23 March 2022
Transphorm’s SuperGaN FETs power Boco’s crypto-mining power supply
Transphorm Inc of Goleta, near Santa Barbara, CA, USA — which designs and manufactures JEDEC- and AEC-Q101-qualified gallium nitride (GaN) field-effect transistors (FETs) for high-voltage power conversion — says that its SuperGaN FETs are being used in the new 3.6kW power supply of Hangzhou Boco Electronics Co Ltd. The 12V AC-to-DC power supply achieves a peak efficiency of greater than 96% and is designed to be used in rugged environments caused by ultra-demanding applications such as crypto-mining rigs and high-performance data-center systems. Driven by Transphorm’s SuperGaN devices in a patented bridgeless totem-pole power-factor correction (PFC) topology, that power efficiency rating is nearly 1% higher or 36W lower power consumption than what Boco Electronics achieves in traditional PFC configurations. The totem-pole PFC topology, along with the FET’s TO-247 package, also enables reduction of the overall power system’s component count, in turn reducing the overall system cost.
“Mining rigs run 24 hours a day, seven days a week. Given this, our customers seek higher-power, higher-efficiency, higher-reliability power supplies to support these intensive applications,” says Boco Electronics’ CEO Golden Yin. “We knew we could meet those requirements by matching our strong design capabilities with advanced GaN solutions,” he adds. “Whereas GaN was the right technology in general, Transphorm’s SuperGaN products were the right devices. They proved to be better suited for the higher power ranges while offering the higher field reliability required by such industrial applications when compared to alternative options.”
The Transphorm device used in the power supply is the JEDEC-qualified TP65H035G4WS, a normally-off 650V device with an on-resistance of 35mΩ. Part of the SuperGaN Gen IV product family, it offers what is claimed to be an industry-leading ±20V gate robustness with the industry’s best noise immunity threshold of 4V.
With faster switching and lower losses, Transphorm’s GaN replaces traditional MOSFETs used by Boco Electronics in similar incumbent power supplies. Further, it allows Boco to use the advanced totem-pole PFC in lieu of an interleaving H (full bridge) PFC or interleaving DCM PFC. The system’s resulting power density increased, allowing for additional space for increased cooling air flow. Notably, development of the power supply took only six months, aligning with the ease of drivability and designability that is synonymous with Transphorm’s devices.
“Power-hungry applications like crypto mining — which solve complex mathematical problems while processing massive amounts of data — are increasingly more expensive to support, from hardware to raw energy resources. In fact, mining farms that used to benefit from local government support and cheaper energy delivery through hydropower in China are now being forced to relocate, as a result of regulatory changes,” says Kenny Yim, Transphorm’s VP of Asia Pacific sales (citing Feng, Coco, ‘Chinese bitcoin miner exodus faces hurdles as equipment remains stuck from shipments delays, tariffs and legal quagmire’, South China Morning Post, 12 February). “As a result, we’re seeing manufacturers of related high-power application systems turn to GaN for remarkably better performance and efficiency to combat higher electricity prices. It’s a trend we’re proud to support as we continue to strengthen and enhance our GaN platform,” he adds.
Transphorm says that its role in Boco Electronics’ product development process went beyond supplying transistors. Its technical support team collaborated with the Boco’s engineering team on design reviews to ensure that the GaN technology was maximized for the highest performance output possible.