GaN power adapter reference design

The design is for an open frame, 65W USB-C Power Delivery (PD) charger that combines Transphorm’s SuperGaN Gen IV platform with Silanna Semiconductor’s  Active Clamp Flyback (ACF) PWM controller.

Together, the technologies yield a peak efficiency of 94.5 percent with an uncased power density of 30W/in3.

The SuperGaN FET is Transphorm’s TP65H300G4LSG, a 650 V 240 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.

Unlike e-mode devices, protective external circuitry such as additional bias rails or level shifters are not needed—an advantage that produces higher efficiency. 

Silanna Semiconductor‘s SZ1130  ACF PWM controller  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.

Silanna Semiconductor: RD-19 (contact Transphorm: TDADP-SIL-USBC-65W-RD (download the files here)