A Double-End Sourced Wire-Bonded Multichip SiC MOSFET Power Module With Improved Dynamic Current Sharing

This paper proposes a double-end sourced layout for multichip SiC MOSFET power module adopting conventional wire-bonded packaging technology. The unique design provides each MOSFET with two parallel commutation loops by incorporating a symmetrical pair of dc-bus terminals into the power module. This new layout provides symmetrical equivalent power loops to each paralleled MOSFET and thus enables consistent switching performances and equal dynamic current sharing for the paralleled MOSFETs. Compared to the conventional design, the proposed design reduces the equivalent power-loop stray inductance by more than 50% and achieves improved dynamic current sharing among devices. By mitigating the imbalance of the switching current, the new module design demonstrated reduced temperature differences among devices and decreased near-field radiation noise level compared to the conventional layout. These features can further help to improve the power module density by shrinking the heat sink and integrating the gate driver board with the power modules. In this paper, an analytic model has been proposed for fast prediction of the near-field radiation from the power module. Detailed design procedures and experimental validations are also included in this paper.