Nurnburg, Germany

The widespread use of active Power Factor Correction (PFC) circuit is becoming even more popular as government agencies demand more effective use of grid supply capacities. A typical PFC circuit includes a diode bridge for rectifying the ac source and a boost stage to force the input current proportional to the input voltage. The rectifier bridge consumes a significant part of the circuit loss; therefore, many topology innovations for bridge-less PFCs have emerged. But most suffer from either common mode (CM) electromagnetic interference (EMI) or other issues and, therefore, are not practical.

One unique topology called the totem pole PFC has both simple power loops and low

EMI [1]. However, this topology demands very-low reverse recovery charges (Qrr) for

the MOSFET body diodes – not possible with high-voltage Si MOSFETs. With the advent

of Gallium Nitride (GaN) power devices [2] [3], new 600V-class low Qrr transistors make this highly promising circuit a practical reality.

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Transphorm is redefining electric power conversion, providing cost-competitive and easy-to-embed power conversion modules that reduce costly energy loss by up to 90 percent, and simplify the design and manufacturing of motor drives, power supplies and inverters for solar panels and electric vehicles. From material technology and device fabrication to circuit design and module assembly, Transphorm designs and delivers its power conversion devices and modules to meet the needs of global customers, helping them scale quickly and save money. By creating an ecosystem of electrical systems manufacturers powered by Transphorm, the company accelerates the adoption of application-specific power modules and paves the way for the next generation of electrical systems designed for optimal efficiency. To learn more about Transphorm, please visit www.transphormusa.com.