14 September 2021
UnitedSiC expands 750V SiC FET range, including 6mΩ option
Silicon carbide (SiC) power semiconductor maker United Silicon Carbide Inc (UnitedSiC) of Princeton, NJ, USA says that it has responded to power designers’ requests for higher-performance, higher-efficiency SiC field-effect transistors (FETs) by announcing a 750V, 6mΩ device. At an on-resistance RDS(on) value of less than half the nearest SiC MOSFET competitor, the new 6mΩ device also provides a robust short-circuit withstand time rating of 5μs.
The launch includes nine new device/package options in the 750V SiC FET series, rated at 6, 9, 11, 23, 33 and 44mΩ. All devices are available in the TO-247-4L package, while the 18, 23, 33, 44 and 60mΩ devices also come in the TO-247-3L package. Complemented by the already available 18 and 60mΩ devices, this 750V expanded series provides designers with more device options, enabling more design flexibility to achieve an optimum cost/efficiency trade-off while maintaining generous design margins and circuit robustness, says the firm.
UnitedSiC’s Gen 4 SiC FETs are a ‘cascode’ of a SiC JFET and a co-packaged silicon MOSFET. Together, these provide the full advantages of wide-bandgap technology: high speed and low losses with high-temperature operation, while retaining an easy, stable and robust gate drive with integral ESD protection.
These advantages are quantified by figures of merit (FoMs) such as RDS(on) x A, a measure of conduction losses per unit die area. Gen 4 SiC FETs achieve what are claimed to be the lowest values in the market at both high and low die temperatures. The FoM RDS(on) x EOSS/QOSS is important in hard-switching applications and is half the nearest competitor value, it is reckoned. The FoM RDS(on) x COSS(tr) is critical in soft-switching applications, and UnitedSiC claims that its device values are around 30% less than competitor parts, rated at 650V compared with UnitedSiC’s at 750V.
For hard-switching applications, the integral body diode of SiC FETs is superior in recovery speed and forward voltage drop to competing Si MOSFET or SiC MOSFET technologies. Other advantages incorporated into the Gen 4 technology are reduced thermal resistance from die to case by using advanced wafer thinning techniques and silver-sinter die-attach. These features enable maximum power output for low die temperature rise in demanding applications.
With their latest improvements in switching efficiency and on-resistance, the new SiC FETs are suitable for challenging emerging applications. These include traction drives and on- and off-board chargers in electric vehicles (EVs) and all stages of uni- and bi-directional power conversion in renewable energy inverters, power factor correction (PFC), telecoms converters, and AC/DC or DC/DC power conversion generally. Established applications also benefit from use of the devices for an easy boost in efficiency due to their backwards compatibility with silicon MOSFET and IGBT gate drives and established TO-247 packaging.
“The new range additions now provides further options for all performance and budget specifications, and a wider range of applications,” comments president & CEO Chris Dries.
Pricing (1000-up, FOB USA) for the new 750V Gen 4 SiC FETs range is from $4.15 for the UJ4C075044K3S to $23.46 for the UJ4SC075006K4S. All devices are available via authorized distributors.