UK-based semiconductor company Cambridge GaN Devices (CGD) has developed gallium nitride (GaN) technology that combines its ICeGaN HEMT integrated circuits (ICs) and Insulated-Gate Bipolar Transistors (IGBTs) in the same module for EV powertrain applications over 100 kW.
The Combo ICeGaN approach takes advangage of the fact that ICeGaN and IGBT devices can be operated in a parallel architecture having similar drive voltage ranges (e.g. 0-20 V) and strong gate robustness.
The ICeGaN switch is highly efficient and offers a cost-effective alternative to silicon carbide (SiC) products. It is characterized by low conduction and low switching losses at relatively low currents (light load), while the IGBT is dominant at relatively high currents (towards full load or during surge conditions).
At higher temperatures, the bipolar component of the IGBT starts to conduct at lower on-state voltages, supplementing the loss of current in the ICeGaN. Conversely, at lower temperatures, ICeGaN will take more current.
Sensing and protection functions are intelligently managed to optimally drive the Combo ICeGaN and enhance the Safe Operating Area (SOA) of both ICeGaN and IGBT devices.
ICeGaN technology allows EV engineers to use GaN in DC-to-DC converters, on-board chargers and potentially traction inverters.
CGD has also proven similar, parallel combinations of ICeGaN devices with SiC MOSFETs, but Combo ICeGaN is more economical, the company said. It expects to have working demos of the technology at the end of this year.
“ICeGaN is extremely fast and a star performer at light load conditions, while the IGBT brings great benefits during full load, surge conditions and at high temperatures. ICeGaN provides on-chip intelligence while the IGBT provides avalanche capability. They both embrace silicon substrates which come with cost, infrastructure and manufacturability advantages,” said Professor Florin Udrea, CGD’s founder and CTO.
Source: Cambridge GaN Devices
