A 624 V 5 A All-GaN Integrated Cascode for Power-Switching Applications

An all-GaN integrated cascode device with an output current of 5 A, threshold voltage of +0.65 V and breakdown voltage of 624 V is demonstrated. Compared with the commercial 600 V hybrid GaN plus Si cascode device (TPH3202), the integrated cascode exhibits a significantly reduced delay time when switched at 200 V and 2.7 A. This is attributed to the absence of a Si metal-oxide-semiconductor field-effect transistor (MOSFET) driver, leading to a much smaller input capacitance as indicated by the high voltage capacitance measurements. In addition, the integrated cascode device shows a reduced ringing effect due to monolithic integration. When compared with commercial 600 V standalone GaN devices (GS66502B and GS-065-004), a reduced Miller effect is observed for the integrated cascode when switched under low gate-driving current conditions. The results demonstrate the advantages of the cascode device to switch with low gate-driving current using cheaper, faster, and more efficient gate drivers.