Wolfspeed introduced a 1,000-V MOSFET that the
company says enables a reduction in overall system cost, while improving system
efficiency and decreasing system size. It’s optimized for fast charging and
industrial power supplies, enables a 30% reduction in component count while
achieving more than 3x increase in power density and a 33% increase in output
power.

 

 

 

cspo04_Wolfspeed_1000VSiC_nov2016

 

The electric vehicle market needs, and is
always looking for, higher efficiency and wider output voltage ranges especially
for all the electric vehicle battery voltages being introduced by automotive
suppliers. This will no doubt enable smaller, more efficient charging systems
that have higher power charging, and probably have lower overall cost.

 

The 1,000-V, 65-mΩ MOSFET is available in a
through-hole, 4L-TO247 package, is listed as part number C3M0065100K, and is currently
available for purchase at Digikey, Mouser, and Richardson RFPD. The package has
a Kelvin-source connection. The surface mount versions of these devices,
C3M0065100J and C3M0120100J, will be released later this year. Like the
4L-TO247, the surface mount devices include a Kelvin-source pin to help
minimize gate ringing and reduce system losses. Download the
datasheet
.

 

These SiC MOSFETs offer fast switching speeds
with much lower switching loses than silicon MOSFETs. The figure-of-merit is
also better than silicon-based MOSFETs. The SiC MOSFET also enables designers to
reduce component count by moving from silicon-based, three-level topologies to
simpler two-level topologies made possible by the 1000 Vds rating of
the SiC MOSFET. The output capacitance is as low as 60pF, which significantly
lowers switching losses. This device enables operations at higher switching
frequencies, which shrinks the size of the resonant tank elements and decreases
overall losses, thus reducing heatsink requirements. 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 20-kW full-bridge resonant
LLC converter reference design, listed as part number CRD-20DD09P-2. This fully
assembled hardware set allows designers to evaluate the new 1000-V SiC MOSFET.

 

The LLC converter’s
reference design files, which include full schematics, bill of materials,
simulation files, and a detailed user guide, can be found online at go.wolfspeed.com/referencedesigns.