STMicroelectronics has unveiled a new range of gallium nitride (GaN) flyback converters designed to simplify the development of compact, high-efficiency power supplies for USB-PD chargers, fast battery chargers, and auxiliary applications.
The new devices, beginning with the VIPerGaN50W, integrate a 700V GaN power transistor, a flyback controller, and an optimised gate driver within a single compact package. By combining these elements, ST aims to accelerate time to market, increase power density, and reduce component counts.
The converters operate in quasi-resonant mode with zero-voltage switching (ZVS) across the full load range, improving efficiency and minimising heat. At lighter loads, ST’s proprietary control techniques — including frequency foldback, valley skipping, and a so-called ‘valley lock’ mechanism — ensure the converters remain silent, eliminating audible noise often associated with switching variations.
When idle, the converters switch to a burst mode that lowers power consumption to below 30mW, allowing device makers to comply with increasingly strict eco-design standards.
Additional power management features stabilise output performance across fluctuating supply voltages. These include line-voltage feedforward, dynamic blanking time to reduce switching losses, and comprehensive protection functions such as overvoltage, thermal shutdown, and brown-in/brown-out safeguards.
ST has also introduced the EVLVIPGAN50WF evaluation board to support development. The board implements a 15V/50W isolated flyback converter with secondary-side synchronous rectification, enabling designers to test the VIPerGaN50W’s full feature set.
The VIPerGaN50W is already in production, supplied in a 5mm x 6mm Power QFN package. It is available through ST’s eSTore and authorised distributors, priced from $1.09 per unit for orders of 1,000 pieces.
