annualized revenues of approximately $150 million. The acquisition is expected to be immediately accretive to MACOM’s non-GAAP earnings.
“We are excited to acquire Wolfspeed’s RF Business and look forward to welcoming its employees to MACOM,” stated Stephen G. Daly, President and Chief Executive Officer, MACOM. “The RF team’s engineering capabilities, technology and products are a perfect fit with MACOM and our strategy.”
The acquisition includes a 100mm GaN wafer fabrication facility in Research Triangle Park, North Carolina (the “RTP Fab”) with operations conveying to MACOM approximately two years following the closing and Wolfspeed’s relocation of certain production equipment.
The acquisition also includes design teams and associated product development assets in Arizona, California and North Carolina, as well as back-end production capabilities in California and Malaysia. In addition, MACOM will be assigned or licensed a robust intellectual property portfolio including over 1,400 patents associated with the RF Business.
The RF Business will be acquired for $125 million, including $75 million cash paid at closing and $50 million of MACOM common stock issued with certain restrictions. A workforce of approximately 280 employees is expected to join MACOM at closing, with additional employees joining when the RTP Fab conveys.
Closing of the transaction is subject to the expiration of a waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 and other closing conditions and is expected to occur in the second half of calendar year 2023.
Original – MACOM Technology Solutions
-
Transphorm, Inc. announced it has demonstrated up to 5 microsecond short circuit withstand time (SCWT) on a GaN power transistor with a patented technology. The achievement is the first of its kind on record, marking an important milestone for the industry as a whole. It proves Transphorm GaN’s ability to meet the required short circuit capabilities of rugged power inverters such as servo motors, industrial motors, and automotive powertrains served traditionally by silicon IGBTs or silicon carbide (SiC) MOSFETs— an over $3 billion GaN TAM over the next 5 years.
The demonstration was developed with support from Yaskawa Electric Corporation, a long-term strategic partner of Transphorm’s and a global leader in low and medium voltage drives, servo systems, machine controllers, and industrial robots. This makes GaN a highly attractive power conversion technology for servo systems, as it allows for higher efficiency and reduced size compared to incumbent solutions.
To do that, GaN must pass stringent robustness tests—of which, short-circuit survivability is the most challenging. In case of short-circuit faults, the device must survive extreme conditions with both high current and high voltage. The system can take up to a few microseconds to detect the fault and shut down the operations. During this time, the device must withstand the fault on its own.
“If a power semiconductor device cannot survive short-circuit events, the system itself may fail. There was a strong perception that GaN power transistors could not meet the short circuit requirements needed for heavy-duty power applications such as ours,” said Motoshige Maeda, Department Manager of Fundamental R&D Management Department, Corporate Technology Division, Yaskawa. “Having worked with Transphorm for many years, we believed that perception to be unfounded and have been proven right today. We’re excited about what their team has accomplished and look forward to demonstrating how this new GaN feature can benefit our designs.”
The short-circuit technology has been demonstrated on a newly designed 15 mΩ 650 V GaN device. Notably, that device reaches a peak efficiency of 99.2% and a maximum power of 12 kW in hard-switching conditions at 50 kHz. The device demonstrated not only performance, but also reliability, passing high-temperature high-voltage stress requirements.
“Standard GaN devices can withstand short-circuit for only a few hundredths of nanoseconds, which is too short for fault detection and safe shut-down. However, with our cascode architecture and key patented technology, we were able to demonstrate short-circuit withstand time up to 5 microseconds with no additional external components, thus retaining low cost and high performance,” said Umesh Mishra, CTO and Co-Founder, Transphorm.
“We understand the demands of high-power, high-performance inverter systems. We have a long history of strong innovation, and we’re proud to say that experience helped us bring GaN to the next level. This is yet another validation of Transphorm’s global leadership in high voltage GaN robustness and reliability and will be a gamechanger for GaN in motor drives and other high-power systems.”
The full description explaining the SCWT achievement, the demonstration analysis, and more is expected to be presented at a major power electronics conference next year.
Original – Transphorm
