TT Electronics has introduced a line of GaN-ready magnetics, which the company defines as magnetics that are optimized for both performance and size in high-frequency switching applications — up to 500 kHz at powers up to 1 kW and up to 250 kHz at powers from 1 to 10 kW.
As the company explained in a press release, power is lost whenever electricity is converted from one form to another. In a magnetic device, eddy currents, the formation of circulating current loops within the core or shifts in the magnetic domains within the core material (also known as “hysteresis”) can result in core loss. Valuable electrical energy can also be converted into heat, creating a double loss.
But the use of new materials and technologies can significantly reduce that loss. There are dozens of possible choices for core material, among the most promising of which is gallium nitride (GaN). The material is compact, fast, light, cool-running and efficient, and is both replacing silicon and competing with silicon carbide (SiC) in various switching applications.
Compared to silicon, GaN has a higher electron saturation velocity — the maximum velocity that an electron reaches in an electric field — allowing it to outperform silicon at high frequency. It also has a high critical field, the highest magnetic field under which a material remains superconducting, that enables GaN-based devices to operate at low leak currents and high voltages. In the realm of high-frequency, high-voltage applications, GaN also has an edge over SiC in terms of electron mobility, or the speed with which an electron can move through it.
These advantages, however, can be lost if magnetics such as power factor correction inductors and transformers are not correctly designed for use with GaN switches — exactly what TT Electronics’ new line is intended to address.
For more information on the company’s custom design capabilities, visit the TT Electronics Design Center.
