Wolfspeed of Research Triangle Park, NC, USA — a Cree Company that makes silicon carbide (SiC) power products including MOSFETs, Schottky diodes, and modules — has introduced what it claims is the first 1000V MOSFET, which enables a reduction in overall system cost while improving system efficiency and decreasing system size. Specially optimized for fast charging and industrial power supplies, the new MOSFET enables a 30% reduction in component count while achieving more than a 3x increase in power density and a 33% increase in output power.
"Supporting the widespread implementation of off-board charging stations, Wolfspeed's technology enables smaller, more efficient charging systems that provide higher-power charging at lower overall cost," says chief technology officer John Palmour. "This market requires high efficiency and wide output voltage range to address the various electric vehicle (EV) battery voltages being introduced by automotive suppliers," he adds.
"Wolfspeed's new 1000V SiC MOSFET offers system designers ultra-fast switching speeds with a fraction of a silicon MOSFET's switching losses. The figure-of-merit delivered by this device is beyond the reach of any competing silicon-based MOSFET," Palmour reckons.
Designers can reduce component count by moving from silicon-based, three-level topologies to simpler two-level topologies made possible by the SiC MOSFET's 1000Vds rating. The increase in output power in a reduced footprint is realized by the ultra-low output capacitance (as low as 60pF), which significantly lowers switching losses. The new device enables operations at higher switching frequencies, which shrinks the size of the resonant tank elements and decreases overall losses, reducing heat-sink requirements, says the firm. Wolfspeed has determined these proof-points by constructing a 20kW full-bridge resonant LLC converter and comparing it to a market-leading 15kW silicon system.
Wolfspeed offers a 20kW full-bridge resonant LLC converter reference design (part number CRD-20DD09P-2). This fully assembled hardware set allows designers to quickly evaluate the new 1000V SiC MOSFET and demonstrate its faster switching capability, as well as the increased system power density that the device enables, says the firm.
The 1000V, 65mΩ MOSFET is available in a through-hole 4L-TO247 package (as part number C3M0065100K) and is available for purchase at Digikey, Mouser and Richardson RFPD.
Wolfspeed plans to release another 1000V MOSFET in a 4L-TO247 package at 120mΩ (C3M0120100K) 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.
Surface-mount versions of these devices (C3M0065100J and C3M0120100J) will be released later this year. Like the 4L-TO247, these will include a Kelvin-source pin to help minimize gate-ringing and reduce system losses.
