1200-V MOSFETs claim superior performance than Si IGBTs and Superjunction MOSFETs
Alpha and Omega semiconductor Limited (AOS) and SemiSouth Laboratories are jointly demonstrating UniSiC, a new 1200 V, 90 mΩ MOSFET in a TO262 package, to meet the growing need for energy efficient switching devices for high performance power conversion applications in the alternative energy, industrial and consumer segments. The reduction in form factor and figures-of-merit put this 1200 V MOSFET device in a class by itself.

AOS continues to execute its strategy to be a full service power solution provider by extending its portfolio of AlphaMOS MOSFETs and AlphaIGBT, devices with the revolutionary 1200 V MOSFET solution described in this brief.

The UniSiC MOSFET provides unprecedented low Rdson and gate charge Qg, an excellent body diode with virtually no stored charge and a low diode forward voltage drop. The device may be used similar to a conventional MOSFET or IGBT, with standard gate drives and is engineered so it can be switched over a wide speed range – as fast as a Superjunction MOSFET, or as slow as an IGBT. The device has far superior characteristics compared to existing IGBTs, Silicon power MOSFETs or even the best competitive SiC 1200V MOSFET.  The small die size of the device points the way for future miniaturization of power circuits given how much it cuts conduction and switching losses.

The UniSiC device is formed by stacking a specially designed low voltage Silicon MOSFET atop a normally-on SiC JFET. The SiC JFET has excellent characteristics and is provided by SemiSouth, the leading supplier of SiC JFET technology. The low voltage MOSFET is specially engineered to allow optimal operation of the composite device with clean switching, low Rdson, gate charge and superb diode characteristics. It is intended to provide great ease of use, working with standard drive circuitry, and drastically improving circuit efficiencies over the whole range of load current.

Dr. Anup Bhalla, Vice President of High-Voltage Discretes at AOS, said: “The devices can be used like conventional discrete IGBTs and FETs using the same gate drives, allowing the user to realize huge efficiency gains without too much re-engineering.”