Adjusting SiC MOSFET modules for size, reliability

Article By : Graham Prophet

The solution addresses SiC IPMs in hermetically sealed packages currently in development for harsh environments.

High temperature semiconductor solutions Cissoid has teamed up with Data Device Corporation (DDC) and subsidiary Beta Transformer Technology Corporation (BTTC) to develop more compact and reliable silicon carbide (SiC) MOSFET intelligent power modules (IPMs) for aerospace power converters and motor control.

Under the partnership, BTTC will develop high reliability and high temperature transformer modules, embedding both power and pulse transformers, and optimised for Cissoid HADES2 isolated gate driver. This solution will be used in SiC MOSFET IPM developed by Cissoid, making them more compact and reliable. It will address SiC IPMs developed for high power density applications but also IPMs in hermetically sealed packages currently in development for harsh environments, e.g. unpressurised locations and/or extreme temperatures.

Firstly, transformers modules are being developed, validated and qualified for temperature ranges from -55°C and up to 225°C. Magnetic cores and other transformer materials have been carefully selected to offer a stable behaviour and a reliable operation within this range.

The transformers will provide isolation in excess of 2500Vdc and are optimised for very low parasitic capacitances in order to support high dV/dt, typically up to 50kV/µsec, common with fast switching SiC transistors. These transformers have been optimised to work with the HADES2 isolated gate driver chipset: the power transformer is used inside a flyback DC-DC converter supplying both low- and high-side isolated gate drivers while pulse transformers are transmitting PWM and faults signals.