Comparison Study of Common-Mode Noise and Thermal Performance for Lateral Wire-Bonded and Vertically Integrated High Power Diode Modules

Abstract

This paper investigates the power module design for better common-mode (CM) noise and thermal performance. A high-frequency full-bridge diode rectifier is selected as a case study. The most influential factors in CM noise generation and mitigation are first identified with a simplified CM equivalent model and a comprehensive parametric study. Studies show proper parasitic value and parasitics symmetry can improve CM noise performance. The analysis of packaging structures indicates the vertical module has better CM noise and thermal performance than the traditional lateral wire-bonded module. To validate this, both modules are designed and prototyped for verification. The thermal simulation shows the vertical module exhibits a 25.5% lower thermal resistance from junction to case and a 51% increase of power density in a force-air-cooled condition. Experiments also reveal 15 dB of CM noise reduction from 150 kHz to 6 MHz and a 32% improvement of power density in a force-air-cooling condition. Finally, a case study demonstrates the vertical power module CM noise performance in a typical unsymmetrical topology. This results in a 30 dB CM noise reduction up to 6 MHz.