Wolfspeed launches fourth generation SiC technology ...

Wolfspeed has launched its fourth generation silicon carbide (SiC) technology platform for power applications.

The first two bare die in the 1200V CPM4 family for industrial applications have on resistance of 26mΩ with 90A and 42mΩ with 55mA. This is 20% lower at the same junction temperature of 175 °C. A bare die version for automotive, the EPM4, is undergoing qualification. micro semiconductor

Packaging is a key element in the on resistance, and the first E4M packaged part has a higher current of 153A with an on resistance reduced to 13mΩ from 16mΩ in a four lead TO-247 Kelvin package.

Wolfspeed does not seem to be looking at reducing the production cost of the devices but simplifying the design process with larger margins to speed up development times and reduce the cost of other components.

For example a short-circuit withstand time of up to 2.3 µs provides additional safety margin to reduce the cost of a design.

The fourth generation GM4 modules have a 1200V half-bridge topology with currents of 200A and on resistance as low as 4mΩ, with the 2300V variant on an ALN substrate having an RDS(on) as low as 5mΩ. The full bridge 1200V, 100A modules have an on resistance of 11mΩ.

In hard-switched applications, such as industrial motor drives, power supplies for AI data centres, and active front-end (AFE) converters for grid-connected systems, the reduction of switching losses is paramount. These applications operate at varying loads and sometimes run at very high power for short bursts, but they spend much of their lifetime at lower power levels.

From an efficiency perspective, minimizing conduction losses helps improve efficiency across the entire load range.

These conduction losses are driven primarily by the on-state resistance of the power MOSFET evaluated at the application’s required current levels and resulting junction temperature(s) At full rated load current, the MOSFETs are generally operating near their maximum rated operating temperature (or lower by some design margin) MOSFET part number selection and ultimately system semiconductor BOM cost is determined by this high temperature Rds(on).

Reduction of switching losses offers two primary advantages, says Dr. Adam Barkley, VP, Power Technology Development at Wolfspeed.

First, designers can increase switching frequency, enabling smaller, lighter, and more cost-effective magnetics and capacitors Or they can prioritize efficiency gains by reducing heat dissipation, lowering system-level costs through smaller heat sinks or reduced cooling requirements

Wolfspeed’s Gen4 MOSFETs reduce this high temperature specific on-state resistance by up to 21%, with even more reduction at lower temperatures, says Barkley.

“We understand that each application’s design comes with a unique set of requirements,” said Jay Cameron, senior vice president of Wolfspeed power products. “From its inception, our goal for Gen 4 has been to improve overall system efficiency in real-world operating environments, with a focus on delivering maximum performance at the system level. Gen 4 enables design engineers to create more efficient, longer-lasting systems that perform well in tough operating environments at a better overall system cost.”

Wolfspeed’s Gen 4 products are available in 750V, 1200V and 2300V nodes. New product introductions, including additional footprints and RDS ON ranges, will be available throughout 2025 and early 2026.