Planar SiC MOSFET die targets drive trains

January 10, 2017 // By Nick Flaherty
Wolfspeed, part of Cree, has launched a 900V, 10mΩ planar silicon carbide (SiC) MOSFET that can reduce inverter losses in the drive train of electric vehicles by 78%. 

The CPM3-0900-0010A is rated for 196 A of continuous drain current at a case temperature of 25̊̊ºC. The efficiency improvement offers designers new options in terms of range, battery usage and vehicle design.

Recently Wolfspeed supplied Ford Motor Company―in a collaboration with the U.S. DoE―with a full-SiC, 400A power module designed around the 900V, 10mΩ chip. The module, designed and produced by Wolfspeed, contains four MOSFETs connected in parallel to achieve 2.5mΩ Rds(on). Wolfspeed engineers have since demonstrated the capability to use these chips to create an 800A, 1.25mΩ module.

Unlike silicon MOSFETs, the C3M SiC MOSFETs include a fast intrinsic diode with low reverse recovery (Qrr), eliminating the need for external anti-parallel diodes.  Unlike silicon IGBTs, they include avalanche capability and enable operation at higher switching frequencies, which shrinks the size of the resonant tank elements and decreases overall size, weight, and cost of the system.  

“With the commercial release of the 900V 10mΩ device, electric vehicles can now reap the benefits of SiC in all aspects of their power conversion,” said John Palmour, CTO of Wolfspeed. “With the continued expansion of our Gen3 MOSFET portfolio in new package options, our devices can now support significant efficiency improvements in onboard chargers, offboard chargers, and now EV drive trains.”

Commercially qualified and rated for a maximum operating temperature of 175˚C, the die offers high-reliability in harsh environments such as drive trains.

The 900V, 10mΩ CPM3-0900-0010A is available in bare die from SemiDice. Wolfspeed expects to release the associated discrete device in a 4L-TO247 package (C3M0010090K) in the coming weeks. This package has a Kelvin-source connection that allows engineers to create designs that maximize the benefits of SiC’s superior speed and efficiency.

More details are at the product page