Thermal Management Experience in GaN-Based DC-DC Converter

This article provides a comprehensive experience of thermal management considerations about GaN-based converters. It elucidates the thermal properties commonly found in transistor datasheets, encompassing parameters like transient thermal impedances and thermal resistances. The discussion extends to the thermal design strategy for top-side cooling, covering aspects such as Thermal Interface Material (TIM) and heatsink selection. Additionally, the article introduces a thermal model specifically for an interleaved Buck-Boost GaN transistor-based dc-dc converter, considering the scenario with a heatsink. This holistic examination contributes valuable insights to the field of thermal management in GaN-based converter designs. In the conclusive phase, the laboratory prototype of the interleaved GaN-based converter was subjected to testing at up to 5 kWoutput power and 300 kHz switching frequency, employing two distinct TIMs. The experimental results obtained from this comparison are thoroughly analyzed and presented in the article.