STMicroelectronics extends MasterGaN family for asymmetrical topologies

Building upon the advantages of STMicroelectronics’ MasterGaN platform, MasterGaN2 is the first in the new family to contain two asymmetric gallium-nitride (GaN) transistors — delivering an integrated GaN solution suited to soft-switching and active-rectification converter topologies.

The 650V normally-off GaN transistors have on-resistance (RDS(on)) of 150mΩ and 225mΩ. Each is combined with an optimized gate driver, making GaN technology as easy to use as ordinary silicon devices. By combining advanced integration with GaN’s inherent performance advantages, MasterGaN2 further extends the efficiency gains, size reduction, and weight savings of topologies such as active clamp flyback.

The MasterGaN power system-in-package (SiP) family combines the two GaN High-Electron-Mobility Transistors (HEMTs) and associated high-voltage gate drivers in the same package with all necessary protection mechanisms built-in. The designer can easily connect external devices including Hall sensors and a controller such as a DSP, FPGA, or microcontroller directly to the MasterGaN device.

The inputs are compatible with logic signals from 3.3 to 15V, which helps simplify the circuit design and bill of materials, permits a smaller footprint, and streamlines assembly. This integration helps raise the power density of adapters and fast chargers.

GaN technology is driving the evolution toward fast USB-PD adapters and smartphone chargers. ST’s MasterGaN devices enable these to become up to 80% smaller and 70% lighter while charging three times faster than ordinary silicon-based solutions.

The built-in protection comprises low-side and high-side under-voltage lockout (UVLO), gate-driver interlocks, a dedicated shutdown pin, and over-temperature protection. The 9 x 9 x 1mm GQFN package is optimized for high-voltage applications, having over 2mm creepage distance between high-voltage and low-voltage pads.