GaN FETs step up performance, cut package footprint

March 16, 2017 // By Graham Prophet
Representing a step forward in performance and cost, the latest eGaN (gallium nitride) power FETs from Efficient Power Conversion (EPC), EPC2045 and EPC2047, are half the size of prior generation eGaN transistors with significantly higher performance.

Increasing performance while lowering the cost of off-the-shelf gallium nitride transistors, the EPC2045 (7 mΩ, 100V) and the EPC2047 (10 mΩ, 200V) eGaN FETs are aimed at applications including single stage 48V-to-load Open Rack server architectures, point-of-load converters, USB-C, and LiDAR. Wireless charging, multi-level AC-DC power supplies, robotics, and solar micro inverters are example applications for the 200 V EPC2047.

 

Widening the performance/cost gap with equivalent silicon power transistors, the 100V, 7 mΩ EPC2045, cuts the die size in half compared to the prior-generation EPC2001C eGaN FET. The 200V, 10 mΩ EPC2047 eGaN FET also cuts the size in half so that it is now about 15 times smaller than equivalently rated silicon MOSFETs.

 

Designers, sasys EPC, no longer have to choose between size and performance. The chip-scale packaging of eGaN products handles thermal conditions better than the plastic packaged MOSFETs since the heat is dissipated directly to the environment with chip-scale devices, whereas the heat from the MOSFET die is held within a plastic package. There are three development boards available to support easy in-circuit performance evaluation of the EPC2045 and the EPC2047 respectively.

 

EPC proposes that this marks the start of a “virtuous cycle” for the development of eGaN products; these devices have significantly lower capacitance than their silicon counterparts. This condition translates into lower gate drive losses and lower device switching losses at higher frequencies for the same on-resistance and voltage rating. In the case of the EPC2045, a 30% reduction in power loss with a 2.5% points better efficiency than the best comparable MOSFET has been achieved in a 48V to 5V circuit operating at 500 kHz switching frequency.

 

In contrast to silicon MOSFETs, the switching performance of eGaN FETs improves even though they are significantly smaller – this attribute introduces a “virtuous cycle” for eGaN products going forward that will result in continued introduction of smaller devices with higher performance. The