UnitedSiC announces SiC JFET family for low power ACDC Flyback converters

March 19, 2019, Applied Power Electronics Conference (APEC) Anaheim CA, and Princeton, New Jersey: UnitedSiC, a manufacturer of silicon carbide (SiC) power semiconductors, today announced it has released a range of SiC JFET die suitable for co-packaging with a controller IC with built in low voltage MOSFET to fabricate an extremely fast, cascode-based, 20-100 W Flyback product. Ranging from 650 V to 1700 V, these normally-on SiC JFETs enable simplified start-up implementation with zero standby dissipation and are ideal for the large Flyback AC-DC applications market, including consumer adapters and auxiliary power supplies.

Controller IC manufacturers can benefit from the small die sizes with very low RDS(ON) and capacitances. The normally-on JFET helps meet light and no-load dissipation regulations when coupled with a low Qg low voltage MOSFET integrated in the controller IC.

SiC cascodes are extremely robust, due the inherent capability of SiC JFETs when it comes to handling repeated avalanche and short circuits. Since the SiC JFET is in series with the LV MOSFET in the control IC, the source of the normally-on JFET rises to 12 V before JFET turns off and the IC begins switching. This current path through the JFET can be used as a start-up supply for the controller IC. An auxiliary supply from the converter transformer is then gated-in when the converter starts running, with no further dissipation.

Typical low-power Flyback applications include consumer electronics chargers such as laptop and mobile device chargers (from 20 to 65 W). Other applications range from wide-input (up to 1400 V) Flyback auxiliary supplies for industrial applications such as motor drives to high power lighting applications such as long LED chains.

“With the addition of these new SiC JFETs, UnitedSiC now has one of the largest SiC power portfolios in the industry,” says UnitedSiC CEO Chris Dries. “We now have high-performance JFET functionality in both die and discrete package form.”

 

Availability

A total of seven die are currently available in wafer form only from UnitedSiC with voltage ratings from 650 V to 1700V and RDS(ON) values down to 140 milliohms, in three die sizes down to 0.8 x 0.8mm for ease of co-packaging.

 

About APEC

The Premier Event in Applied Power Electronics™, APEC focuses on the practical and applied aspects of the power electronics business. This is not just a designer's conference. APEC has something of interest for anyone involved in power electronics:

• Equipment OEMs that use power supplies and dc-dc converters in their equipment
• Designers of power supplies, dc-dc converters, motor drives, uninterruptable power supplies, inverters, and any other power electronic circuits, equipment and systems
• Manufacturers and suppliers of components and assemblies used in power electronics
• Manufacturing, quality and test engineers involved with power electronics equipment
• Marketing, sales, and anyone involved in the business of power electronics
• Compliance engineers testing and qualifying power electronics equipment or equipment that uses power electronics

 

About UnitedSiC

UnitedSiC develops innovative silicon carbide FET and diode power semiconductors that deliver the industry’s best SiC efficiency and performance for electric vehicle (EV) chargers, DC-DC converters and traction drives, as well as telecom/server power supplies, variable-speed motor drives, and solar PV inverters.