Modeling and Reduction of Radiated EMI in a GaN IC-based Active Clamp Flyback Adapter

In modern power electronics, fast-switching Gallium-Nitride (GaN) devices can operate at the switching frequencies higher than conventional Si MOSFETs, so they help significantly reduce the size of passive components and increase power density. The active-clamp flyback (ACF) converter, operating at several hundred kHz to 1 MHz is a game-changer for high power-density and high-efficiency power adapters. With careful design, radiated EMI associated with fast-switching GaN devices can be reduced.

 A detailed EMI model was developed and validated in prototype form, with a focus on capacitive couplings in an ACF using Navitas’ GaNFast power ICs and a high-frequency planar transformer. The test platform was a high-density 450 kHz ACF using TI UCC28780 and Navitas NV6115+NV6117, with slew rate 20V/ns.

Thanks to Juntao Yao plus Professor Shuo Wang and Liming Yi of the University of Florida, with support from Navitas team members Xiucheng Huang and XiaoFeng Lyu. Click here for the full article (requires IEEE log-in, IEEE Transactions on Power Electronics, 20 October 2020, DOI: 10.1109/TPEL.2020.3032644).