First industrial GaN transistor family with integrated Schottky diode

Infineon Technologies AG has released the world's first GaN power transistors with integrated Schottky diode for industrial use. The product family of medium-voltage CoolGaN Transistors G5 with integrated Schottky diode increases the performance of power systems by lowering undesired deadtime losses, further improving overall system efficiency. Also, the integrated solution simplifies the power stage design and decreases BOM cost.

In hard-switching applications, GaN-based topologies may incur higher power losses due to the larger effective body diode voltage (V SD) of GaN devices. This worsens with long controller deadtimes, resulting in lower efficiency than targeted. Until now, power design engineers have often needed an external Schottky diode parallel to the GaN transistor or tried to lower deadtimes via their controllers. All of these require extra effort, time, and cost. The new device greatly lessens these challenges by providing a GaN transistor with an integrated Schottky diode appropriate for usage in server and telecom IBCs, DC-DC converters, synchronous rectifiers for USB-C battery chargers, high-power PSUs, and motor drives.

"As gallium nitride technology becomes increasingly widespread in power designs, Infineon recognizes the need for continuous improvement and enhancement to meet the evolving demands of customers", says Antoine Jalabert, vice president of Infineon's Medium-Voltage GaN Product Line, "The CoolGaN Transistor G5 with Schottky diode exemplifies Infineon's dedication to an accelerated innovation-to-customer approach to push further the boundaries of what is possible with wide-bandgap semiconductor materials."

GaN transistor reverse conduction voltage (V RC) is dependent on the threshold voltage (V TH) and the OFF-state gate bias (V GS) due to the lack of a body diode. Moreover, the V TH of a GaN transistor is generally higher than the turn-on voltage of a silicon diode, leading to a disadvantage during the reverse conduction operation, also known as the third quadrant. Therefore, with this new CoolGaN Transistor, reverse conduction losses are lower, compatibility with a broader range of high-side gate drivers, and deadtime relaxed, wider controller compatibility results in a simpler design.

The first of several GaN transistors with an integrated Schottky diode is the 100V 1.5mOhm transistor in a 3mm x 5mm PQFN package.