Thermal Management for Buck Converters Using Co-Packaged GaN Power HEMTs

Conference: PCIM Asia 2020 - International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management
11/16/2020 - 11/18/2020 at Shanghai, China

Proceedings: PCIM Asia 2020

Pages: 6Language: englishTyp: PDF

Deng, Gaoqiang; Luo, Xiaorong (University of Electronic Science and Technology of China, Chengdu, Sichuan, China)
Zhang, Weijia; Liang, Jingyuan; Li, Rophina; Kim, Namjee; Ng, Wai Tung (University of Toronto, Toronto, Ontario, Canada)
Fu, Fred (GaN Power International, Canada)

A custom designed half-bridge power module with co-packaged low-side and high-side 15 A enhancement-mode GaN HEMTs is investigated. The power conversion efficiency is increased at light load but decreased at large load currents due to the limited thermal dissipation. Attaching a heatsink to the integrated package can effectively improve the power conversion efficiency under heavy loads. The tested 24-to-5 V converter achieves a peak efficiency of 91% at an output power of 4.5 W and a switching frequency (f) of 1 MHz. A dual-phase buck converter using two half-bridge GaN HEMT modules can further increase the output power while maintain high conversion efficiency when compared to a single-phase buck converter using the same GaN HEMTs in standard TO-220 package. The tested peak efficiency of the dual-phase 24-to-5 V converter is up to 90% at an output power of 10 W and f = 1 MHz.