ECPE modular scaleable Power Electronics Building Block

Aim of this project is the development of an intelligent half-brdige, consisting of two parallel dies, for a 48 V, 10 kW "mild-hybrid" inverter or DC/DC application. To achieve this 100 V, 7 mΩ Galliumnitride dies from GaN Systems will be integrated into a prepackage with a resistiv temperature sensor. These prepackages will be soldered on a main board in a parallel half-bridge configuration. The main board consists of necessary system components and the power and signal connections to the bus.

The prepackages enable, similiar to the monolithic integration, the combination of sensors in close proximity to the actual die. In addition the backside of the chip can be contacted quite well to achieve an optimal thermal connection to the heatsink.

For this purpose a prepreg is laminated onto a copper substrate and a thermister trace is structured on it. Afterwars the GaN Die will be sintered on the surface and enclosed by several prepreg layers. By micro vias the contacts to the chip surface will be manufactured and afterwards structured by traces on the top of the prepackage.

On the main board several components like the gate-driver, the DC-link, the temperature read-out circuit, an overtemeperature protection and a minimal invasiv current sensor for the output current are located. In addition the connection to the heat sink is indicated.

• Thermal Study on Leadframe Dimensioning for High Power Dissipation and Low Inductance Commutation Cells
• Gate Driver Concept for Parallel Operation of Low-Voltage High-Current GaN Power Transistors for Mild-Hybrid Applications (DOI:  10.1109/APEC42165.2021.9487194)
• Asymmetric Packages for Optimal Performance of GaN-HEMT using PCB Fabrication Technology
• A 48 V, 300 kHz, High Current DC/DC-Converter Based on Paralleled, Asymmetrical & Thermally Optimized PCB Embedded GaN Packages with Integrated Temperature Sensor (DOI:  10.23919/ISPSD50666.2021.9452241)