Design Considerations for GaN HEMT Multichip Half-bridge Module for High-Frequency Power Converters
CPES has created a design of a multichip Gallium-Nitride (GaN) power module for high-frequency power conversion. The module is designed with the HRL 600 V Gallium-Nitride (GaN) enhancement-mode HEMT device. To exploit the capability of fast switching with low loss from high-voltage GaN devices, different layout structures have been analyzed to reduce power loop parasitic inductance and improve switching performance. The approach investigated is based on a multi-chip module where small-current-rated dies are placed in parallel to achieve higher current handling capability. Finite-element analysis (FEA) and switching circuit simulation show that the multi-layer powerloop design can effectively reduce the gate loop inductance and voltage over-shoot on the devices. This multi-layer design also improves current sharing of the multi-chip module during switching operation.