3 May 2010


SemiSouth launches 1700V and 1200V SiC JFETs

SemiSouth Laboratories Inc of Starkville, MS, USA, which designs and manufactures silicon carbide (SiC) based discrete power devices and electronics, has announced two new additions to its family of SiC JFETs (junction field-effect transistors), available in bare die form or TO-247 packages.

The first is a normally-off, 1700V SiC JFET targeted at the auxiliary power supply market for motor drives. Compared with the best silicon MOSFET technology, the new SJEP170R550 offers higher blocking voltage (1700V), five times lower on-resistance (550m-Ohm), and roughly ten times lower output capacitance (C OSS of 20pF) and gate charge (Q G of 10nC).

“This new 1700V, normally-off JFET offers the designer additional advantages compared to Si, including higher input voltages, better efficiency, including a significant double-digit efficiency improvement at high input voltages,” comments VP of sales & marketing Dan Schwob, citing early interest from customers looking for energy-efficient solutions for auxiliary switched-mode power supplies (SMPS).

Graphic: SemiSouth's normally-off 1700V SiC JFET offers higher blocking voltage, five times lower on-resistance, and about ten times lower output capacitance and gate charge than competing Si MOSFETs for auxiliary power supplies for drives.

The second new product (the SJDP120R085) is a normally-on version of the 1200V, normally-off SiC JFET. “Some customers have asked for a normally-on version of our normally-off SiC JFET products due to their topologies,” says Dr Jeff Casady chief technology officer & VP of business development. “This normally-on version is identical to the normally-off version; except that it has 15% lower R DSON [85m-Ohm], two times higher saturation current, and requires no gate current in the conduction mode,” he adds.

SemiSouth says that, since releasing its first, normally-off SiC FET in late 2008, it has seen widespread adoption of the power transistor because of its advantages in energy efficiency, reliability and cost relative to other SiC technologies.

SemiSouth says that emerging SiC technology enables energy-efficient operation of power conversion and power management in telecom power supplies, inverters in solar and high-frequency welding, future automotive electric vehicle platforms, and many other products. The firm adds that the promise of SiC is its ability to make power supplies and power inverters up to 50–75% more energy efficient, operate at up to 4–8 times higher frequency, and hence run cooler and be physically much smaller. In particular, SiC power JFETs are expected to increase the ‘fuel’ efficiency of hybrid electric vehicles and help to make them more affordable for consumers.

See related items:

SemiSouth announces reference design for 1200V SiC FET

SemiSouth claims first SiC JFET used in audio amplifier market

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