GaN FET USB-C power adapter reference design boasts 30 W/in3 power density

Transphorm, Inc. announced a world-class GaN power adapter reference design. The solution is an open frame, 65W USB-C Power Delivery (PD) charger that combines Transphorm’s SuperGaN Gen IV platform with Silanna Semiconductor’s proprietary Active Clamp Flyback (ACF) PWM controller. Together, the technologies yield an unprecedented peak efficiency of 94.5 percent with an uncased power density of 30W/in3. These performance levels outpace the currently available competing solutions using silicon super-junction MOSFETs or e-mode GaN transistors, and furthermore utilize a smaller GaN FET from Transphorm. Silanna Semiconductor and Transphorm’s universal GaN adapter design is ideal for powering laptops, tablets, smartphones, and other IoT devices.

The new reference design relies on advanced technologies from both Transphorm and Silanna Semiconductor. The SuperGaN FET is Transphorm’s TP65H300G4LSG, a 650 V 240 mΩ device in an industry-standard PQFN88 package. It leverages the SuperGaN Gen IV platform, which uses advanced epi and patented design technologies to improve performance. The robust GaN FET also offers the high reliability synonymous with Transphorm devices, including the industry’s best gate robustness. And, unlike e-mode devices, protective external circuitry such as additional bias rails or level shifters are not needed—an advantage that produces higher efficiency. Collectively, these and other features further increase the adapter system’s overall power density and reduce BoM costs.

Silanna semiconductors SZ1130 is the world’s first fully-integrated ACF PWM controller that integrates an adaptive digital PWM controller, an Active Clamp FET, an Active Clamp Gate Driver, and a UHV Startup regulator. As an ACF solution, it delivers higher performance than competing quasi-resonant (QR) controllers and offers the simplest design in the smallest PCB area among all ACF controllers in the market. Silanna Semiconductor’s technology-agnostic design focuses on the ultimate power management challenges with the best-in-class power density and efficiency that delight customers with unprecedented BoM savings.

The 65W USB-C PD GaN power adapter reference design’s schematic, design files, and bill of materials are available from both manufacturers under the respective names below.