New Industry Products

1.7kV SiC FET for Inverter Auxiliary Power Supplies

October 04, 2015 by Jeff Shepard

Wolfspeed, a Cree Company, has introduced the first 1700V SiC MOSFET offered in an optimized surface mount package designed for commercial use in auxiliary power supplies in high-voltage power inverter systems. The higher blocking voltage enables design engineers to replace lower rated silicon MOSFETs with the new SiC MOSFETs, delivering higher efficiency, simplified driver circuitry, and lower thermal dissipation, and resulting in lower total system costs.

The new SMD package, specifically designed for high voltage MOSFETs, has a small footprint with a wide creepage distance: 7mm between drain and source. This is made possible by the small die size and high blocking capability of Wolfspeedâ„¢ SiC planar MOS technology. The new package also includes a separate driver source connection, which reduces gate ringing and provides clean gate signals.

“Our new 1700V SiC MOSFET provides power electronics engineers with significant design advantages, particularly in flyback topologies,” explains Edgar Ayerbe, Wolfspeed marketing manager for power MOSFETs. “Due to the lower switching losses of silicon carbide, the devices operate at much lower junction temperatures. This enables customers to directly mount the devices onto the PCB with no additional heat sinks, which greatly reduces the manufacturing costs and improves the reliability of the systems. The result is a smaller, lighter power supply with a lower system cost than is possible using silicon devices.”

Application of the new 1700V SiC MOSFET is anticipated in auxiliary power supplies within high power inverters — such as solar power inverters, motor drives, UPS equipment, wind-energy converters, and traction power systems — which typically buck down dc voltages to operate system logic, protection circuitry, displays, network interface, and cooling fans. They can also be used in the power supplies of three-phase e-meters, or in any converter application that requires high blocking voltages and low capacitance.

Designated the C2M1000170J, the new 1700V SiC MOSFET features an avalanche rating greater than 1800V, and RDS(on) of 1Ω. These characteristics ensure reliable performance in flyback converter circuits, including those in noisy electrical environments, such as those found in high-power inverters. By enabling the design of single-switch flyback topologies from input voltages spanning 200V to 1000V, the 1700V SiC MOSFET simplifies the complex drive and snubber circuit elements required for silicon devices. The C2M1000170J is fully qualified and available for immediate sampling.